Selecting particular columns from large datasets (csv) using R Studio?

So I have large number of csv files (100+) in a directory with same structure and column names. The data is in time series and there are approx 30 columns/file. However i only want to aggregate...

08 February 2021 245 5 View

Is it necessary to include orbital dynamics (translational) in attitude dynamics (rotational) problem?

I want to simulate satellite attitude control with a quaternion attitude representation. thrusters and reaction wheels are the main AOCS controllers. is it Ok to omit orbit dynamics (orbit...

31 January 2021 5,094 2 View

How much pre-PCR dilution of mixed-template DNA extracted from pollen (honey) is appropriate for Metabarcoding?

I'm working on pollen DNA metabarcoding to identify the floral composition of honey. How much pre-PCR dilution of mixed-template DNA extracted from pollen (honey) is appropriate for the...

28 December 2020 9,132 1 View

How to add two vertical and parallel Fresnel reflection coefficients to retrieve overall reflection coefficient for a right hand circular wave?

I have a problem in which a right hand circular polarized wave (GPS wave) encounters an ideal smooth plane obliquely, and then is reflected off that. To solve this kind of problems, the wave is...

28 December 2020 2,271 3 View

Which is better to focus on teaching or research for a good academic life and Why?

Which is better to focus on teaching or research for For a good academic life and Why?

26 December 2020 5,737 9 View

Is ag paste suitable for back contact on silicon wafer? or i should deposit al on the back surface using pvd or plasma sputtering?

Fabricating silicon solar cell

22 December 2020 4,906 7 View

Which renewable source is the best ?

wind hydro solar etc.

21 December 2020 6,360 16 View

Why is light pure energy?

light is pure because the light is the simplest electromagnetic construct but the energy of any object is also of the same kind.

20 December 2020 207 4 View

How to handle Missing Values for Skipped Questions (Systematic Missing) in R ?

10 December 2020 435 4 View

What is the best industrial emulsifier to make silicon oil in water emulsion?

I need to make long-lasting stable emulsions of 6 wt. % percent silicon oil in DI water. The previousely made emulsions using Tween and Span Emulsifiers did not remain stable after a week.

31 October 2020 3,568 3 View

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02 March 2021 3,060 3 View

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28 February 2021 9,936 2 View

When is it unnecessary to change organisational culture?

As a former management practitioner, I recall a generally accepted view that changing organisational culture is difficult, so you should only attempt it if the organisational change that you are...

27 February 2021 2,595 8 View

Does RNAiMAX transfection reagent work in serum free medium?

I diluted siRNA and RNAiMAX in opti-MEM and added to the cells which they were in the growth medium. Is it a right way? or should I culture cells in the opti-MEM medium for a while and not in...

26 February 2021 10,041 3 View

What is the best surface to culture cells isolated from a skin biopsy?

Hello, recently I am having some difficulties with maintaining the cell culture of primary cells isolated from a skin biopsy (normal and malignant). The coating of culture plates with Matrigel (a...

26 February 2021 6,151 2 View

Unknown debris sheets observed in cell culture flasks?

Hi, We culture neural progenitor cells in T175 culture flasks coated with PLO-Laminin. We have successfully grown these cells with our protocol for months. Recently, we observed large sheets...

25 February 2021 3,443 4 View

How to model Supercritical water gasification (SCWG) process in Homer software?

Hi everyone How to model Supercritical water gasification (SCWG) process in Homer software?

25 February 2021 4,075 1 View

Has anyone experienced changes in growth for cell culture when purchasing media from different companies?

I recently switched the company where we buy our DMEM/F12 and i have noticed a signficant change in growth for my human olfactory neurosphere cell lines

24 February 2021 2,268 3 View

Advice on growing lactobacillus species in the lab?

Hello everyone, For part of my PhD project, I'm hoping to grow some lactobacillus species in the lab so that I can create standard curves for a qPCR quantification of a faecal sample. However, I...

24 February 2021 3,157 6 View

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22 February 2021 9,932 11 View