The use of methods from the physical sciences to aid in the study of biological systems. Note that biophysics questions are only allowed if they are mainly about physics.

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How can plants rooted on the ground become charged?

According to a quote on the physics forum "Plants are usually charged negatively and emit weak electric fields." Reference However this seems to contradict the fact that plants are grounded and any ...
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64 views

Electromagnetic fields and human behaviour

To what extent does electromagnetic fields and/or radiation from space have influence on human behaviour and/or physiology?
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347 views

Would there be EMF induced in our body due to electromagnetic radiations?

The experiments of innovative Faraday and Joseph Henry in USA, conducted around 1830, demonstrated conclusively that electric currents were induced in closed coils when subjected to changing magnetic ...
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56 views

Cesium-137 From Fukushima Meltdown

I've been reading up on the Fukushima nuclear meltdown and its effects it had on the environment. The iodine-131 initially released from the incident decayed after 8 days, but other isotopes such as ...
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1answer
30 views

Relation of Force and Energy, from a biophysics point of view

Considering us humans practically, does energy require force, ie we do apply some internal and external forces to do work, or does force require energy. ie we can only apply a force on an object if we ...
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393 views

Remote EEG detection / reading

I recently noted that Philips, Accenture, and Emotive grouped together to create a proof of concept that would assist ALS patients to gain greater control of their lives through brain, voice, and eye ...
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Could we recognise if time was running at a different rate for one species than another? I.e a human and an ant

My question is quite simple if time ran at a different speed for smaller creatures, how would we be able to observe this or confirm by experiment?
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What is the different between Poisson Nernst–Planck and Poisson Navier–Stokes in the Electrolyte?

I am now studying about electroosmosis flow phenomena which is governing by the Navier-Stokes equation and Poisson equation. By combine these two equation we can describe the electrolyte flow velocity ...
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37 views

Generallized Canonical Ensemble - Isobaric Ensemble

I am trying to understand the way generalized canonical ensembles like the pressure ensemble are derived from the standard canonical ensemble. In the derivation for the standard form, one defines a ...
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1answer
47 views

An impossible relationship between variables

This book chapter defines $CV$ as follows: $$ CV^2 = 2\pi\nu^2\int^\frac{V_{th}-V_{ss}}{\sigma_V}_\frac{V_{r}-V_{ss}}{\sigma_V}dxe^{x^2}\int^x_{-\inf}dye^{y^2}(1 + erf(y)) $$ However, Figure 15.2 in ...
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51 views

Trapping time and site population

In thr article environment assisted quantum transport, the trapping time probability for the FMO complex, a measure of the energy transfer efficiency, is defined $2\kappa_3\int^\infty_0 dt\langle ...
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138 views

The difference in how temperature feels inside in the summer vs. in the winter?

72 degrees feels cooler when it's hotter outside, say 90 F but warmer if it's really cold outside, say 32F However it also feels different if it's 90 vs say 70F outside. Why is that?
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Does this method of predicting the ratio of translational diffusion coefficients for a sphere and a sheet, work?

Imagine that I have a spherical particle of molecular weight $M$, volume $V$, and some experimentally observed center-of-mobility translational diffusion coefficient $D_{sphere}$ in water. I take ...
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Fluctuation spectrum of lipid bilayer membranes

I am interestend in calculating the fluctuation spectrum of a thermally fluctuating 2d membane which is only subject to a surface tension $\sigma$. ($\mathcal{H}=\sigma\int\mathrm{d}A$) Depending in ...
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62 views

Understanding quantum coherence in biological processes (Magnetoreception)

Moved my questions to the top. Context below. Why is the strength of the electric field and the coupling constant being compared to the inverse coherence time? What is the inverse coherence time? Is ...
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87 views

How does the Darma - Smart Cushion work? Explanation of the new fiber loop ring-down spectroscopy

How does the Darma - Smart cushion monitor your sitting position and obtain the breathing rate, body movements, and BCG (Ballistocardiography) signals? The creators say that they accomplish this by ...
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60 views

What happens to proteins under x ray/gamma ray radiation?

A simple question to which I am yet to find an answer. I have not found any papers which would go into detail about it, there is some stuff on protein damage in x-ray crystallography but they are ...
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76 views

Medical/Physics Question - Cut Off Finger Preservation

This question might require some knowledge of medical/tissue, but physicists seem to know everything, so figured I've give it a shot here ;) When people put cut off fingers they are told to put the ...
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181 views

How much energy (eV) is in a mosquito's wing beat?

We're all familiar with the annoying sound of a mosquito near our ear. I estimate the wing beat frequency to be in the 400 to 800Hz range (to accomodate the Bruce Willis and Danny de Vito of mosquitos ...
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Why do our eyes only pick up electromagnetic radiation which has been classified as visible light?

My understanding: Electromagnetic radiation is carried via photons - which enter our eyes and activate receptors depending on the amount of energy the photons have when hitting them. At what point do ...
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Effects of light wavelength on the Hamiltonian of the FMO complex

Recently, I have been interested in the energy transfer within the FMO complex. I was wondering, how could the wavelength of the light that excites the complex affect the energy transfer efficiency. ...
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79 views

If we increase the aperture of a telescope and decrease its magnification, can it be harmful to the eyes?

The full moon is the brightest object in the night sky. I believe that if we increase the aperture of the objective, and decrease the magnification of the telescope, it might concentrate a dangerous ...
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0answers
59 views

Why are flight feathers asymmetric?

I've always heard that flight feathers were asymmetric because the shape generates lift, like an airplane wing airfoil shape. But, the feathers are not oriented with the shaft perpendicular to the ...
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The needs of photonic senseor for biomedical applications

I am doing a literature review on the topic mentioned in the title. When I write the review, I found myself a contradiction. Just want to listen to opinions from others :P Nowadays, the development ...
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Matter and Electrical Impulses

The human brain is composed of about 100 billion neurons; with trillions of synapses. These synapses transmit signals, which is obviously made of some sort of matter. This is what creates thought and ...
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Validity of a steady state solution of reaction-diffusion equation

I am performing a simulation involving growth of bacteria. This is an agent-based simulation where the solutes (glucose, oxygen etc.) are represented as a concentration field discretised over space, ...
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Suppose we fill a membrane with ferro fluid, and alter the magnetic field around it in specific ways, what dynamics can come into play?

im trying to develop a flexible robotic arm filled with ferro fluid. Different flexible motions can be performed using this concept.
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Modeling Acoustic Lubrication

I thought about posting this question in the Biology StackExchange site but really it is just the application of my question that applies to biology not the core of the question itself. Can anyone ...
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52 views

Reference request: finding a biophysics paper about super time resolution imaging of a neuron firing

About a year ago I attended a talk at the University of Ottawa. The author described a method for achieving super time resolution images of a neuron firing. From what I can recall, the group found a ...
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Concentration of Proteins

You release a billion protein molecules at position $x = 0$ in the middle of a narrow capillary test tube. The molecules’ diffusion constant is $10^{−6} \ cm^2 s^{−1}$. An electric field pulls ...
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109 views

Visualise the sound intensity

I'm studying Biophysics and my current subject is sound. One of the properties of sound is intensity. From my notes I can see the following definition: Intensity Formula is: $(I = w*m^{-2})$ or $(I = ...
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Height estimate by step profile?

With so many current apps in mobiles tracking number of steps based on analyzing the accelerometer's measurements in time during a walk, I was wondering the following: Would it be possible to ...
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18 views

Hiccup in frequency domain

Main question: What would the Fourier transform of hiccup look like? This question is too general so let me elaborate a few possible approaches. Hiccup just as a series of pulses (of no matter what ...
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19 views

Electric dipole moment of a coaxial cable?

Question Does a cylindrical coaxial cable have a net electric dipole moment, and if so why? Context I am trying to understand why the heart has a net electric dipole moment. In the heart we have ...
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Confusion regarding interpretation of a diffusion related PDE?

So I was reading Keller & Segel paper related to mathematical model of cellular aggregation in slime molds. In the model (considering 2D assumption) we have an equation like below: ...
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Will increased air pressure increase efficiency of solute diffusion into a membrane?

Biophysics question: I have a container with a biological tissue inside of solution where the solute slowly diffuses across the membrane and binds inside of the tissue. If I were to put this unsealed ...
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66 views

The mathematical physics of saltatory neuron action potential transmission

Some time ago, I tried to understand saltatory electrical potential transmission on a myelinated axon but have not found a clear mathematical model of this mechanism. I understand the cable theory, ...
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0answers
17 views

Seeking help on simplified mathematical (biophysical) model of serpentine locomotion in viscoelastic environment

I'm trying to build a mathematical model of C. elegans locomotion under overdamped viscous environment. In order to simplify this problem, I use six discrete pieces of rigid cylinders to represent ...
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Would a $50\: \mathrm{Hz}$ spinning magnetic plate in front of a human generate harmful current?

We know that spinning magnetic plate will generate current inside any wire. so if we stand before 50Hz spinning magnetic plate, then, does that 50Hz spinning magnetic plate in front of us (human body ...