Fiat lux!

Photochemistry made the transition from a natural observable to a scientific discipline in the latter half of the 19; th; Century CE. This short article looks at the development of the discipline in its first 100 years with a particular emphasis on the participation of Swiss scientists

Fiat lux!

Презентація до доповіді, виголошеної під час святкування Міжнародного дня світла в ТНТУ 16.05.2019 року.ех. була б спонсорська підтримка..

Fiat lux – Shedding new light on derivatives markets.

Not so long ago, we policymakers thought we knew just what challenges we were facing for Europe to better take advantage of globalisation through a more sustainable model: these were climate change and a rapidly ageing society. However, since 2007 we have also learnt that there was another area requiring a deep sustainability check: the financial system. What started in 2007 as a credit crisis in the US market for subprime mortgages turned into a full-blown global fi nancial crisis in 2008, following Lehman’s default and has taken us near to a sovereign debt crisis as countries face the fiscal consequences of financial instability, on top of large public indebtedness. This highlights the importance of the financial system for society as a whole and, therefore, the political imperative of mending it so that finance serves the real economy – not the other way around. We therefore need to put in place a new set of rules and principles ensuring a stable and sustainable financial system. Without this our whole economy will be impeded from prospering again and we will not be able to address the challenges outlined above.

TPC track distortions III: fiat lux

We present a comprehensive overview and final summary of all four types of static track distortions seen in the HARP TPC, in terms of physical origins, mathematical modelling, and correction algorithms. 'Static'Â distortions are defined as not depending on the event time within the 400 ms long accelerator spill. Calculated static distortions are compared with measurements from cosmic-muon tracks. We characterize track distortions by the r phi residuals of cluster positions with respect to the transverse projection of a helical trajectory constrained by hits in the RPC overlap regions. This method provides a fixed TPC-external reference system (by contrast to the co-moving coordinate system associated with a fit) which solely permits to identify individually, and measure quantitatively, the static TPC track distortions arising from (i) the inhomogeneity of the solenoidal magnetic field, (ii) the inhomogeneity of the electric field from the high-voltage mismatch between the inner and outer TPC field cages, (iii) the anode-wire durchgriff, and (iv) a homogenous ion-charge density in the drift volume. Five voltage levels are identified which were set incorrectly during data taking with the HARP TPC, and unfortunately conspired toward large static and dynamic track distortions. The observed time development of static distortions after a 83mKr calibration lends decisive support to our conclusions on static TPC distortions

Fiat lux, lux in tenebris, fiat lux et pereat mundus

No nosso mundo há uma imagem que certifica e outra que ilude, há a transparência e a opacidade. Similitudes do ser e do não-ser. Da antiguidade clássica até aos dias de hoje a luz sempre foi portadora de um fenómeno de múltiplas interpretações nos mais variados contextos e tem sido um instrumento valioso na procura de saberes cada vez mais ricos. Neste projeto a luz funciona como metáfora para os conceitos de princípio e fim, nascimento, morte e vida, visível e invisível, oculto e conhecido, entre outras dualidades que todos temos dentro de nós. É preciso estar atento aos sentidos, pois eles “apenas” mostram a aparência das coisas, é preciso vislumbrar aquilo que está por detrás das aparências e das transformações. A partir de experiências mais ou menos tautológicas, exploram-se as potencialidades da “matéria imaterial” que está inevitavelmente na base do trabalho. A ação é uma necessidade. Em todos os momentos presenteiam-se obras em processo em que o participante é também autor das obras, por influenciar, dar a sua interpretação e construir o momento do presente, num eterno fluir. Sendo o presente ano o Ano Internacional da Luz, é de relevância aprofundar o espaço que a luz ocupa

Fiat Lux, Let There Be Light!

Most of us think of light as helping us see things, but it is so much more important than that. Light is electromagnetic energy moving in waves through space, interacting with atoms and molecules as it goes. So are radio waves, microwaves, infrared light, ultraviolet, x-rays and gamma rays - all of them are electromagnetic energy, and the only real difference is the spacing between the wave crests. So light gives us communications with each other with radio and TV, and it gives us the ability to travel through the universe using telescopes and our imagination. But light also gives us access to scientific questions, such as: what holds the atoms and molecules together? How does the mysterious quantum mechanics work? And understanding all these, how can we build electronic devices for modern life? And if we are very ambitious, we build accelerators like the Large Hadron Collider, and particles collide and concentrate electromagnetic energy into tiny spaces, and according to Einstein's E equals mc squared, we turn energy into new particles to learn, perhaps what the universe was like when it was a tiny fraction of a second old

Fiat Lux: the effect of illuminance on acuity testing

PURPOSE: To determine the effect of changing illuminance on visual and stereo acuity. METHODS: Twenty-eight subjects aged 21 to 60 years were assessed. Monocular visual acuity (ETDRS) of emmetropic subjects was assessed under 15 different illuminance levels (50–8000 lux), provided by a computer controlled halogen lighting rig. Three levels of myopia (−0.50DS, −1.00DS & 1.50DS) were induced in each subject using lenses and visual acuity (VA) was retested under the same illuminance conditions. Stereoacuity (TNO) was assessed under the same levels of illuminance. RESULTS: A one log unit change in illuminance level (lx) results in a significant change of 0.060 LogMAR (p < 0.001), an effect that is exacerbated in the presence of induced myopic refractive error (p < 0.001). Stereoacuity scores demonstrate statistically significant overall differences between illuminance levels (p < 0.001). CONCLUSIONS: The findings of this study demonstrate that changes in illuminance have a statistically significant effect on VA that may contribute to test/retest variability. Increases in illuminance from 50 to 500 lx resulted in an improved VA score of 0.12 LogMAR. Differences like these have significant clinical implications, such as false negatives during vision screening and non-detection of VA deterioration, as the full magnitude of any change may be hidden. In research where VA is a primary outcome measure, differences of 0.12 LogMAR or even less could affect the statistical significance and conclusions of a study. It is recommended that VA assessment always be performed between 400 lx and 600 lx, as this limits any effect of illuminance change to 0.012 LogMAR