Medium modification of jet fragmentation in Au+Au collisions at √[s(NN)]=200 GeV measured in direct photon-hadron correlations.

The jet fragmentation function is measured with direct photon-hadron correlations in p+p and Au+Au collisions at √[s(NN)]=200 GeV. The p(T) of the photon is an excellent approximation to the initial p(T) of the jet and the ratio z(T)=p(T)(h)/p(T)(γ) is used as a proxy for the jet fragmentation function. A statistical subtraction is used to extract the direct photon-hadron yields in Au+Au collisions while a photon isolation cut is applied in p+p. I(AA), the ratio of hadron yield opposite the photon in Au+Au to that in p+p, indicates modification of the jet fragmentation function. Suppression, most likely due to energy loss in the medium, is seen at high z(T). The associated hadron yield at low z(T) is enhanced at large angles. Such a trend is expected from redistribution of the lost energy into increased production of low-momentum particles.

Measurement of direct photons in Au+Au collisions at √(s(NN))=200 GeV.

We report the measurement of direct photons at midrapidity in Au+Au collisions at √(s(NN))=200 GeV. The direct photon signal was extracted for the transverse momentum range of 4 GeV/c

Cold nuclear matter effects on J/ψ yields as a function of rapidity and nuclear geometry in d+A collisions at sqrt[s(NN)]=200 GeV.

We present measurements of J/ψ yields in d+Au collisions at sqrt[s(NN)]=200 GeV recorded by the PHENIX experiment and compare them with yields in p+p collisions at the same energy per nucleon-nucleon collision. The measurements cover a large kinematic range in J/ψ rapidity (-2.2

Enhanced production of direct photons in Au + Au collisions at square root(S(NN)) = 200 GeV and implications for the initial temperature.

The production of e+ e- pairs for m(e+ e-)<0.3 GeV/c2 and 1

Transition in yield and azimuthal shape modification in dihadron correlations in relativistic heavy ion collisions.

Hard-scattered parton probes produced in collisions of large nuclei indicate large partonic energy loss, possibly with collective produced-medium response to the lost energy. We present measurements of π^{0} trigger particles at transverse momenta p{T}{t}=4-12 GeV/c and associated charged hadrons (p{T}{a}=0.5-7 GeV/c) vs relative azimuthal angle Δϕ in Au+Au and p+p collisions at sqrt[s{NN}]=200 GeV. The Au+Au distribution at low p{T}{a}, whose shape has been interpreted as a medium effect, is modified for p{T}{t}<7 GeV/c. At higher p{T}{t}, the data are consistent with unmodified or very weakly modified shapes, even for the lowest measured p{T}{a}, which quantitatively challenges some medium response models. The associated yield of hadrons opposing the trigger particle in Au+Au relative to p+p (I{AA}) is suppressed at high p{T} (I{AA}≈0.35-0.5), but less than for inclusive suppression (R{AA}≈0.2).

Charged Kaon interferometric probes of space-time evolution in Au+Au collisions at sqrt[S(NN)]=200 GeV.

Bose-Einstein correlations of charged kaons are used to probe Au+Au collisions at sqrt[S(NN)]=200 GeV and are compared to charged pion probes, which have a larger hadronic scattering cross section. Three-dimensional Gaussian source radii are extracted, along with a one-dimensional kaon emission source function. The centrality dependences of the three Gaussian radii are well described by a single linear function of N(part)1/3 with a zero intercept. Imaging analysis shows a deviation from a Gaussian tail at r greater than or approximately equal to 10 fm, although the bulk emission at lower radius is well described by a Gaussian. The presence of a non-Gaussian tail in the kaon source reaffirms that the particle emission region in a heavy-ion collision is extended, and that similar measurements with pions are not solely due to the decay of long-lived resonances.

Oligonucleotide linked to human gammaglobulin specifically diminishes anti-DNA antibody formation in cultured lymphoid cells from patients with systemic lupus erythematosus.

In vitro studies were undertaken to determine whether the level of anti-DNA antibody can be modulated in humans with systemic lupus erythematosus (SLE). DNA fragments of different sizes, i.e., oligonucleotide (N20-30) or oligonucleotide (N10-100), were covalently linked either to human gammaglobulin (HGG) and used as tolerogens or to keyhole limpet hemocyanin and used as immunogens. Experiments were done to determine whether such tolerogens specifically diminish antibodies to denatured DNA, native DNA, or both. PBL were obtained from 87 patients with SLE, 55 of whom spontaneously produced anti-DNA antibodies in vitro. Furthermore, of these 55 test subjects 23 made anti-DNA antibodies in response to antigen challenge in vitro. Exposure of PBL to tolerogenic oligonucleotide-HGG reduced spontaneous antibody formation in 34 of the 55 patients' PBL and abrogated the in vitro-induced response in all instances. The suppression was tolerogen specific. In some SLE patients lymphoid cells were suppressed by both (N10-100)-HGG and (N20-30)-HGG, while in others lymphoid cells were suppressed by only one. Longitudinal studies of spontaneous antibody production showed that the same tolerogens consistently reduced anti-DNA antibody formation in lymphoid cells of 12 patients on several occasions over a 2-yr interval, but in 8 others the results were either variable or inconsistent. In contrast, tolerogens consistently abrogated the antigen-induced response in all 23 patients' PBL. These results obtained in humans in vitro suggest that the principle of carrier-determined tolerance could be applied as a specific therapy for SLE in vivo.

Elliptic flow for phi mesons and (anti)deuterons in Au+Au collisions at square root of sNN=200 GeV.

Differential elliptic flow (v(2)) for phi mesons and (anti)deuterons (d)d is measured for Au+Au collisions at square root of sNN=200 GeV. The v(2) for phi mesons follows the trend of lighter pi+/- and K+/- mesons, suggesting that ordinary hadrons interacting with standard hadronic cross sections are not the primary driver for elliptic flow development. The v(2) values for (d)d suggest that elliptic flow is additive for composite particles. This further validation of the universal scaling of v(2) per constituent quark for baryons and mesons suggests that partonic collectivity dominates the transverse expansion dynamics.

Immunologic tolerance to DNA in B cell lines from both normal and autoimmune mice.

We examine whether B cell lines enriched for DNA specificity from either autoimmune (BWF1) or normal mice (Balb/c) can be rendered unresponsive to autoantigen in terms of the specific suppression of direct antibody-forming cells to DNA. These B cell lines were both Lyt-1 positive and negative. Preincubation with oligonucleotide, covalently linked to mouse gamma-globulin, specifically suppressed the antigen-driven response elicited by DNA horse red blood cells in B cell lines from both strains of mice. There is a 5-fold difference in susceptibility to DNA-specific tolerance induction between B cell lines of BWF1 and Balb/c mice. Thus, B cells from autoimmune mice do not appear to have an inherent absolute defect in being rendered tolerant to autoantigen, but are relatively less susceptible to DNA-specific tolerance than nonautoimmune cell lines.

A novel technique to link either proteins or peptides to gammaglobulin to construct tolerogens.

In order to extend the concept of constructing tolerogens (i.e., compounds which induce immunologic tolerance), we developed a novel method to covalently link either protein or peptide to isologous gammaglobulin. We used disuccinimidyl suberate (DSS) for preparing protein conjugates in solution in a novel use of this reagent. We tested the efficacy of this method in two different experimental models: in the first, we found that administration of pigeon cytochrome C conjugated to mouse IgG in vivo induces T cell unresponsiveness in vitro. In the second, we induced unresponsiveness to factor VIII light chain both in newborn and, more importantly, in adult mice already immune to factor VIII. We hope that this simple method will provide a powerful tool to construct tolerogens useful in the specific treatment of either allergic or autoimmune diseases.

Detection of antibody-forming cells and humoral antibody to horseradish peroxidase.

Two new simple methods for detecting antibody-forming cells by hemolytic plaque assay and hemagglutinating antibody to horseradish peroxidase have been developed in mice. Both techniques utilize as target, sheep erythrocytes coupled directly with horseradish peroxidase. These assays are sensitive, antigen-specific and are useful to quantitate both direct and indirect antibody-forming cells and humoral antibodies.

Conjugation of DNA fragments to protein carriers by glutaraldehyde: immunogenicity of oligonucleotide-hemocyanin conjugates.

The practical realization of the concept of specific immunotherapy for systemic lupus erythematosus (SLE) has been hampered, thus far, by an inability to link DNA fragments to carrier protein. In this paper, a novel technique is described, in which glutaraldehyde is the linking agent. A 2-stage method was used to link oligonucleotides to a soluble protein carrier, such as keyhole limpet hemocyanin (KLH) or human gamma globulin (HGG), whereas a 1-stage technique was sufficient to link oligonucleotides to sheep red cells. Both the ultraviolet absorbance spectrum and diphenylamine assay demonstrated that oligonucleotides were coupled to soluble protein. The conjugate of oligonucleotide to protein carrier appears to be recognized by anti-DNA antibody since oligonucleotide linked to either KLH or HGG inhibited the binding of anti-DNA antibody in vitro, and oligonucleotide-coupled sheep cells are agglutinating by seropositve sera from lupus patients. In addition, oligonucleotide-KLH raised hemagglutinating antibody to denatured DNA in C57BL/6, DBA/2 or NZB mice, as well as IgG antibody as detected by SPRIA in C57BL/6 and DBA/2 mice. The significance of this new method for the development of an antigen specific therapy of SLE is discussed.

Tropical bont tick eradication campaign in the French Antilles. Current status.

The Amblyomma variegatum eradication campaign was officially started in April 1994 in Martinique and in Guadeloupe, including its dependencies of Marie Galante, Desirade and St Martin. A budget of $10.5 and $5.9 million for Guadeloupe and Martinique, respectively, was initially (1991) calculated and considered necessary to achieve the program. However, EEC, the most important donor, estimated that 75% only of this proposal was acceptable, on which it agrees to support a maximum of 50%. The balance had to be provided by French government, local political institutions, and animal owners. The current budget actualized in 1995 by veterinary authorities of Martinique and Guadeloupe is $7,200,000 and $9,900,000 respectively. The program will take 5 years: preparation (1 year), acaricide application (3 years), surveillance (1 year). During this first year, a pilot committee was established, and a project leader was designated for each island. Efforts were essentially oriented to organize the program in the field and to obtain funds from French and local counterparts. Funds allowed the recruitment and training of 19 new agents in Guadeloupe and 9 in Martinique, in addition to personnel already involved in the tick control program. Census of animal owners and identification of cattle started or were developed. Tenders were invited to provide vehicles and acaricides. For the latter, choices were made considering the prices and efficacy as well as funds available. Due to a limited budget and cost of pour-on formulations, pour-on acaricides will be used on a maximum of 30% of animals only. In order to investigate animal owners' reticences and the most appropriate media channels to establish a communication and a training program, a survey was conducted in Guadeloupe on a sample of 301 animal owners. The results are presented. In order to strengthen the chances of success of the campaign in the French islands, it is expected that a similar program will take place soon in infested neighboring islands.

Measurement of bottom versus charm as a function of transverse momentum with electron-hadron correlations in p + p collisions at square root of s = 200 GeV.

The momentum distribution of electrons from semileptonic decays of charm and bottom quarks for midrapidity |y|<0.35 in p+p collisions at square root of s=200 GeV is measured by the PHENIX experiment at the Relativistic Heavy Ion Collider over the transverse momentum range 2e(+/-)K(-/+)X (K unidentified) reconstruction. It is found that the yield of electrons from bottom becomes significant above 4 GeV/c in pT. A fixed-order-plus-next-to-leading-log perturbative quantum chromodynamics calculation agrees with the data within the theoretical and experimental uncertainties. The extracted total bottom production cross section at this energy is sigma(bb)=3.2(-1.1)(+1.2)(stat)(-1.3)(+1.4)(syst)mub.