Potential Negative VR Aspects – by Marc Armstrong

If you haven’t yet tried out real VR, I recommend you do so at your earliest opportunity. It really is one of those things that fall into the “you don’t understand unless you’ve tried it yourself” category. I had the lucky chance just recently, with a nearby friend having purchased a Playstation VR headset. Being a person whose job is based around online casinos, and online casinos going VR pretty soon, I felt it was best I tried out VR sooner, rather than later.

The overall experience I feel completely justified in describing as mind blowing. There was, however, a con to my VR journey that cannot be ignored. Namely that for the first half an hour it took a pretty major effort on my part to not land up with my face flat on the ground.

You see, I feel that many still don’t understand that VR has a profound impact on your brain. The VR world looks, for all intents and purposes, about as real as a digital world possibly can. The depth and feeling of space is astonishing.

The down side is, however, that your brain, rightly so, has real issues with suddenly not being able to place your body in this strange new world. In my own experience, a feeling of jarring disorientation set in upon looking down and seeing I didn’t have legs, or a body of any kind, for that matter.

It wasn’t that I personally didn’t understand I was seeing a VR world, but my brain, on the other hand, had some serious issues with the whole situation. I swayed about and had to keep taking small correctional steps, given that my sense of balance was all over the place. It got worse before it got better.

Uncontrolled Motion Disorientation

Seasickness is no laughing matter. It hits some people hard, reducing them to lumps of vomiting jelly, generally seen hanging over the side of the boat and making sounds like a feline ejecting hairballs. I haven’t experienced sickness on a boat, but understand that the effect is due to your brain being unhappy about the uncontrolled motion of the ocean. In my VR journey the disorientation got alarmingly worse upon controlling the character in the game, Resident Evil 7, for those interested.

The camera in the game is controlled by the right thumb stick, which sweeps the view around, as it generally does in games. In this case, however, given that the game is first person, it meant the view in front of your eyes sweeps about regardless of what your head is currently doing. For some. the result is overwhelming seasickness. For me, it was a sensation similar to finding myself unexpectedly in a washing machine on the spin cycle.

If this is all making you a bit resistant to the concept of VR, don’t fret. It turns out that brains are very adaptable and versatile. After about half an hour my brain gradually got used to the situation. After another half hour I was merrily scooting about in he VR world, with only minor, fleeting losses of balance. As a tip, it really helped if I stood with my leg touching the couch. This, apparently, grounded my brain.

After playing Resident Evil I tried out a simple VR slot game, and I’m happy to report that the disorientation was not nearly as striking. Given that the game didn’t require you to move from a single spot, there was never any disconnect between what my head was doing, and what I was seeing.

All in all the experience of a VR slot game was rather breathtaking, and the level of immersion so deep that I can honestly say I felt something close to VR induced euphoria. The game featured relaxing music and dazzling visuals, and overall I feel I could’ve stayed in that happy little place for hours. All I can say is that if a simple slot game was this enjoyable in VR, an online poker game in VR will be something seriously worth looking forward to.


potentially negative closed

I have this issue. I have tried everything. ValidateRequest="false".. and decoding and encoding html.. etc. etc..

What I need is a popup box (so im using ModalPopupExtender) to present to a user where people can type in xml settings and click ok/cancel button to close the popup and save.

However i keep on getting this error "A potentially dangerous Request.Form value was detected from the client"..

Here is my test code below (quick example of my scenario and error)..


What it means by the negative symbol in the zeta potential magnitude?

I am curious to know what doest the negative symbol means. The measured zeta potential value for the copolymer that I synthesized is -48 mV. I am not sure on few possibilities for the observation of the negative symbol. Is it possible to be due to the usage of anionic surfactant or it is an indication of the presence of acidic components in the emulsion medium since the measured pH for this emulsion is 2 or due to the dissolution of acidic monomers at the particle surface. Could someone please advice me on this regard? And please do comment on the activity of the Na+ (from the SDS surfactant) upon completion of the synthesis. Will the surfactant still surround the polymer particle or otherwise. Thanks a lot. Hoping for a guidance. Thanks a lot.

The liquid layer surrounding the particle exists as two parts; an inner region (Stern layer) where the ions are strongly bound and an outer (diffuse) region where they are less firmly associated. Within the diffuse layer there is a notional boundary inside which the ions and particles form a stable entity. When a particle

moves (e.g. due to gravity), ions within the boundary move it. Those ions beyond the boundary stay with the bulk dispersant. The potential at this boundary (surface of hydrodynamic shear) is the zeta potential (f. The magnitude of the zeta potential gives an indication of the potential stability of the colloidal system. If all the particles in suspension have a large negative or positive zeta potential then they will tend to repel each other and there will be no tendency for the particles to come together. However, if the particles have low zeta potential values then there will be no force to prevent the aggregation. Use below mention link for your solution

The liquid layer surrounding the particle exists as two parts; an inner region (Stern layer) where the ions are strongly bound and an outer (diffuse) region where they are less firmly associated. Within the diffuse layer there is a notional boundary inside which the ions and particles form a stable entity. When a particle

moves (e.g. due to gravity), ions within the boundary move it. Those ions beyond the boundary stay with the bulk dispersant. The potential at this boundary (surface of hydrodynamic shear) is the zeta potential (f. The magnitude of the zeta potential gives an indication of the potential stability of the colloidal system. If all the particles in suspension have a large negative or positive zeta potential then they will tend to repel each other and there will be no tendency for the particles to come together. However, if the particles have low zeta potential values then there will be no force to prevent the aggregation. Use below mention link for your solution

Hi dr, Thanks a lot for the reply. I understand the principle as you mentioned. But my doubt here is, what the negative symbols indicates? I am not mentioning about the magnitude but why am i getting a negative symbol instead of positive sign. Is the negative symbol representing the anionic surfactant that surrounds the polymer particles or due to the carboxylated anion (due to the presence of AA). The pH of this emulsion is 2. Could you please explain about this, dr. Thanks a lot.

From the physics point of view, the -ve zeta potential can occur in two cases: i) when the solute is -ve or ii) due to charge inversion (overcharging) when the solute is +ve. The second case happens typically at high ionic strength solutions or when multivalent cations are present. The pH is only 2, which implies ion concentration of 0.01 M. This is not high enough for charge inversion. Then the only left choice is the -ve solute. From what you mentioned, the anionic surfactant that tightly binds to the polymers imparts negative charge on the surface of the solute. I am coming from Physics background with little chemistry knowledge. Am I correct in assuming that the surfactant binds tightly to the polymer? In that case, the -ve anionic surfactant generates -ve potential. The positive ions in the solution adsorb on top of the anionic surfactant due to the -ve potential as well as due to volume exclusion effects. The first layer of +ve ions (in your case, either H+ or Na+ ions) are said to adsorb specifically (Stern layer). The +ve ions screen the -ve charge on the surface of the solute and as a result the potential gradually goes to zero far from the solute. But it is always -ve.

Carboxylic groups as the source of negative charge are out of the question at pH 2, as carboxylic pKa values are generally around 4 or above and they thus are at least 99% in undissociated (avid) form at pH 2. pKa of suplhonate is around 2 so the polar end group of sodium dodecyl sulphonate (SDS) will be about 50% dissociated at pH 2. Thus, this surfactant will confer a negative charge to a hydrophobic polymer particle by adsorption at pH 2. Specific adsorption of sodium ions will be negligible.

why zeta potential and electrophoretic mobility negatively increases with increasing the concentration of same ionic composition at a fixed pH?

it is due to preferential adsorption of ions. Read about lattice ion hydration and potential determining ion (PDI).

The negative symbol in front of the zeta potential means that the net charge of the scattering object (including up to the slipping plane) is negative. Different materials have different isoelectric points, and it is very typical to see a negative charge above the isoelectric point IEP of the sample.

An alternative potential explanation may be that the data quality is such that you are looking at noise, thermal drifts due to Joule heating, or multiple scattering, especially if the negative value is quite close to zero.