This site is to serve as my note-book and to effectively communicate with my students and collaborators. Every now and then, a blog may be of interest to other researchers or teachers. Views in this blog are my own. All rights of research results and findings on this blog are reserved. See also http://youtube.com/c/hongqin @hongqin
Monday, February 29, 2016
Wednesday, February 24, 2016
bio125, review 2014 closed book exam. Open book practice.
sec3, 4
go over exercises, practical exam, 2014 closed book
Major problem:
primer on PCR template
Restriction enzymes
oral presentation rubric, learning objectives
Did not have time to go over math problems in section 4.
go over exercises, practical exam, 2014 closed book
Major problem:
primer on PCR template
Restriction enzymes
oral presentation rubric, learning objectives
Did not have time to go over math problems in section 4.
Monday, February 22, 2016
Spelman research day, 2016 spring
The Research Day database is now open. Please use the link below to help students access the registration form and upload their abstract. The abstract deadline is Monday, March 14 at 11:59pm. If you are having trouble opening the form, please copy and paste the link into a different browser.
Please note that research projects do not have to be complete in order to submit an abstract.
Friday, February 19, 2016
bio125 20160219Fri agarose gel of RE PCR fragments
For the lab:
Loading dye on student desks
100bp ladder will be put on instructor's desk, only given to students after they have used the loading dye.
During gel run, go over 2015 midterm open book part.
9am. section 3.
Lab instructor mistakenly gave ladder as loading dye to one group of students, luckily, the student discovered the error.
One group reversed cut-uncut on the gel. One group mistook loading dye as ladder. Both groups blame instructors for interfering their experiments.
Lockdown browser quiz test
Midterm open book test.
1pm, section 4
Most students said that they did not how much volume of 6X loading dye to add to 20ul digestion.
gel run for 45 minutes
2:50pm. the lab ended.
Ref:
http://hongqinlab.blogspot.com/2015/02/bio125-thu-feb-26-2015-student.html
http://hongqinlab.blogspot.com/2015/02/bio125-tue-feb242015-agarose-gel-of-pcr.html
http://hongqinlab.blogspot.com/2015/02/bio125-feb-19-thu-digestion-of-pcr.html
Thursday, February 18, 2016
R xlsx package on Windows7
library(xlsx) cannot be executed because rJava cannot be loaded. Re-installed JAVA, problem persisted.
Install Java SE development kits.
Problem fixed.
Install Java SE development kits.
Problem fixed.
Wednesday, February 17, 2016
bio125 20160217Wed RE of PCR fragments
Before class:
Set 4 water bath/blocks: 60C, 37C, 55C heat block
Water is on their stations. Enzymes are in small -20 in the green ice block on top shelf. Buffers are in 2 boxes on the top shelf labeled buffers for RE enzyme and Restriction enzyme buffer. Each student can get a tube of the buffer that they need. After assembling MMix, the instructor should dispense the enzyme into their master mix for digestion. Water bath are set to 37 and 60. For 55 degree they should use heating block which is turned on and set.
Student samples are in the freezer by the tissue culture hood in the front with section labeled on the box
NEB reformulated their buffers.
Buffer 2.1 = old buffer 2 + BSA
Buffer 2.1 = old buffer 2 + BSA
Section 3:
9:10, go over the lab. I did not put a tutorial video in the right place, and most group did not know which RE to use. I used a student video in class to let the student work on it.
by 10am, most students worked out the solutions.
Section 4
No groups submitted a preclass report that indicated RE needed.
Go over student video on RE identification
Showed student video from morning section.
by 1:41pm, three groups correctly found out RE needed.
by 2:12pm, all groups knew their RE.
2:20pm, all groups start to set up reactions. One group was absent during last lab and did not do PCR. They were asked to finished APE 9 assignment.
Friday, February 12, 2016
bio125 20160212Friday PCR amplification of MSH2
Problem: for video on screen, red does not show on black background.
Section 3:
=>dilute plasmid to 5 ng/uL
9:25am, went over recipe
add large volume of water first. For 200uL pipette, round up the volume to the nearest integers.
Take away concentrated plasmids.
=>PCR master mix.
Go over PCR master mix recipe
9:38am PCR beads are given to students
Problems: One group added master mix into diluted plasmids.
=> try respondus lockdown broswer
=> 30 minutes on PCR paper exercise.
Section 4:
1:30pm, most group submitted wrong plasmid dilution recipe.
by 2pm, at least 3 groups have not started to dilute their pasmid DNA.
by 2:20pm, some groups finished their PCR reactions.
ask a group to finis paper pcr on boards.
========================
skipped:
homework common problems:
Wrong: HNPCC has no symptoms, a google trap.
Correct:
Reference
http://hongqinlab.blogspot.com/2015/02/bio125-thu-pcr-reaction-past-exams.html
http://hongqinlab.blogspot.com/2014/02/bio125-pcr-reaction.html
Section 3:
=>dilute plasmid to 5 ng/uL
9:25am, went over recipe
add large volume of water first. For 200uL pipette, round up the volume to the nearest integers.
Take away concentrated plasmids.
=>PCR master mix.
Go over PCR master mix recipe
9:38am PCR beads are given to students
label both sides of pcr tubes because they can be worn off during PCR.
=> set up reaction.
9:50-Problems: One group added master mix into diluted plasmids.
=> try respondus lockdown broswer
=> 30 minutes on PCR paper exercise.
Section 4:
1:30pm, most group submitted wrong plasmid dilution recipe.
by 2pm, at least 3 groups have not started to dilute their pasmid DNA.
by 2:20pm, some groups finished their PCR reactions.
ask a group to finis paper pcr on boards.
========================
skipped:
homework common problems:
Wrong: HNPCC has no symptoms, a google trap.
Correct:
Reference
http://hongqinlab.blogspot.com/2015/02/bio125-thu-pcr-reaction-past-exams.html
http://hongqinlab.blogspot.com/2014/02/bio125-pcr-reaction.html
Friday, February 5, 2016
bio125 20160205Fri gel electrophoresis, RE compatible ends
Section 3:
9:30 most groups have gel running.
by 9:50am, do RE paper cutting exercise. Most students are chatting, but some students are working on it. Many student do not want to use razor.
During the gel running time, I went over RE enzyme recognition size and its expected number of sites.
Standard curve of gel and plots.
Section 4:
by 1:30, most groups started gel running.
Use paper and RE sites, cut with razor to explain compatible ends.
http://hongqinlab.blogspot.com/2015/02/bio125-thu-feb-5-2015.html
9:30 most groups have gel running.
by 9:50am, do RE paper cutting exercise. Most students are chatting, but some students are working on it. Many student do not want to use razor.
During the gel running time, I went over RE enzyme recognition size and its expected number of sites.
Standard curve of gel and plots.
Section 4:
by 1:30, most groups started gel running.
Use paper and RE sites, cut with razor to explain compatible ends.
http://hongqinlab.blogspot.com/2015/02/bio125-thu-feb-5-2015.html
Thursday, February 4, 2016
write to SEGATE NTFS disk from OSX,
On a OX 10.9.5 mactower system, purchased in 2012
Download Seagate's free NTFS driver
http://www.seagate.com/support/downloads/item/ntfs-driver-for-mac-os-master-dl/
Download Seagate's free NTFS driver
http://www.seagate.com/support/downloads/item/ntfs-driver-for-mac-os-master-dl/
Wednesday, February 3, 2016
bio125, XbaI + ApaI cut pMSH2, pRS413, pmsh2
Before class:
check 37C water-bath or heat block
Xba1 and Apa1 mix
=========
Section 1:
Problems:
Some students did not know that digestion and controls are do in parallel, not sequential.
How to make master mix
Many students have below 100ng/uL plasmid to start with
Some are not sure about diluted plasmid and reaction tubes.
Some students left their eppendorf tubes open all the time.
Do not add water to original plasmid stocks.
Lab instructor removed 10ul pipette because so many of them are broken by the students last year.
9am I started with master mix. This is a mistake. I should start with plasmid DNA dilution steps.
10am. most students are still struggling to the recipe.
10:15am, many finished master mix.
11am. Only one group is still doing the lab.
========
Section 2:
Problems:
What is master mix?
Students mixed up original DNA stocks and diluted DNA working stocks.
1pm, started overview of the lab.
1:10pm, explain plasmid dilution right away.
2:37pm, most groups are working on master mix.
3:15pm, incubation for most groups starts.
References:
http://hongqinlab.blogspot.com/2015/02/bio125-tue-feb-3-2015.html
http://hongqinlab.blogspot.com/2014/02/bio125-xba1-apa1-prs413-pmsh2.html
check 37C water-bath or heat block
Xba1 and Apa1 mix
=========
Section 1:
Problems:
Some students did not know that digestion and controls are do in parallel, not sequential.
How to make master mix
Many students have below 100ng/uL plasmid to start with
Some are not sure about diluted plasmid and reaction tubes.
Some students left their eppendorf tubes open all the time.
Do not add water to original plasmid stocks.
Lab instructor removed 10ul pipette because so many of them are broken by the students last year.
9am I started with master mix. This is a mistake. I should start with plasmid DNA dilution steps.
10am. most students are still struggling to the recipe.
10:15am, many finished master mix.
11am. Only one group is still doing the lab.
========
Section 2:
Problems:
What is master mix?
Students mixed up original DNA stocks and diluted DNA working stocks.
1pm, started overview of the lab.
1:10pm, explain plasmid dilution right away.
2:37pm, most groups are working on master mix.
3:15pm, incubation for most groups starts.
References:
http://hongqinlab.blogspot.com/2015/02/bio125-tue-feb-3-2015.html
http://hongqinlab.blogspot.com/2014/02/bio125-xba1-apa1-prs413-pmsh2.html
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