Different letters indicate statistically significant differences between groups

Different letters indicate statistically significant differences between groups

Recently I stumbled upon a paper that used different letters to show statistical significances between groups. Aka different significance levels were denoted with different letters (a, b, c). The meaning behind the letters is likely immediately apparent to a more seasoned researcher, though it was not obvious to me at first. For variables with the same letter, the difference is not statistically significant. Likewise, for variables with a different letter, the difference is statistically significant. In the figure below, taken…

Read More Read More

Speculations on the function of NPC1L1 in the liver

Speculations on the function of NPC1L1 in the liver

In an excellent review written by Lin Jia et al (10.1146/annurev-physiol-012110-142233), the authors discuss aspects about the functionality of the Niemann-Pick C1-Like 1 (NPC1L1) Protein in the intestine. In the intestinal epithelium, NPC1L1 functions as an all-round sterol uptake protein. Given that Vitamin K1 and K2, as well as cholesterol and plant sterols are taken up by NPC1L1, whereas vitamin K3 is likely not taken up by NPC1L1, I personally hypothesize that the recognition site of NPC1L1 (whereby it recognizes the…


Polynomial regression in Excel using LINEST


Similarly to linear regression, there is often a need to calculate 2nd or 3rd degree polynomials. The data below is the theoretical frequency distribution of unlabeled cholesterol (y) with varying amounts of labeled acetate (x, the precursor pool). In mammalian biology, acetate is used to produce (among other metabolites) cholesterol in a biochemical pathway consisting of numerous intermediates. Empirically it was calculated that cholesterol appears as a polymer of 12 acetate molecules (chemically this is not the case). The relative…

Read More Read More

Linear regression in Excel using LINEST


You’re likely all too familiar with calculating linear regression using Microsoft Excel. By plotting the data on a X-Y plot, we are able to visualize the data and also to calculate the slope, Y-intercept and the correlation coefficient. If we have a lot of data, we can automate the process by using the following formula: Slope, m: =SLOPE(known_y, known_x) y-intercept, b: =INTERCEPT(known_y, known_x) Correlation Coefficient, r: =CORREL(known_y, known_x) R-squared, r2: =RSQ(known_y, known_x) The Basics: obtaining the m and b value without…


Merging fluorescent microscopy photos together to visualize & analyze a full tissue section

(678) 770-8378

Recently I’ve done some work with our lab’s Zeiss LSM 700 fluorescent microscope and I ran into an issue that seemed easily solvable. The issue was that our microscope’s stage does not have a motorized stage control in the X nor the Y direction. That is, moving the sample horizontally without making an adjustment to the distance between the subject and the lens. It does, however have motorized control for the Z direction (the distance between the object and the…


Raven’s Jig – Enfants Atomiques


In my free time, I play the instrumentals for a musical duo called ‘Raven’s Jig’. With the two of us, we take existing songs and arrange them into new ones. Occasionally we play songs from a Japanese game series called Touhou Project. The reasons for picking this particular source vary from melodic quality and going all the way to its popularity on the net. At the end of the day, the main reason why we arrange songs from this particular…


Is a password a form of ‘security through obscurity’?


Imagine that, despite the lock on your front door keeping your possessions safe, your garage door’s lock has been broken for a while. Your house is wide and open! Why don’t you come on in? You reason that the obscurity of the status of your garage door is sufficient in keeping your possessions (the system) safe. I mean, who’s gonna check that, right? Is this reasoning fair? We’re dealing with ‘security through obscurity’ here. A long story short; securing a system by…