Interleukin-6 and interleukin-6 receptor secretion by chronic lymphatic leukaemia and normal B lymphocytes: effect of PMA and PWM

Interleukin-6 (IL-6) and soluble interleukin-6 receptor (sIL-6R) were detected in supernatants of cultures of B chronic lymphatic leukaemia (CLL) lymphocytes. Phorbol-12-myristate 13 acetate (PMA) caused a decrease in the levels of IL-6 in 14 out of 16 cultures and an increase in levels of sIL6R in all 15 cases. The effect of pokeweed mitogen (PWM) was variable and not significant. The levels of IL-6 were below the detection limit (60 pg/ml) in sera of 13 CLL patients whereas sIL-6R was detected (13 ng/ml to 97 ng/ml) in the 13 sera. IL6 was not detected in cultures of unstimulated or stimulated with PMA or PWM normal human B cells. Levels of sIL-6R were minimal in cultures of normal B lymphocytes and were increased in PMA stimulated cultures. The results are consistent with the view that B-CLL cells produce spontaneously IL-6 which could act in an autocrine fashion to cause shedding of surface IL-6R and account for the correlation found between serum levels of sIL-6R and B-CLL lymphocyte numbers. The fall in levels of IL-6 in PMA stimulated CLL cultures might express masking or degradation of IL-6 after combination with the receptor

Microwave Spectra and ab Initio Studies of Ar-Propane and Ne-Propane Complexes: Structure and Dynamics

Microwave spectra in the 7-26 MHz region have been measured for the van der Waals complexes, Ar-C H3 C H2 C H3, Ar- C13 H3 C H2 C H3, Ne20 -C H3 C H2 C H3, and Ne22 -C H3 C H2 C H3. Both a - and c -type transitions are observed for the Ar-propane complex. The c -type transitions are much stronger indicating that the small dipole moment of the propane (0.0848 D) is aligned perpendicular to the van der Waals bond axis. While the 42 transition lines observed for the primary argon complex are well fitted to a semirigid rotor Hamiltonian, the neon complexes exhibit splittings in the rotational transitions which we attribute to an internal rotation of the propane around its a inertial axis. Only c -type transitions are observed for both neon complexes, and these are found to occur between the tunneling states, indicating that internal motion involves an inversion of the dipole moment of the propane. The difference in energy between the two tunneling states within the ground vibrational state is 48.52 MHz for Ne20 -C H3 C H2 C H3 and 42.09 MHz for Ne22 -C H3 C H2 C H3. The Kraitchman substitution coordinates of the complexes show that the rare gas is oriented above the plane of the propane carbons, but shifted away from the methylene carbon, more so in Ne propane than in Ar propane. The distance between the rare gas atom and the center of mass of the propane, Rcm, is 3.823 Ã… for Ar-propane and 3.696 Ã… for Ne-propane. Ab initio calculations are done to map out segments of the intermolecular potential. The global minimum has the rare gas almost directly above the center of mass of the propane, and there are three local minima with the rare gas in the plane of the carbon atoms. Barriers between the minima are also calculated and support the experimental results which suggest that the tunneling path involves a rotation of the propane subunit. The path with the lowest effective barrier is through a C2v symmetric configuration in which the methyl groups are oriented toward the rare gas. Calculating the potential curve for this one-dimensional model and then calculating the energy levels for this potential roughly reproduces the spectral splittings in Ne-propane and explains the lack of splittings in Ar-propane

Transposable element evolution in Heliconius suggests genome diversity within Lepidoptera

Background Transposable elements (TEs) have the potential to impact genome structure, function and evolution in profound ways. In order to understand the contribution of transposable elements (TEs) to Heliconius melpomene, we queried the H. melpomene draft sequence to identify repetitive sequences. Results We determined that TEs comprise ~25% of the genome. The predominant class of TEs (~12% of the genome) was the non-long terminal repeat (non-LTR) retrotransposons, including a novel SINE family. However, this was only slightly higher than content derived from DNA transposons, which are diverse, with several families having mobilized in the recent past. Compared to the only other well-studied lepidopteran genome, Bombyx mori, H. melpomene exhibits a higher DNA transposon content and a distinct repertoire of retrotransposons. We also found that H. melpomene exhibits a high rate of TE turnover with few older elements accumulating in the genome. Conclusions Our analysis represents the first complete, de novo characterization of TE content in a butterfly genome and suggests that, while TEs are able to invade and multiply, TEs have an overall deleterious effect and/or that maintaining a small genome is advantageous. Our results also hint that analysis of additional lepidopteran genomes will reveal substantial TE diversity within the group

2s Hyperfine Structure in Hydrogen Atom and Helium-3 Ion

The usefulness of study of hyperfine splitting in the hydrogen atom is limited on a level of 10 ppm by our knowledge of the proton structure. One way to go beyond 10 ppm is to study a specific difference of the hyperfine structure intervals 8 Delta nu_2 - Delta nu_1. Nuclear effects for are not important this difference and it is of use to study higher-order QED corrections.Comment: 10 pages, presented at Hydrogen Atom II meeting (2000

On a diffuse interface model for tumour growth with non-local interactions and degenerate mobilities

We study a non-local variant of a diffuse interface model proposed by Hawkins--Darrud et al. (2012) for tumour growth in the presence of a chemical species acting as nutrient. The system consists of a Cahn--Hilliard equation coupled to a reaction-diffusion equation. For non-degenerate mobilities and smooth potentials, we derive well-posedness results, which are the non-local analogue of those obtained in Frigeri et al. (European J. Appl. Math. 2015). Furthermore, we establish existence of weak solutions for the case of degenerate mobilities and singular potentials, which serves to confine the order parameter to its physically relevant interval. Due to the non-local nature of the equations, under additional assumptions continuous dependence on initial data can also be shown.Comment: 28 page

On the principal bifurcation branch of a third order nonlinear long-wave equation

We study the principal bifurcation curve of a third order equation which describes the nonlinear evolution of several systems with a long--wavelength instability. We show that the main bifurcation branch can be derived from a variational principle. This allows to obtain a close estimate of the complete branch. In particular, when the bifurcation is subcritical, the large amplitude stable branch can be found in a simple manner.Comment: 11 pages, 3 figure

Measuring energy dependent polarization in soft gamma-rays using Compton scattering in PoGOLite

Linear polarization in X- and gamma-rays is an important diagnostic of many astrophysical sources, foremost giving information about their geometry, magnetic fields, and radiation mechanisms. However, very few X-ray polarization measurements have been made, and then only mono-energetic detections, whilst several objects are assumed to have energy dependent polarization signatures. In this paper we investigate whether detection of energy dependent polarization from cosmic sources is possible using the Compton technique, in particular with the proposed PoGOLite balloon-experiment, in the 25-100 keV range. We use Geant4 simulations of a PoGOLite model and input photon spectra based on Cygnus X-1 and accreting magnetic pulsars (100 mCrab). Effective observing times of 6 and 35 hours were simulated, corresponding to a standard and a long duration flight respectively. Both smooth and sharp energy variations of the polarization are investigated and compared to constant polarization signals using chi-square statistics. We can reject constant polarization, with energy, for the Cygnus X-1 spectrum (in the hard state), if the reflected component is assumed to be completely polarized, whereas the distinction cannot be made for weaker polarization. For the accreting pulsar, constant polarization can be rejected in the case of polarization in a narrow energy band with at least 50% polarization, and similarly for a negative step distribution from 30% to 0% polarization.Comment: 11 pages, 12 figures; updated to match version accepted for publication in Astroparticle Physics (only minor changes

Adolescent Health: Think, Act, Grow (TAG)—A Strengths-Based Approach to Promoting Health in Youth

Adolescent Health: Think, Act, Grow® (TAG) is a national call to action to promote adolescent health and healthy development. Led by the Department of Health and Human Services Office of Adolescent Health and developed with the input of national organizations, it builds on the collective wisdom of youth-serving professionals and seeks to raise the profile of adolescent health in the national discourse. Using TAG, the Office of Adolescent Health conducts outreach and delivers tools and information that support the integration of positive youth development precepts into the ongoing work of federal, state, and local public agencies; youth-serving health, public health, education, and social service professionals and organizations; faith- and community-based organizations; workforce development organizations and employers; and other stakeholders. TAG does not provide a formulaic blueprint for action, but instead encourages youth-serving organizations to use approaches that are consistent with their mission, objectives, priorities, and tactics. Preliminary evaluation findings indicate interest in the overall concept and resources of TAG, with partners citing the sharing of resources as a primary engagement strategy

Diffuse-interface model for rapid phase transformations in nonequilibrium systems

A thermodynamic approach to rapid phase transformations within a diffuse interface in a binary system is developed. Assuming an extended set of independent thermodynamic variables formed by the union of the classic set of slow variables and the space of fast variables, we introduce finiteness of the heat and solute diffusive propagation at the finite speed of the interface advancing. To describe the transformation within the diffuse interface, we use the phase-field model which allows us to follow the steep but smooth change of phases within the width of diffuse interface. The governing equations of the phase-field model are derived for the hyperbolic model, model with memory, and for a model of nonlinear evolution of transformation within the diffuse-interface. The consistency of the model is proved by the condition of positive entropy production and by the outcomes of the fluctuation-dissipation theorem. A comparison with the existing sharp-interface and diffuse-interface versions of the model is given.Comment: 15 pages, regular article submitted to Physical Review