Toxicological studies on Helicoverpa armigera in pigeonpea growing in Vidarbha region of Maharashtra, India

Insecticide resistance level in pigeonpea pod borer, Helicoverpa armigera (Hubner) to technical grade insecticides collected from major pigeonpea growing districts of Vidarbha viz., Akola, Amravati, Buldhana, Yavatmal and Washim was worked out. LDP indicated LD50 of Cypermethrin in the range of 1.402 to 9.209 ppm with maximum in Yavatmal (9.209 ppm); LD90 within range of 6.021 to 18.427 ppm. LD50 of Quinalphos in the range of 1.303 to 4.789 ppm with maximum in Yavatmal (4.789 ppm); LD90 within range of 3.150 to 14.194 ppm.LD50 of Methomyl in the range of 1.297 to 3.792 ppm with maximum in Yavatmal (3.792 ppm); LD90 within range of 4.993 to 16.737 ppm.LD50 of Indoxacarb in the range of 0.521 to 2.709 ppm with maximum in Yavatmal (2.709 ppm); LD90 within range of 2.819 to 20.947 ppm.LD50 of Spinosad in the range of 0.713 to 2.408 ppm with maximum in Buldhana (2.408 ppm); LD90 within range of 6.413 to 18.349 ppm. The resistance level is visibly high in cypermethrin, moderate to indoxacarb, quinalphos, spinosad and low to methomyl; Yavatmal and Washim strains expressed higher resistance level to cypermethrin, quinalphos and methomyl, whereas Yavatmal and Buldhana strains expressed higher resistance level to indoxacarb and spinosad. The investigation will help to track resistence level in Helicoverpa armigera to different groups of insecticides

Apparent Superluminal Behavior

The apparent superluminal propagation of electromagnetic signals seen in recent experiments is shown to be the result of simple and robust properties of relativistic field equations. Although the wave front of a signal passing through a classically forbidden region can never move faster than light, an attenuated replica of the signal is reproduced ``instantaneously'' on the other side of the barrier. The reconstructed signal, causally connected to the forerunner rather than the bulk of the input signal, appears to move through the barrier faster than light.Comment: 8 pages, no figure

(3+2) Neutrino Scheme From A Singular Double See-Saw Mechanism

We obtain a 3+2 neutrino spectrum within a left-right symmetric framework by invoking a singular double see-saw mechanism. Higgs doublets are employed to break $SU_{R}(2)$ and three additional fermions, singlets under the left-right symmetric gauge group, are included. The introduction of a singularity into the singlet fermion Majorana mass matrix results in a light neutrino sector of three neutrinos containing predominantly $\nu_{\alpha L}$, $\alpha=e,\mu,\tau$, separated from two neutrinos containing a small $\nu_{\alpha L}$ component. The resulting active-sterile mixing in the $5\times 5$ mixing matrix is specified once the mass eigenvalues and the $3\times3$ submatrix corresponding to the MNS mixing matrix are known.Comment: 5 pages, matches published versio

Pain control in healthcare organizations: Developing effective disease management programs

Although medicine possesses the knowledge and technology for preventing or relieving most pain, poor pain control is still widespread. Unrelieved pain causes unnecessary suffering and increases health care expenditures. Among the barriers to improving pain control are poor provider education in pain management, misguided beliefs about the inevitability of pain and the dangers of pain medication, provider resistance to changing practice patterns, and administrative resistance to implementing improvements that incur short-term costs but lead to long-term savings. In short, poor pain relief in America\u27s health care institutions is a system issue, and improvement requires a system-wide change. An effective program for improving pain management requires a multidisciplinary team committed to the task, ideally a triad consisting of a physician, a nurse, and a pharmacist. The triad needs administrative support in order to undertake needs assessment, offer provider and patient education, and perform continuous cycles of assessment, intervention, and reassessment of pain management. A strong information management base and an analytic engine are essential so that the team can evaluate outcomes from multiple perspectives (provider, payer, patient). The triad should identify a service area with clear pain problems, demonstrate improvements in this area, and then systematically move to other service areas. Educating providers and patients about pain and its control is essential for bringing about change. Improved pain management is a win-win situation for patients and institutions alike. Patients and families benefit from reduced suffering and improved quality of life, while institutions can offer more cost-effective care to patients

Evolutionary trajectories in rugged fitness landscapes

We consider the evolutionary trajectories traced out by an infinite population undergoing mutation-selection dynamics in static, uncorrelated random fitness landscapes. Starting from the population that consists of a single genotype, the most populated genotype \textit{jumps} from a local fitness maximum to another and eventually reaches the global maximum. We use a strong selection limit, which reduces the dynamics beyond the first time step to the competition between independent mutant subpopulations, to study the dynamics of this model and of a simpler one-dimensional model which ignores the geometry of the sequence space. We find that the fit genotypes that appear along a trajectory are a subset of suitably defined fitness \textit{records}, and exploit several results from the record theory for non-identically distributed random variables. The genotypes that contribute to the trajectory are those records that are not \textit{bypassed} by superior records arising further away from the initial population. Several conjectures concerning the statistics of bypassing are extracted from numerical simulations. In particular, for the one-dimensional model, we propose a simple relation between the bypassing probability and the dynamic exponent which describes the scaling of the typical evolution time with genome size. The latter can be determined exactly in terms of the extremal properties of the fitness distribution.Comment: Figures in color; minor revisions in tex

QM/MM Study of L-Lactate Oxidation by Flavocytochrome b2

In this work, we have performed molecular dynamics simulations using a hybrid Quantum Mechanics/Molecular Mechanics (QM/MM) scheme to study the mechanism of L-lactate oxidation by flavocytochrome b2 (Fcb2). Our results obtained at the QM(AM1)/MM level have been improved by single-point corrections using density functional theory (DFT) methods. Free energy surfaces have been calculated in the framework of the hydride transfer hypothesis. This mechanism involves the transfer of the lactate hydroxyl proton to H373 while the substrate αH atom is transferred as a hydride to the flavin mononucleotide (FMN) prosthetic group anchored in the active site. Four different systems have been modeled: wild-type enzyme considering R289 in a distal or a proximal conformation observed in crystal structures and the D282N and Y254L variants (with R289 in a distal position). Simulation results highlight the influence of the environment on the catalytic mechanism by describing a step-wise process in the WT enzyme with R289 in a distal position and a concerted mechanism for the other systems. In the step-wise mechanism, the hydride transfer to flavin can occur only after a proton transfer from substrate to H373. Modifications of the electrostatic field around L-lactate or H373 disfavor the highly charged complex resulting from this proton transfer. Simulations of the Y254L variant also reveal some effect of steric changes

Evolutionary branching in a stochastic population model with discrete mutational steps

Evolutionary branching is analysed in a stochastic, individual-based population model under mutation and selection. In such models, the common assumption is that individual reproduction and life career are characterised by values of a trait, and also by population sizes, and that mutations lead to small changes in trait value. Then, traditionally, the evolutionary dynamics is studied in the limit of vanishing mutational step sizes. In the present approach, small but non-negligible mutational steps are considered. By means of theoretical analysis in the limit of infinitely large populations, as well as computer simulations, we demonstrate how discrete mutational steps affect the patterns of evolutionary branching. We also argue that the average time to the first branching depends in a sensitive way on both mutational step size and population size.Comment: 12 pages, 8 figures. Revised versio