Top research fronts for 2008

	Topic	Core papers	Citations count	Citations per paper	Mean year
1	Multiple M-2 branes	40	1,196	29.90	2007.8
2	Iron-based superconductors	34	2,089	61.44	2007.7
3	Unparticle physics	40	1,162	29.05	2007.7
4	Induced pluripotent stem cell lines derived from adult somatic cells	29	3,303	113.90	2007.5
5	Type-2 diabetes susceptibility gene	49	4,144	84.57	2007.2
6	Small, or short, RNA pathways	26	1,635	62.88	2007.2
7	Metastable supersymmetry breaking	44	1,307	29.70	2007.2
8	Graphene nanoribbons	24	1,574	65.58	2007.1
9	Breast, colon susceptibility loci	17	1,404	82.59	2007.1
10	Filaggrin mutations and atopic dermatitis, asthma	23	1,199	52.13	2007.0

The table above lists ten “hot” specialty areas, as of the end of 2008, ranked by the average age (mean year) of their foundation literatures (core papers). To focus on large and especially active areas, a threshold of 1,000 citations was employed. These research fronts, as they are called, were derived from a co-citation analysis of highly cited papers for the period 2003-2008, as listed in Thomson Reuters’ Essential Science Indicators database.

In the biological sciences, three fronts represent the advance of research identifying specific genes associated with diseases: type-2 diabetes (in fifth spot), breast and colon cancer (ninth), and atopic dermatitis and asthma (tenth). The generation of pluripotent stem cells from adult fibroblasts has been much in the news (fourth). Less well known is (sixth), focusing on small or short RNA involved in gene silencing. Materials science is represented by two areas: iron-based superconductors, a new class of compounds to add to the more familiar cuprate family (second), and graphene nanoribbons (eighth), which may prove to be an alternative to silicon semiconductors. Three research fronts give a glimpse of frontline work in theoretical physics: multiple M-2 branes (first) and metastable supersymmetry breaking (seventh) are realms of string theory, while unparticle physics (third), introduced by Harvard physicist Howard Georgi in early 2007, hints at a hitherto unknown – and extremely weird – aspect of the standard model.