The response of cone photoreceptors to light is stable and reproducible because of the exceptional regulation of the cascade of enzymatic reactions that link visual pigment (VP) excitation to the gating of cyclic GMP (cGMP)-gated ion channels (cyclic nucleotide-gated [CNG]) in the outer segment plasma membrane. Regulation is achieved in part through negative feedback control of some of these re...

Reaction times for incremental and decremental stimuli were measured at five suprathreshold contrasts for six retinal illuminance levels where rods alone (0.002-0.2 Trolands), rods and cones (2-20 Trolands) or cones alone (200 Trolands) mediated detection. A 4-primary photostimulator allowed independent control of rod or cone excitations. This is the first report of reaction times to isolated r...

A new endmember extraction method has been developed that is based on a convex cone model for representing vector data. The endmembers are selected directly from the data set. The algorithm for finding the endmembers is sequential: the convex cone model starts with a single endmember and increases incrementally in dimension. Abundance maps are simultaneously generated and updated at each step. ...

In this paper, we introduce a cone generalized semi-cyclicφ−contraction maps and prove best proximity points theorems for such mapsin cone metric spaces. Also, we study existence and convergence results ofbest proximity points of such maps in normal cone metric spaces. Our resultsgeneralize some results on the topic.

BACKGROUND Accurately quantifying key interactions between species is important for developing effective recovery strategies for threatened and endangered species. Whitebark pine (Pinus albicaulis), a candidate species for listing under the Endangered Species Act, depends on Clark's nutcracker (Nucifraga columbiana) for seed dispersal. As whitebark pine succumbs to exotic disease and mountain p...

PURPOSE Short-wavelength automated perimetry (SWAP) has gained popularity as a clinical tool for the assessment of short-wavelength-sensitive (S)-cone visual function, but has also been shown to have higher threshold variability than conventional achromatic perimetry, possibly due to an imbalance between S-cone adaptation and long (L)- and medium (M)-wavelength-sensitive cone adaptation. To inv...

PURPOSE We determined the relative contributions of rods, cones, and melanopsin to pupil responses in humans using temporal sinusoidal stimulation for light levels spanning the low mesopic to photopic range. METHODS A four-primary Ganzfeld photostimulator controlled flicker stimulations at seven light levels (-2.7 to 2 log cd/m(2)) and five frequencies (0.5-8 Hz). Pupil diameter was measured ...

Leber congenital amaurosis (LCA) caused by mutations in Aryl hydrocarbon receptor interacting protein like-1 (Aipl1) is a severe form of childhood blindness. At 4 weeks of age, a mouse model of LCA lacking AIPL1 exhibits complete degeneration of both rod and cone photoreceptors. Rod cell death occurs due to rapid destabilization of rod phosphodiesterase, an enzyme essential for rod survival and...

Axon guidance by graded diffusible ligands plays an important role in the developing nervous system. Concentration gradients induce an asymmetric localisation of molecules in the axon tip, the growth cone, and the consequent internal polarised signalling pathway leads to rearrangement of the growth cone cytoskeleton and, ultimately, to motility. Here the authors provide a mathematical descripti...

The study of a pair of single Dielectric Barrier Discharge (DBD) plasma actuator which is placed on the surface near the apex of a cone-cylinder body with a semi-apex angle of 10° is presented. The two SDBD plasma actuators are aligned on the cone at azimuth angle θ = ±90° symmetrically and sustained by a repetitive high voltage nanosecond pulses generator. The pressure distribution over the te...