What are the factors influencing O- versus N- alkylation of amides (straight chain or cyclic)?

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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

Can I use a protein-devoid condition as my negative control in ELISA?

Hello, I am running a sandwich-type ELISA where I am trying to inhibit a protein-protein interaction using small molecules. For each experiment, I determine my Z' (Z-prime) to determine the...

23 February 2021 7,429 1 View

Will SARS-CoV-2 Spike be broken into S1 and S2 by denaturing conditions?

Hello, I am performing a western blot of my SARS-CoV-2 Spike-pseudotyped lentiviral particles. I denature my virus by adding concentrated virus to 2X Laemmli buffer at 1:1, then boiling for...

17 February 2021 4,844 4 View

What is the best temperature to coat an ELISA plate?

Hello, I want to control the temperature of my ELISA plate during incubations to get consistent results. In general, what is the best temperature to coat the plate with antibody? I have been...

16 February 2021 2,377 7 View

SPSS - Merging files by ID numbers that contain letters?

Hi, I'm trying to merge files from a data base of 20 files, each containing about 4000 subjects. Unfortunately the ID numbers are actually a combination of numbers and letters (e.g., b1458219)....

15 February 2021 5,833 3 View

How would I go about getting an expert review on the interview questions for the dissertation?

Good Evening, My name is David Marshall and I am Doctor of Management Student at Colorado Technical University Online. I just recently received approval from the IRB to start data collection on...

08 February 2021 346 7 View

How can I quantify the color of a solution?

I know colorimetry has been the standard way by way of measuring the concentration of a particular compound (solute) in a colored solution (solvent or measure quantities of a particular compound...

08 February 2021 2,673 1 View

ACE2 Blotted as a double band?

Hello, I have recently run a western of Vero cells for ACE2. I detected ACE2 at the correct size, but it presents as a double band. The sample was prepared by lysing cells in 1X Laemmli...

07 February 2021 6,973 3 View

SARS-CoV-2 Spike Protein Western Bands?

Hello, I am western blotting SARS-CoV-2 spike protein from lentiviral using an antibody against S1. To prepare samples, I mixed concentrated lentivirus 1:1 with 2X Laemmli buffer and boiled...

07 February 2021 3,643 4 View

How does DMSO percentage affect ELISA?

Hello, In my sandwich-type ELISA which is testing for small molecule inhibition of a protein-protein interaction, it seems that DMSO percentage and dilution protocol are important. I...

31 January 2021 6,771 1 View

What element is driving the different slop in the low frequency tail?

My study consists simple corrosion inhibitors in salty brine. Right now I just fit my circuit with randles with CPE. Just wondering how the slop can given more info of the experiment. Or any...

01 March 2021 6,474 3 View

In Molecular Dynamics Simulation, how do I make changes to the force field according to my protein?

Hi In Molecular Dynamics Simulation, how do I make changes to the force field according to my protein? I got this error in the add-ion stage: Fatal error "./ amber99sb-ildn-HHH.ff / force...

01 March 2021 8,747 4 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

What is a good reagent for lentiviral plasmid transfection in HeLa cells?

I have been using Lipofectamine 2000 but was hoping there may be a better protocol or one for something like Lipofectamine PLUS reagent.

24 February 2021 1,633 4 View

Why does the sum of reaction forces not match the force component of a Free Body Cut in Abaqus?

I am using Abaqus to simulate a plate with in-plane loading. The boundary conditions allow the right edge to move up and down, the displacements on the left edge are fixed. There is no rotation...

23 February 2021 711 3 View

HPLC baseline failure (ACN/Water)?

My baseline increases without any explanation, it is only fixed by changing the solution B, will it be the column? Reagents? Bomb? Detector? Solution A: H3PO4 0.01% IN WATER Solution B: H3PO4...

21 February 2021 5,656 3 View

How to include additional force field in GROMACS?

I have a cellulose model system that is best described by the GLYCAM06 force field according to the literature. However, the set of force fields included in the GROMACS package doesn't include the...

20 February 2021 3,309 3 View

Which transfection reagent is the best for plasmid transfection of MDA-MB-231 cell line, Lipofectamine based or other reagent suggestion?

I try to transfect MDA MB 231 cell line with a plasmid by PEI, unfortunately, the rate of transfection is low, and now I wanna find and order the best transfection reagent for this cell line and...

19 February 2021 828 6 View

Any information about dinitrosalisylic acid reagent end point color stability ?

I work on estimation of alpha amylase activity using dinitrosalisylic acid reagent If i put the reagent to stope the enzymatic reaction and allow the reagent to react with the produced reducing...

17 February 2021 7,402 4 View

Has anyone performed a colorimetric RT-LAMP assay using Lucigens LavaLAMP kit?

Hi there, my lab recently opted to use LavaLAMP from Lucigen instead of the Warmstart kit from NEB. However, Lucigen has yet to create a colormetric kit for RT-LAMP, and adding phenol-Red (pH...

17 February 2021 5,399 1 View