No abstract

Loop quantum gravity is considered to be one of the two major candidates for a theory of quantum gravity. The most appealing aspect about this theory is it predicts that spacetime is not continuous; both space and time have a discrete nature. Simply, space is not infinitely divisible, but it has a granular structure, and time does not flow continuously like a smooth river. This paper demonstrates a review for two missed (unnoted) observations that support the discreteness of the spacetime. The content of this paper does not validate the specific model of quantized geometry of the spacetime which is predicted by the theory itself. Instead, it proves that time does not flow continuously. But it flows in certain, discrete steps, like a ticking of a clock, due to a simple observation which is absence of any possible value of time that can exist between the present and the future. Regarding space, it validates the spatial discreteness, and the existence of spatial granules (space quanta) due to a simple observation which is the existence of the origin position in a coordinates system. All of this is achieved by reviewing the concept of discreteness itself, and applied directly to the observations.

A new aspect of unification is presented in this paper. This aspect depends on two postulates of our recent theory concerning light propagation in a specific medium. The special theory of relativity is demonstrated as a reflection of our first postulate, regarding the existence of multiple, equivalent rest frames in our medium. The second postulate is concerned with energy forms in nature, and it deals with the quantum behavior of light and wave behavior of matter. By using this postulate, we are able to justify the existence of these two phenomena. As a consequence of this, gravity as described by general relativity is unified as a background-independent interaction under the same postulate.

Objectives: 1) to undertake a review of the literature to provide information to clinicians and trainees about the epidemiology, treatment and most importantly, prevention, of trachoma - the leading infectious cause of blindness worldwide. 2) To highlight the diagnosis and treatment of this preventable infectious eye disease for trainees and to evaluate the efficacy of the SAFE treatment and prevention strategy endorsed by the WHO as the target trachoma elimination year of 2020 nears.  Methods: A review of the literature was undertaken. PubMED, Clinical Key, UpToDate and Google Scholar databases were searched using the following MeSH terms and keywords: trachoma, infectious eye disease, chlamydia trachomatis, SAFE, community prevention.  Results: The diagnosis of trachoma is typically clinical and is made by identifying the signs of conjunctival inflammation and scarring, trichiasis and corneal opacification in the context of a trachoma-endemic region.  Randomized controlled trials have demonstrated the efficacy of the WHO’s SAFE (Surgery, Antibiotics, Facial Cleanliness, Environmental change) treatment and prevention strategy, the implementation of which has been associated with declining rates of trachoma worldwide.

Einstein’s theory of general relativity describes the gravitational field around massive objects ( like Earth) as a curvature in the spacetime. But it leaves the following question unanswered; why is the spacetime curved by a mass? Through a theory that has been introduced recently, regarding a medium for a light propagation, a simple answer is introduced. It depends on redefining the rest energy for a massive object ( like a planet) as new form of kinetic energy. For a static and spherically symmetric object, with a specific radius(