A Review on Management of Amblyopia

Amblyopia is a visual cortex neurodevelopmental condition cause am vision abnormalities during childhood. It is one of the most typical causes of vision loss at an early age. It occurs due to abnormal development of the visual cortex. The part receiving signals from the diseased eye does not receive it correctly and thus develops abnormally. This abnormal development during the critical period of growth of child results in brain damage. Depending on its aetiology the types of amblyopia are Strabismic amblyopia, Visual deprivation amblyopia, Anisometric, Ametropic, Meridional, Toxic amblyopia. Clinical features are visual acuity is reduced, the effect of neutral density filter, the Crowding phenomenon is present. Complications of amblyopia include a Lazy eye becoming weak permanently, the eye may move out from the visual axis (squints). When treating amblyopia, our goal is that the eyes will work together in unison at an equal level; this will create a clear vision in the lazy eye. Amblyopia is treated in various ways depending on the seriousness of the disease and the patient's age. Patching of the non-amblyopic eye, as well as treatment with drugs like atropine, are common treatments. Vision therapy and some modifications to spectacles and contact lenses have been discovered to be effective in treating amblyopia in recent years. Modern Treatment- Falling Blocks, Occlu-pad. With current breakthroughs in amblyopia therapy, the success rate of a multimodal strategy is also improving. The purpose of this review article is to present information on the management of amblyopia. Literature on AMBLYOPIA MANAGEMENT has been taken from PubMed, Scopus, Science Direct, and other internet resources.

A Novel Flow Cytometric Approach for the Quantification and Quality Control of Chlamydia trachomatis Preparations

Chlamydia trachomatis is an obligate intracellular pathogenic bacterium with a biphasic developmental cycle manifesting two distinct morphological forms: infectious elementary bodies (EBs) and replicative intracellular reticulate bodies (RBs). Current standard protocols for quantification of the isolates assess infectious particles by titering inclusion-forming units, using permissive cell lines, and analyzing via immunofluorescence. Enumeration of total particle counts is achieved by counting labeled EBs/RBs using a fluorescence microscope. Both methods are time-consuming with a high risk of observer bias. For a better assessment of C. trachomatis preparations, we developed a simple and time-saving flow cytometry-based workflow for quantifying small particles, such as EBs with a size of 300 nm. This included optimization of gain and threshold settings with the addition of a neutral density filter for small-particle discrimination. The nucleic acid dye SYBR® Green I (SGI) was used together with propidium iodide and 5(6)-carboxyfluorescein diacetate to enumerate and discriminate between live and dead bacteria. We found no significant differences between the direct particle count of SGI-stained C. trachomatis preparations measured by microscopy or flow cytometry (p > 0.05). Furthermore, we completed our results by introducing a cell culture-independent viability assay. Our measurements showed very good reproducibility and comparability to the existing state-of-the-art methods, indicating that the evaluation of C. trachomatis preparations by flow cytometry is a fast and reliable method. Thus, our method facilitates an improved assessment of the quality of C. trachomatis preparations for downstream applications.

Investigation of Thermal Stress Arising in a Graphene Neutral Density Filter for Concentrated Photovoltaic System

As an excellent heat spreader candidate, graphene attracts considerable interest concerning its application in concentrated photovoltaic (CPV) systems. The consequences of employing a graphene-coated neutral density (GCND) filter to mitigate concentrated light impact adequately. Hence, the temperature for a concentrated photovoltaic system is reported in this work. A systematic thermal characterisation study was carried out using three different thickness-based GCND filters. Interestingly, using the GCND filter, the focal spot temperature remained considerably lower than that of the incident temperature for a more extended period. The graphene coating orientation further influenced the temperature gradient behaviour of the focal spot and incident temperature. The thermal and electrical results depended on the GC samples’ thickness and emplacement, leading to dramatic differences in their respective photovoltaic performance. As a base substrate of the GCND filter, the low-iron glass suffered extreme thermal stress under concentrated solar irradiance. This thermal stress phenomenon on the GCND filter was further analysed. This study suggests that using GCND leads to lower temperature maintenance of the CPV focal point, which minimises the PV cell thermal stress. However, the GCND filter also experienced considerable thermal stress during the CPV experiment.

Multi-photon attenuation-compensated light-sheet fluorescence microscopy

Attenuation of optical fields owing to scattering and absorption limits the penetration depth for imaging. Whilst aberration correction may be used, this is difficult to implement over a large field-of-view in heterogeneous tissue. Attenuation-compensation allows tailoring of the maximum lobe of a propagation-invariant light field and promises an increase in depth penetration for imaging. Here we show this promising approach may be implemented in multi-photon (two-photon) light-sheet fluorescence microscopy and, furthermore, be achieved in a facile manner utilizing a graded neutral density filter, circumventing the need for complex beam shaping apparatus. A “gold standard” system utilizing a spatial light modulator for beam shaping is used to benchmark our implementation. The approach will open up enhanced depth penetration in light-sheet imaging to a wide range of end users.

A yellow filter improves response times to low-contrast targets and traffic hazards

Purpose: Anecdotal evidence suggests that some sunglass users prefer yellow tints for outdoor activities such as driving, and research has suggested that such tints improve the apparent contrast and brightness of real-world objects. The aim of this study was to establish whether yellow filters resulted in objective improvements in performance for visual tasks relevant to driving.Methods: Response times of nine young (age 31.4 ± 6.7 years) and nine older (age 74.6 ± 4.8) adults were measured using (a) video presentations of traffic hazards (driving hazard perception task), and (b) a simple low-contrast grating which appeared at random peripheral locations on a computer screen. Response times were compared when participants wore a yellow filter (with and without a linear polariser) versus a neutral density filter (with and without a linear polariser). All lens combinations were matched to have similar luminance transmittances (approximately 27%). Results: In the driving hazard perception task, the young but not the older participants responded significantly more rapidly to hazards when wearing a yellow filter than with a luminance matched neutral density filter (mean difference 450 ms). In the low-contrast grating task, younger participants also responded more quickly for the yellow filter condition but only when combined with a polariser. Although response times increased with increasing stimulus eccentricity for the low-contrast grating task, for the younger participants this slowing of response times with increased eccentricity was reduced in the presence of a yellow filter, indicating that perception of more peripheral objects may be improved by this filter combination. Conclusions: Yellow filters improve response times for younger adults for visual tasks relevant to driving.