Transcript searching the litera..

CHBE Orientation Program
Searching the Literature
1
Background

A literature search in the first step in any research
program



Recall 551 exam
You need to know
 What has been done before
 What techniques have been used
 Who are the leaders
 What are the open questions
All of you are now assigned to research groups


No better time than the present to start your literature search
By April you will need to present a seminar on your research
topic (requires literature search)
2
Objective For Today


Discuss basic strategies for literature searches
Details on Scifinder and web of science,
Engineering Village
3
Effective Literature Searching
Four key steps
 Preparing for the search



Doing the search





Choosing the right initial search terms
Choosing the right databases
Updating the search terms when you see the results returned
by the databases
Be sure to do cited reference searches
Analyzing the results


What information am I looking for?
How can I formulate the question so search engine can answer
it
What should I learn from the papers?
Reporting the results

Previous literature section of the proposal
4
Let me get onto Scifinder to Do
A Search


http://scifinder.cas.org
Need a login: information is at
http://www.library.illinois.edu/chx/sfchan
ges.html
5
Search Engines Are Not People

Search engines use algorithms to find
information




The cannot understand the scientific content or
importance of an article
They can only look for words, phrases, possibly
chemical structures
Most search engines are indexed by index terms and
author supplied titles, keywords, references and
possibly abstracts
You need to formulate your search so the
search engine can find it
6
Examples Of Why Indexing Is
Important
How can I find this
article?
Possible search terms
 Polyelectrolyte
Reference found
brushes
 METAC
 Poly 2-(meth
acryloyloxy) ethyl
trimethyl
Reference
ammonium chloride not found
 The structure of the
polymer
7
Example: Something Masel Worked
On A Few Years Ago


Polyelectrolyte brushes and related structures
as catalyst inks (i.e. polymer supports) for fuel
cells
What search terms do I use to find previous
literature?





Polyelectrolyte brush & fuel cell (no hits)
Polyelectrolyte brush (409 references)
Polyelectrolyte & brush (609 references)
 Several mention nanoparticles
Polyelectrolyte & brush & Nanoparticle (50
references – several on target).
Am I done?
8
At This point I have missed most of the
previous literature




Fuel Cell & Nafion – 3986 references
Fuel cell & acrylic acid 932 references
Fuel cell & styrene sulfonate (300
references)
Am I done?
9
Not done yet!!


Only looked at polyelectrolyte’s
Also need to search other terms

Catalyst inks for fuel cells
10
Key Conclusions

Start with pretty generic search terms
Refine terms to find what you want

Do this several times with different key words




It is too easy to miss things if you only start with one
group of key words
Missing a body of literature guarantees you will not
be funded.
It is better to have more references than fewer
11
I find It Is Important To Prepare For
The Search


Make a list of keywords before you start
Make sure you cover everything on your
list
People tend to stop when they find the
first 20-50 interesting references
 Having a list keeps me going so I can find
the complete literature.

12
So Far Only Key Word Searches- Also
Need To Do Author Searches

Author searches are much more effective than
keyword searches


The search engines do not have to add index terms
I usually find people who are working in an
area and then do author searches



I find that I find many more articles this way instead
of using key word and structure searches
Can save search with your competitors names so you
always get them
This also gives you ideas for key words
13
Cited Reference Searches Much More
Effective Than Key Word Searches
Cited reference searches are searches where you
find papers who cited a key paper


Indexing cited references can be done automatically
since the author has provided the references in a
standard format
 Search engine does not have to manually add key
words
 Not dependent on authors choosing the same key
words as you
Much quicker and more effective than key word
searches
14
Cited Reference Search

Find Papers By Leaders In An Area
Find Who Cites those papers
Repeat for review articles

Example




Masel’s formic acid fuel cell paper from 2002
Kenis work on Laminar Flow reactors
15
Caution Search Engines Miss
Things
Comparison of SciFinder Scholar and Web of Science Coverage,
Whitley, Katherine M. 2002. Analysis of SciFinder Scholar and Web of Science Citation Searches. J
Am Soc Info Technol 53(14): 1210-1215. , doi: 10.1002/asi.10192
Duplication analysis, haphazard sample of U.S. academic chemistry researchers. (The table shows
results for 2-3 researchers in each of seven chemistry subject areas; the chart below shows just the
totals / averages of the seven subjects.)
Total
Citations
Scifinder
Citations
Web of
Science
Cites
Cites in
Cites in WOS
Scifinder but but not
not WOS
Scifinder
3894
3234
2913
981
661
83%
75%
25%
17%
16
Search Engines Of Interest
Scifinder
Beilstein &
Gmellin
Scopus
Engineering
Village
Web Of
Science
Strength
Molecular
structure + text
searches
Information
checked
Most complete
molecule
search tools
Best Search
Tools
Best patent
coverage
Best for
conference
proceedings
Great search
tools
Completeness
Cited
Reference
Search
Coverage
Chem literature
Chem literature Leading
journals
Engineering
literature
All Literature
Completeness
Claims all since
1980, some
before
Most since
1771
Most since
1996 some
older
Many since
1800
Most since
1980
Conference
proceedings
ACS only
No
Many
Many
No
Structure
search
Good
Good
No
No
No
Logical search
(and or not)
minimal
Some
Best
Great
Yes
Cited ref
search
Yes
No
Yes – but
incomplete
no
yes
17
Scifinder Scholar






Software from Chem Abstracts
UIUC has a site license
Available on the web
http://scifinder.cas.org
Need a login: information is at
http://www.library.illinois.edu/chx/sfchan
ges.html
Need Illinois domain to use


Need VPN if you want to use this from home
VPN downloadable from
http://www.cites.uiuc.edu/vpn/index.html
18
Key Limitations Of Scifinder



Librarians/linguists not chemists do most
indexing
Indexing by CAS number not IUPAC structure
Misses articles not published in chemical
journals



Patent coverage spotty
Logical searches particularly weak


e.g. IEEE sensors, MRI imaging
You can and two searches on your computer, but
only after you download them 100 references at a
time
Weird license limitations
19
License Limitations For Scifinder

Download at most 100 references at a
time, 5000 per session


Allowed to only keep 5000 search results
at a time in format written by scifinder


Requires downloads to do logical (And/or)
searching
No limitation on references imported to
endnote or refworks provided search results
deleted from your computer
No commercial/consulting use
20
Examples
Scifinder
 http://scifinder.cas.org
Web Of Science
 http://www.library.uiuc.edu/orr/get.php?instid=
258127
Engineering Village
 http://www.engineeringvillage.com
Scopus
 http://www.scopus.com
Google
21
Summary

You need a good literature review for orals


Random use of search engines usually misses key
literature so you need a strategy



Plan and then execute
Be sure to do author and cited reference searches
Strategy should consider indexing – requires a different
strategy for




Start now
Papers in the last 6 months (usually only cited reference
searches)
Papers since 2001 – usually found in common search engines
by many key words, structures
Papers before 2001 – only key word and cited reference
searches effective.
Cited reference searches are particularly effective since
the indexing terms are provided by the authors in a
consistent way
22