116 research outputs found
Time to AIDS from 1992 to 1999 in HIV-1-Infected Subjects with Known Date of Infection.
To estimate the change in AIDS incubation time during three periods characterized by different availability of antiretroviral treatments, data from the French Hospital Database on HIV of 4702 HIV-1-positive subjects with a documented date of infection were analyzed. Times from seroconversion to AIDS were compared in three periods: period 1 from January 1992 to June 1995 (monotherapy); period 2 from July 1995 to June 1996 (dual therapy); and period 3 from July 1996 to June 1999 (triple therapy). Nonparametric survival analyses were performed to account for staggered entries in the database and during each period. From periods 1 to 3, antiretroviral treatments were initiated earlier after infection, more subjects were treated, and the nature of regimens changed (25.6% of subjects were treated with monotherapy in period 1, 34.6% were treated with dual therapy in period 2, and 53.4% were treated with triple therapy in period 3). Compared with period 1, the relative hazard (RH) of AIDS was 0.31 in period 3 (95% confidence interval [CI]: 0.24-0.39). When comparing period 3 with period 2, the RH of AIDS was 0.36 (CI: 0.29-0.45). Assuming a log normal distribution, the median time to AIDS was estimated as 8.0 years in period 1 (CI: 6.0-10.6), 9.8 years in period 2 (CI: 8.5, 11.2), and 20.0 years in period 3 (CI: 17.1-23.3). This lengthening in time to AIDS from 1992 to 1999 was particularly marked in the period after the introduction of triple therapy, including protease inhibitors
Evaluation of Clinical and Immunological Markers for predicting Virological Failure in a HIV/AIDS treatment cohort in Busia, Kenya
In resource-limited settings where viral load (VL) monitoring is scarce or unavailable, clinicians must use immunological and clinical criteria to define HIV virological treatment failure. This study examined the performance of World Health Organization (WHO) clinical and immunological failure criteria in predicting virological failure in HIV patients receiving antiretroviral therapy (ART)
On the Relativistic Description of the Nucleus
We discuss a relativistic theory of the atomic nuclei in the framework of the
hamiltonian formalism and of the mesonic model of the nucleus. Attention is
paid to the translational invariance of the theory. Our approach is centered on
the concept of spectral amplitude, a function in the Dirac spinor space. We
derive a Lorentz covariant equation for the latter, which requires as an input
the baryon self-energy. For this we either postulate the most general
Lorentz-Poincar\'e invariant expression or perform a calculation via a
Bethe-Salpeter equation starting from a nucleon-nucleus interaction. We discuss
the features of the nuclear spectrum obtained in the first instance. Finally
the general constraints the self-energy should satisfy because of analyticity
and Poincar\'e covariance are discussed
Role of the Nuclear and Electromagnetic Interactions in the Coherent Dissociation of the Relativistic Li Nucleus into the H + He Channel
The differential cross section in the transverse momentum and a total
cross section of mb for the coherent dissociation of a 3-A-GeV/
Li nucleus through the HHe channel have been measured on emulsion
nuclei. The observed dependence of the cross section is explained by the
predominant supposition of the nuclear diffraction patterns on light (C, N, O)
and heavy (Br, Ag) emulsion nuclei. The contributions to the cross section from
nuclear diffraction ( MeV/) and Coulomb MeV/)
dissociations are calculated to be 40.7 and 4 mb, respectively.Comment: ISSN 0021-3640, Pleiades Publishing, Ltd., 200
Neutron Stars and Nuclei in the Modified Relativistic Hartree Approximation
We have examined the properties of neutron-rich matter and finite nuclei in
the modified relativistic Hartree approximation for several values of the
renormalization scale, , around the standard choice of equal to the
nucleon mass . Observed neutron star masses do not effectively constrain the
value of . However for finite nuclei the value , suggested by
nuclear matter data, provides a good account of the bulk properties with a
sigma mass of about 600 MeV. This value of renders the effective three
and four body scalar self-couplings to be zero at 60\% of equilibrium nuclear
matter density, rather than in the vacuum. We have also found that the matter
part of the exchange diagram has little impact on the bulk properties of
neutron stars.Comment: 33 pages, Latex, 8 figures (available from authors by fax), Minnesota
preprint NUC-MINN-93/7-
Effects of Short Range Correlations on Ca Isotopes
The effect of Short Range Correlations (SRC) on Ca isotopes is studied using
a simple phenomenological model. Theoretical expressions for the charge
(proton) form factors, densities and moments of Ca nuclei are derived. The role
of SRC in reproducing the empirical data for the charge density differences is
examined. Their influence on the depletion of the nuclear Fermi surface is
studied and the fractional occupation probabilities of the shell model orbits
of Ca nuclei are calculated. The variation of SRC as function of the mass
number is also discussed.Comment: 11 pages (RevTex), 6 Postscript figures available upon request at
[email protected] Physical Review C in prin
Three-body dN interaction in the analysis of the 12C(pol_d,d') reaction at 270 MeV
We have measured the cross sections and analyzing powers Ay and Ayy for the
elastic and inelastic scattering of deuterons from the 0+(g.s.), 2+(4.44 MeV),
3-(9.64 MeV), 1+(12.71 MeV), and 2-(18.3 MeV) states in 12C at an incident
energy of 270 MeV. The data are compared with microscopic distorted-wave
impulse approximation calculations where the projectile-nucleon effective
interactionis taken from the three-nucleon t-matrix given by rigorous Faddeev
calculations presently available at intermediate energies. The agreement
between theory and data compares well with that for the (p,p') reactions at
comparable incident energies/nucleon.Comment: 17 pages, 3 Postscript figure
3D interconnection by FIB assisted Pt deposition and electroless nickel deposition on the sides and edges of an I-Seed
This paper reports on the development of a 3D interconnection process leading to the successful assembly of a five-layer 3-D 1mm cube module. This proof of concept module demonstrates the capability for successful integration and interconnection of commercial off the shelf components to fabricate functional modules in 1mm cube dimensions. It also demonstrates that use of established volume scale technologies like Flip-chip, dicing and patterning techniques are viable for fabricating these 1mm modules. The demonstrator consists of LED's bonded to the six sides of the 1mm cube, interconnected and powered up. The work will particularly report on two different processes to fabricate the interconnection pattern using direct Focused Ion Beam (FIB) assisted Pt deposition and electroless metal deposition, which again patterned by FIB. Uniform thickness of the deposit and excellent coverage on all six sides is achieved by electroless nickel deposition. Voltage current characterisation of the deposited Pt shows a resistivity value of 1864 +/- 100 mu Omega cm, whereas electroless Ni film shows a resistivity of 25 mu Omega cm due to boron inclusion. 100 nm An layer is deposited by chemical displacement reaction to enhance the conductivity and solderability of the film
Short and long term retention in antiretroviral care in health facilities in rural Malawi and Zimbabwe.
Despite the successful scale-up of ART services over the past years, long term retention in ART care remains a major challenge, especially in high HIV prevalence and resource-limited settings. This study analysed the short (<12 months) and long (>12 months) term retention on ART in two ART programmes in Malawi (Thyolo district) and Zimbabwe (Buhera district)
Microscopic theories of neutrino-^{12}C reactions
In view of the recent experiments on neutrino oscillations performed by the
LSND and KARMEN collaborations as well as of future experiments, we present new
theoretical results of the flux averaged and
cross sections. The approaches used are
charge-exchange RPA, charge-exchange RPA among quasi-particles (QRPA) and the
Shell Model. With a large-scale shell model calculation the exclusive cross
sections are in nice agreement with the experimental values for both reactions.
The inclusive cross section for coming from the decay-in-flight of
is to be compared to the experimental value
of , while the one due to
coming from the decay-at-rest of is which
agrees within experimental error bars with the measured values. The shell model
prediction for the decay-in-flight neutrino cross section is reduced compared
to the RPA one. This is mainly due to the different kind of correlations taken
into account in the calculation of the spin modes and partially due to the
shell-model configuration basis which is not large enough, as we show using
arguments based on sum-rules.Comment: 17 pages, latex, 5 figure
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