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

In DFT or HF, is it more expensive to calculate the H matrix or to diagonalize it?

I was wondering: in common DFT (or Hartree-Fock) algorithms/codes, and in particular in solving the Roothan equation, what is the most computationally expensive part: 1- evaluate all the terms of...

01 February 2021 396 2 View

How can solve the second order linear homogeneous partial differential equation with variable coefficients?

can someone help me with reduced the partial differential equation du/dt = - f(x) d^2 u/ dx^2 - g(x) du/dx --- (1) to become: du/dt = - p(x) d^2 u/ dx^2...

21 January 2021 3,296 1 View

IHC-paraffin experiment: how do you approach shopping for an antibody?

Hello everyone! I am shopping for an arginase 1 antibody to use for IHC-paraffin experiments with rat tissue. So far what I have understood is that if an antibody says it is reactive with rat,...

16 January 2021 794 3 View

Warning in Lavaan, variance-covariance not positive definite!, model is not identified?

Dear colleagues, I am new to R, I have been using Amos for conducting CFA but came to learn that when dealing with Likert scale, Lavaan in R is a better tool to do such analysis. I started using...

30 December 2020 5,608 3 View

Do you think that the president in Iraq should be able to change the economic situation?

13 December 2020 7,193 3 View

How to explain insignificant independent variable which is significant with interacting (Moderation) variable?

10 December 2020 3,037 1 View

What could be the impediments to the initiatives adopted by the bank towards FI in the Indian scenario?

this question from case Union Bank of India: Initiatives towards IT-enabled Financial Inclusion

09 December 2020 7,721 3 View

Can we use the general hotplate as a source of heating in the Soxhelt method or not ? what is optimal temperature when using n-hexane as a solvent?

there is a problem with the heating part in soxhelt apparatus, so my question can we use the standard hot plate as a source of heating?

05 December 2020 9,322 2 View

How can i figure out whether nanoparticles in my synthesis crosslinked or not?

i prepare protein nanoparticles. in one of my synthesis i use trifle amount of crosslinker and the nanoparticles stick in the bottom of plate. how can i understand that nanoparticles become...

03 December 2020 559 8 View

Enhanced Yellow Fluorescent Protein (Aequorea victoria) DNA sequence?

I am on the lookout for the Enhanced Yellow Fluorescent Protein (Aequorea victoria) DNA sequence. Does anyone know where I can find it? Thank you in advance

03 March 2021 3,568 1 View

Which bacteria are suitable for quorum sensing screening?

I want to find a quorum sensing inhibitor from plant extracts. Klebsiella pneumoniae, Moraxella catarrhalis, Staphylococcus aureus, and Streptococcus pneumoniae. I looked for these strains...

01 March 2021 7,675 3 View

Is it possible for two human neuronal cell lines to have different gene sequence for the same protein?

I am looking at the ATP1A2 (Sodium/Potassium ATPase alpha subunit 2) in two human neuronal cell lines. Expression levels of this protein seems to be almost equal when detected by one antibody....

01 March 2021 3,607 3 View

Runs of nucleotides in Sanger sequencing?

I performed site directed mutagenesis, transformation, and then I sent out plasmids for Sanger sequencing and found out that there is extension of DNA just before the stop codon. I am not sure...

27 February 2021 547 3 View

Has anyone used the Illumina ITS1 primer sets?

Hi everyone, Illumina provides a list of primers to amplify with high taxonomic coverage the ITS1 region for further fungal sequencing, but I cannot find the exact amount necessary of each...

25 February 2021 6,969 3 View

Errors in DNA sequences?

I am trying to better understand the scope of DNA replication and sequencing errors, e.g. 1. I have seen similar error rates of 10e4 to 10e5 for cell & instrumental DNA replication,...

24 February 2021 4,397 3 View

Is it efficient to do liquid biopsy to investigate the gene expressions of the tumor?

To do liquid biopsy and look for specific gene expressions there are so many published papers. Thera are different protocols and procedures used to isolate circulating cell free RNA or mRNA from...

23 February 2021 7,326 5 View

Is it possible that Cancer cells could survive in heparinized blood for 48 hours?

Hi everyone, I am just wondering if we incubated 200 microliter of whole blood with 50 microliter of cancer cells(1bout 5000cells) do you think that cancer would survive for 48 hours?

23 February 2021 3,840 3 View

I can detect my protein but the encoding DNA sequence has stop codons within. Should I ignore the stop codons?

I constructed a synthetic DNA library (scFv, VH-VL orientation) with a 3' reporter and 8x histag. I cloned and expressed this gene following which I performed an ELISA. The ELISA results suggested...

19 February 2021 7,006 5 View

What is the significance of (isolated) high titers of IgG anti GD1a antibodies in an older patient with polyneuropathy?

Remote history of Campylobacter infection with reactive arthritis, and Spitz nevus (UMP). Arthropod exposure in Zika/ChikV endemic area prior to emergence of length dependent, sensory PN with...

18 February 2021 8,719 1 View