When paramyxovirus genome was exposed to UV light, the level of inhibition of transcription was proportional to the distance from the leader sequence.

When DNAse liberates nucleotides from dsDNA, the bases are no longer stacked as they are in dsDNA, so that orbital overlap is minimized and UV absorbance increases.

When UV light or X-ray is absorbed by matter, electrons are excited from core levels into unoccupied states, leaving empty core states.

When opaque, liquid crystal or electrochromic smart glass blocks most UV, thereby reducing fabric fading ; for SPD-type smart glass, this is achieved when used in conjunction with low emissivity coatings.

When BKV celebrated its 50 years of service, an elaborate " UV Day " parade was one of the items.

When such exposure is unavoidable, preventative measures must be taken to control UV radiation, including the use of blinds, shades, curtains, UV filtering films, and UV-filtering panels in windows or cases.

When the UV index is greater than 3 ( which occurs daily within the tropics and daily during the spring and summer seasons in temperate regions ) adequate amounts of vitamin D < sub > 3 </ sub > can be made in the skin after only ten to fifteen minutes of sun exposure at least two times per week to the face, arms, hands, or back without sunscreen.

When a picture frame is expected to be exposed to direct sunlight, or harsh lighting conditions such as fluorescent lights, UV filtering may be added to slow down the photocatalytic degradation of organic materials behind picture framing glass.

When the UV source is removed, the molecules gradually relax to their ground state, the carbon-oxygen bond reforms, the spiro-carbon becomes sp³ hybridized again, and the molecule returns to its colorless state.

When heated by the laser, the metal re-radiates this energy as diffuse x-rays, which are more efficient than UV at compressing the fuel pellet.

When a single photon is sent through an interferometer, it passes through both paths, interfering with itself, as waves do, yet is detected by a photomultiplier or other sensitive detector only once.

When an electron in an excited molecule or atom descends to a lower energy level, it emits a photon of light equal to the energy difference.

When the emission of the photon is immediate, this phenomenon is called fluorescence, a type of photoluminescence.

When the emission of the photon is delayed, the phenomenon is called phosphorescence.

When the photon is emitted at a distance equal to the Schwarzschild radius, the redshift will be infinitely large.

When the photon is emitted at an infinitely large distance, there is no redshift.

When such an electron decays without external influence, emitting a photon, that is called " spontaneous emission ".

When an electron meets a hole, it falls into a lower energy level, and releases energy in the form of a photon.

When this happens due to the presence of the electromagnetic field from a photon, a photon is released in the same phase and direction as the " stimulating " photon, and is called stimulated emission.

When it was found in 1900 by Max Planck that the energy of waves could be described as consisting of small packets or " quanta ", Albert Einstein further developed this idea to show that an electromagnetic wave such as light could be described as a particle ( later called the photon ) with a discrete quantum of energy that was dependent on its frequency.

When an X-ray photon collides with an atom, the atom may absorb the energy of the photon and boost an electron to a higher orbital level or if the photon is very energetic, it may knock an electron from the atom altogether, causing the atom to ionize.

When sodium or its compounds are introduced into a flame, they turn it yellow, because the excited 3s electrons of sodium emit a photon when they fall from 3p to 3s ; the wavelength of this photon corresponds to the D line at 589. 3 nm.

When such an electron decays without external influence, emitting a photon, that is called " spontaneous emission ".

When an atom is probed by an external mechanism, such as a photon or a beam of electrons with energies in the range of 2 keV to 50 keV, a core state electron can be removed leaving behind a hole.

When these are absent, however, optical detection is said to be " photon noise limited " as only the shot noise ( also known as " quantum noise " or " photon noise " in this context ) remains.

When a photon of sufficient energy strikes the diode, it excites an electron, thereby creating a free electron ( and a positively charged electron hole ).

When two nanowires acting as photon waveguides cross each other the juncture acts as a quantum dot.

When an electron and a hole recombine, it is possible for a photon to be emitted.

When the molecule relaxes it emits a photon and it returns to a different rotational or vibrational state.

When words can be used in a more fresh and primitive way so that they strike with the force of sights and sounds, when tones of sound and colors of paint and the carven shape all strike the sensibilities with an undeniable force of data in and of themselves, compelling the observer into an attitude of attention, all this imitates the way experience itself in its deepest character strikes upon the door of consciousness and clamors for entrance.

When the plague strikes, he finds himself trapped in a city with which he feels he has no connection.

When Young's career began, pitchers delivered the baseball underhand and fouls were not counted as strikes.

When the key is pressed, the tangent strikes the strings above, causing them to sound in a similar fashion to the hammering technique on a guitar.

When light strikes a material, most of the light is absorbed while a smaller amount of a particular frequency or wavelength is reflected.

When the hammer strikes, the head gets stopped by an opposite force coming from the target ; which is equal and opposite to the force applied by the head to the target.

When the colonial administration rejected the People's Assembly's recommendations, Nkrumah organized a " Positive Action " campaign on 01 January 1950, including civil disobedience, non-cooperation, boycotts, and strikes.

When ionizing radiation strikes a semiconductor, it may excite an electron out of its energy level and consequently leave a hole.

When a wave strikes a reflective surface, it changes direction, such that the angle made by the incident wave and line normal to the surface equals the angle made by the reflected wave and the same normal line.

When a returning reflection strikes another discontinuity, some of the signal rebounds in the original signal direction, creating multiple echo effects.

When the second mallet strikes the bar the first mallet is removed.

When a hollow-point hunting bullet strikes a soft target, the pressure created in the pit forces the material ( usually lead ) around the inside edge to expand outwards, increasing the axial diameter of the projectile as it passes through.

When Perseus arrives in Larissa, he participates in some funeral games and accidentally strikes Acrisius on the head with a discus, killing him and fulfilling the prophecy.

When ionizing radiation strikes the tube, some of the molecules of the fill gas are ionized, either directly by the incident radiation or indirectly by means of secondary electrons produced in the walls of the tube.

When Hymir refuses to provide Thor with bait, Thor strikes the head off Hymir's largest ox to use as his bait.

When whites used economic retaliation local Blacks seeking school integration in 1956 after the US Supreme Court ruling declaring segregation in public schools to be unconstitutional, students came to their support with hunger strikes, boycotts, and mass marches.

When Perry took over in 1994, the Bosnian Serbs were besieging Sarajevo, the Bosnian capital, but the Serbs were forced to draw back in face of a UN ultimatum and warning of air strikes.

When a clavichord key is pressed, a small metal tangent strikes a string and remains in contact with it for as long as the key is held down.

When the fee goes up to two bars, Farwell strikes DeCruz with the gold bricks, killing him.

When a bowler bowls two strikes in succession, within a game, the bowler has scored a " double ".

When a bowler bowls three strikes in succession, within a game, the bowler has scored a " triple " ( also called a " turkey ").

When light strikes a charged photocathode plate, electrons are emitted through a vacuum tube that strike the microchannel plate that cause the image screen to illuminate with a picture in the same pattern as the light that strikes the photocathode, and is on a frequency that the human eye can see.