Why is the matrix P positive definite?

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Can we classify HV and LV lines based on line length?

I have dataset which shows the length of power lines. I need to classify the lines based on the line length. Is there a rule to classify the High voltage (HV) and low voltage (LV) lines based on...

03 March 2021 4,116 4 View

Formulate model for one integer optimization?

I am working on one optimization problem. the model with two states, the transition between the two states based on one threshold value (L = 5, which L< 5 -> Normal state, L== 5 ->...

11 February 2021 4,045 3 View

How could I get the P-value from the mean, SEM, and n of different groups in the t-test?

How could I get the P-value from the mean, SEM, and n of different groups in the t-test without the original data? For detail, I would like to know the P-value between BMP-2: 50ng/ml group and the...

06 February 2021 6,539 4 View

Why are my western blot bands so distorted?

Hi guys I'm out of ideas here please help! I've never had consistent problem like this doing westerns before and I can't figure it out. The condition used: - First 4 lanes have 50ug protein in...

04 February 2021 2,297 3 View

The impact of different poisson's ratios when analysising field vibration?

The Poisson's ratio of soil is quite difficult for us geo-engineers to obtain. I came across a problem when I tried to determine the parameters in a FEM model. For the saturated clay in...

02 January 2021 8,971 3 View

What are the possible drawbacks of using miRNA sponge to enhance the specificity of gene expression?

I am searching for miRNA repeats put between WPRE and 3'LTR of my lentivirus, in order to enhance the specificity of transgene expression in human neuron cells. But if clinically translation of...

26 December 2020 9,921 2 View

Can Apparent Activation Energy determine Conversion Rate in a catalysis reaction?

Recently, I got a concept that is contrary to my understanding from two papers. It can be described as follows, in brief: There are two catalysts for the same reaction, on the catalyst with higher...

09 December 2020 2,406 28 View

What is the standard preparation procedures of Powder X-Ray Diffraction (PXRD) sample?

Recently I started to use XRD to study the structure of some molecular sieves. My powder sample was prepared by grinding in a mortar, drying in an oven, and loading on the sample holder. However,...

03 December 2020 7,504 8 View

What does a higher LoD indicate in context of COVID19?

I have seen COVID19 test LoD ranging from 180 to 600000 NAAT Detectable Units/mL So a rapid antigen test with LoD of TCID50 1.13 x10^2 per mL and RT PCR TCID50 1x10^-2 per mL (600 NDU/mL) and a...

28 November 2020 1,238 3 View

Could anyone professional help me to solve this problem?

I have installed the software BRUKER Flexanalysis 3.4 on my computer successfully. But when I tried to import the MS data produced by BRUKER MALDI-TOF-MS, I met with an error described in the...

10 November 2020 8,205 1 View

How to classify strictly upper triangular matrices by similarity?

Let F be a field. Consider U, the set of n times n strictly upper triangular matrices in F. For X, Y in U, we call them similar if there exists some S, which is non-degenerate and upper...

01 March 2021 2,957 8 View

Is CD44 degraded in lysosome together with hyaluronan after CD44 mediated endocytosis of hyaluronic acid?

Also when RHAMM binds hyaluronic acid, they get internalized, will RHAMM also be degraded? Or both CD44 and RHAMM will be transferred back to the cell membrane? Asking for breast cancer cell line...

01 March 2021 8,169 2 View

Why is the sum of the elements in a row in a Q matrix equal to zero?

When explaining substitution models, the substitutions are expressed as Q matrix. Why is the sum of the elements in a row zero?

28 February 2021 3,864 3 View

Distribution of particles in metal matrix?

How would define the "good" and "poor" distribution of particles within the matrix. Is there a quantitative solution to assess the distribution of the particles, which then having denotation of...

28 February 2021 7,397 8 View

How to find a correlation between coordinates in a curvilinear coordinate system?

Hello. I have a skewed elliptical coordinate system (I use alternative elliptical coordinates). And I need to determine connections between coordinates in order to fetch a covariance matrix of...

28 February 2021 364 3 View

For modelling epoxy-based matrices (in composites), which model in ABAQUS is the most suitable, Concrete damaged plasticity or Drucker-Prager model?

I am working on developing a micromechanical FE model for predicting kink-band formation in UD composites. To model matrix plasticity, which model, out of Concrete Damaged Plasticity and...

28 February 2021 5,415 1 View

What are the methods used for CNT..?

Respected Professor's i hope you are doing well and happy. i need some information about carbon Nanotubes. before blending the CNT with the matrix the CNT has been introducing in some treatments....

24 February 2021 5,383 5 View

How can I generate random samples from Bingham distribution in R? How can I construct those symmetric matrices?

in the function rbingham(n,A) in R software how can I construct that A (symmetric) matrix?

24 February 2021 3,528 3 View

How does the injection volume impact LLOQ and ULOQ in regression analysis (LC-MSMS)?

Hello, I have run into an issue that has sparkled a debate at work: is the LLOQ/ULOQ impacted by injection volume under the following circumstances: 1) Same dilution factor of all samples 2)...

23 February 2021 9,159 3 View

Multinomial probabilities and confidence intervals - obtaining the CI of the reference category?

Hi, Some background to my question: I have fitted 1st order multinomial Markov models with covariates. Since all probabiilties (for each row of the transition matrix) sum to 1, I estimate only...

22 February 2021 2,541 4 View