Hello everyone, I am doing an online survey through online panel of Amazon Mechanical Turk. how I can find a sample size formula not to be old?

I used Cochran (1963) sample size formula, but as it shows it so old and my advisor asks for some new references for finding an appropriate sample size.

01 February 2021 8,275 4 View

Does anyone know any article on free convection heat transfer from an oblate with uniform heat flux?

Does anyone know any article on free convection heat transfer from an oblate spheroid with uniform heat flux? All articles I've found are about isothermal oblates.

14 December 2020 1,163 4 View

How can I simulate electroporation for a bilayer?

hi I am trying to simulate electroporation for a bilayer containing 10% cholesterol on GROMACS. I have read lots of articles but the only parameter that they have talked about was the electric...

15 November 2020 7,602 2 View

How can I correct my electrostatic potential figure to be symmetric?

hi. I have done electrostatic potential analysis on a symmetric bilayer contains 10% Cholesterol but I've got this figure and I thought there is a problem with that as the potential is not...

09 November 2020 7,137 1 View

How should I make an index for gangle in GROMACS?

Hi. I'm analyzing a bilayer and I want to make an index for calculating tilt angle. my problem is I have no idea about how to create such an index which contains vectors in it. I would be...

01 October 2020 9,021 1 View

Regarding the EDS-mapping and the SEM-BS micrograph, how do you interpret those big grains?

Regarding the EDS-mapping and the SEM-BS micrograph, how do you interpret those big grains? Do you think those dark areas in mapping are caused by the geometry of the big grains so that the x-ray...

30 July 2020 8,669 3 View

How can I build a DMPC bilayer contains certain numbers of Cholesterol molecules on GROMACS?

Hi. I'm new to GROMACS and I want to simulate a DMPC bilayer contains 8 Cholesterol molecules. But I have no idea about how to add Cholesterol molecules to my simulation box.

07 July 2020 5,699 1 View

How can i resolve the size of nested-multiplex pcr?

Hi there, I have a problem to get a conclusion in my PCR results. I have nested-PCR product in which the first run size is what i expected to be. However, the second run is ~100nt larger than...

21 September 2018 3,901 5 View

How to optimize periplasmic protein expression in E.coli (BL21)?

I want to optimize protein purification. My protein is expressed in periplasmic space of E.coli. I particularly want to know what is the routine protocol for these kind of proteins. Is it 1mM...

16 July 2017 5,042 7 View

Hi everybody. I want to compute the percentage of women and men in a dichotomous variable for several years in my dataset. is there anyway to compute?

I have a dataset for several years, I want to find that how percentages of women and men select between yes or no in different years. Is it necessary to calculate year by year in SPSS or there is...

15 June 2017 1,941 3 View

Physics: Why do we describe light by referring to its wavelength, but microwaves and radar pulses by referring to their frequency?

In physics, the description of the properties of light generally refers to its wavelength (nm), while in the range of microwaves and radio waves we refer to the frequency of a signal (e.g. kHz or...

03 March 2021 1,682 3 View

Looking for Materials with high thermal expansion coefficient and high temperature resistance?

03 March 2021 8,272 1 View

Can we classify HV and LV lines based on line length?

I have dataset which shows the length of power lines. I need to classify the lines based on the line length. Is there a rule to classify the High voltage (HV) and low voltage (LV) lines based on...

03 March 2021 4,116 4 View

Can linear DNA be used as template for site-directed mutagenesis?

Is it possible to induce site-directed substitution mutation by quick-change method on linear dsDNA? or it has to be cloned in some vector? If yes, should it be treated with the Dpn1 enzyme...

03 March 2021 401 4 View

Waters 2707 HPLC autosampler problem?

I am using a 2707 waters HPLC device. When I try to inject a sample, it says missing plate or rack. I changed the needle and calibrated its position but I still get the same problem. I even get...

02 March 2021 1,408 1 View

Why almost every element would be metallized in sufficiently high pressure and low temperature?

(This statement is from wikipedia, BTW). What is so special about metallic bond that is limiting high-P low-T state of a matter (as long as individual atoms exist, not white dwarf of neutron star...

02 March 2021 3,309 2 View

Does anyone know HRM channel in a 2 plex QIAGEN Rotor- Gene Q qPCR can be used as a separate channel?

I am going to have 3 different probes in my qPCR work that I am going to do. But I realized that the machine we have in the lab is a Rotor-Gene Q 2plex HRM Platform, saying it has green, yellow,...

01 March 2021 8,544 1 View

I have designed reflectarray element and feeding it though Horn Antenna on HFSS. After full wave simulation, I am not getting desired results?

I have designed reflectarray element to generate OAM beams at 5.8GHz and feeding it though Horn Antenna on HFSS. After full wave simulation, i am not getting desired results i.e Radiation pattern...

01 March 2021 9,701 5 View

Where can I find atmospheric measurement profiles (temperature, density, etc.) between 300-800 km altitude?

I am investigating thermospheric mass density profiles between 300-800 km altitude. I would like to compare the variability with other parameters, including temperature, electron content,...

01 March 2021 5,902 3 View

Any research papers for extraction of nutrient deprivation on macroalgae? Analysed by HPLC-UV and GC/MS. Possibly from macroalgae genus Rhizoclonium?

I am doing my thesis on the nutrient deprivation on the macroalgae Rhizoclonium sp. I will be analysing the levels over a period of roughly 5 days by HPLC-UV and GC/MS. I will be using seawater as...

28 February 2021 6,477 1 View