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We analyze a 137 ks exposure X-ray spectrum of the Seyfert 1 galaxy NGC 5548 obtained with the XMM-NewtonReflection Grating Spectrometer. Due to the long exposure time, the spectrum is of higher statistical quality than the previous observations of this AGN. Therefore, we detect for the first time in NGC 5548 inner-shell transitions from $\ion{O}{iii}$to $\ion{O}{vi}$ions, and the Unresolved Transition Array of M-shell iron. The warm absorber found from this X-ray observation spans three orders of magnitude in ionization parameter. We detect $\ion{O}{iii}$, which is as lowly ionized as the warm absorber detected in the UV band, to $\ion{Fe}{xxiv}$. For $\ion{O}{vi}$the column density determined from our X-ray data is an order of magnitude larger than the column density measured in previous UV observations. We conclude that there is substantially more low ionized material than previously deduced from UV observations. However, only a few percent of the warm absorber detected in the X-rays is lowly ionized. A 99.9% significant increase in the derived absorbing column density with higher ionization states is observed. The outflow velocities determined from the X-ray absorption lines are consistent with those deduced from the UV lines, evidence, together with the detection of $\ion{O}{vi}$, that the X-ray and UV warm absorber are different manifestations of the same phenomenon. From a simple mass conservation argument, we indicate that our data set is consistent with an outflow with small opening angle formed due to instabilities in the accretion disk. Possible due to uncertainties in the radiative transport mechanism, an apparent deviant iron to oxygen abundance is detected. No strong relativistically broadened emission lines of $\ion{O}{viii}$, $\ion{N}{vii}$and $\ion{C}{vi}$were detected.

Mid-infrared images of the Seyfert 1 galaxy Mrk 279obtained with the ISO satellite are presented together with the results of a one-year monitoring campaign of the 2.5-11.7 μm spectrum. Contemporaneous optical photometric and spectrophotometric observations are also presented. The galaxy appears as a point-like source at the resolution of the ISOCAM instrument (4-5″). The 2.5-11.7 μm average spectrum of the nucleus in Mrk 279shows a strong power law continuum with $\alpha = -0.80\pm0.05$(${ F_{\nu} \propto \nu^{\alpha}}$) and weak PAH emission features. The Mrk 279spectral energy distribution shows a mid-IR bump, which extends from 2 to 15-20 μm. The mid-IR bump is consistent with thermal emission from dust grains at a distance of $\ga 100$lt-d. No significant variations of the mid-IR flux have been detected during our observing campaign, consistent with the relatively low amplitude (~10% rms) of the optical variability during the campaign. The time delay for Hβline emission in response to the optical continuum variations is $\tau = 16.7^{+5.3}_{-5.6}$days, consistent with previous measurements.

Data from the first three years of RXTEobservations have been systematically analyzed to yield a set of 300 day 2-10 keV light curves with similarly uniform, ~5 day sampling, for a total of nine Seyfert 1 galaxies. This is the first X-ray variability survey to probe consistently timescales longer than a few days in a large number of active galactic nuclei (AGNs). Comparison to ASCAdata covering a similar band but much shorter (1 day) timescales shows that all the AGNs are more strongly variable on long timescales than on short timescales. This increase is greatest for the highest luminosity sources. The well-known anticorrelation between source luminosity and variability amplitude is both stronger and shallower in power-law slope when measured on long timescales. This is consistent with a picture in which the X-ray variability of Seyfert 1 galaxies can be can be described by a single, universal fluctuation power-density shape for which the cutoff moves to longer timescales for higher luminosity sources. All of the Seyfert 1 galaxies exhibit stronger variability in the relatively soft 2-4 keV band than in the harder 7-10 keV band. This effect is much too pronounced to be explained by simple models based either on the dilution of the power-law continuum by the Compton reflection component or on the hard X-rays being produced in a static, pair-dominated, plane-parallel Comptonizing corona.

The patterns of cell proliferation and cell migration were studied in three patients with the Sezary syndrome using autoradiographic techniques. Cell labeling patterns following pulse labeling with tritiated thymidine in vivo indicated that Sezary cells proliferate actively in skin and in lymph nodes but that few if any Sezary cells proliferate in the peripheral blood. In two of the patients serial samples were obtained. Label dilution patterns in skin and blood over time suggested that circulating Sezary cells originated in extracutaneous sites where cells were proliferating more rapidly than in the skin. Cells labeled in extracutaneous sites of proliferation appear rapidly in the blood, and their transit time through the peripheral blood compartment is short. Circulating Sezary cells may then be deposited in the skin where they resume proliferation at a low rate. Thus, while Sezary cells proliferate in both cutaneous and extracutaneous sites, proliferation appears to be more rapid in extracutaneous sites such as lymph nodes. This suggests that trials of systemic therapeutic approaches should be undertaken.

The cutaneous infiltrate in mycosis fungoides (MF) is predominantly composed of T4-positive T-cells. Attempts to distinguish the early stages of this condition from benign inflammatory infiltrates using anti-T3, T4 and other T-cell-associated antibodies have hitherto been unsucessful. Recently a monoclonal antibody BE 2 has been described as selectively reacting against leukemic cells in patients with cutaneous T-cell lymphoma. To investigate whether the BE 2 antigen is differentially expressed in different stages of MF and benign dermatoses, thus facilitating diagnosis, especially of early MF, the reactivity of monoclonal antibody BE 2 against cutaneous infiltrates from such conditions was assessed.

Two-fold specificity in drug delivery obtained through the localized activation of drugs by physical means and the attachment of drugs to proteins that bind to target cells might be used for highly selective cancer chemotherapy or for immunosuppression. Toward this end, a monoclonal antibody against an antigen on the surface of T lymphocytes was covalently attached to liposomes containing a phototoxic drug, pyrene, bound to the lipid bilayer. When unfractionated peripheral blood lymphocytes, or B- and T-cell lines, were irradiated after treatment with these liposomes, T cells were killed while B cells were spared, demonstrating the validity of the approach in a simple in vitro assay.

Reactivity of a monoclonal antibody with human Langerhans cells was demonstrated by a double-labeling immunofluorescence technique. Ia-bearing cells of the epidermis (Langerhans cells) were reactive with this antibody both in frozen sections and in cell suspensions prepared from human epidermis. This monoclonal antibody was unreactive with non-Ia-bearing epidermal cells and with peripheral blood B cells, T cells, and monocytes but did not bind to 70% of intrathymic lymphocytes. These observations further distinguish Langerhans cells from classical monocytes. Furthermore, this monoclonal antibody is a highly specific marker for the in vivo identification and in vitro isolation of Langerhans cells.

We have undertaken near-continuous monitoring of the Seyfert 1 galaxy NGC 7469 in the X-ray with RXTEover a ~30 day baseline. The source shows strong variability with a root mean square (rms) amplitude of ~16% and peak-to-peak variations of a factor of order 2. Simultaneous data over this period were obtained in the ultraviolet (UV) using IUE, making this the most intensive X-ray UV/X-ray variability campaign performed for any active galaxy. Comparison of the continuum light curves reveals very similar amplitudes of variability but different variability characteristics, with the X-rays showing much more rapid variations. The data are not strongly correlated at zero lag. The largest absolute value of the correlation coefficient occurs for an anticorrelation between the two bands, with the X-ray variations leading the UV by ~4 days. The largest positive correlation is for the ultraviolet to lead the X-rays by ~4 days. Neither option appears to be compatible with any simple interband transfer function. The peak positive correlation at ~4 days occurs because the more prominent peaks in the UV light curve appear to lead those in the X-rays by this amount. However, the minima of the light curves are near simultaneous. These observations provide new constraints on theoretical models of the central regions of active galactic nuclei. Models in which the observed UV emission is produced solely by reradiation of absorber X-rays are ruled out by our data, as are those in which the X-rays are produced solely by Compton upscattering of the observed UV component by a constant distribution of particles. New or more complex models must be sought to explain the data. We require at least two variability mechanisms, which have no simple relationship. We briefly explore means by which these observations could be reconciled with theoretical models.

The present study investigated the effect of vibrotactile stimulation on relaxation as measured by EMG recording. Forty-eight subjects from three age groups were randomly divided into 8 experimental groups:(1) simultaneous footrest vibration and back vibration(A1C1);(2) simultaneous footrest vibration and back roller(A1C2); (3) simultaneous footrest vibration, back vibration and back roller(A1C3); (4) footrest vibration alone(A1C4); (5) back vibration alone(A2C1); (6) back roller alone(A2C2); (7) simultaneous back vibration and back roller(A2C3); and(8) control group (no vibration/stimulation)(A2C4). The three major variables studied were footrest vibration(A1 andA2), pre- and post-EMG measures(B1 andB2), and back vibration(C1C2C3C4). Results showed that footrest vibration had a significant effect on relaxation. Other conditions (except the control) produced a decrease in EMG levels, but did not reach significance. Pre- and postmeasures by experimental conditions were also significantly different. Application of vibration as an aid in relaxation is discussed.

Bone-marrow-derived (B) and thymus-derived (T) lymphocytes can be distinguished by the presence of a number of receptors and differentiation antigens. The presence of these markers has facilitated the identification and characterization of the mononuclear cells in a number of animal and human lymphoid malignancies. We describe here the immunological properties of human leukemia cells that are highly unusual, since they simultaneously bear the receptor for sheep erythrocytes characteristic of human T lymphocytes and the receptor for antigen-antibody-complement complexes characteristic of human B lymphocytes. A small number (about 2%) of normal human lymphocytes bearing both of these receptors was also identified.

Most quasars and Seyfert 1 galaxies have spectra that rise from optical wavelengths into the 60–100 μm infrared region, beyond which they must suffer a sharp cutoff indicated by the lack of observed millimetre emission. There is evidence1–4that the infrared emission receives contributions from both thermal emission by interstellar dust and synchrotron radiation from a compact source. Determining the nature of the infrared emission is thus an important step in understanding the structure of quasars and Seyfert 1 galaxies. We report here observations at 438-μm wavelength of the Seyfert 1 galaxy NGC4151 using the UKT14 bolometer on the James Clerk Maxwell Telescope. We find a 5σ upper limit of 200 mJy in an 11″ aperture. Comparison with an earlier measurement at 155-μm indicates that at least half of the 155-μm flux is due to thermal dust emission. The remainder may be from a synchrotron source which becomes self-absorbed at wavelengths of less than 80 μm.