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Thought to be monotypic for decades, the only species in the goosefish genus Lophiomus Gill, Lm. setigerus (Vahl), shows a wide range of morphological variation and is distributed widely in the Indo-West Pacific (IWP). In this study, datasets for two mitochondrial and two nuclear genes sequences obtained from samples of Lophiomus collected in different localities across the IWP were constructed and analyzed to explore the phylogeny and species diversity within the genus. Our integrated approach with multiline evidence unveiled an unanticipated richness of at least six delimited species of Lophiomus. Herein, based on materials already available from museums and new specimens obtained primarily through the Tropical Deep-Sea Benthos program surveying IWP benthic fauna, we formally describe three new species: Lm. immaculioralis sp. nov., Lm. nigriventris sp. nov., and Lm. carusoi sp. nov. Also, we resurrect Lm. laticeps stat. rev. from synonyms of Lm. setigerus. These species can be diagnosed by genetics, body coloration, patterns on the floor of the mouth, peritoneum pigmentation, morphometric measurements, and meristic counts of cranial spines, dorsal-fin spines, and pectoral-fin and pelvic-fin rays from each other and from Lm. setigerus. The species Lm. setigerus, as well as the genus Lophiomus, are re-described accordingly based on the new results. Amended identification keys to the four extant lophiid genera and to species of Lophiomus are also provided.
The compulsive habit of cars
(2014)
The car dependence of people living in contemporary cities is a major concern for policy makers, who often find it difficult to persuade people into more sustainable transport modes. By contrast, recent insights from neuroscience have shown that a broad spectrum of behaviors can become habitual and, thus, resistant to change. Here, we outline the potential of collaboration between neuroscience and human geography aiming at a better understanding of habits that determine everyday commuting routines.
Sparse sensor networks for Lamb wave-based structural health monitoring (SHM) can detect defects in plate-like structures. However, the limited number of sensor positions provides little information to characterize the unknown scatterer. This can be achieved by full wavefield analysis e.g. using Laser Doppler vibrometry measurements.
This paper proposes deconvolution processing that enhances the acoustic wavefield interpretation by increasing the temporal resolution of the underlying ultrasound signals. Applying this preprocessor to the whole wavefield allows improved non-destructive assessment of the defect. This approach is verified experimentally through a case study on an isotropic aluminum plate with four cracks.
Inhibitors of the mammalian target of rapamycin (mTOR) have improved the treatment of renal cell carcinoma (RCC). However, chronic drug exposure may trigger resistance, limiting the utility of these agents. The metastatic behavior of RCC cells, susceptible (RCC(par)) or resistant (RCC(res)) to the mTOR inhibitor temsirolimus, was investigated. Adhesion to vascular endothelium or immobilized collagen and fibronectin was quantified. Chemotactic motility was evaluated with a modified Boyden chamber assay. Integrin α and β subtype receptors were analyzed by flow cytometry and Western blot analysis. The physiological relevance of the integrins was then determined by blocking studies and small interfering RNA knockdown. Adhesion to endothelial cells and to fibronectin (not to collagen) and chemotaxis were enhanced in RCC(res) compared to RCC(par). RCC(res) detached from fibronectin and motile activity further increased under retreatment with low-dosed temsirolimus. α5 integrin was diminished inside the cell and at the cell surface, whereas the β3 subtype was reduced intracellularly but elevated at the plasma membrane. In RCC(par), blocking α5 surface receptors enhanced RCC-collagen but reduced RCC-fibronectin interaction, whereas the opposite was true for RCC(res). Chemotaxis of RCC(par) but not of RCC(res) was strongly diminished by the α5 antibody. Blocking β3 significantly lowered chemotaxis with stronger effects on RCC(res), compared to RCC(par). Importantly, β3 knockdown reduced chemotaxis of RCC(par) but upregulated the motile behavior of RCC(res). Temsirolimus resistance is characterized by quantitative alterations of integrin α5 and β3 expression, coupled to functional changes of the integrin molecules, and forces a switch from RCC adhesion to RCC migration.
Antigen presentation to cytotoxic T lymphocytes via major histocompatibility complex class I (MHC I) molecules depends on the heterodimeric transporter associated with antigen processing (TAP). For efficient antigen supply to MHC I molecules in the ER, TAP assembles a macromolecular peptide-loading complex (PLC) by recruiting tapasin. In evolution, TAP appeared together with effector cells of adaptive immunity at the transition from jawless to jawed vertebrates and diversified further within the jawed vertebrates. Here, we compared TAP function and interaction with tapasin of a range of species within two classes of jawed vertebrates. We found that avian and mammalian TAP1 and TAP2 form heterodimeric complexes across taxa. Moreover, the extra N-terminal domain TMD0 of mammalian TAP1 and TAP2 as well as avian TAP2 recruits tapasin. Strikingly, however, only TAP1 and TAP2 from the same taxon can form a functional heterodimeric translocation complex. These data demonstrate that the dimerization interface between TAP1 and TAP2 and the tapasin docking sites for PLC assembly are conserved in evolution, whereas elements of antigen translocation diverged later in evolution and are thus taxon specific.
While it is extraordinarily difficult to theoretically specify privacy, in the last 100 years or so (social) psychology, philosophy, communication studies, economics, and, to a lesser degree, also sociology and anthropology, provided attempts to conceptualize its meaning. Be that as it may, from the 1960s onwards privacy discourse has focused upon data, understood as “personal information”, to a certain extent because of the advent of huge databases and information and communication technologies (ICTs). Influential scholarship at the present time tends to conceive of ICT-related privacy in terms of the “sociotechnical”, thus highlighting the interlocking of human and technical agency. Although having developed a manifold of instruments to research sociotechnical phenomena, STS engagement with sociotechnical privacy, so far, has been rather low-key. In our contribution we therefore provide a mapping of the research landscape, identify connecting factors between STS and sociotechnical privacy research, and calling for further STS contributions.
Several microRNAs (miRNAs) are associated with the molecular pathogenesis of hepatocellular carcinoma (HCC). However, previous studies analyzing the dysregulation of miRNAs in HCC show heterogeneous results. We hypothesized that part of this heterogeneity might be attributable to variations of miRNA expression deriving from the HCC capsule or the fibrotic septa within the peritumoral tissue used as controls. Tissue from surgically resected hepatitis C–associated HCC from six well-matched patients was microdissected using laser microdissection and pressure catapulting technique. Four distinct histologic compartments were isolated: tumor parenchyma (TP), fibrous capsule of the tumor (TC), tumor-adjacent liver parenchyma (LP), and cirrhotic septa of the tumor-adjacent liver (LC). MiRNA expression profiling analysis of 1105 mature miRNAs and precursors was performed using miRNA microarray. Principal component analysis and consecutive pairwise supervised comparisons demonstrated distinct patterns of expressed miRNAs not only for TP versus LP (e.g., intratumoral down-regulation of miR-214, miR-199a, miR-146a, and miR-125a; P< .05) but also for TC versus LC (including down-regulation within TC of miR-126, miR-99a/100, miR-26a, and miR-125b; P< .05). The tumor capsule therefore demonstrates a tumor-like phenotype with down-regulation of well-known tumor-suppressive miRNAs. Variations of co-analyzed fibrotic tissue within the tumor or in controls may have profound influence on miRNA expression analyses in HCC. Several miRNAs, which are proposed to be HCC specific, may indeed be rather associated to the tumor capsule. As miRNAs evolve to be important biomarkers in liver tumors, the presented data have important translational implications on diagnostics and treatment in patients with HCC.
The traffic AAA-ATPase PilF is essential for pilus biogenesis and natural transformation of Thermus thermophilus HB27. Recently, we showed that PilF forms hexameric complexes containing six zinc atoms coordinated by conserved tetracysteine motifs. Here we report that zinc binding is essential for complex stability. However, zinc binding is neither required for pilus biogenesis nor natural transformation. A number of the mutants did not exhibit any pili during growth at 64 °C but still were transformable. This leads to the conclusion that type 4 pili and the DNA translocator are distinct systems. At lower growth temperatures (55 °C) the zinc-depleted multiple cysteine mutants were hyperpiliated but defective in pilus-mediated twitching motility. This provides evidence that zinc binding is essential for the role of PilF in pilus dynamics. Moreover, we found that zinc binding is essential for complex stability but dispensable for ATPase activity. In contrast to many polymerization ATPases from mesophilic bacteria, ATP binding is not required for PilF complex formation; however, it significantly increases complex stability. These data suggest that zinc and ATP binding increase complex stability that is important for functionality of PilF under extreme environmental conditions.
In the search for novel organic charge transfer salts with variable degrees of charge transfer we have studied the effects of two modifications of the recently synthesized donor–acceptor system [tetramethoxypyrene (TMP)]–[tetracyanoquinodimethane (TCNQ)]. One is of chemical nature by substituting the acceptor TCNQ molecules by F4TCNQ molecules. The second consists in simulating the application of uniaxial pressure along the stacking axis of the system. In order to test the chemical substitution, we have grown single crystals of the TMP–F4TCNQ complex and analyzed its electronic structure via electronic transport measurements, ab initio density functional theory (DFT) calculations and UV/VIS/IR absorption spectroscopy. This system shows an almost ideal geometrical overlap of nearly planar molecules stacked alternately (mixed stack) and this arrangement is echoed by a semiconductor-like transport behavior with an increased conductivity along the stacking direction. This is in contrast to TMP–TCNQ which shows a less pronounced anisotropy and a smaller conductivity response. Our band structure calculations confirm the one-dimensional behavior of TMP–F4TCNQ with pronounced dispersion only along the stacking axis. Infrared measurements illustrating the C[triple bond, length as m-dash]N vibration frequency shift in F4TCNQ suggest however no improvement in the degree of charge transfer in TMP–F4TCNQ with respect to TMP–TCNQ. In both complexes about 0.1e is transferred from TMP to the acceptor. Concerning the pressure effect, our DFT calculations on the designed TMP–TCNQ and TMP–F4TCNQ structures under different pressure conditions show that application of uniaxial pressure along the stacking axis of TMP–TCNQ may be the route to follow in order to obtain a much more pronounced charge transfer.
The phase diagram of the square lattice bilayer Hubbard model: a variational Monte Carlo study
(2014)
We investigate the phase diagram of the square lattice bilayer Hubbard model at half-filling with the variational Monte Carlo method for both the magnetic and the paramagnetic case as a function of the interlayer hopping and on-site Coulomb repulsion U. With this study we resolve some discrepancies in previous calculations based on the dynamical mean-field theory, and we are able to determine the nature of the phase transitions between metal, Mott insulator and band insulator. In the magnetic case we find only two phases: an antiferromagnetic Mott insulator at small for any value of U and a band insulator at large . At large U values we approach the Heisenberg limit. The paramagnetic phase diagram shows at small a metal to Mott insulator transition at moderate U values and a Mott to band insulator transition at larger U values. We also observe a re-entrant Mott insulator to metal transition and metal to band insulator transition for increasing in the range of . Finally, we discuss the phase diagrams obtained in relation to findings from previous studies based on different many-body approaches.
Recent density functional theory (DFT) calculations for KFe2As2 have been shown to be insufficient to satisfactorily describe angle-resolved photoemission (ARPES) measurements as well as observed de Haas–van Alphen (dHvA) frequencies. In the present work, we extend DFT calculations based on the full-potential linear augmented plane-wave method by dynamical mean field theory (DFT+DMFT) to include correlation effects beyond the local density approximation. We present results for two sets of reported crystal structures. Our calculations indicate that KFe2As2 is a moderately correlated metal with a mass renormalization factor of the Fe $3{\rm d}$ orbitals between 1.6 and 2.7. Furthermore, the obtained shape and size of the Fermi surface are in good agreement with ARPES measurements and we observe some topological changes with respect to DFT calculations such as the opening of an inner hole cylinder at the Z point. As a result, our calculated dHvA frequencies differ greatly from existing DFT results and qualitatively agree with experimental data. On this basis, we argue that correlation effects are important to understand the -presently under debate- nature of the superconducting state in KFe2As2.
The hydrophobic thickness of membranes, which is manly defined by fatty acids, influences the packing of transmembrane domains of proteins and thus can modulate the activity of these proteins. We analyzed the dynamics of the dimerization of Glycophorin A (GpA) by molecular dynamics simulations to describe the fatty acid dependence of the transmembrane region assembly. GpA represents a well-established model for dimerization of single transmembrane helices containing a GxxxG motif in vitro and in silico. We performed simulations of the dynamics of the NMR-derived dimer as well as self-assembly simulations of monomers in membranes composed of different fatty acid chains and monitored the formed interfaces and their transitions. The observed dimeric interfaces, which also include the one known from NMR, are highly dynamic and converted into each other. The frequency of interface formation and the preferred transitions between interfaces similar to the interface observed by NMR analysis strongly depend on the fatty acid used to build the membrane. Molecular dynamic simulations after adaptation of the helix topology parameters to better represent NMR derived structures of single transmembrane helices yielded an enhanced occurrence of the interface determined by NMR in molecular dynamics simulations. Taken together we give insights into the influence of fatty acids and helix conformation on the dynamics of the transmembrane domain of GpA.
Analysis of whole cell lipid extracts of bacteria by means of ultra-performance (UP)LC-MS allows a comprehensive determination of the lipid molecular species present in the respective organism. The data allow conclusions on its metabolic potential as well as the creation of lipid profiles, which visualize the organism's response to changes in internal and external conditions. Herein, we describe: i) a fast reversed phase UPLC-ESI-MS method suitable for detection and determination of individual lipids from whole cell lipid extracts of all polarities ranging from monoacylglycerophosphoethanolamines to TGs; ii) the first overview of a wide range of lipid molecular species in vegetative Myxococcus xanthus DK1622 cells; iii) changes in their relative composition in selected mutants impaired in the biosynthesis of α-hydroxylated FAs, sphingolipids, and ether lipids; and iv) the first report of ceramide phosphoinositols in M. xanthus, a lipid species previously found only in eukaryotes.
ω-Azido fatty acids as probes to detect fatty acid biosynthesis, degradation, and modification
(2014)
FAs play a central role in the metabolism of almost all known cellular life forms. Although GC-MS is regarded as a standard method for FA analysis, other methods, such as HPLC/MS, are nowadays widespread but are rarely applied to FA analysis. Here we present azido-FAs as probes that can be used to study FA biosynthesis (elongation, desaturation) or degradation (β-oxidation) upon their uptake, activation, and metabolic conversion. These azido-FAs are readily accessible by chemical synthesis and their matization with high sensitivity by HPLC/MS, contributing a powerful tool to FA analysis, and hence, lipid analysis in general.
Background: Influenza vaccination of healthcare workers (HCWs) is recommended to prevent the transmission of influenza to vulnerable patients. Nevertheless, vaccination coverage rates of HCWs in European countries have been low.
Aim: To investigate the relative and combined strength of sociocognitive variables, from past research, theory and a qualitative study, in explaining the motivation of HCWs to receive the influenza vaccine.
Methods: An anonymous, online questionnaire was distributed among HCWs in hospital settings in Belgium, Germany and the Netherlands between February and April 2013.
Findings: Attitude and past vaccination uptake explained a considerable amount of variance in the intention of HCWs to receive the influenza vaccine. Moreover, low perceived social norms, omission bias, low moral norms, being older, having no patient contact, and being Belgian or Dutch (compared with German) increased the probability of having no intention to receive the influenza vaccine compared with being undecided about vaccination. High intention to receive the influenza vaccine was shown to be more likely than being undecided about vaccination when HCWs had high perceived susceptibility of contracting influenza, low naturalistic views, and lower motivation to receive the vaccine solely for self-protection.
Conclusion: Country-specific interventions and a focus on different sociocognitive variables depending on the intention/lack of intention of HCWs to receive the influenza vaccine may be beneficial to promote vaccination uptake.
The title solvated salt, C29H41N2+·Br-·2CH2Cl2 was obtained from the reaction of the Arduengo-type carbene 1,3-bis(2,6-diisopropylphenyl)-1,3-dihydro-4,5-dimethyl-2H-imidazol-2-ylidene with Si2Br6 in dichloromethane. The complete cation is generated by a crystallographic mirror plane and the dihedral angle between the five-membered ring and the benzene ring is 89.8 (6)°; the dihedral angle between the benzene rings is 40.7 (2)°. The anion also lies on the mirror plane and both dichloromethane molecules are disordered across the mirror plane over two equally occupied orientations. In the crystal, the cations are linked to the anions via C-H...Br hydrogen bonds.
The ALICE Zero Degree Calorimeter system (ZDC) is composed of two identical sets of calorimeters, placed at opposite sides with respect to the interaction point, 114 meters away from it, complemented by two small forward electromagnetic calorimeters (ZEM). Each set of detectors consists of a neutron (ZN) and a proton (ZP) ZDC. They are placed at zero degrees with respect to the LHC axis and allow to detect particles emitted close to beam direction, in particular neutrons and protons emerging from hadronic heavy-ion collisions (spectator nucleons) and those emitted from electromagnetic processes. For neutrons emitted by these two processes, the ZN calorimeters have nearly 100% acceptance.
During the √sNN = 2.76 TeV Pb-Pb data-taking, the ALICE Collaboration studied forward neutron emission with a dedicated trigger, requiring a minimum energy deposition in at least one of the two ZN. By exploiting also the information of the two ZEM calorimeters it has been possible to separate the contributions of electromagnetic and hadronic processes and to study single neutron vs. multiple neutron emission.
The measured cross sections of single and mutual electromagnetic dissociation of Pb nuclei at √sNN = 2.76 TeV, with neutron emission, are σsingle EMD = 187:4 ± 0.2 (stat.)−11.2+13.2 (syst.) b and σmutual EMD = 5.7 ± 0.1 (stat.) ±0.4 (syst.) b, respectively [1]. This is the first measurement of electromagnetic dissociation of 208Pb nuclei at the LHC energies, allowing a test of electromagnetic dissociation theory in a new energy regime. The experimental results are compared to the predictions from a relativistic electromagnetic dissociation model.
Single-pion production in proton-proton collisions at 1.25 GeV: measurements by HADES and a PWA
(2014)
We report on the single-pion production in proton-proton collisions at a kinetic energy of 1.25 GeV based on data measured with HADES. Exclusive channels npπ+ and ppπ0 were studied simultaneously. The parametrization of production cross sections of the one-pion final states by means of the resonance model has been obtained. Independently, the extraction of the leading partial waves in the data were analyzed within the framework of the partial wave analysis (PWA). Contributions for the production of ∆(1232) and N(1440) intermediate states have been deduced.
Event-by-event fluctuations of the mean transverse momentum of charged particles produced in pp collisions at s√ = 0.9, 2.76 and 7 TeV, and Pb-Pb collisions at sNN−−−−√ = 2.76 TeV are studied as a function of the charged-particle multiplicity using the ALICE detector at the LHC. Dynamical fluctuations indicative of correlated particle emission are observed in all systems. The results in pp collisions show little dependence on collision energy. The Monte Carlo event generators PYTHIA and PHOJET are in qualitative agreement with the data. Peripheral Pb-Pb data exhibit a similar multiplicity dependence as that observed in pp. In central Pb-Pb, the results deviate from this trend, featuring a significant reduction of the fluctuation strength. The results in Pb--Pb are in qualitative agreement with previous measurements in Au-Au at lower collision energies and with expectations from models that incorporate collective phenomena.
Na(+)/H(+) exchangers are essential for regulation of intracellular proton and sodium concentrations in all living organisms. We examined and experimentally verified a kinetic model for Na(+)/H(+) exchangers, where a single binding site is alternatively occupied by Na(+) or one or two H(+) ions. The proposed transport mechanism inherently down-regulates Na(+)/H(+) exchangers at extreme pH, preventing excessive cytoplasmic acidification or alkalinization. As an experimental test system we present the first electrophysiological investigation of an electroneutral Na(+)/H(+) exchanger, NhaP1 from Methanocaldococcus jannaschii (MjNhaP1), a close homologue of the medically important eukaryotic NHE Na(+)/H(+) exchangers. The kinetic model describes the experimentally observed substrate dependences of MjNhaP1, and the transport mechanism explains alkaline down-regulation of MjNhaP1. Because this model also accounts for acidic down-regulation of the electrogenic NhaA Na(+)/H(+) exchanger from Escherichia coli (EcNhaA, shown in a previous publication) we conclude that it applies generally to all Na(+)/H(+) exchangers, electrogenic as well as electroneutral, and elegantly explains their pH regulation. Furthermore, the electrophysiological analysis allows insight into the electrostatic structure of the translocation complex in electroneutral and electrogenic Na(+)/H(+) exchangers.