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

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

Carbon Emission calculation factors ?

I am thinking about writing a paper on carbon emissions based on electricity consumption data from some buildings. From a research perspective, which factors should i specially focus while...

09 October 2020 4,142 3 View

What kind of fluid could I use for a pitfall trap that also does not invalidate molecular testing?

Hi, I want to start testing pitfall trap to obtain ants samples, but I need to conduct molecular analysis on those insects. So, what kind of fluid can I use? Ethanol expires too early and I need...

03 March 2021 5,978 5 View

Difficulty in cloning of 1kb gene into vector?

I am facing difficulties in cloning a 1kb gene into a vector (pJIT163). I have my gene on interest (GOI) in pUC57 and want to clone in pJIT163 using SalI and BamHI restriction sites. I am getting...

25 February 2021 3,221 7 View

Is it harmful to breed for Cre Homozygosity initially?

Hello, I am currently using a Cas9 knock in system that will be expressed in the liver. To do so STOP codon fl/fl Cas9 KI mice were bred with Albumin-Cre mice to generate heterozgous pups, that...

24 February 2021 5,759 3 View

Alternatives to traditional cloning of insert into backbone (dsDNA)?

Hi, I am stuck with a cloning experiment: The insert & backbone(bb) share one compatible end at 3' end(NotI) and one incompatible end at 5' end (XbaI for insert; HindIII for backbone). So i...

16 February 2021 1,664 3 View

Can part of recombinant protein not be expressed?

Hello. I am currently trying to express a recombinant gene with Avitag at the N-terminal. I'm aiming at a final product that looks like this: Avitag-(target protein) The protein I use is already...

14 February 2021 2,039 4 View

Transformation into the Stbl3 chemo competent cells?

03 February 2021 1,111 5 View

What is the best way and technique for serial dilution of bactria to get accurate number of colony ?

Hello I am infecting cells with bacteria in a well and then I am doing serial dilution of this well 1 in 10 and culture the two last dilution on MHA agar I have difficulty in getting accurate...

26 January 2021 9,256 5 View

Good day, I have not been able to amplify the plasmid Frt-hspB1. Somebody could give an advice me?

I acquired the plasmid in Addgene, reconstituted the filter paper where the plasmid comes from with 30 microliters of TE buffer pH 8, immediately afterwards perform the transformation of E.coli...

25 January 2021 2,526 3 View

Has someone used TTC agar overlay method and can help me?

I have tried to use TTC agar overlay method for a few times to identify respiratory-deficient yeast which were affected by EthBr. The problem is that cells which should have stayed white also have...

22 January 2021 585 10 View

I am having trouble with cloning my gene. How can I fix this?

16 January 2021 6,566 8 View