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Hello everyone! This is Sebastian with another update on the x-ray machine. This post will discuss the various methods that can be used to determine the radiation dose of our x-ray machine. Below you will find my report on determining x-ray radiation doses.

Evaluating 3 methods for estimating radiation doses
23 March 2012
Sebastian Di Clemente

The population biology lab is trying to determine the dose of x-ray radiation that the x-ray tube emits per x-ray taken. Calculating the radiation dose is not an easy task because there is no straight forward way to do it. Each method used to determine the x-ray dose presents several differences in measure and calculation. Knowing the radiation dose of the x-rays can be used to determine what dose levels will hinder or harm a seed and what dose levels may even be beneficial to seeds; in short, knowing the radiation dose will allow researchers to quantify the point where seeds are affected by the radiation. With this experiment I will evaluate the sources that give the x-ray radiation dose and analyze the information given by each source.

1. To determine what method gives the most accurate information
2. To determine what method should be consulted to find the most appropriate radiation dose

I gathered information based on web searches, contacting professionals, and contacting the x-ray machine manufacturer. I 1.) found a web page that calculates the x-ray radiation dose level and 2.) the manufacture provided the information that they have on dose levels that the Faxitron MX-20 machine produce at various settings. After receiving this information I test the web calculator by inputting the same settings that the manufacture provided and then compared the calculator reading to the value given by the manufacturer. I also further examined the information that the manufacturer provided and determined any differences in information or information format. The use of 3.) a dosimeter would give the most accurate measurement.

After comparing the web calculator result to the information given by the manufacturer using the same settings and criteria there is a significant difference in the dose level given. The web calculator had a dose level that was greater than the valued indicated by the manufacturer for lower level voltages (less than 20 kV), but the manufacturer indicated a greater dose level at anything above 20kV compared to the web calculator. The professionals offer the solution of a dosimeter. The comparison of the manufacturer data to the web calculator, and the three methods are provided in table below.

Comparison between manufacturer data and web calculator:

View image

The web calculator:

The information given by the manufacturer is given in the following documents:

Dosage MX 20.pdf


MX-20 mR Ouput versus time.pdf

The professionals offer the solution of a dosimeter.

Considering all of the information that I gathered I would trust the manufacture data over the web calculator data. The web calculator is good for fast calculations and changing between what units the dose level will be expressed in. Although, after testing the web calculator and see such a significant difference between it's calculation and the manufacturer data, I feel that the manufacture would be more likely to have more accurate information.

Since the manufacture data is most reliable it is the clear choice to use. The manufacturer data covers more information, such as time, voltage, as well as unit conversions for other factors. Considering that more information is provided more variations to experiments can be made and the radiation does would still be available after simple unit conversions.

The other option presented by professionals would be to use a dosimeter to directly measure the radiation dose. This option would be the easiest way out of the three options, and would cater more to a researcher's specific setting. If a dosimeter is available to use I would make this device my choice for determining radiation dose.

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Edited by cswitzer. 25 July 2011

Characteristics of a good CSV file:
1. Use database format in Excel

See this example:
2. Don't mix text, integer, or numeric fields (you may enter NA in a numeric field to signify missing data)
3. Remove spaces from excel cells
4. No punctuation in each column name
5. Don't start a column with a number
6. Column names should be in easily typable format -- use capitals at new words and use no spaces (called camelback format)

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A quick list of flowering plants I noticed while assessing phenology in Jennifer's experimental plot at Hegg Lake WMA on 10 July. I list only plants observed in the plot. Asclepias speciosa is flowering just outside the SE corner of the plot.

F = flowering
X = done flowering/in fruit
N = not yet

Heliopsis helianthoides F
Amorpha canescens N
Coreopsis palmata F
Rosa arkansana F
Anemone cylindrica X
Silene F
Asclepias syriaca F
Amphicarpea bracteata F
Morning glory sp F
Apocyanum F
Tragopogon F
Cirsium arvense F
Lathyrus venosus XF (almost all done flowering)
Galium boreale F
Psoralea argophylla F
Medicago sativa F
Linum sulcatum F
Carduus acanthoides F
Senecio X
Liatris N
Achillea F
Zizea X
Red field clover F
Yellow fl lactucid F
Potentiall arguta F
Desmodium F
Physalis F
Dichanthelium leibergii XF

No Phlox pilosa in the plot!

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InventoryMay2011.doc An inventory of Team E's side of G-3.

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A .csv file with the list of leftover 14000 tags. These tags were not put out in 2009.


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This site explains the circumstances where burning permits are required in Minnesota:

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The string segments that came with the wheeled trimmer were 47 cm long. I used 32 cm sections for trimming rows in the CG.

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Here's a document that outlines a proposed visor form for the census of Caroline's Next Generation Rescue experiment.
Proposed protocol for Next Gen Rescue census 2010.docx

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Here's a list of plants that are available for Katie to use in inb1:
I made this list with this script :plantsForKatieKoch.r

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Hi all,
I have finally figured out how to connect to the printer via the wireless network on a PC. To make sure your computer will be able to access the printer on the network you must do the following:

1) Install the drivers for the LaserJet 2300L. I used the PCL6 driver and it seemed to work fine.
2) Once you have the drivers installed, go to control panel and click on Add Hardware (you must be connected to the wireless network to do this step).
3) When it asks, select that you have already connected the new hardware.
4) Scroll to the very bottom of the next list that appears to where it says "Add a new hardware device."
5) Then select "Install the hardware that I manually select from a list."
6) Select "Printers."
7) Select "Create a new port" and have it be a standard TCP/IP port.
8) Click "next" until it asks you to enter the printers IP address, which is

The application should now be fairly straightforward. At some point you will be asked it you wish to share the printer, select no. You may also print a test copy to make sure that you are connected to the printer.

Let me know if you have questions.

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Here is a copy of my excel file with all my data. The sheet labeled corrected data for analysis is the file with all the data for each treatment. The sheet labeled baggins has a list of all the heads I used that need to be harvested, this was also posted in a separate post called "Baggins." The ones labeled "donor" do not need to be harvested but should not be expected to have high seed set as they were bagged for most of their flowering time.

Pollination interference data (data entry 2).xls


I need all of the heads used in my project (the ones that are painted) to be harvested in egg cartons (located in the shelf above the sink in the Hjelm house). Please label the compartment of the egg carton with the row, pos and tt color of the head. The egg cartons should be packed so that they wont be disturbed during travel and please be careful with the heads so no seeds fall out! Gretel has a list of all the heads to be harvested and its posted on the flog in July ("Baggins"). Please mail the packaged heads to: 119 School Street, Keene, NH 03431


I have been collecting plants at Landfill this season and have started to compile a list of the plants I have either seen or collected there. If Megan and anyone else would like to add plants to that list that would be great! Or check my identification. This list is very rough at the moment but I will continue to update it as I get more plants identified.

Species list landfill 2009.xls

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I wanted to share Diedre and Jake's REU posters with everyone...they both did a great job!
JJF Poster-final.pdf

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We have been very happy using ImageJ to count Echinacea seeds. ImageJ is free, open-source, public domain software. It runs on any platform.

We have also used ImageTool. This program is free and runs on Windows only.

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A list of equipment we need for demo was posted here:

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Where is our study area? We focus on >6400 ha (25 square miles) of land that used to be tallgrass prairie and is now mostly used for agriculture (especially corn & soybeans). There are lakes and sloughs too.

The study area comprises these 25 sections:

T128 N R40 W:
31, 32, 33, 34, 35
T127 N R40 W:
6, 5, 4, 3, 2,
7, 8, 9, 10, 11,
18, 17, 16, 15, 14,
19, 20, 21, 22, 23

Plus, the area extends into the surrounding sections:
T128 N R40 W: 30, 29, 28, 27, 26, 25, 36,
T127 N R40 W: 1, 12, 13, 24, 25, 26, 27, 28, 29, 30,
T127 N R41 W: 25, 24, 13, 12, 1,
T128 N R41 W: 36, 25

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Over the years I have made several notes about locations of Asclepias viridiflora individuals. I have not noted the species at Staffanson Prairie Preserve. I've copied notes below. I can show you where these plants are (on a map or live)...

2-July-1998 site eth
Asclepias vividiflora 6.5 paces S of 2294

1-Aug-1998 site eth
Asclepias viridiflora w pod!

23-July-1998 site nolf
EA pla #3069 cf Asclepias viridiflora 1.1m WSW of this EA

I have mapped an Asclepias viridiflora individual at NRRX. No notes, just the location.

I have collected several seed pods from A. viridiflora at the landfill. Here are the records...
Landfill 9/5/1997 26 seeds 1 pod 4 planted at TP plot
Landfill 9/5/1998 3 pods

Finally, here's a note from my visor from earlier today. The yellow flags are at your prairie turnip plants.

7/3/09 9:31 am
Asclepias viridiflora
2 fl plas between
yel flags 1-02 & 1-28
1 fl pla between
yel flags 1-31 & 1-52
1 fl pla SSE of
yel flag 1-47 (far S) in dip
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Look at this paper to see some nice photos of Echinacea floral parts (Wist and Davis 2008).

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We have several microscopes and we would like to capture digital images of what we see--especially pollen grains. Which on should we pick? Any advice would be appreciated. Here are some links to pages about several models of inexpensive USB cameras that can mount to a microscope: sells several brand. They sell only one line from bigC.

Here's a company that sells the EM series from bigC.

documentation pages on the bigC product line (more on the AM series than the EM series).

Another source of info on the Moticam line.

I scanned this list of companies that sell (and used to sell) microscope accessories to find the above links.

FYI I stumbled across some pollen identification keys: a taxonomic list, a key to pollen of the bahamas, and an inaccessible "pollen database" that sounds good.

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I should introduce myself to the new Team - I'm Ruth Shaw. I've collaborated with Stuart and the Team on this project since 2000. I'm a professor at the University of Minnesota in the Department of Ecology, Evolution and Behavior. Broadly speaking, my research addresses questions about ongoing evolution in plant populations, and I have found this project on the evolutionary consequences of fragmentation of populations of Echinacea endlessly stimulating!
I'm just back from the joint meeting of the Society for the Study of Evolution, The American Society of Naturalists, and the Society of Systematic Biology, where I gave a brief talk about some of our results based on 7-years of data on "Inb1" an experiment to compare the effects of inbreeding and of crossing between remnants. This experiment has been growing in the common garden since 2000, and we have now documented that the degree of inbreeding depression is exceptional, far exceeding that found in other studies. Intriguingly, we have also found that both inbreds and progeny of between remnant crosses harbor more of the specialist aphid than plants derived by random mating within remnants.
A special highlight of the meeting is that our paper about estimating fitness, with examples (available via the main echinacea website), received the President's Award, chosen by the current President of ASN as outstanding paper of 2008 in the journal, The American Naturalist. Quite an honor!
I was out in Douglas County in late May for the early monitoring of seedling recruitment in the remnants, and I'm glad to hear that process is moving forward well! I'm looking forward to getting back out there and working with you all soon!

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Hey team Echinacea,
Lani and Denise officially finished their REU internships last Friday and are both back in the California bay area. They both worked really hard on their projects and ended up with some really neat studies. At the end of their internship they created and presented a poster for a research symposium. Their posters turned out really well and I wanted to share them with you. Below are links to each of their posters...enjoy!
Lani's poster: Download file
Denise's poster: Download file

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Team Echinacea:

A grad student, Emme Bruns, from UMN is studying crown rust. She has been noticing heavy infections of rust on some of the Bromus and Elytrigia (Agropyron) grasses around the twin cities and was wondering if similar infections are occurring up here.

Have you seen anything that looks like a rust pathogen on either of these species?
y5765e1y.jpg ocr.jpg

If the pathogen is present, she would like to visit to survey disease incidence and collect isolates.

Let me know if you see anything like this--and make a mental note or note in your visor where you see it.


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Here's a map (pdf format) of plants in the common garden. A purple asterisk indicates a plant that flowered this year. The size of the asterisk is proportional to the number of heads produced. Download file

We harvested a lot of heads today & yesterday. It's early for us to be harvesting.

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Download file

This is a link to a sample survey sheet that is used for my research. It includes a list of some of the most common plants found in the prairie fragments.


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i started this flog entry last year and never finished it. I'm just going to publish it as it is...

To streamline the process and get everyone on the same page i'm compiling photographs of all the different categories that we are noting in association with Echinacea plants.

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Here's a rundown of our equipment and various settings that we're using.

Sutton Flowform 16
G-kites Dopero
Peter Lynn Pilot 50

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Here are some key resources:

Kensington general forecast and 48-hour surface wind forecast (from NWS in Minneapolis).

Hoffman general forecast and 48-hour surface wind forecast (from NWS in Grand Forks).

Current conditions at nearby weather stations.

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