Initial ranging scheme based on interpolated Zadoff-Chu sequences for OFDMA-PON.

Initial access to passive optical networks (PONs) requires upstream (US) synchronization of multiple optical network units (ONUs). We propose a low-complexity scheme for orthogonal frequency division multiple access (OFDMA) based PONs and demonstrate it experimentally. The scheme is based on interpolated Zadoff-Chu sequences, to synchronize the signal of each ONU arriving at the optical line terminal (OLT).

Adaptive nonlinear Volterra equalizer for mitigation of chirp-induced distortions in cost effective IMDD OFDM systems.

We report experimental validations of an adaptive 2nd order Volterra equalization scheme for cost effective IMDD OFDM systems. This equalization scheme was applied to both uplink and downlink transmission. Downlink settings were optimized for maximum bitrate where we achieved 34 Gb/s over 10 km of SSMF using an EML with 10 GHz bandwidth.

Geographical distribution and diversity of bacteria associated with natural populations of Drosophila melanogaster.

Drosophila melanogaster is one of the most widely used model systems in biology. However, little is known about its associated bacterial community. As a first step towards understanding these communities, we compared bacterial 16S rRNA gene sequence libraries recovered from 11 natural populations of adult D.

Alternative measures of response to Pseudomonas aeruginosa infection in Drosophila melanogaster.

Studies of invertebrate immune defence often measure genetic variation either for the fitness cost of infection or for the ability of the host to clear the parasite. These studies assume that variation in measures of resistance is related to variation in fitness costs of infection. To test this assumption, we infected strains of the fruit fly, Drosophila melanogaster, with a pathogenic bacterium.

Cultural factors in exercise participation of older adults.

Participation motives were investigated in 81 Australian-born and 42 overseas-born older Australians (M age = 67.8 yr.) involved in community-organised exercise programs.

Isogeneic versus allogeneic antiserum in the prophylaxis of experimental rabies.

With a view to establishing whether rabies antiserum derived from a species genetically identical to a challenged recipient would increase or decrease its effectiveness compared with that of allogeneic antiserum, rabies immune sera produced in an inbred strain of mice and in donkeys were tested, either alone or with a course of vaccine inoculations, in mice of the same strain a few hours after intramuscular challenge with fixed CVS rabies virus. Surviving mice were bled at intervals over a year and the rabies antibodies assayed in pooled sera.There was no evidence that the isogeneic antiserum was either more or less effective than the allogeneic, nor was there a difference between the two in the decay of passive antibody; similarly, there was no marked difference in their ability to interfere with the active production of antibody resulting from the highly potent vaccine used.

Rabies neutralizing antibody response to different schedules of serum and vaccine inoculations in non-exposed persons. 4.

Early and persistent antibody is needed for maximum protection to be afforded to persons severely exposed to rabies. With vaccine alone, detectable antibody production takes 7-10 days, and the passive antibody introduced with antirabies serum or gamma-globulin is commonly used to fill this gap. However, administration of antirabies serum or gamma-globulin with vaccine interferes with the antigenic action of the vaccine.

Mutants of simian virus 40 differing in plaque size, oncogenicity, and heat sensitivity.

Takemoto, K. K. (National Institute of Allergy and Infectious Diseases, Bethesda, Md.

Heat-labile serum factor required for immunofluorescence of polyoma tumor antigens.

The immunofluorescent demonstration of polyoma tumor antigens in tumor cells requires a heatlabile serum component. With unheated hamster tumor serum, specific fluorescence was observed in polyoma-transformed hamster, mouse, and rat tumor cells. Heated serum usually gave little or no reactivity; the activity of such heated serum could be restored simply by the addition of fresh normal unheated hamster serum.