NAME
LIMS for Light Stable Isotopes - Laboratory Information
Management System for Light
Stable Isotopes
ABSTRACT
LIMS for Light Stable Isotopes is a Microsoft Access
database program for managing samples, analyses, reports,
and other data in a stable isotope (and tritium, carbon-14,
and chlorofluorocarbon) laboratory.
The reliability and accuracy of isotopic data can be
improved by utilizing database software to (i) store
information about samples, (ii) store the results of mass
spectrometric isotope-ratio analyses of samples, (iii)
calculate analytical results using standardized algorithms
stored in the database, (iv) normalize stable isotopic data
to international scales using isotopic reference materials,
and (v) generate multi-sheet paper templates for convenient
sample loading of automated mass-spectrometer sample
preparation manifolds. Major benefits of this system
include (i) a dramatic improvement in quality assurance,
(ii) an increase in laboratory efficiency, (iii) reduction
in workload due to the elimination or reduction of the
retyping of data by laboratory personnel, and (iv) a
decrease in errors in data reported to sample submitters.
Such a database provides a complete record of when and how
often laboratory reference materials have been analyzed and
it provides a record of what correction factors have been
used through time. It provides an audit trail for
laboratories.
LIMS for Light Stable Isotopes can store information about
samples and analytical results for the following isotope
ratios, isotopes, and chlorofluorocarbons:
2H/1H 11B/10B 18O/16O 37Cl/35Cl 129Xe/132Xe
3H 13C/12C 21Ne/20Ne 38Ar/36Ar 136Xe/132Xe
3He 14C 22Ne/20Ne 40Ar/36Ar CFC-11
4He 15N/14N 30Si/28Si 83Kr/84Kr CFC-12
7Li/6Li 17O/16O 34S/32S 86Kr/84Kr CFC-113
LIMS for Light Stable Isotopes has proven useful in
laboratories that (i) receive samples for isotopic analysis
from numerous individuals, and (ii) perform at least a few
thousand isotopic analyses per year. Users who do not meet
at least one, and likely both these criteria, will probably
not find worthwhile the investment in time that it takes to
learn and fully apply LIMS for Light Stable Isotopes.
Experience has shown that approximately one week is required
to become reasonably acquainted with LIMS for Light Stable
Isotopes and to set it up for operation in a laboratory.
The user should plan one day for the tutorial in the manual
and three to four days to set up a new database and begin
importing isotopic analyses from mass spectrometers in the
laboratory. Although this may seem like a large investment
in time, the rewards in increased productivity and better
organization in a laboratory far outweigh this setup cost.
Numerous improvements were made for continuous flow isotopic
analysis in versions 7.13 (for Microsoft Access 97) and 8.13
(for Microsoft Access 2000). It is much easier to import
isotopic results from Finnigan ISODAT worksheets, even
worksheets on which corrections for amount of sample
(linearity corrections) have been added. The capability to
determine blank corrections using isotope mass balance from
analyses of elemental analyzer samples has been added. It
is now possible to calculate and apply drift corrections to
isotopic data based on the time of day of analysis. Whereas
Finnigan ISODAT software is confined to using only a single
peak for calculating delta values, LIMS now enables one to
use the mean of two or more reference injections during a
continuous flow analysis to calculate delta values. This is
useful with Finnigan's GasBench II online sample preparation
system. Concentrations of carbon, nitrogen, and sulfur can
be calculated based on one or more isotopic reference
materials analyzed with a group of samples. Both sample
data and isotopic analysis data can now be exported to Excel
files. A calculator for determining the amount of sample
needed for isotopic analysis based on a previous amount of
sample and continuous flow area is now an integral part of
LIMS for Light Stable Isotopes. LIMS for Light Stable
Isotopes can now assign an error code to Finnigan elemental
analyzer analyses in which one of the electrometers has
saturated due to analysis of too much sample material,
giving rise to incorrect isotopic abundances.
METHOD
This database software utilizes Microsoft Access to organize
samples, projects, isotopes, procedures, media, etc. in data
tables. Reports are generated with the Microsoft Access
report generator. Calculations are performed by executing
queries. Data is presented to the user in user-friendly
forms, and can be written to ASCII text files and Microsoft
Excel spreadsheet files.
HISTORY
Two versions of LIMS for Light Stable Isotopes--version 7
for Windows 9x and Windows NT/2000 and Access 97, and
version 8 for Windows 9x and Windows NT/2000 and Access
2000--have been developed concurrently. Version 1 for
Windows 3.x and Access 2 is no longer supported. In the
descriptions of software updates below, the version number
of the Access 97 version is followed by the version number
of the Access 2000 version (or the no-longer-supported
Access 2 version) enclosed in brackets ([]). The first
release of the Access 2000 version (8.13) was made with
version 7.13 of the Access 97 version. The first release of
the Access 97 version (7.01) was made with the release of
version 1.41 of the Access 2 version.
Version 7.13 [8.13] 2000/11/08 - Ability to calculate EA
concentrations added. Right-button mouse capabilities
added. Importing analyses improved by allowing user to
view spreadsheet to be imported. Mass spec spreadsheet
column names for importing moved from configuration form
to Mass Spec form so that column headings for each mass
spec can be unique. Print to file added to several
reports.
Version 7.12 [1.52] 1998/11/12 - Modified code to check date
and time separators in Windows Regional Settings.
Microsoft Access cannot recognize as valid a date and
time such as 9.9.98 11.15.45 where the separator used in
both date and time is a decimal. When this is the case,
LIMS will prompt the user to change one of the separators
before continuing.
Version 7.11 [1.51] 1998/10/26 - Workaround provided for
known Microsoft Access bug that corrupts data. Any code
that uses the bookmark property of a recordset after
records have been deleted is susceptible to the bug.
LIMS now requeries recordsets immediately after deletions
are made.
Version 7.10 [1.50] 1998/09/02 - Enabled storage of dual-
inlet and elemental analyzer results on the same sample.
Version 7.09 [1.49] 1998/06/13 - Added isotopes, isotope-
ratios, and compounds 3H, 3He, 4He, 14C, 21Ne/20Ne,
22Ne/20Ne, 38Ar/36Ar, 40Ar/36Ar, 83Kr/84Kr, 86Kr/84Kr,
129Xe/132Xe, CFC-11, CFC-12, and CFC-113.
Version 7.08 [1.48] 1998/05/10 - Fixed problem in storing
sample delta when Reston-specific features selected.
Version 7.07 [1.47] 1998/04/10 - Added new procedure codes
to indicate sample preparation procedures: 166 (Std Dev,
Low Procedure), 167, 187 (H Conc), 188 (O Conc).
Version 7.06 [1.46] 1998/03/03 - Added new software switches
for modifying how LIMS is configured; added switches to
allow for storage of Finnigan spectrometer elemental
analyzer concentrations (STORE_EA_CONCENTRATIONS),
Finnigan ion gauge values (STORE_ION_GAUGES), and
unexpected procedure codes (STORE_UNEXPECTED_PROCEDURES).
Version 7.05 [1.45] 1998/01/28 - Revised importing of
project data from Microsoft Excel files. Revised
latitude and longitude fields on Sample form.
Version 7.04 [1.44] 1997/12/10 - Revised importing of dates
to correctly handle non-U.S. conventions followed in
specifying dates. Allowed C and N concentrations from
elemental analyzer analyses to be imported and stored.
Version 7.03 [1.43] 1997/11/05 - Fixed errors related to
non-U.S. country settings in Microsoft Windows.
Version 7.02 [1.42] 1997/08/02 - Fixed port number importing
for Reston-specific analyses.
Version 7.01 [1.41] 1997/07/21 - Added peak numbers to
database in order to store continuous flow isotope-ratio
mass spectrometer analyses.
Version 1.33 1996/12/16 - Fixed Delete button on Edit
Samples In Progress form to correctly update sample
information. Added media validation when storing delta
values.
Version 1.32 1996/11/01 - Fixed bug preventing low and high
procedure codes from being saved for two or more samples.
Added low and high procedure code checking. Fixed
problem with date shown in Project form. Fixed problems
with display of hourglass. Replaced semicolons with
commas as delimiters for importing DuPont data. Made
modifications to allow importing of and reporting of
fractional seconds. Modified code to not allow storing
of data when errors encountered in parsing data to be
imported.
Version 1.31 1996/08/30 - Made modification to store sample
headings and isotopic data separately in database rather
than in a single data table.
Version 1.1 1996/02/11 - Early version with basic
functionality.
DATA REQUIREMENTS
Sample and project information can be entered by hand or
imported from Microsoft Excel spreadsheet files. Isotopic
analyses can be entered by hand or imported from files saved
to diskette by Analytical Precision, Europa Scientific,
Finnigan, and Micromass spectrometers, although Micromass
continuous flow analyses files cannot be imported.
OUTPUT OPTIONS
Sample projects with isotopic data can be exported as ASCII
text files or Microsoft Excel spreadsheet files. Numerous
reports can be generated from LIMS.
SYSTEM REQUIREMENTS
To run LIMS for Light Stable Isotopes, the following are
necessary:
- Pentium processor, running at 200 megahertz or faster
- Windows 9x, NT 4.0, or Windows 2000
- up to 17.9 megabytes of free disk space
- 24 megabytes memory
- display resolution of 800x600
- Microsoft Access 97 with Database Drivers and Microsoft
Graph installed, and Microsoft Excel 97; OR Microsoft
Access 2000 and Microsoft Excel 2000
For optimal performance, the following are recommended:
- Pentium processor, running at 450 megahertz or faster
- 64 megabytes memory
- display resolution of 1024x768
DOCUMENTATION
Coplen, T.B., 2000, A guide for the laboratory information
management system (LIMS) for light stable
isotopes--Versions 7 and 8: U.S. Geological Survey Open-
File Report 00-345, 121 p.
CONTACTS
Operational:
U.S. Geological Survey
Tyler Coplen
431 National Center
Reston, VA 20192
tbcoplen@usgs.gov
Distribution:
U.S. Geological Survey
Hydrologic Analysis Software Support Program
437 National Center
Reston, VA 20192
h2osoft@usgs.gov
Official versions of U.S. Geological Survey water-resources
analysis software are available for electronic retrieval via
the World Wide Web (WWW) at:
http://water.usgs.gov/software/
and via anonymous File Transfer Protocol (FTP) from:
water.usgs.gov (path: /pub/software).
The WWW page and anonymous FTP directory from which LIMS for
Light Stable Isotopes software can be retrieved are,
respectively:
http://water.usgs.gov/software/lims.html
--and--
/pub/software/geochemical/lims
See
http://water.usgs.gov/software/ordering_documentation.html
for information on ordering printed copies of USGS
publications.