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The citrus leafminer (CLM), Phyllocnistis citrella Stainton causes injury to citrus and related species in the Rutaceae family. The damage that the CLM larvae can cause is significant in citrus plantations. We tested two citrus cultivars — ‘Kinnow’ (Citrus reticulata Blanco) and ‘Fairchild’ (a hybrid of Citrus reticulata Clementine x Orlando Tangelo) — to quantify CLM larvae infestation and effect on the physiology of the citrus cultivars. We then compared the CLM larval weight with its associated damage. To calculate infestation level, mine area and total leaf area, we used the image analysis technique. The infestation level of CLM was higher in ‘Fairchild’ than in ‘Kinnow’ cultivar of citrus. For both cultivars, larval weight of CLM was directly proportional to the amount of mines generated. Taken together, the results of this study suggest that the mines that CLM larvae generate pose significant effect on the net photosynthetic rates and water use efficiency of citrus nursery plants. These results will help improve our understanding of the interaction between CLM and citrus nursery plants and effect of the pest on the yield potential of the crop.
Pakistan is at the verge of polio eradication but isolation of non-polio enteroviruses (NPEVs) from acute flaccid paralysis (AFP) cases may result in serious or even fatal outcome. Many enteroviruses share similar symptoms and epidemiology as is the case with poliovirus and coxsackievirus (CV). The present study was designed to genetically characterize coxsackievirus B (CV-B) serotypes isolated from non-polio acute flaccid paralytic children, as well as to understand their probable role in paralysis. A total of 63 (20·1%) out of 313 stool samples during 2013 were found positive for NPEVs in rhabdomyosarcoma cells. Only 24 (38·0%) NPEVs were typed as CV-B by microneutralization assay and were further characterized by sequencing of the viral protein 1 (VP1) gene. Molecular phylogenetic analyses classified the study strains into six coxsackievirus B serotypes (coxsackievirus B1 to B6) with their respective prototype strains with evidence of epidemiological linkage and distinct clusters. Moreover, four major differences were found within the amino acid sequences of BC-loop in VP1 of CV-B strains. In conclusion, this study presented the molecular evolutionary genetic overview and distinct phylogenetic pattern of CV-B isolates from AFP cases in Pakistan, and explored the possible link between CV-B infections and AFP cases. Furthermore, our data reveal that these viruses might contribute to the incidence of paralysis in population and there is need of time to establish an enterovirus surveillance system for better understanding of epidemiological and virological characteristics of NPEV infections associated with AFP cases in the country.
We consider the ergodic (or additive eigenvalue) problem for the Neumann-type boundary-value problem for Hamilton–Jacobi equations and the corresponding discounted problems. Denoting by uλ the solution of the discounted problem with discount factor λ > 0, we establish the convergence of the whole family to a solution of the ergodic problem as λ → 0, and give a representation formula for the limit function via the Mather measures and Peierls function. As an interesting by-product, we introduce Mather measures associated with Hamilton–Jacobi equations with the Neumann-type boundary conditions. These results are variants of the main results in a recent paper by Davini et al., who study the same convergence problem on smooth compact manifolds without boundary.
Two-fluid quantum magnetohydrodynamic (QMHD) equations are employed to investigate linear and nonlinear properties of the magnetosonic waves in a semi-relativistic dense plasma accounting for degenerate relativistic electrons. In the linear analysis, a plane wave solution is used to derive the dispersion relation of magnetosonic waves, which is significantly modified due to relativistic degenerate electrons. However, for a nonlinear investigation of solitary and shock waves, we employ the reductive perturbation technique for the derivation of Korteweg–de Vries (KdV) and Korteweg–de Vries Burger (KdVB) equations, admitting nonlinear wave solutions. Numerically, it is shown that the wave frequency decreases to attain a lowest possible value at a certain critical number density
, and then increases beyond
as the plasma number density increases. Moreover, the relativistic electrons and associated pressure degeneracy lead to a reduction in the spatial extents of the magnetosonic waves and a strengthening of the shock amplitude. The results might be important for understanding the linear and nonlinear magnetosonic excitations in dense astrophysical plasmas, such as in white dwarfs, magnetars and neutron stars, etc., where relativistic degenerate electrons are present.
The formation and propagation characteristics of small-amplitude magnetoacoustic dark/grey solitons are investigated in a semi relativistic degenerate magnetoplasma whose constituents are electrons and singly ionized positive ions. For this purpose, the electrons are assumed to follow the degeneracy pressure law through the Chandrasekhar equation of state, while the inertial cold ions are taken as non-degenerate and magnetized. By solving the one-fluid quantum magnetohydrodynamic (QMHD) model with the aid of a reductive perturbation technique, a nonlinear Schrödinger (NLS) equation is derived for weakly nonlinear envelope magnetoacoustic solitons. The NLS equation admits the existence of stable excitations, e.g. dark and grey solitons for which the condition
holds. Numerical results reveal that the variation of plasma number density, magnetic field strength, relativistic parameter
and the quantum parameter
significantly modify the profiles of the envelope magnetoacoustic solitons. The present results are important to understanding of the nonlinear dynamics of magnetoacoustic solitons in astrophysical dense magnetoplasmas (viz., white dwarfs, magnetars, neutron stars, etc.), where the relativistic degeneracy effects play a vital role in collective interactions.
We assessed for vancomycin-resistant Staphylococcus aureus (VRSA) precursor organisms in southeastern Michigan, an area known to have VRSA. The prevalence was 2.5% (pSK41-positive methicillin-resistant S. aureus, 2009–2011) and 1.5% (Inc18-positive vancomycin-resistant Enterococcus, 2006–2013); Inc18 prevalence significantly decreased after 2009 (3.7% to 0.82%). Risk factors for pSK41 included intravenous vancomycin exposure.
Infect Control Hosp Epidemiol 2014;35(12):1531–1534
We have investigated some linear as well as nonlinear properties of ion-acoustic wave (IAW) propagation in a non-uniform two-electron-temperature magnetoplasma in the presence of ion-sheared flows. In the linear limit, new dispersion relation has been derived and analyzed in some interesting limiting cases. It is shown that ion-sheared flow can drive the IAW unstable under a certain limit.Whereas, in the nonlinear case, dipolar and vortex street type solutions can appear. It is observed that by choosing some typical parameters of Earth's auroral region, the scalelength of the nonlinear structures are significantly modified. The present investigation might be very useful to explain various types of nonlinear structure formation which has been observed in space environments where two-electron-temperature plasma exist.
This study aimed to describe the transmission dynamics, the serological and virus excretion patterns of Nipah virus (NiV) in Pteropus vampyrus bats. Bats in captivity were sampled every 7–21 days over a 1-year period. The data revealed five NiV serological patterns categorized as high and low positives, waning, decreasing and increasing, and negative in these individuals. The findings strongly suggest that NiV circulates in wild bat populations and that antibody could be maintained for long periods. The study also found that pup and juvenile bats from seropositive dams tested seropositive, indicating that maternal antibodies against NiV are transmitted passively, and in this study population may last up to 14 months. NiV was isolated from the urine of one bat, and within a few weeks, two other seronegative bats seroconverted. Based on the temporal cluster of seroconversion, we strongly believe that the NiV isolated was recrudesced and then transmitted horizontally between bats during the study period.
A polymeric chelating ligand containing hydroxamic acid and amidoxime functional groups were prepared from acrylate polymer grafted acacia cellulose and this ligand was introduced to remove heavy metals from industrial wastewaters. The heavy metals binding property with this ligand is excellent up to 3.78 mmol/ g sorbent and the rate of exchange of some metals was very fast i.e. t½ ≈ 6 min (average). Two types of wastewater from electroplating plants used in this study those containing chromium, zinc, nickel, copper and iron etc. Before removing heavy metals from wastewater, pH was adjusted to 4 and various metal concentrations were used for finding the extraction capability of the ligand. It was found that the metals recovery was highly efficient, up to 99.99% of several heavy metals were removed from electroplating wastewater using the ligands. Therefore, the proposed polymeric chelating ligands could be used to the remove such heavy metals from industrial wastewater and as well as effective ligands for environment protection.
This paper provides an estimation of the point prevalence of fascioliasis and its economic impact in terms of increased milk yield after chemotherapy of a bovine population from the district of Toba Tek Singh, Punjab, Pakistan. A total of 2400 cattle and buffaloes were examined quantitatively using the McMaster egg-counting technique. Infected cattle and buffaloes (50 of each) were randomly selected and each divided into two groups of 25 animals. Groups A (buffaloes) and C (cattle) were treated with oxyclozanide (orally, 16.6 mg kg− 1 body weight). Groups B and D served as negative controls for buffaloes and cattle, respectively. Pre- and post-treatment milk yield was recorded to determine if there were any changes in milk yield after treatment. Of 2400 faecal samples analysed, 654 (27.25%) were positive for Fasciola spp. with a mean number of eggs per gram (EPG) of 503.2. The point prevalence and worm burden of fascioliasis was significantly higher (OR = 2.13; P < 0.05) in buffaloes (34.58%; 415/1200; mean EPG maximum likelihood = 521.4) as compared to that of cattle (19.92%; 239/1200; mean EPG maximum likelihood = 415.8). Among the parasite species, F. gigantica (19.88%; 477/2400) was predominant (OR = 3.12; P < 0.05) as compared to F. hepatica (7.38%; 177/2400). An average daily increase of 0.67 and 0.87 litres of milk, with 0.41% and 0.37% more fat per animal, was observed in oxyclozanide-treated buffaloes and cattle, respectively. The economic value of reduced production of infected animals was estimated as US$0.33 and 0.32 per animal per day for cattle and buffaloes, respectively.
Dispersion relation for the low-frequency magnetic electron-drift vortex (MEDV) mode in an inhomogeneous dense quantum plasma has been derived. New class of purely growing instabilities are found to exist on a time scale of the order of ion plasma period. We found that the MEDV mode become unstable when the propagation direction is perpendicular to the equilibrium density gradients. We believe that the present investigation would be useful to understand the wave phenomena and in the study of magnetic field generation in laser-produced plasmas as well as in dense space plasmas, where quantum effects are expected to play a dominant role.
Nonlinear equations which govern the dynamics of low-frequency (ω ⪡ ωci, where ω is the perturbation frequency of the wave and ωci is the ion gyro-frequency), ion-temperature-gradient-driven modes in the presence of equilibrium density, temperature and magnetic field gradients are derived. New set of nonlinear equations are derived. In the nonlinear case, new types of solutions in the form of dipolar vortices and vortex streets are found to exist in dense quantum plasma. These structures are found to be formed on very short spatial scales.
The coupled Shukla–Varma (SV) and convective cell mode is revisited in classical and quantum dusty magnetoplasmas. It is shown that the inclusion of electron thermal effects modifies the original coupled SV and convective cell mode. It is also discussed how the quantum effects can be incorporated in the coupled SV and convective cell mode.
The implosion dynamics and fusion parameters of a high density D-T fibre plasma driven by Z-pinch with current stepping technique is investigated. Our numerical results demonstrate that a current-stepping technique reduces the minimum pinch radius, and as a result high density, high temperature plasma can be formed. Thus a staged pinch device with current-stepping technique can be used as an alternative approach to achieve fusion conditions with relatively small values of discharge current and with a long pulse duration.
The imploding plasma column of a gas-puff Ζ-pinch has been used to compress the target-gas-embedded axial magnetic field in the presence of plasma pressure. The dynamics of a two-gas gas-puff Ζ-θ pinch is studied with different forms of applied current profiles. We find that the inclusion of a kinetic pressure term introduces the usual β–term, which delays and reduces the maximum compression. On the other hand, for fixed β, compression at an earlier time can be achieved for a large density ratio of the test to the driver gas at the interface position. For the pressure-free case, our earlier results are completely recovered.
We investigate the effect of a weak ambipolar field on non-local heat transport by solving the reduced Fokker-Planck equation in the non-diffusive approximation for the electron distribution function. It turns out that for a moderately high-Z plasma with steep gradients the maximum-heat-flow expression is modified and the ensuing results compare favourably with the experimental values. However, in the gentle-gradient limit the classical Spitzer-Härm heat flux expression is unaltered.
We investigate the implosion of a dense τ-pinch plasma driven by an annular finite-thickness gas-puff Z-pinch. The imploding Z-pinch traps an axial magnetic field Bz, compressing it to large values in an extremely short time. The temporal variation of Bz then induces an azimuthal τ current on the surface of a fibre placed on the axis, with a rise time an order of magnitude shorter than the rise time of the Z-pinch current. Our numerical results demonstrate that, for a thick gas-puff layer, maximum compression occurs before the current peaks.We also find that at peak compression, fuel densities of the order of 1025 cm-3 and temperatures above 10 keV can be achieved on a time scale of the order of 0.1 ns. Thus a Lawson parameter nτ ≈ 1014 s cm-3 for a DT fibre becomes achievable. The snowplough effect in the Z-pinch exercises a stabilization effect on the growth of sausage and Rayleigh—Taylor instabilities. In the limit of a very thin gas-puff layer, previous results are fully recovered.
Nuclear factor (NF)-κB is perhaps the most intensely studied eukaryotic transcription factor, mainly because of its pivotal role in controlling varied biological effects ranging from inflammatory-,immune-, and stress-induced responses to cell fate decisions such as proliferation, differentiation, tumorigenesis, and apoptosis. The mammalian NF-κB family consists of five members: RelA (p65), RelB, c-Rel, NF-κB1 (p50 and its precursor p105), and NF-κB2 (p52 and its precursor p100). These proteins share a conserved N-terminal 300-amino acid Rel homology domain (RHD) that contains a nuclear localization signal (NLS) and is responsible for dimerization, sequence-specific DNA binding, and interaction with inhibitory IκB proteins (Figure 86.1A). A critical feature of RelA, RelB, and c-Rel that distinguishes them from p50 and p52 is the presence of a transactivation domain (TAD) within the carboxy-terminal region of these proteins (Figure 86.1A).
The diverse biological effects of NF-κB are mediated, in part, by the ability of NF-κB proteins to form numerous homo- and heterodimers that differentially regulate target genes (1). For example, p50 and p52 homodimers serve as repressors, whereas dimers containing RelA or c-Rel are transcriptional activators. Heterodimers of RelB with either p50 or p52 display a greater regulatory flexibility, and function both as an activator and a repressor (1,2). Accumulating evidence suggests that activation of specific dimers is mediated by distinct upstream signaling pathways, which in turn are activated in a stimulus- and cell-specific manner (2,3). This chapter begins with an overview of the current state of knowledge about NF-κB, and then discusses the role for this fascinating transcription factor in the endothelium.
The dynamics of low-frequency, short-wavelength electrostatic (SWES) drift waves in a self-gravitating, non-uniform, collisional dusty magnetoplasma with equilibrium dust-velocity gradients is studied in the present work. By employing the dust continuity and momentum equations to describe the dust dynamics and Boltzmann distribution for the electrons and ions, we have derived a new set of nonlinear mode coupling equations. In the linear limit, it is found that SWES drift waves are subjected to dissipative instability in the presence of an equilibrium dust sheared flow and self-gravitation effect. On the other hand, in the nonlinear case, it is shown that possible stationary solutions of the nonlinear equations are dipolar vortices.
The terms ‘conversion’, ‘hysteria’ and ‘conversion hysteria’ were used interchangeably to describe a condition characterised by a single somatised symptom, often pseudo-neurological in nature. DSM–III (American Psychiatric Association, 1980) expanded the concept of conversion to generalised symptoms involving loss or alteration of physical functioning suggestive of a physical disorder, along with a clinical indication that the conversion was an expression of psychological conflict or need. The type of symptom or deficit should be specified as: with motor symptom or deficit, with sensory symptom or deficit, with seizure or convulsions, or with mixed presentation (Kaplan & Sadock, 2004).