Variable Fluorescence for Cyanobacteria and Prochlorophytes

Researchers interested in quantifying variable fluorescence specifically for cyanobacteria and prochlorophyte communities can now order a RED PhytoFlash.

PhytoFlash is now Available with Analog Output for Easy CTD Integration!

The PhytoFlash is now able to output analog data specifically for CTD integration. Two streams of analog data are available. The yield (Fv/Fm) parameter is automatically provided and users can choose either Fo or Fm as the second parameter.

Laboratory Detection of Histamine in Fish Tissue

The Histamine Module for the Trilogy Laboratory Fluorometer is now available. Users detecting Histamine in seafood, in accordance with the AOAC Official Method 977.13, can now purchase a Histamine Module. A Histamine optical kit is also available for the 10-AU Field Fluorometer.

Learn More About Trilogy

Question:
The equation for determining in-vivo Chlorophyll a is:
chl a (mg Chl a/m^-3)= KF. K is the in-vivo fluorescence sensitivity coefficient (mg Chl a/m^-3/ fluorescent unit). F represents the in vivo fluorescent response.

What are some factors that can affect the K value?

Answer:
1) Species Composition. The K value is species dependent. The ratio of chlorophyll a to plant carbon can be anywhere form 25 to 100%. Differences in cell packaging, chloroplast shape and cell morphology can also result in varying K values.

2) Physical Environmental Parameters. The in vivo fluorescence efficiency of chlorophyll a is dependent on light exposure and temperature. At low light levels, algal cells can optimize the light uptake by pushing chloroplasts to the outer edge of the cell, or by producing more chlorophyll per cell. Both of these responses can result in fluorescence data that falsely represents the algal biomass. Temperature is also a consideration. Fluorescence is indirectly correlated to temperature. As the temperature increases the fluorescence will decrease. This can be corrected through temperature compensation. The temperature coefficient for in vivo chlorophyll a is 1.4%/ °C or .78%/ °F.

3) Physiological state of the cell. The presence of senescent cells (or dying cells) will also affect the K value. There are three outcomes of light energy that is absorbed by chlorophyll a contained in algal cells; 1) it is channeled towards photosynthesis, 2) it is given off as heat, or 3) it is re-emitted as fluorescence. This is why healthier cells fluoresce less than senescent cells.

See our E-support page for a complete description of in vivo chlorophyll a theory, measurement and calibration considerations.

We are excited to announce that the Alliance for Coastal Technologies recently voted Chelsea Donovan, our Environmental Marketing Manager, onto their council of stakeholders. ACT is a
NOAA-funded partnership of research institutions, resource managers, and instrument manufacturers from around the world dedicated to fostering the development of effective and reliable emerging technologies. Chelsea's term will span 2007-2010 and involve participation in meetings focused on emerging technologies as well as upcoming evaluations and workshops.

What?
The Knowledge Database is a robust search engine designed specifically for technical and application questions on Turner Designs instruments. If you have any questions or need assistance in troubleshooting a problem try the Knowledge Database.

How?
You can access the Knowledge Database from our homepage . Click on a specific category and enter a word to begin your search.

Choose from the variety of answers from the search results. Some answers contain documents, pictures, scans or spreadsheets to download.



We encourage your feedback in continually improving our Knowledge Database. If you do not find an answer to your question contact the technical support team. We will make sure your questions are answered and added to the Knowledge Database.

What?
In response for more 'real-world' data from our customers, Turner Designs has launched the TD Databank Program where we present examples of customer research for all instruments and applications. The Databank is organized according to instrument type and application and offers our users real-world examples of how researchers and technicians are using Turner Designs instruments in their work. In addition to providing meaningful information for our customers, by having a description of your work highlighted on our website, it will serve as a means of reaching a greater number of scientists around the globe. We see this as a highly effective means of assisting our users in making informed decisions. In order for this type of program to succeed, we need information from you on your application and how a Turner Designs fluorometer is helping you.

How?
We have designed the TD Databank to make submitting an application summary as easy as possible. The entire process should not take more than 20 minutes. We ask for a brief description of your research, and how you use Turner instruments. Also, a picture or graph of data collected with Turner instruments is requested. To show our appreciation for your databank articles, we will send you a Turner Designs sports bag. Claim your sports bag now by submitting your Databank article!

Why?
We hope you will join us in this exciting and useful program by sharing your knowledge and experience with scientists and technicians around the globe. To take part, please visit http://www.turnerdesigns.com/databank/submit_data.html.