Magnetoliposomes as model for signal transmission

Liposomes containing magnetic nanoparticles (magnetoliposomes) have been extensively explored for targeted drug delivery. However, the magnetic effect of nanoparticles movement is also an attractive choice for the conduction of signals in communication systems at the nanoscale level because of the simple manipulation and efficient control. Here, we propose a model for the transmission of electrical and luminous signals taking advantage of magnetophoresis. The study involved three steps. Firstly, magnetite was synthesized and incorporated into fusogenic large unilamellar vesicles (LUVs) previously associated with a fluorescent label. Secondly, the fluorescent magnetite-containing LUVs delivered their contents to the giant unilamellar vesicles (GUVs), which were corroborated by magnetophoresis and fluorescence microscopy. In the third step, magnetophoresis of magnetic vesicles was used for the conduction of the luminous signal from a capillary to an optical fibre connected to a fluorescence detector. Also, the magnetophoresis effects on subsequent transmission of the electrochemical signal were demonstrated using magnetite associated with CTAB micelles modified with ferrocene. We glimpse that these magnetic supramolecular systems can be applied in micro- and nanoscale communication systems.

Relativistic and Newtonian Shock Breakouts

Observations of the first light from a stellar explosion can open a window to a wealth of information on the progenitor system and the explosion itself. Here I briefly discuss the theoretical expectation of that emission, comparing Newtonian and relativistic breakouts. The former takes place in regular core-collapse supernovae (SNe) while the latter is expected in SNe that are associated with gamma-ray bursts (GRBs), extremely energetic SNe (e.g., SN2007bi) and white dwarf explosions (e.g., type Ia and .Ia SNe, accretion induced collapse). I present the characteristic observable signatures of both types of breakouts, when spherical. Finally, I discuss Newtonian shock breakouts through wind, which produce a very luminous signal, with an X-ray component that is weak around the breakout, and becomes brighter afterwards.

On a method of avoiding collision at sea

I have in the foregoing paper already described a method of finding distances at sea in fog or thick weather. It is desirable to briefly recapitulate here the principle involved. signals travelling at differing rates are simultaneously sent out from the lighthouse or signal station. Thus there might he a sub-marine sound along with an aërial; or, again, a wireless signal along with an aërial sound; or, finally, the combination might he the sound in water and the wireless signal. Such simultaneously emitted signals become relatively displaced as they are propagated outwards. After travelling a distance of one nautical mile a sound in air will lag behind a sound in water by a time interval amounting to about 4.3 seconds. And an aërial sound will lag behind a wireless or a luminous signal as much as 5.5 seconds in the mile. Hence as the lag continues to increase at these rates per mile, the observation of the interval separating the reception of the signals on the ship will enable the navigator to "determine his distance from the signal station. It is obvious that similar methods will enable the mariner to tell the distance of another vessel, An error so great as one half second corresponds with an error of only 90 fathoms in the ease of the most sensitive combination—that is wireless signal and aërial sound.