ALBERT

Notes: Molecular investigation of the process of cold acclimation in woody plants has been limited by the superimposition of dormancy-related events on the process of cold tolerance development. To address this limitation, we have used the grape Vitis labruscana L. ev. Concord to develop a system in which the developmental programme of dormancy can be induced seperately from cold acclimation. Using this system we have characterized differential accumulation of several proteins in grape buds during the normally superimposed endodormancy and cold acclimation programmes, and in buds which have entered only the endodormancy programme. A set of 47 kD proteins accumulated during endodormancy without cold acclimation to a level similar to that found in endodormant and cold-acclimated buds, but without any associated increase in bud cold-acclimation level. However, a 27 kD LEA-like protein accumulated only in cold acclimated buds. We conclude that expression of the 47 kD glycoprotein is endodormancy-related, but is not strictly related to the development of cold acclimation, while the 27 kD protein appears to be more specific to cold acclimation. In addition to strengthening the association of LEA-like proteins with cold acclimation, this system allows more specific assessment of cold acclimation-associated phenomena in overwintering buds.

Notes: A cDNA clone encoding an isoform of the plasma membrane H+-ATPase was isolated from Nicotiana tabacum. The steady-state plasma membrane H+-ATPase message levels were the same in unadapted tobacco cells and tobacco cells adapted to 428 mol m−3 NaCl. When cells adapted to 428 mol m−3 NaCl maintained in the absence of NaCl (deadapted) for an excess of 100 passages were exposed to 400 mol m−3 NaCl for 24 h, there was an increased accumulation of plasma membrane H+-ATPase message. The NaCl responsiveness of the deadapted cells was dependent upon the growth cycle stage. Alterations in the levels of plasma membrane FT-ATPase message during the growth cycle support a role for the H+-ATPase in cell growth. These results document the induction by NaCl of plasma membrane FT-ATPase message accumulation in tobacco cells, and suggest that enhanced expression of the plasma membrane FT-ATPase has a role in the short term response of cells of NaCl, but is not necessarily involved in long-term adaptation.

Notes: We have investigated the shear-wave polarization anisotropy in the north-eastern Japan arc by using waveforms from many local earthquakes at various depths. We used a cross-correlation method to detect the shear-wave splitting. For intermediate-depth and deep events, the observed fast shear-wave oscillation directions (FSODs) are oriented parallel to the dip direction of the slab at the western stations, while they are oriented perpendicular to the dip direction at the eastern stations. These observations indicate that significant anisotropy exists in the mantle wedge, and that its nature is quite different between the eastern and the western parts.

Notes: In order to understand the causal relation between postglacial rebound and earthquakes, a simple disc load model is used to: (1) calculate stresses induced in the lithosphere and mantle by glacial loading, melting and postglacial rebound; and (2) evaluate the effect of glacial loading/rebound on the failure potential for earthquakes in the upper crust. the dependence of the failure potential and the actual mode of failure on the coefficient of friction, the ambient tectonic stress magnitude/direction, the stress due to the overlying rocks, and lithospheric thickness are investigated. Prominent features of this paper are the inclusion of: (1) a viscoelastic mantle and thus the migration of stress; and (2) the ambient tectonic stress and overburden stress contributions in the calculation of the total stress field.It is assumed that, throughout the Earth, there are optimally oriented pre-existing virtual faults that are initially close to but not at failure; thus, a time-dependent quantity called dFSM (related to the Coulomb-Mohr failure criterion) can be defined such that a negative value of dFSM would advocate faulting or earthquake activities whereas a positive value of dFSM would promote stability.The results indicate that, under all combinations of tectonic stress magnitude and overburden stress, crustal loading promotes fault stability directly underneath the load.Upon the removal of the load, thrust faulting is predicted within the ice margin if the horizontal stress (Sh) induced by the overburden is greater than or equal to the vertical component (Sv) of the overburden stress (1, where =Sh/Sv). Under this condition, theory predicts that faulting or earthquake activity should have reached a maximum immediately after deglaciation.If the horizontal stress induced by the overburden is less than the vertical component of the overburden stress (〉1), then theory predicts fault stability within the ice margin.The theory predicts fault instability both north and south of the ice margin. the mode of failure, however, is completely determined by the value of The trade-off between the tectonic stress magnitude and the overburden stress parameter () is also investigated. It is shown that a larger tectonic stress magnitude can be used to compensate a smaller value of the results of this analysis show that variations in the coefficient of friction, lithospheric thickness and a ductile zone below the upper crust do not significantly affect the above conclusions.

Notes: A remarkable later phase has been detected in seismograms between P- and S-wave arrivals at epicentral distances of about 150 km or more for events occurring in the north-eastern Japan arc. The characteristics of this phase support an interpretation as an sP phase at small epicentral distances, an upgoing S wave from the focus which is then reflected and converted to a P wave at the Earth's surface, diving into the Earth again, and finally reaching the observation stations. The arrival-time difference between this phase and the first P wave is very sensitive to the focal depths of events, and is useful for accurate estimation of the focal depths of those events, in a similar way to using teleseismic depth phases of pP and sP. The utilization of this phase has the advantage of yielding estimates of focal depths for relatively small magnitude events that do not have enough energy to generate teleseismic waves. By using the observed sP phases at small epicentral distances, shallow events beneath the Pacific Ocean in the north-eastern Japan arc, whose focal depths are poorly constrained by the land seismograph network of Tohoku University, have been relocated. The estimated hypocentre distribution, together with the focal mechanism solutions of some of the events, shows that the Pacific plate beneath this region subducts at an extremely low dip angle of less than 10d̀ for the first descent to about 20 km depth and then gradually becomes a steeper dip angle of about 30d̀ at depths deeper than 30 km.

Notes: In order to understand the causal relation between postglacial rebound and earthquakes, a realistic ice and water load model is used to (1) calculate stresses induced in the lithosphere and mantle by glacial loading, melting and postglacial rebound and (2) evaluate the effect of glacial loading/rebound on the failure potential for earthquakes in the upper crust. The dependence of both the failure potential and the actual mode of failure on the ambient tectonic stress magnitude, the overburden stress, and lithospheric properties are investigated. Prominent features of this analysis are the inclusion of (1) a viscoelastic mantle and thus the migration of stress, and (2) the ambient tectonic stress and overburden stress contributions in the calculation of the total stress field.The spatio-temporal calculations, by a finite-element technique, of upper-crustal stresses and the failure potential for earthquakes indicate that fault stability is invariably enhanced directly beneath the load. For the case where stresses induced by the overburden are such that the horizontal component (Sh) is greater than or equal to the vertical component (Sv) (ζ≥ 1, where ζ= Sh/Sv), the model predicts the onset of thrust faulting and maximum earthquake activities soon after deglaciation is complete (when rebound rates are at a maximum). Observational data support this prediction. Since that time, rebound stresses have been decreasing in magnitude, but they continue to act as a trigger mechanism for optimally oriented pre-existing faults that are otherwise on the verge of failure. If one limits the existence of such faults to lie within the pre-weakened zones of eastern Canada, then the spatial distribution of current earthquakes can also be explained.Perturbations to the magnitude of the tectonic stress components or lithospheric properties do not affect, to any significant extent, the above conclusions.

Notes: Juice and seeds from 16 cultivars of mature pummelo fruits were analyzed for limonoid content. Pummelo juice contained an average of 18 ppm limonin and 29 ppm total limonoid glucosides. Compared to other juices, ptmnnelo contained very high concentrations of limonin and very low concentrations of limonoid glucosides. Limonin, nomilin, obacunone and trace amounts of deacetyhromilin were found in pummelo seeds. The 17–β-D-glucopyranoside derivatives (glucosides) of nomilin, nomilinic acid and obacunone were also present. Total limonoid aglycone concentration in the seeds ranged from 773 ppm to 9,900 ppm and total limonoid glucosides ranged from 130 ppm to 1,912 ppm.

Notes: Polygalacturonase, a softening enzyme, influenced the development of physiologically injured fruit treated with vapor heat. Development of a nondestructive method to identify injured fruit was studied. X-ray computed tomography (CT), and 1H-MRI, applied in the medical profession and for food analyses, were investigated for this purpose. Results showed that the X-ray CT, image analyses of the MRI differentiated between normal and injured fruit. The possibility of developing a nondestructive analysis using this technology is suggested.