Stress buildup in the Himalaya

The seismic cycle on a major fault involves long periods of elastic strain and stress accumulation, driven by aseismic ductile deformation at depth, ultimately released by sudden fault slip events. Coseismic slip distributions are generally heterogeneous with most of the energy being released in the rupture of asperities. Since, on the long term, the fault's walls generally do not accumulate any significant permanent deformation, interseismic deformation might be heterogeneous, revealing zones of focused stress buildup. The pattern of current deformation along the Himalayan arc, which is known to produce recurring devastating earthquakes, and where several seismic gaps have long been recognized, might accordingly show significant lateral variations, providing a possible explanation for the uneven microseismic activity along the Himalayan arc. By contrast, the geodetic measurements show a rather uniform pattern of interseismic strain, oriented consistently with long-term geological deformation, as indicated from stretching lineation. We show that the geodetic data and seismicity distribution are reconciled from a model in which microseismicity is interpreted as driven by stress buildup increase in the interseismic period. The uneven seismicity pattern is shown to reflect the impact of the topography on the stress field, indicating low deviatoric stresses (<35 MPa) and a low friction (<0.3) on the Main Himalayan Thrust. Arc-normal thrusting along the Himalayan front and east-west extension in southern Tibet are quantitatively reconciled by the model

Jacobi Crossover Ensembles of Random Matrices and Statistics of Transmission Eigenvalues

We study the transition in conductance properties of chaotic mesoscopic cavities as time-reversal symmetry is broken. We consider the Brownian motion model for transmission eigenvalues for both types of transitions, viz., orthogonal-unitary and symplectic-unitary crossovers depending on the presence or absence of spin-rotation symmetry of the electron. In both cases the crossover is governed by a Brownian motion parameter {\tau}, which measures the extent of time-reversal symmetry breaking. It is shown that the results obtained correspond to the Jacobi crossover ensembles of random matrices. We derive the level density and the correlation functions of higher orders for the transmission eigenvalues. We also obtain the exact expressions for the average conductance, average shot-noise power and variance of conductance, as functions of {\tau}, for arbitrary number of modes (channels) in the two leads connected to the cavity. Moreover, we give the asymptotic result for the variance of shot-noise power for both the crossovers, the exact results being too long. In the {\tau} \rightarrow 0 and {\tau} \rightarrow \infty limits the known results for the orthogonal (or symplectic) and unitary ensembles are reproduced. In the weak time-reversal symmetry breaking regime our results are shown to be in agreement with the semiclassical predictions.Comment: 24 pages, 5 figure

Hormonal regulation of the lag phase in seeded and seedless grapes (Vitis vinifera L.)

The first rapid growth phase of grape berry (stage I) was associatecl with high levels of auxin-like substances ancl low levels of growth inhibitory substances. In the lag phase (stage II) of berry clevelopment high levels of growth inhibitors and low levels of growth promotors were observed. The berry growth in the post-lag phase (st;:ige III) was generally associated with higher levels of gibberellin-like substances.Die hormonale Steuerung der Phase des verlangsamten Beerenwachstums bei samenhaltigen und samenlosen Reben (Vitis vinifera L.)In der ersten Phase des raschen Beerenwachstums (I) lagen hohe Konzentrationen auxinartiger Substanzen und niedrige Konzentrationen wachstumshemmender Substanzen vor. Während der anschließenden Phase des verlangsamten Beerenwachstums (II) wurden hohe Konzentrationen von Wachstumshemmern und niedrige Konzentrationen von wachstumsfördernden Substanzen festgestellt. Das erneut beschleunigte Beerenwachstum in der darauf folgenden Phase (III) war im allgemeinen mit erhöhten Konzentrationen gibberellinartiger Substanzen verbunden

Changes in the rate of photosynthesis and respiration in leaves and berries of Vitis vinifera grapevines at various stages of berry development

The photosynthetic and respiratory activity of leaves and berries was measured in Pusa Seedless and Tas (seeded) cultivars with WARBURG technique at pre-lag, lag and post-lag phases of berry development. The fourth leaf opposite to the bunch was found to be the ideal material for further study by virtue of having the highest photosynthetic rate as compared to other leaves at düferent positions.The rate of the leaf photosynthesis was found to increase up to the 4th week of berry development, thereafter a decline was noticed till harvest in both the cultivars. The rate of leaf respiration remained almost parallel throughout the experiment in both the cultivars.The peak photosynthetic activity of berries was recorded at the 4th week of berry development with a gradual reduction in the subsequent weeks in both the cultivars. Berries of both the cultivars showed a decline in their respiratory activity, which was greater during the first growth period.The main conclusions which can be drawn from the present investigation are that, firstly, photosynthates synthesized by green berries hardly make any contribution to the growth of the berries. Secondly, presence or absence of seeds do not have any effect on the photosynthetic and respiratory activity of berries and leaves.Veränderungen der Photosynthese- und Respirationsintensität bei Blättern und Beeren von Reben (Vitis vinifera) während verschiedener Entwicklungsphasen der BeerenBei den Blättern und Beeren der Rebensorten Pusa Seedless und Tas (kernhaltig) wurden mit Hilfe der Warburg-Technik die Photosynthese-und Respirationsintensität zur Zeit des ersten raschen Beerenwachstums (Phase I), des verlangsamten Wachstums (II) und des erneut beschleunigten Beerenwachstums (III) bestimmt. Für weiterführende Untersuchungen erwies sich das 4. Blatt, gegenüber der Traube, als optimal geeignet, da es im Vergleich zu den verschiedenen anders inserierten Blättern die höchste Photosyntheseintensität besitzt.Bis zur 4. Woche der Beerenentwicklung wurde bei beiden Sorten ein Anstieg, danach bis zur Ernte eine Abnahme der Photosynthese im Blatt gefunden. Die Respiration der Blätter zeigte bei beiden Sorten während des Versuchszeitraumes fast keine Veränderungen.Bei der Photosynthese der Beeren wurde in der 4. Woche ihrer Entwicklung ein Maximum, in den folgenden Wochen ein allmählicher Rückgang festgestellt. Die Beeren beider Sorten zeigten, vor allem in der ersten Wachstumsphase, einen stetigen Rückgang ihrer Respirationsintensität.Aus den Untersuchungen kann gefolgert werden, daß die in den grünen Beeren selbst gebildeten Photosynthate keinen nennenswerten Beitrag zum Beerenwachstum leisten und daß ferner durch das Vorhandensein oder Fehlen von Samen die Photosynthese- und Respirationsaktivität von Beeren und Blättern nicht beeinflußt wird

Effect of a magnetic flux on the critical behavior of a system with long range hopping

We study the effect of a magnetic flux in a 1D disordered wire with long range hopping. It is shown that this model is at the metal-insulator transition (MIT) for all disorder values and the spectral correlations are given by critical statistics. In the weak disorder regime a smooth transition between orthogonal and unitary symmetry is observed as the flux strength increases. By contrast, in the strong disorder regime the spectral correlations are almost flux independent. It is also conjectured that the two level correlation function for arbitrary flux is given by the dynamical density-density correlations of the Calogero-Sutherland (CS) model at finite temperature. Finally we describe the classical dynamics of the model and its relevance to quantum chaos.Comment: 5 pages, 4 figure

Oblique Convergence in the Himalayas of Western Nepal Deduced from Preliminary Results of GPS Measurements

A GPS network consisting of 29 sites was installed in central and western Nepal, with measurements taken in 1995 and partial remeasurements in 1997. Data suggest 15 +/−5 mm/yr of N180° convergence between the Higher Himalayas and India, a result that is consistent with N‐S shortening across the arcuate shape of the Nepalese Himalayas and an oblique underthrusting of the Indian crust below the High Himalayas of western Nepal. A 4 +/−3 mm/year E‐W extension and deviation of the principal shortening axes are inferred east of 83°E, where Quaternary faults (Darma‐Bari Gad fault system and Thakkhola graben) delineate a crustal wedge. This wedge is located on the SE projection of the Karakorum fault and may segment the Himalayan thrust belt. The convergence between the outer belt of western Nepal and India is less than 3 mm/yr, an attenuation consistent with creep on a dislocation locked beneath the Lesser Himalayas. A preliminary model suggests that this N 120°E striking dislocation is affected by a 19 mm/yr thrust component and a 7 mm/yr right lateral component

Water quality surrounding to MSW dumps of Raipur city-A case study

In India, urbanization and rapid population growth have led to degradation of environment, by increased rate of exploitation of natural resources and generation of municipal solid wastes (MSW). Municipal Solid Waste (MSW) disposal is a big problem for most of the towns in developing countries. In India dumping of MSW on low laying area is the common practice in most of the towns. The dumping of waste in uncontrolled manner creates many kinds of problems for the surrounding environment. Ground water pollution is one of the serious effects of the MSW dumping. The assessment of impacts on ground water sources near to MSW dumps is of considerable importance in management and disposal of solid waste. The leachate may greatly affect the ground water sources near to the dumpsites. In the present study an attempt has been made to investigate the extent of impact on ground water sources namely open wells, shallow tube wells (depth less than 30 m) and deep tube wells (depth more than 50 m).&nbsp; The pollution status is also monitored at varying distances from the solid waste dumping sites to investigate the trend of leachate movement in the subsoil. Water samples from different sources at different locations are assessed for physical, chemical and biological properties.&nbsp

Seasonal variation in composition and characteristics of indian municipal solid waste –A case study

In developing countries like India, rapid urbanization and uncontrolled population growth have lead to the socio-environmental problem of ill-managed municipal solid waste. Evaluating the characteristics of municipal solid waste is an important aspect of MSWM because the selection of effective management strategies depends on the types and variation in the characteristics of the waste to be managed. The focus of the present paper is to determine the variation in composition as well as characteristics of municipal solid waste for Indian conditions. A case study is presented for Raipur city to determine the seasonal variation in waste characteristics. The seasonal variation in characteristics of MSW was found to be in a wide range of 4-125 %, so for comprehensive management of this MSW, a proper combination of recycling and recovery, composting, energy generation and dumping on land should be adopted.&nbsp

Electronic conduction in a three-terminal molecular transistor

The electronic conduction of a novel, three-terminal molecular architecture, analogous to a heterojunction bipolar transistor is studied. In this architecture, two diode arms consisting of donor-acceptor molecular wires fuse through a ring, while a gate modulating wire is a \pi-conjugated wire. The calculated results show the enhancement or depletion mode of a transistor by applying a gate field along the positive or negative direction. A small gate field is required to switch on the current in the proposed architecture. The changes in the electronic conduction can be attributed to the intrinsic dipolar molecular architecture in terms of the evolution of molecular wavefunctions, specifically the one associated with the terphenyl group of the modulating wire in the presence of the gate field.Comment: 13 pages, 5 figure