Carbon nanotubes were suspended in carbon tetrachloride and placed in magnetic fields of <80.0 kOe at 310 K. Scanning electron microscopy showed that a single and free nanotube was oriented with the tube axis parallel to the fields. From the Boltzmann distribution of tube directions, the anisotropy of susceptibilities parallel (χ∥) and perpendicular (χ⊥) to the tube axis is estimated to be χ∥ − χ⊥ ∼ (9 ± 5) × 10-6 emu per mole of carbon atoms (χ⊥ < χ∥ < 0).

Phonon modes in crystals can have angular momenta in general. It nevertheless cancels in equilibrium when the time-reversal symmetry is preserved. In this paper we show that when a temperature gradient is applied and heat current flows in the crystal, the phonon distribution becomes off-equilibrium, and a finite angular momentum is generated by the heat current. This mechanism is analogous to the Edelstein effect in electronic systems. This effect requires crystals with sufficiently low crystallographic symmetries, such as polar or chiral crystal structures. Because of the positive charges of the nuclei, this phonon angular momentum induces magnetization. In addition, when the crystal can freely rotate, this generated phonon angular momentum is converted to a rigidbody rotation of the crystal, due to the conservation of the total angular momentum. Furthermore, in metallic crystals, the phonon angular momentum will be partially converted into spin angular momentum of electrons.PACS numbers: 63.20.-e, 81.05.Cy, 81.05. Ea, Conversions between the magnetization and the mechanical generation can be realized in various ways, such as Einstein-de Haas effect [1] and Barnett effect [2]. In the Einstein-de Haas effect, when the sample is magnetized by the external magnetic field, the sample rotates due to the conservation of the angular momentum. On the other hand, in the Barnett effect, a rotation of the sample induces magnetization. The key mechanism of these effects is the spin-rotation coupling, which relates electronic spins with a mechanical rotation [3]. In addition, spin-rotation coupling also enables mechanical generation of spin current in various systems [4][5][6]. In these effects, rotational motions of phonons in solids are important, and in this context an phonon angular momentum is formulated theoretically [7-9].Here we focus on the phonon angular momentum introduced in [7], which represents rotational motions of the nuclei within each phonon mode. In crystals with timereversal symmetry, i.e. those without magnetic field or magnetization, the phonon angular momentum of each mode is an odd function of the wavevector k and the total angular momentum vanishes in equilibrium due to cancellation between phonons with the wavevector k and those with −k. Meanwhile, one can expect that this cancellation goes away by driving the system off the equilibrium, and nonzero phonon angular momentum is induced. In this letter, to theoretically show this scenario, we consider a crystal with a finite heat current, and show a nonzero total phonon angular momentum in the crystal due to its nonequilibrium phonon distribution. The crystal symmetry should be sufficiently low to allow this effect, and in particular the inversion symmetry should be absent. We calculate the phonon angular momentum generated by heat current for the wurtzite GaN as an example of polar systems and the Te (tellurium) and Se (selenium) as examples of chiral systems. For wurtzite GaN, we calculate the phonon properties by using the valence force field model ...

Src tyrosine kinase plays key roles in signal transduction following growth factor stimulation and integrinmediated cell-substrate adhesion. Since src-signal transduction defects are implicated in a multitude of human diseases, we have sought to develop new ways to identify small molecule inhibitors using a yeast-based, activatedsrc over-expression system. In the present study, we describe the identi®cation of a unique src-signal transduction inhibitor, UCS15A. UCS15A was found to inhibit the src speci®c tyrosine phosphorylation of numerous proteins in v-src-transformed cells. Two of these phosphoproteins were identi®ed as bona-®de src substrates, cortactin and Sam68. UCS15A diered from conventional src-inhibitors in that it did not inhibit the tyrosine kinase activity of src. In addition, UCS15A appeared to dier from src-destabilizing agents such as herbimycin and radicicol that destabilize src by interfering with Hsp90. Our studies suggest that UCS15A exerted its src-inhibitory eects by a novel mechanism that involved disruption of protein-protein interactions mediated by src. One of the biological consequences of src-inhibition by UCS15A was its ability to inhibit the bone resorption activity of osteoclasts in vitro. These data suggest that UCS15A may inhibit the bone resorption activity of osteoclasts, not by inhibiting src tyrosine kinase activity, but by disrupting the interaction of proteins associated with src, thereby modulating downstream events in the src signal transduction pathway. Oncogene (2001Oncogene ( ) 20, 2068Oncogene ( ± 2079

The Asian citrus psyllid Diaphorina citri Kuwayama (Hemiptera: Sternorrhyncha: Psylloidea: Liviidae) is an important pest of citrus species worldwide because it transmits Candidatus Liberibacter spp. ( Alphaproteobacteria ), the causative agents of an incurable citrus disease known as huanglongbing or greening disease. Diaphorina citri possesses a vertically-transmitted intracellular symbiont, Candidatus Profftella armatura ( Betaproteobacteria ), which produces diaphorin, a polyketide that is significantly toxic to mammalian cells. Diaphorin is an analog of pederin, a defensive polyketide in the body fluid of Paederus rove beetles (Coleoptera: Staphylinidae) that deters predators. In the present study, as a first step to assess the possibility that diaphorin is toxic to biological control agents, we assayed diaphorin activities against insects and fungi. The target cells and organisms were (a) the Sf9 cell line derived from the fall armyworm moth Spodoptera frugiperda (Lepidoptera: Noctuidae), (b) the pea aphid Acyrthosiphon pisum (Hemiptera: Sternorrhyncha: Aphidoidea: Aphididae), a phloem sap-sucking insect that is closely related to psyllids, (c) the Asian lady beetle Harmonia axyridis (Coleoptera: Coccinellidae), one of the major predators of D . citri , and (d) the budding yeast Saccharomyces cerevisiae (Ascomycota: Saccharomycetes) as a model of fungal pathogens. For a comparison, we also evaluated pederin activities. The results of our analyses revealed the following: (1) Diaphorin and pederin are significantly toxic to the tested insects and yeast; (2) Their toxicities vary widely among the target cells and organisms; (3) Diaphorin is generally less toxic than pederin; (4) The toxicities of diaphorin and pederin are considerably different in the Sf9 insect cell line and S . cerevisiae , but similar in A . pisum and H . axyridis ; and (5) The amount of diaphorin contained in D . citri is toxic to all of the tested cells and organisms, suggesting that this polyketide is potentially harmful for biological control agents.

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We theoretically investigate spin current and magnetic response induced by the twisting phonon mode in carbon nanotubes via the spin-rotation coupling. An effective magnetic field due to the twisting mode induces both spin and orbital magnetizations. The induced spin and orbital magnetizations have both radial and axial components. We show that AC pure spin current is generated by the twisting phonon mode. The magnitude of the spin current and orbital magnetization for a (10,10) armchair nanotube is estimated as an example. We find that the AC pure spin current is detectable in magnitude when the frequency of the twisting mode is of the order of GHz, and that the orbital magnetization is found to be larger than the spin magnetization.PACS numbers: 61.48. De, Introduction. Carbon nanotubes (CNTs) have been studied extensively, and today various interesting physical characters of CNTs have been reported. CNTs can be regarded as rolls of graphene sheets, and therefore their electronic bands are closely related with those of graphene. In graphene, the electronic bands form linear dispersion called a Dirac cone. By rolling the graphene into a CNT, the band structure becomes a metal or semiconductor depending on its chirality. From the viewpoint of spin transport, the spin-orbit interaction of CNT is so weak that spin current cannot be generated for CNT alone by usual methods which require strong spin-orbit interaction.