Can polymer concentrations be calculated based on the number average molecular weight?

Hello, I spin-cast two different polymers onto wafers and measure their height as a function of initial concentration. For polymer A, I have the weight-average molecular weight (Mw) as well as...

28 February 2021 7,882 2 View

Can two EC50 values with different hill slopes be compared?

Hello, I fit a classical dose response curve Y=Bottom + (Top-Bottom)/(1+10^((LogEC-X)*HillSlope)) to my data (not related to inhibitors etc). The model I use is purely qualitative but it fits...

23 February 2021 8,155 5 View

Why is my protein not binding to my reversed-phase column?

Hello everyone! Short facts: I am trying to perform reversed-phase chromatography via a desalting column (Waters: Sep-Pak tC18 3cc) of an already purified hydrophobic protein to exchange the...

01 February 2021 5,471 15 View

Metabolomics Data Normalisation?

Hello, Setting: We have a rather large dataset consisting of somewhat 500 samples containing metabolomics data. The data was obtained by analysing dry capillary blood using HPLC methods, yielding...

04 January 2021 8,773 5 View

How does PEG lower the evaporation rate of water?

04 November 2020 4,643 6 View

Does the rate of water condensation depend on vapor pressure?

25 October 2020 5,108 3 View

Why does surface roughness enhance (super)hydrophobicity?

Hello, according to Wenzel's model, an increase in surface roughness will also increase the contact angle, but what is the thermodynamic reason for it? Considering the lotus effect, does a...

22 October 2020 9,004 8 View

Nonlinear fit to median instead of mean values?

Hello, my question might be more theoretical. The datasets I currently analyse are not normally distributed (according to shapiro-wilk and kolgomorov-smirnov @ p = 0.05). Therefore, I prefer...

24 September 2020 6,473 8 View

Initialization of Simulink Model in the course of an optimization loop gets slower?

I am performing an optimization, where in a Simulink Model (involving Matlab function blocks and discrete event blocks amongst other typical blocks) block parameters are changes by an optimization...

17 August 2020 4,904 4 View

Can maximum metabolic rate and Specific dynamic action coefficient be measured at the same time?

We are conducting a respirometer trial with salmonids and want to access SDA variables in relation to temperature. We are wondering, if we can measure the Maximum metabolic rate (MMR) and the...

12 May 2020 4,286 1 View

Is it possible to do piezoelectric coupling in ANSYS-APDL or COMSOL between tapered substrate and rectangular piezoelectric patch?

How to do Piezoelectric coupling in ANSYS-APDL or COMSOL between tapered substrate and rectangular piezoelectric patch? Piezoelectric coupling between the rectangular substrate and rectangular...

02 March 2021 9,833 3 View

Energy minimization in LAMMPS using NVT ?

How do I do energy minimization in lammps with NVT ensemble ? I am using the following command and it does not seem to work. It stops at extremely high energy and gives me the error zero search...

01 March 2021 2,294 3 View

Why is the sum of the elements in a row in a Q matrix equal to zero?

When explaining substitution models, the substitutions are expressed as Q matrix. Why is the sum of the elements in a row zero?

28 February 2021 3,864 3 View

Can we recognize signs of the "volatility clustering" property of a time series in its time domain plot?

My purpose is to recognize the volatility clustering property without statistical tests such as The Lagrange Multiplier (LM) test.

24 February 2021 4,150 3 View

Why the CHi^2 is close to zero with a bad fitting but the Rp and Rwp are still high?

I am refining my XRD data using in FullProf program. The intensity of the modulated X-ray peaks is almost flat. I tried to adjust the peak intensities but unsuccessful. What is the reason? I guess...

23 February 2021 2,304 4 View

Can we use a compensation matrix with single staining that the negative population for each single staining is below zero?

Recently we used single staining to make a compensation matrix. But, for each single staining we saw that 13 to 25 percent of our negative population had been shown below Zero. In this situation...

21 February 2021 9,982 2 View

How to overcome convergence issues in concrete arch models?

Hi, I have modelled a three-span arch bridge with soil fill over along with pedestals. The FE modelling is done in LUSAS with HX8M solid elements (i.e. 3D solid modelling). The non-linearity is...

20 February 2021 1,346 2 View

How to compare means of continuous data with zero-inflation and skew?

I have two groups (unpaired) of plant biomass measurements and want to know whether there is a test that can be used to determine statistical significance where assumptions are not violated. The...

18 February 2021 1,258 4 View

How can you tell if your organotypic slice culture is healthy ?

I'm working on organotypic cerebellar slice cultures from postnatal rats and I'm not sure how to tell if the slices are healthy at any given point. I know there should be a lot of microglial...

15 February 2021 2,830 2 View

What does it mean if in mediation analysis the indirect effect is significant but is a larger b value than that of the direct effect?

I understand that for partial mediation to have occured the CI for the indirect effect must not cross zero and the b value for the indirect effect should be smaller than the b value for the direct...

14 February 2021 3,273 7 View