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Methane emissions inventory verification in southern California
Methane (CH4) and carbon monoxide (CO) mixing ratios were measured at an air quality monitoring station near the Mt. Wilson (MW) Observatory in southern California starting in the spring of 2007. Diurnal variation and mixing ratio correlation (R2 = 0.81) were observed. The correlation results observed agree with previous aircraft measurements collected over the greater Los Angeles (LA) metropolitan area. The consistent agreement between CH4 and CO indicates these gases are well-mixed before reaching the sampling site and the emission source contributions of both compounds are reasonably constant. Since CH4 and CO are considered non-reactive on the time scale of dispersion within the LA urban area and their emission sources are likely to be similarly distributed (e.g., associated with human activities) they are subject to similar scales of atmospheric transport and dilution. This behavior allows the relationship of CH4 and CO to be applied for estimation of CH4 emissions using well-documented CO emissions. Applying this relationship a "top-down" CH4 inventory was calculated for LA County based on the measurements observed at MW and compared with the California Air Resources Board (CARB) "bottom-up" CH4 emissions inventory based on the Intergovernmental Panel on Climate Change recommended methodologies. The "top-down" CH4 emissions inventory is approximately one-third greater than CARB's "bottom-up" inventory for LA County. Considering the uncertainties in both methodologies, the different CH4 emissions inventory approaches are in good agreement, although some under and/or uninventoried CH4 sources may exist
Transgene integration - an analysis in autotransgenic Labeo rohita Hamilton (Pisces: Cyprinidae)
Transgenic Labeo rohita founder population was analyzed for the presence of autotransgene having histone 3 promoter and growth hormone (GH) cDNA (LRH3-GHcDNA) or total GH gene (LRH3-GH2.8) by PCR with transgene specific primers. Transgene specific amplification was seen with LRH3-GHcDNA in five out of seven individuals and all three fishes with LRH3-GH2.8, indicating their transgenic nature. Transgene integration was also studied by Southern hybridization of DNA isolated from blood of the transgenic fishes with two different probes (histone 3 promoter and cDNA of L. rohita). Autotransgene integration was confirmed in all PCR positive transgenic individuals. The site of integration of the transgene in the genome of the four transgenic fish could be determined by inverse PCR. Two individuals showed integration at the same site whereas in the remaining two individuals the integration sites were different
Measurement of Rashba and Dresselhaus spin-orbit magnetic fields
Spin-orbit coupling is a manifestation of special relativity. In the
reference frame of a moving electron, electric fields transform into magnetic
fields, which interact with the electron spin and lift the degeneracy of
spin-up and spin-down states. In solid-state systems, the resulting spin-orbit
fields are referred to as Dresselhaus or Rashba fields, depending on whether
the electric fields originate from bulk or structure inversion asymmetry,
respectively. Yet, it remains a challenge to determine the absolute value of
both contributions in a single sample. Here we show that both fields can be
measured by optically monitoring the angular dependence of the electrons' spin
precession on their direction of movement with respect to the crystal lattice.
Furthermore, we demonstrate spin resonance induced by the spin-orbit fields. We
apply our method to GaAs/InGaAs quantum-well electrons, but it can be used
universally to characterise spin-orbit interactions in semiconductors,
facilitating the design of spintronic devices
High Brain Ammonia Tolerance and Down-Regulation of Na+:K+:2Cl- Cotransporter 1b mRNA and Protein Expression in the Brain of the Swamp Eel, Monopterus albus, Exposed to Environmental Ammonia or Terrestrial Conditions
10.1371/journal.pone.0069512PLoS ONE89-POLN
Study of B -> \rho \pi decays at Belle
This paper describes a study of B meson decays to the pseudoscalar-vector
final state \rho\pi using 31.9\times 10^6 B\bar{B} events collected with the
Belle detector at KEKB. The branching fractions B(B^+ \to \rho^0\pi^+) =
(8.0^{+2.3+0.7}_{-2.0-0.7}) \times 10^{-6} and B(B^0 -> \rho^{+-} \pi^{-+}) =
(20.8^{+6.0+2.8}_{-6.3-3.1}) \times 10^{-6} are obtained. In addition, a 90%
confidence level upper limit of B(B^0 \to \rho^0\pi^0) < 5.3 \times 10^{-6}is
reported.Comment: 14 pages, 3 figures, to be submitted to Phys. Lett.
Wnt5a induces ROR1 to complex with HS1 to enhance migration of chronic lymphocytic leukemia cells.
ROR1 (receptor tyrosine kinase-like orphan receptor 1) is a conserved, oncoembryonic surface antigen expressed in chronic lymphocytic leukemia (CLL). We found that ROR1 associates with hematopoietic-lineage-cell-specific protein 1 (HS1) in freshly isolated CLL cells or in CLL cells cultured with exogenous Wnt5a. Wnt5a also induced HS1 tyrosine phosphorylation, recruitment of ARHGEF1, activation of RhoA and enhanced chemokine-directed migration; such effects could be inhibited by cirmtuzumab, a humanized anti-ROR1 mAb. We generated truncated forms of ROR1 and found its extracellular cysteine-rich domain or kringle domain was necessary for Wnt5a-induced HS1 phosphorylation. Moreover, the cytoplamic, and more specifically the proline-rich domain (PRD), of ROR1 was required for it to associate with HS1 and allow for F-actin polymerization in response to Wnt5a. Accordingly, we introduced single amino acid substitutions of proline (P) to alanine (A) in the ROR1 PRD at positions 784, 808, 826, 841 or 850 in potential SH3-binding motifs. In contrast to wild-type ROR1, or other ROR1P→︀A mutants, ROR1P(841)A had impaired capacity to recruit HS1 and ARHGEF1 to ROR1 in response to Wnt5a. Moreover, Wnt5a could not induce cells expressing ROR1P(841)A to phosphorylate HS1 or activate ARHGEF1, and was unable to enhance CLL-cell motility. Collectively, these studies indicate HS1 plays an important role in ROR1-dependent Wnt5a-enhanced chemokine-directed leukemia-cell migration
Effect of Peierls transition in armchair carbon nanotube on dynamical behaviour of encapsulated fullerene
The changes of dynamical behaviour of a single fullerene molecule inside an
armchair carbon nanotube caused by the structural Peierls transition in the
nanotube are considered. The structures of the smallest C20 and Fe@C20
fullerenes are computed using the spin-polarized density functional theory.
Significant changes of the barriers for motion along the nanotube axis and
rotation of these fullerenes inside the (8,8) nanotube are found at the Peierls
transition. It is shown that the coefficients of translational and rotational
diffusions of these fullerenes inside the nanotube change by several orders of
magnitude. The possibility of inverse orientational melting, i.e. with a
decrease of temperature, for the systems under consideration is predicted.Comment: 9 pages, 6 figures, 1 tabl
Testing new physics with the electron g-2
We argue that the anomalous magnetic moment of the electron (a_e) can be used
to probe new physics. We show that the present bound on new-physics
contributions to a_e is 8*10^-13, but the sensitivity can be improved by about
an order of magnitude with new measurements of a_e and more refined
determinations of alpha in atomic-physics experiments. Tests on new-physics
effects in a_e can play a crucial role in the interpretation of the observed
discrepancy in the anomalous magnetic moment of the muon (a_mu). In a large
class of models, new contributions to magnetic moments scale with the square of
lepton masses and thus the anomaly in a_mu suggests a new-physics effect in a_e
of (0.7 +- 0.2)*10^-13. We also present examples of new-physics theories in
which this scaling is violated and larger effects in a_e are expected. In such
models the value of a_e is correlated with specific predictions for processes
with violation of lepton number or lepton universality, and with the electric
dipole moment of the electron.Comment: 34 pages, 7 figures. Minor changes and references adde
Searching for Exoplanets Using a Microresonator Astrocomb
Detection of weak radial velocity shifts of host stars induced by orbiting
planets is an important technique for discovering and characterizing planets
beyond our solar system. Optical frequency combs enable calibration of stellar
radial velocity shifts at levels required for detection of Earth analogs. A new
chip-based device, the Kerr soliton microcomb, has properties ideal for
ubiquitous application outside the lab and even in future space-borne
instruments. Moreover, microcomb spectra are ideally suited for astronomical
spectrograph calibration and eliminate filtering steps required by conventional
mode-locked-laser frequency combs. Here, for the calibration of astronomical
spectrographs, we demonstrate an atomic/molecular line-referenced,
near-infrared soliton microcomb. Efforts to search for the known exoplanet HD
187123b were conducted at the Keck-II telescope as a first in-the-field
demonstration of microcombs
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