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's the best way to measure growth rates in House sparrow chicks from day 2 to day 10?

What's the best way to measure growth rates in House sparrow chicks from day 2 to day 10? Since, the growth curve from day 2 to 10 won't be like the "Logistic curve" it might not follow logistic...

03 March 2021 1,401 3 View

After a reference from Int J Body Compos Res, can any body help?

Hi, I am after the reference below, my library says it cannot obtain a copy either locally or internationally, any help appreciated! Chris Wang ZM, Heshka S, Wielopolski L, Pi-Sunyer FX, Pierson...

03 March 2021 6,193 1 View

What techniques can I use to determine the miscibility of polymer blends?

The term miscibility refers to the single-phase state in thermodynamics. I do not mean the compatibility of different components. To determine the miscibility I know several techniques such as...

03 March 2021 4,107 4 View

Sample dilution for quantitative analysis using ELISA?

If the detection range is in ng/ml but the reference range is in ug/ml for a molecule or protein in serum or plasma .how to dilute and what is the initial volume to be taken for quantitative analysis

02 March 2021 7,670 3 View

How to repeat an operation on an atom selection for multiple times in PyMol?

Hi, I am trying to construct a multi-layer fibril structure from a single layer in PyMol by translating the layer along the fibril axis. For now, I am able to use the Translate command in PyMol...

02 March 2021 4,569 4 View

Which is a lucid standard comprehensive book to guide on psychological scale construction and its standardization?

02 March 2021 7,082 3 View

Shall I skip the measurement model in SmartPLS?

Hello everyone, I had run a mediation model in SmartPLS using questionnaires that were already validated among my statistical population. A professor who edited my paper -though she is not...

01 March 2021 3,052 3 View

What is involved in morphological changes of SEM images of a substance?

In the sem analysis of CaCO3 nanaoparticles, the morphology images showed spherical shaped particles but the proposed morphology for these type of nanoparticles is trigonal. I prepared the...

01 March 2021 1,960 4 View

Joint behaviour in Abaqus is not captured well?

I am working on roof joint and trying to simulate the behaviour in Abaqus. I am successful in running the model but the final graph does not follow the experimental curve in the negative direction...

01 March 2021 6,661 3 View

Could you please recommend some good journal that accept very long revie papers (approximately 6000+ words) in neurosurgery, cancer biology ?

Could you please recommend some good journal that accept very long revie papers (approximately 6000+ words) in neurosurgery, cancer biology ?

01 March 2021 8,087 3 View