A video post on methods! Today Chloe Wooldridge and Juan P. Maestre talking about the SKC Biosampler.
According to wikipedia a bioaerosol "is a suspension of airborne particles that contain living organisms or were released from living organisms". These particles vary in size, from nanometers (viruses), micrometers (bacteria and fungi), to hundred micrometers (pollen particles). Bioaerosols can be collected by means a variety of devices such as collection plates, electrostatic collectors, and impactors.
The SKC Biosampler is an impactor, part of the so-called impinger samplers. These kind of samplers impact bioaerosols into a liquid, such as phosphate buffer solution (PBS), that swirls upward on the sampler's inner wall and collects the particles. According to SKC, the BioSampler is a highly efficient collector and only requires a high-volume sonic flow pump to trap airborne microorganisms.
Here the video on how to use this device.
I hope you like it!
Here for your reference, a couple of papers using this device: 1 and 2.
Dear students, here you have the information about the Relative Humidity and Temperature for indoor and outdoor.
Here the link to download the data:
Here two schemes representing the locations where some of the samples were withdrawn.
Let me know if you have any question. Follow updates on Twitter @UTBiome, and LIKE US on Facebook https://www.facebook.com/UTBiome . 
Thanks Harish Sangireddy for your help with the schemes!
I just want to give you an update regarding the samples we took on Tuesday and the metadata associated. The metadata is being compiled and curated to make sure all data were correctly annotated. The samples have been processed and are kept frozen at -20C. In the next 24 hours some of the samples will be DNA-extracted. Afterwards we will be doing qPCR to estimate total bacterial load in the selected samples. If any of you want to come over the lab and collaborate, please let us know. It will be a pleasure to show you the lab and the procedures.
Follow updates in twitter @UTBiome, in facebook UTBiome and here.
JP.
Today the students from CE369L have been sampling in class (oh well, we started by 7am). The 11 groups of students were sampling not only in the actual classroom but also in the corridor, the adjacent hall and outside. Bioaerosol samples were taken indoor and outdoor by using SKC impingers and Button Samplers. A baseline was established before the students came in and the "in class" measurements started as early as 8am. Sleepy faces could be observed around 
.
Dust had been collected in plates for 5 days. A variety of surfaces were wiped and swabbed too. The biological samples were complemented with #metadata: CO2, particle counts, surface temperatures, relative humidity and temperature, air flowrates (for the whole class and on the sample locations) and pressure differences (between class and corridor). Here some pictures of the sampling event.
It was very fun and instructive. A great experience!
CE369L students,
It is about time to start your projects! Last week @yeipijotape (JP), Alex, marwa and Dr. Kinney gave you an introduction to the sampling we will be doing during class. The objective of this post is to make a brief summary of what we will be doing. We will have 11 groups of students and the idea is that all of you will be taking #metatada measurements along with biological samples.
Regarding the biological samples, you will be taking samples with: swabs, wipes, plates (already located in the classroom), a "Button" sampler, and an impinger. The samples not only will be taken inside the class but also on the corridor and outside.
As #metadata we will be measuring: #CO2, Relative Humidity and Temperature, surface temperature (for those samples involving surfaces), air velocity, particle counts by size and location coordinates (special coordinates system to specifically locate the samples in the building).
I will be preparing your sample kits and structuring your sample sites. There will be some hypotheses behind the sample locations selections (some of you already suggested some in class). Feeling the fun already? It will be fun!
Get ready your smartphones to scan the codes and start typing your data.
Hi CE341 students,
Today is Nitrate measurement day. Nitrate is the most completely oxidized form of nitrogen. It is formed during the final stages of biological decomposition, either in wastewater treatment facilities or in natural water supplies. Low-level nitrate concentrations may be present in natural waters. However, a Maximum Contaminant Level of 10 ppm nitrate-nitrogen has been established for drinking water by the USEPA. Fernando Almada and I have made a video for explaining how to measure it by using the Chemetrics handheld spec and the cadmium reduction method:
Nitrate is reduced to nitrite using cadmium as the reducing agent. The resulting nitrite concentration is then determined colorimetrically. This method is applicable to drinking and surface waters, as well as domestic and industrial wastes. Results are expressed as ppm (mg/L) NO3-N or NO3. (Note that if there is any pre-existing nitrite, this will be count as nitrate too)
References: ASTM D 3867-09, Nitrate-Nitrite in Water, Test Method B. APHA Standard Methods, 21st ed., Method 4500-NO3- E (2005). USEPA Methods for Chemical Analysis of Water and Wastes, Method 353.3 (1983). www.chemetrics.com
Click here to see the video in youtube.
PS: the video may take few seconds to charge. Please, be patient. You can click on it if it does not autoplay
Hello everyone,
Dr. Maria Gloria Dominguez-Bello will be giving a seminar as described below at the Avaya Auditorium in the ACES building on Tuesday, November 12 at 3:00.
Please feel free invite anyone who might be interested.
"Microbes across cultures"
'Microbes are everywhere, including those that coevolved in and on us and play important physiological roles. The best known microbes are from Westernized peoples. We have evidence of changes in the human microbiome, with reduced microbial diversity as Westernization increases. However, we do not know how microbes from the body and the built environment change with Westernization.
We are studying microbes of villages across a transculturation gradient in the Amazon basin. We sampled microbes from 10 homes in each of 4 villages across the gradient, including 150 subjects, 34 animals and 496 objects. We also measured home environmental parameters, and preliminary results indicate changes in the use of home space and architecture, leading to changes in ventilation, temperature variation, UV, and of building materials that can be relevant to home microbes.'
Maria Gloria Dominguez-Bello, PhD
Associate Professor
Human Microbiome Program
Division of Transnational Medicine
New York University School of Medicine
http://www.med.nyu.edu/biosketch/dominm05
Hi young researchers! My name is Felipe Gutierrez. I am grad student in Dr.Kinney's lab. Today we are going to measure total orthophosphate from the samples collected in Waller Creek.
We used the Ascorbic Acid method described in “Standard Methods for the Examination of Water and Wastewater.”
We pipetted 4 ml aliquots from each sample and placed them in phosphorus-free glass reaction bottles. Then, we add a drop (~1 µl) of phenolphthalein to check if the sample is not too alkaline for the reaction. Since none of the samples turned pink we continued with our procedure.
Then, we proceeded to add .64ml of a solution composed of 5N sulfuric acid, potassium antimonyl tartrate, ammonium molybdate and 0.1 M ascorbic acid. After the solution is added we wait for 10 minutes. During these 10 minutes the potassium atimonyl and ammonium molybdate react with the orthophosphate to form a complex that shines blue in the presence of ascorbic acid. The intensity of the color blue is proportional to the concentration of orthophosphate in the sample.
Finally, we transferred about 3 ml from the reaction bottle into a glass 1cm-width cell and we measured light absorbance at 880 nm in the spectrometer. With the value of absorbance we can calculate the concentration of orthophosphate in each sample.
Do you want more details? Ask us here (post a comment), in facebook (facebook/UTBiome) or in Twitter (@utbiome).
