2,501 research outputs found
Cumbria and the northern Pennines
Carboniferous rocks within the Cumbria and northern Pennines region are bound by
the Maryport–Stublick–Ninety Fathom Fault System, which forms the northern
boundary of the Lake District and Alston blocks (Fig. 12.1). In the Pennines, the
succession occupies the Alston and Askrigg blocks and the intervening Stainmore
Trough, a broadly east-west trending graben. Carboniferous strata also flank the Lake
District High, occurring at outcrop in north Cumbria, Furness and Cartmel (south
Cumbria) and the Vale of Eden, and in the subsurface in west Cumbria. The Askrigg
Block succession is separated from that of the Craven Basin (Chapter 11), to the
south, by the Craven Fault System
Evaluation of a New Technique for Recording the Direction of Flight of Mosquitoes(Diptera:Culicidae) in the Field
In a study in the Gambia on the relationship between wind direction and the direction of flight of mosquitoes electric grids were used as screens in conjunction with suction traps. Mosquitoes contacting or attempting to fly through the grids were electrocuted. The screening efficiency of the grids was estimated to be 75-80%, and the grids had no demonstrable effect on wind speed. The traps were set up in pairs with their mouths at ground level, one trap in each pair being screened on the upwind and the other on the downwind side. In this way, the mosquitoes could be segregated into those that were flying predominantly upwind and predominantly downwind, respectively. The results indicated that some 64% were flying upwind at this level, but this proportion varied considerably over a period of days, with nightly extremes of 87 and 43%; these was little difference between species. This variation was not correlated with wind speed, but there was some evidence that the presence of moonlight led wind speed, but there was evidence that presence of moonlight led to a greater degree of upwind flight
Clarifying Some Remaining Questions in the Anomaly Puzzle
We discuss several points that may help to clarify some questions that remain
about the anomaly puzzle in supersymmetric theories. In particular, we consider
a general N=1 supersymmetric Yang-Mills theory. The anomaly puzzle concerns the
question of whether there is a consistent way to put the R-current and the
stress tensor in a single supercurrent, even though in the classical theory
they are in the same supermultiplet. As is well known, the classically
conserved supercurrent bifurcates into two supercurrents having different
anomalies in the quantum regime. The most interesting result we obtain is an
explicit expression for the lowest component of one of the two supercurrents in
4-dimensional spacetime, namely the supercurrent that has the energy-momentum
tensor as one of its components. This expression for the lowest component is an
energy-dependent linear combination of two chiral currents, which itself does
not correspond to a classically conserved chiral current. The lowest component
of the other supercurrent, namely, the R-current, satisfies the Adler-Bardeen
theorem. The lowest component of the first supercurrent has an anomaly that we
show is consistent with the anomaly of the trace of the energy-momentum tensor.
Therefore, we conclude that there is no consistent way to put the R-current and
the stress tensor in a single supercurrent in the quantized theory. We also
discuss and try to clarify some technical points in the derivations of the
two-supercurrents in the literature. These latter points concern the
significance of infrared contributions to the NSVZ beta-function and the role
of the equations of motion in deriving the two supercurrents.Comment: 22 pages, no figure. v2: minor changes. v3: sections re-organized.
new subsections (IVA, IVB) added. references adde
Semiclassical interferences and catastrophes in the ionization of Rydberg atoms by half-cycle pulses
A multi-dimensional semiclassical description of excitation of a Rydberg
electron by half-cycle pulses is developed and applied to the study of energy-
and angle-resolved ionization spectra. Characteristic novel phenomena
observable in these spectra such as interference oscillations and semiclassical
glory and rainbow scattering are discussed and related to the underlying
classical dynamics of the Rydberg electron. Modifications to the predictions of
the impulse approximation are examined that arise due to finite pulse
durations
Integrated use of Biochar: A tool for improving soil and wheat quality of degraded soil under wheat-maiza cropping pattern
Wheat quality, nutrient uptake and nutrient use efficiency are significantly influenced by nutrient sources and application rate. To investigate the integrative effect of biochar, farmyard manure (FYM) and nitrogen (organic and inorganic soil amendments) in a wheat-maize cropping system, a two year study was designed to assess the interactive outcome of biochar, FYM and nitrogenous fertilizer on wheat nitrogen (N) parameters and associated soil quality parameters. Three levels of biochar (0, 25 and 50 t ha-1), two levels of FYM (5 and 10 t ha-1) and two levels of nitrogen fertilizer (60 and 120 kg ha-1) were used in the study. Biochar application displayed a significantly increased in wheat leaf, stem, straw and grain N content; grain and total N-uptake and grain protein content by 24, 20, 24, 56, 50, 17 and 20% respectively. Similarly, biochar application significantly increased soil total N (TN) and soil mineral N (SMN) by 63 and 40% respectively in second year. FYM application increased grain, leaf and straw N content by 20, 19.5 and 18% respectively, and increased total N-uptake and grain protein content by 49 and 19% respectively. FYM increased soil TN and SMN by 63 and 32% in both the years of the experiment. Mineral N application increased soil TN by over a half and SMN by a third, and grain protein content increased 16%. In contrast, nitrogen use efficiency (NUE) decreased for all amendments relative to the control. However, biochar treated plots improved NUE by 38% compared to plots without biochar. In conclusion, this field experiment has illustrated the potential of biochar to bring about short-term benefits in wheat and soil quality parameters in wheat-maize cropping systems. However, the long-term benefits remain to be quantified
Impact of rest-redistribution on fatigue during maximal eccentric knee extensions
Redistributing long inter-set rest intervals into shorter but more frequent rest intervals generally maintains concentric performance, possibly due to improved energy store maintenance. However, eccentric actions require less energy than concentric actions, meaning that shorter but more frequent sets may not affect eccentric actions to the same degree as concentric actions. Considering the increased popularity of eccentric exercise, the current study evaluated the effects of redistributing long inter-set rest periods into shorter but more frequent rest periods during eccentric only knee extensions. Eleven resistance-trained men performed 40 isokinetic unilateral knee extensions at 60°·s-1 with 285 s of total rest using traditional sets (TS; 4 sets of 10 with 95 s inter-set rest) and rest-redistribution (RR; 20 sets of 2 with 15 s inter-set rest). Before and during exercise, muscle oxygenation was measured via near-infrared spectroscopy, and rating of perceived exertion (RPE) was recorded after every 10th repetition. There were no differences between protocols for peak torque (RR, 241.58±47.20 N; TS, 231.64±48.87 N; p=0.396) or total work (RR, 215.26±41.47 J; TS, 209.71±36.02 J; p=0.601), but moderate to large effect sizes existed in later repetitions (6,8,10) with greater peak torque during RR (d=0.66-1.19). For the entire session, RR had moderate effects on RPE (RR, 5.73±1.42; TS, 6.09±1.30; p=0.307; d=0.53) and large effects on oxygen saturation (RR, 5857.4±310.0; TS, 6495.8±273.8; p=0.002, d=2.13). Therefore, RR may maintain peak torque or total work during eccentric exercise, improve oxygen utilization at the muscle, and reduce the perceived effort
Turner et al. Reply to "Emergence of the Same Successful Clade among Distinct Populations of emm89 Streptococcus pyogenes in Multiple Geographic Regions"
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NPARSEC : NTT Parallaxes of Southern Extremely Cool objects. Goals, targets, procedures and first results
The discovery and subsequent detailed study of T dwarfs have provided many surprises and pushed the physics and modelling of cool atmospheres in unpredicted directions. Distance is a critical parameter for studies of these objects to determine intrinsic luminosities, test binarity and measure their motion in the Galaxy. We describe a new observational programme to determine distances across the full range of T-dwarf subtypes using the New Technology Telescope (NTT)/SOFI telescope/instrument combination. We present preliminary results for ten objects, five of which represent new distances.Peer reviewe
Indirect Exchange Interaction between two Quantum Dots in an Aharonov-Bohm Ring
We investigate the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction between
two spins located at two quantum dots embedded in an Aharonov-Bohm (AB) ring.
In such a system the RKKY interaction, which oscillates as a function of the
distance between two local spins, is affected by the flux. For the case of the
ferromagnetic RKKY interaction, we find that the amplitude of AB oscillations
is enhanced by the Kondo correlations and an additional maximum appears at half
flux, where the interaction is switched off. For the case of the
antiferromagnetic RKKY interaction, we find that the phase of AB oscillations
is shifted by pi, which is attributed to the formation of a singlet state
between two spins for the flux value close to integer value of flux.Comment: 10 pages, 5 figure
Universality of the Operator Product Expansions of SCFT_4
We study the operator product algebra of the supercurrent J and Konishi
superfield K in four-dimensional supersymmetric gauge theories. The Konishi
superfield appears in the JJ OPE and the algebra is characterized by two
central charges c and c' and an anomalous dimension h for K. In free field
(one-loop) approximation, c~3N_v+N_\chi and c'~N_\chi, where N_v and N_\chi
are, respectively, the number of vector and chiral multiplets in the theory. In
higher order c, c' and h depend on the gauge and Yukawa couplings and we obtain
the two-loop contributions by combining earlier work on c with our own
calculations of c'. The major result is that the radiative corrections to the
central charges cancel when the one-loop beta-functions vanish, suggesting that
c and c' (but not h) are invariant under continuous deformations of
superconformal theories. The behavior of c and c' along renormalization group
flows is studied from the viewpoint of a c-theorem.Comment: LaTeX file, 11 pages, no figur
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