Abstract We construct a Zika transmission model to investigate the effect of postponing pregnancy on infection intensity. perform analytical and numerical investigations for deterministic stochastic analysis obtain basic reproductive ratio, endemic state, probability disease extinction, outbreak. The results indicate that by reducing rate mosquito-to-human ratio increases, and, consequently, in...

day biodiversity, estimated to comprise more than 100 million species, has developed in around 4,000 million years on the basis of the ability of life forms to adapt and multiply at a rate that surpassed extinctions. Species, including humans, depend on the ecosystems that have operated with no or minimal human intervention up to recent years. Recent extinction rates are 100–1,000 times their p...

We report a wide-field imaging method to rapidly and quantitatively measure the optical extinction cross-section σ(ext) (also polarisation resolved) of a large number of individual gold nanoparticles, for statistically-relevant single particle analysis. We demonstrate a sensitivity of 5 nm(2) in σ(ext), enabling detection of single 5 nm gold nanoparticles with total acquisition times in the 1 m...

Periods of oceanic anoxia have had a major influence on the evolutionary history of Earth and are often contemporaneous with mass extinction events. Changes in global (as opposed to local) redox conditions can be potentially evaluated using U system proxies. The intensity and timing of oceanic redox changes associated with the end-Permian extinction horizon (EH) were assessed from variations in...

Fear conditioning and extinction are behavioral models that reflect the association and dissociation of environmental cues to aversive outcomes, both known to involve the lateral amygdala (LA). Accordingly, responses of LA neurons to conditioned stimuli (CS) increase after fear conditioning and decrease partially during extinction. However, the long-term effects of repeated fear conditioning an...

We have simultaneously modeled both the interstellar extinction and polarization (both linear and circular) on the basis of a trimodal dust model: large silicate core-organic refractory mantle dust particles; very small carbonaceous particles responsible for the hump extinction; and PAH’s responsible for the FUV extinction. The core-mantle particles which are the exclusive contributor to the in...

We report BV R surface photometry of a lenticular galaxy, NGC 4753 with prominent dust lanes. We have used the multicolor broadband photometry to study dust-extinction as a function of wavelength and derived the extinction curve. We find the extinction curve of NGC 4753 to be similar to the Galactic extinction curve in the visible region which implies that the sizes of dust grains responsible f...

We evaluated four methods for increasing the practicality of functional communication training (FCT) by decreasing the frequency of reinforcement for alternative behavior. Three participants whose problem behaviors were maintained by positive reinforcement were treated successfully with FCT in which reinforcement for alternative behavior was initially delivered on fixed-ratio (FR) 1 schedules. ...

We report optical extinction properties of dust for a sample of 26 early-type galaxies based on the analysis of their multicolour CCD observations. The wavelength dependence of dust extinction for these galaxies is determined and the extinction curves are found to run parallel to the Galactic extinction curve, which implies that the properties of dust in the extragalactic environment are quite ...

We present a proof-of-concept study that dust extinction curves can be extracted from the infrared (IR), optical, ultraviolet (UV), and X-ray afterglow observations of GRBs without assuming known extinction laws. We focus on GRB 050525A (z 1⁄4 0:606), for which we also present IR observations from the Spitzer Space Telescope at t 1⁄4 tIR 2:3 days postburst. We construct the spectral energy dist...