Results 401  450 of 1199  
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Mitterboeck T Fatima TF Department of Integrative Biology and Biodiversity Institute of Ontario, University of Guelph, 50 Stone Road East, Guelph, Ontario, Canada N1G 2W1.   2013
The loss of flight ability has occurred thousands of times independently during insect evolution. Flight loss may be linked to higher molecular evolutionary rates because of reductions in effective population sizes (Ne) and relaxed selective constraints. Reduced dispersal ability increases population subdivision, may decrease geographical range size and increases (sub)population ...


Burness Gary G Department of Biology, Trent University, Peterborough, Ontario, Canada K9J 7B8.   2013
Across taxa, the early rearing environment contributes to adult morphological and physiological variation. For example, in birds, environmental temperature plays a key role in shaping bill size and clinal trends across latitudinal/thermal gradients. Such patterns support the role of the bill as a thermal window and in thermal balance. It ...


Jones James Holland JH Woods Institute for Environment, Stanford University, Stanford, CA 943052034, USA.   2013
In this paper, we attempt to understand huntergatherer foraging decisions about prey that vary in both the mean and variance of energy return using an expected utility framework. We show that for skewed distributions of energetic returns, the standard linear variance discounting (LVD) model for risksensitive foraging can produce quite ...


Rusakiewicz Sylvie S INSERM U1015, Institut Gustave Roussy (IGR), 94805 Villejuif,   2013
Primary Sjögren's syndrome (pSS) is a chronic autoimmune disease characterized by a lymphocytic exocrinopathy. However, patients often have evidence of systemic autoimmunity, and they are at markedly increased risk for the development of non Hodgkin's lymphoma. Similar to other autoimmune disorders, a strong interferon (IFN) signature is present among subsets ...


Sonego Martina M Wolfson Centre for AgeRelated Diseases, King's College London, Guy's Campus, London SE1 1UL, United   2013
After birth, stem cells in the subventricular zone (SVZ) generate neuroblasts that migrate along the rostral migratory stream (RMS) to become interneurons in the olfactory bulb (OB). This migration is a fundamental event controlling the proper integration of new neurons in a preexisting synaptic network. Many regulators of neuroblast migration ...


Lenaghan Scott C SC Department of Mechanical, Aerospace and Biomedical Engineering, University of Tennessee, Knoxville, TN 37996,   2013
Bioinspiration for novel adhesive development has drawn increasing interest in recent years with the discovery of the nanoscale morphology of the gecko footpad and mussel adhesive proteins. Similar to these animal systems, it was discovered that English ivy (Hedera helix L.) secretes a high strength adhesive containing uniform nanoparticles. Recent ...


Girard Michaël J A MJ Department of Bioengineering, National University of Singapore, Singapore, Republic of Singapore.   2013
Measurement of optic nerve head (ONH) deformations could be useful in the clinical management of glaucoma. Here, we propose a novel threedimensional tissuetracking algorithm designed to be used in vivo. We carry out preliminary verification of the algorithm by testing its accuracy and its robustness. An algorithm based on digital ...


Lan Ganhui G Department of Physics, George Washington University, 725 21st Street NW, Washington, DC 20052,   2013
The incoherent type1 feedforward loop (I1FFL) is ubiquitous in biological regulatory circuits. Although much is known about the functions of the I1FFL motif, the energy cost incurred in the network and how it affects the performance of the network have not been investigated. Here, we study a generic I1FFL enzymatic ...


Ahn KangHun KH Department of Physics, Chungnam National University, Daejeon 305764, Republic of Korea.   2013
In the ear, hair cells transform mechanical stimuli into neuronal signals with great sensitivity, relying on certain active processes. Individual hair cell bundles of nonmammals such as frogs and turtles are known to show spontaneous oscillation. However, hair bundles in vivo must be quiet in the absence of stimuli, otherwise ...


Bruot Nicolas N Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE,   2013
As a model of ciliary beat, we use twostate oscillators that have a defined direction of oscillation and have strong synchronization properties. By allowing the direction of oscillation to vary according to the interaction with the fluid, with a timescale longer than the timescale of synchronization, we show in simulations ...


Feliu Elisenda E Department of Mathematical Sciences, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen,   2013
Mathematical models are increasingly being used to understand complex biochemical systems, to analyse experimental data and make predictions about unobserved quantities. However, we rarely know how robust our conclusions are with respect to the choice and uncertainties of the model. Using algebraic techniques, we study systematically the effects of intermediate, ...


Kwan Lucia L Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario, Canada.   2013
Poeciliid fish, freshwater fish with internal fertilization, are known for the diversity of structures on the male intromittent organ, the gonopodium. Prominent among these, in some species, is a pair of claws at its tip. We conducted a manipulative study of these claws in the guppy, Poecilia reticulata, to determine ...


Schrader Matthew M Department of Biological Science, Florida State University, Tallahassee, FL 323061100, USA.   2013
Crosses between populations or species often display an asymmetry in the fitness of reciprocal F1 hybrids. This pattern, referred to as isolation asymmetry or Darwin's Corollary to Haldane's Rule, has been observed in taxa from plants to vertebrates, yet we still know little about which factors determine its magnitude and ...


McKenzie Scott W SW Centre for Ecology and Hydrology (CEH), Bush Estate, Penicuik, Midlothian, UK.   2013
Interspecific interactions between insect herbivores predominantly involve asymmetric competition. By contrast, facilitation, whereby herbivory by one insect benefits another via induced plant susceptibility, is uncommon. Positive reciprocal interactions between insect herbivores are even rarer. Here, we reveal a novel case of reciprocal feeding facilitation between aboveground aphids (Amphorophora idaei) and ...


Hetem Robyn S RS Brain Function Research Group, School of Physiology, Faculty of Health Sciences, University of the Witwatersrand Medical School, Parktown 2193, South Africa.   2013
Hunting cheetah reportedly store metabolic heat during the chase and abandon chases because they overheat. Using biologging to remotely measure the body temperature (every minute) and locomotor activity (every 5 min) of four freeliving cheetah, hunting spontaneously, we found that cheetah abandoned hunts, but not because they overheated. Body temperature ...


Caprioli Manuela M Department of Biosciences, University of Milan, Milano,   2013
Telomere length and dynamics are increasingly scrutinized as ultimate determinants of performance, including agedependent mortality and fecundity. Few studies have investigated longevity in relation to telomere length (TL) in the wild and none has analysed longevity in relation to TL soon after hatching, despite the fact that telomere shortening may ...


Stanley William T WT Science and Education, Field Museum of Natural History, Chicago, IL, USA.   2013
The hero shrew's (Scutisorex somereni) massive interlocking lumbar vertebrae represent the most extreme modification of the vertebral column known in mammals. No intermediate form of this remarkable morphology is known, nor is there any convincing theory to explain its functional significance. We document a new species in the heretofore monotypic ...


  2013
HHS is issuing this final rule to clarify how section 340B(e) of the Public Health Service Act (PHSA) will be implemented. The final rule applies section 340B(e) of the PHSA only to drugs transferred, prescribed, sold, or otherwise used for the rare condition or disease for which the orphan drug ...


Sergi Alessandro   2013
A formalism for studying the dynamics of quantum systems embedded in classical spin baths is introduced. The theory is based on generalized antisymmetric brackets and predicts the presence of openpath offdiagonal geometric phases in the evolution of the density matrix. The weak coupling limit of the equation can be integrated ...


Aragones J L   2013
In this work, we describe a procedure to evaluate the free energy of molecular solids with the GROMACS molecular dynamics package. The free energy is calculated using the Einstein molecule method that can be regarded as a small modification of the Einstein crystal method. Here, the position and orientation of ...


Hoy Erik P   2013
Lowrank spectral expansion and tensor hypercontraction are two promising techniques for reducing the size of the twoelectron excitation tensor by factorizing it into products of smaller tensors. Both methods can potentially realize an O(r(4)) quantum chemistry method where r is the number of oneelectron orbitals. We compare the two factorizations ...


Walther Christian F J   2013
Quantized Liquid DensityFunctional Theory (QLDFT) [S. Patchkovskii and T. Heine, Phys. Rev. E 80, 031603 (2009)], a method developed to assess the adsorption of gas molecules in porous nanomaterials, is reformulated within the grand canonical ensemble. With the grand potential it is possible to compare directly external and internal thermodynamic ...


Hermes Matthew R   2013
Secondorder manybody perturbation theories for anharmonic vibrational frequencies and zeropoint energies of molecules are formulated, implemented, and tested. They solve the vibrational Dyson equation selfconsistently by taking into account the frequency dependence of the Dyson selfenergy in the diagonal approximation, which is expanded in a diagrammatic perturbation series up to ...


Xiao Yunlong   2013
The relativistic molecular Hamiltonian written in the bodyfixed frame of reference is the basis for highprecision calculations of spectroscopic parameters involving nuclear vibrations and/or rotations. Such a Hamiltonian that describes electrons fully relativistically and nuclei quasirelativistically is just developed for semirigid nonlinear molecules [Y. Xiao and W. Liu, J. Chem. ...


Golschleger I U   2013
We present the moving picture of a molecular bond, in phasespace, in realtime, at resolution limited by quantum uncertainty. The images are tomographically reconstructed Wigner distribution functions (WDF) obtained from fourwave mixing measurements on Br2doped ice. The WDF completely characterizes the dissipative quantum evolution of the system, which despite coupling ...


Tecmer Paweł   2013
We present an EOMCCSD (equation of motion coupled cluster with singles and doubles) study of excited states of the small [UO2](2+) and [UO2](+) model systems as well as the larger U(VI)O2(saldien) complex. In addition, the triples contribution within the EOMCCSDT and CREOMCCSD(T) (completely renormalized EOMCCSD with noniterative triples) approaches for ...


Wang Lecheng   2013
A sixdimensional ab initio potential energy surface (PES) for H2N2O which explicitly includes the symmetric and asymmetric vibrational coordinates Q1 and Q3 of N2O is calculated at the coupledcluster singles and doubles with noniterative inclusion of connected triple level using an augmented correlationconsistent polarizedvalence quadruplezeta basis set together with midpoint ...


Han Jiao   2013
Delocalized excitons in elementary linear J aggregates of twolevel molecules absorb a photon into the lowenergy edge of an exciton band. Absorption of a second photon is blueshifted as the lowest energy state is occupied. This setup of states leads to a doublepeak feature in a set of two dimensional ...


Yuan H K   2013
Complementary to the recent experimental finding that the orbital magnetic moment is strongly quenched in small Fe clusters [M. Niemeyer, K. Hirsch, V. ZamudioBayer, A. Langenberg, M. Vogel, M. Kossick, C. Ebrecht, K. Egashira, A. Terasaki, T. Möller, B. v. Issendorff, and J. T. Lau, Phys. Rev. Lett. 108, 057201 ...


Thompson James O F   2013
Timeresolved photoelectron imaging was used to investigate the relaxation dynamics of electronically excited aniline in the gasphase following ultraviolet irradiation in the 273266 nm region. We find that at all wavelengths studied, excitation is predominantly to the longlived (>1 ns) S1(ππ(∗)) state, which exhibits ultrafast intramolecular vibrational redistribution on a ...


Ibraguimova L B   2013
The oxygen absorbance was studied at wavelengths 200270 nm in SchumannRunge system behind the front of a strong shock wave. Using these data, the vibrational temperature Tv behind the front of shock waves was measured at temperatures 400010 800 K in undiluted oxygen. Determination of Tv was based on the measurements ...


Accary JB   2013
We investigate the effect of the isomerization rate f on the microscopic mechanisms at the origin of the massive mass transport found in glassformers doped with isomerizing azobenzene molecules that result in surface relief gratings formation. To this end we simulate the isomerization of dispersed probe molecules embedded into a ...


Willey T M   2013
Phthalocyanines, a class of macrocyclic, square planar molecules, are extensively studied as semiconductor materials for chemical sensors, dyesensitized solar cells, and other applications. In this study, we use angular dependent nearedge xray absorption fine structure (NEXAFS) spectroscopy as a quantitative probe of the orientation and electronic structure of H2, Fe, ...


Liu ChunSheng   2013
Unlike on hexagonal graphene where Li atoms tend to cluster, using density functional theory, we demonstrate that Li atoms remain isolated on tetrasymmetrical T graphene due to a nonuniform charge distribution in T graphene. Furthermore, we examine the adsorption of several common gas molecules and find that Lidecorated T graphene ...


D'Adamo Giuseppe   2013
We extend our previously developed coarsegraining strategy for linear polymers with a tunable number n of effective atoms (blobs) per chain [G. D'Adamo et al., J. Chem. Phys. 137, 024901 (2012)] to polymer systems in thermal crossover between the goodsolvent and the θ regimes. We consider the thermal crossover in ...


Kampmann Tobias A   2013
We study the adsorption of semiflexible polymers such as polyelectrolytes or DNA on planar and curved substrates, e.g., spheres or washboard substrates via shortrange potentials using extensive Monte Carlo simulations, scaling arguments, and analytical transfer matrix techniques. We show that the adsorption threshold of stiff or semiflexible polymers on a ...


Richardson Jeremy O   2013
A new method based on an extension of ringpolymer molecular dynamics is proposed for the calculation of thermal correlation functions in electronically nonadiabatic systems. The ringpolymer dynamics are performed using a continuousvariable representation of the electronic states within the mapping approach, such that the electronic and nuclear degrees of freedom ...


Sirjoosingh Andrew   2013
The nuclearelectronic orbital (NEO) method treats electrons and select nuclei quantum mechanically on the same level to extend beyond the BornOppenheimer approximation. Electronnucleus dynamical correlation has been found to be highly significant due to the attractive Coulomb interaction. The explicitly correlated HartreeFock (NEOXCHF) approach includes explicit electronnucleus correlation with Gaussiantype ...


Sirjoosingh Andrew   2013
In the application of the nuclearelectronic orbital (NEO) method to positronic systems, all electrons and the positron are treated quantum mechanically on the same level. Explicit electronpositron correlation can be included using Gaussiantype geminal functions within the variational selfconsistentfield procedure. In this paper, we apply the recently developed reduced explicitly ...


Kawamoto Shuhei   2013
A new method is proposed to estimate the bending rigidity of lipid membranes from molecular dynamics simulations. An external cylindrical guiding potential is used to impose a sinusoidal deformation to a planar membrane. The bending rigidity is obtained from the mean force acting on the cylinder by calibrating against a ...


Seino Junji   2013
In order to perform practical electron correlation calculations, the local unitary transformation (LUT) scheme at the spinfree infiniteorder DouglasKrollHess (IODKH) level [J. Seino and H. Nakai, J. Chem. Phys. 136, 244102 (2012); and ibid. 137, 144101 (2012)], which is based on the locality of relativistic effects, has been combined with ...


Ai BaoQuan   2013
Transport of the finite size spherical Brownian particles is investigated in confined narrow channels with varying crosssection width. Applying the FickJacobs approximation, we obtain the expressions of the particle current, the effective diffusion coefficient, and the coherence level of Brownian transport (the Péclet number). For the case of the biased ...


Gaur Abhijeet   2013
Xray absorption fine structure spectra of five copper(I) thiourea complexes [Cu4(thu)6 (NO3)4 (H2O)4] (1), [Cu4(thu)9 (NO3)4 (H2O)4] (2), [Cu2(thu)6 (SO4) H2O] (3), [Cu2(thu)5 (SO4) (H2O)3] (4), and [Cu(thu)Cl 0.5H2O] (5) have been investigated. Complexes 1 and 3 are supposed to have one type of copper centers in trigonal planar and ...


DenisAlpizar Otoniel   2013
A fourdimensional potential energy surface representing the interaction between He and hydrogen cyanide (HCN) subjected to bending vibrational motion is presented. Ab initio calculations were carried out at the coupledcluster level with single and double excitations and a perturbative treatment of triple excitations, using a quadruplezeta basis set and midbond ...


Ma Q   2013
Since it was developed in 1979, the RobertBonamy (RB) formalism has been widely used in calculating pressure broadened halfwidths and induced shifts for many molecular systems. However, this formalism contains several approximations whose applicability has not been thoroughly justified. One of them is that lines of interest are well isolated. ...


Kosumi Daisuke   2013
Ultrafast excitedstate dynamics of the photosynthetic pigment (Mg)bacteriochlorophyll a and its Znsubstituted form were investigated by steadystate absorption∕fluorescence and femtosecond pumpprobe spectroscopic measurements. The obtained steadystate absorption and fluorescence spectra of bacteriochlorophyll a in solution showed that the central metal compound significantly affects the energy of the Qx state, but ...


Qin Zhengbo   2013
Photoelectron velocitymap imaging spectroscopy has been used to study the reaction of the anionic gold atom with the HR (R = SCH3, OCH3, OH) molecules. The solvated [Au⋯HR]() and inserted [HAuR]() products have been experimentally observed for R = SCH3, whereas only solvated [Au⋯HR]() products were found for R = ...


Mackenzie Rebecca B   2013
Microwave spectra are reported for the C3v symmetric complexes KrSO3 and KrSO3CO. The SC distance in the trimer, 2.871(9) Å, is the same as that previously determined for SO3CO to within the estimated uncertainties. The KrS distances are 3.438(3) Å and 3.488(6) Å in KrSO3 and KrSO3CO, respectively, indicating that ...


Zhao Shuangliang   2013
The direct correlation function (DCF) plays a pivotal role in addressing the thermodynamic properties with nonmeanfield statistical theories of liquid state. This work provides an accurate yet efficient calculation procedure for evaluating the angulardependent DCF of bulk SPC∕E water. The DCF here represented in a discrete angles basis is computed ...


Sarma Rahul   2013
The ability of the osmolyte, trimethylamineNoxide (TMAO), to protect proteins from deleterious effect of urea, another commonly available osmolyte, is wellestablished. However, the molecular mechanism of this counteraction is not understood yet. To provide a molecular level understanding of how TMAO protects proteins in highly concentrated urea solution, we report ...


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