Distance and mean citation for middle-middle author relationship in articles with less than 5 coauthors in three resolutions (100 m, 1 km, and 1000 km).

<p>There is no obvious trend.</p

Distance and mean citation for first-last author relationship in three resolutions (100 m, 1 km, and 1000 km).

<p>Distance and mean citation for first-last author relationship in three resolutions (100 m, 1 km, and 1000 km).</p

Scatter plot of distance between authors and citation for high resolution data.

<p>High resolution data is only available for Harvard affiliated authors. Harvard authors are in 4 major geographical locations: Longwood Medical Area, Massachusetts General Hospital (MGH) main campus, MGH Navy Yard campus, and McLean Hospital. Distances between authors are aggregated in discrete values because authors are not uniformly distributed but in one of those 4 locations. Maximum value (12 km) are for authors in MGH campuses and McLean Hospital.</p

Distance and mean citation in different author relationships.

<p>There are four author relationships within an article: first-last, first-middle, last-middle, middle-middle. While there is only one FL in any article, there are (n-2) FMs or LMs in an article with n authors, and (n-2)x(n- 3)/2 MMs. As you can see in FM/LM/MM graphs, the ALL graphs are dominated by > = 5 data because there are way more same relationship pairs as n increases. If there is an article with 100 authors/50 citations, for example, the citation 50 gets counted 98 times in FM/LM mean citation and ∼10000 times in MM. There is one safe case, though. If there are 4 authors, there is only 1 MM. If there are less than 4 authors, there is no MM. Therefore, graphs for FL and MM < = 4 are safe for interpretation. Other graphs should be interpreted carefully.</p

Histogram of data in Figure 2.

<p>Most of the coauthors are very close to each other within 200 m.</p

Mean citation for first-last authors in the same building, same city, or different city.

<p>Scatter plot showing relationship between first author-last author distance and publication citation impact (±2 SEM). Three inter-author distances were selected for illustration: same building, same city or different cities. Results are plotted for publications with four or fewer authors (black), and with five or more authors (red).</p

3-D representation of the relationship between intra-building collaboration and mean citation impact on the Longwood campus of Harvard Medical School.

<p>The height of each building reflects the mean number of citations of publications originating in that building, and the color gradient reflects the proportion of publications originating from that building in which both first and last authors work in the building (from grey = low to blue = high). An interactive version of this map could be found at <a href="http://collaboration.harvard.edu" target="_blank">http://collaboration.harvard.edu</a>.</p

Precursor Patterns for Major Retinal Cell Types

<p>Genes that are selectively expressed in immature subtypes of retinal cells. From the top, the differentiating cell types that express the genes in question are ganglion cells <i>(Mm.45753/KIAA0013),</i> rod photoreceptors <i>(Mm.103742/Cdc42GAP),</i> bipolar cells <i>(Mm.29496/Zf-1),</i> horizontal cells <i>(Mm.2214 /septin 4),</i> amacrine cells <i>(Mm.23916),</i> and Müller glia <i>(Mm.29729/Tweety1).</i> Sections were from central retina. Cellular laminae of both the developing and mature retina are indicated with colored bars. All pictures were taken at 200x. See Table S5 for a full list of probes used.</p

Müller-Glia-Enriched Genes

<div><p>(A) Müller-glia-enriched genes show stronger expression in retinal progenitors than do genes enriched in other postnatally born cell types. See <a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.0020247#s3" target="_blank">Materials and Methods</a> for details of how progenitor-enriched and cell-specific expression patterns were determined, and <i>p</i>-values for progenitor-enrichment of genes that are cell type–specific in the mature retina were calculated. Data on 4N-enriched transcripts were obtained from <a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.0020247#pbio-0020247-Livesey2" target="_blank">Livesey et al. (2004)</a>. Numbers for each value are as follows. For <i>N,</i> the number of cell-enriched genes, <i>N</i>_MG = 86, <i>N</i>_Pr = 112, <i>N</i>_BC = 21, and <i>N</i>_AC = 57. For <i>I,</i> the number of genes that show retinal progenitor-enriched patterns by ISH, <i>I</i>_total = 180, <i>I</i>_MG = 66, <i>I</i>_PR = 15, <i>I</i>_BC = 4, and <i>I</i>_AC = 8. For <i>M,</i> the number of genes enriched in 4N retinal progenitor cells that were tested by ISH in adult retina, <i>M</i>_total = 28, <i>M</i>_MG = 12, <i>M</i>_PR = 3, <i>M</i>_BC = 3, and <i>M</i>_AC = 1. *, <i>p</i> < 10⁻¹³; **, <i>p</i> < 0.0001.</p> <p>(B) Müller-glia-enriched genes show strong expression in mitotic progenitors. The genes shown are: <i>Mm.26062/ADO24, Mm.55143/Dkk3, Mm.5021/DDR1, Mm.35817, Mm.20465/GPCR37, Mm.200608/clusterin,</i> and <i>Mm.22288/cyclin D1</i>. Sections were from central retina. Cellular laminae of both the developing and mature retina are indicated with colored bars. All pictures were taken at 200x. See Table S5 for a full list of probes used.</p> <p>(C) Dynamic expression of metabolic genes in developing retina. Metabolic enzymes are often selectively expressed in mitotic progenitors and developing Müller glia. The genes shown are <i>Mm.27953/glycine decarboxylase, Mm.9114/mu-crystallin,</i> and <i>Mm.213213/HK-R</i>. Cellular laminae of both the developing and mature retina are indicated with colored bars. Sections were from central retina. All pictures were taken at 200x. See <a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.0020247#st005" target="_blank">Table S5</a> for a full list of probes used.</p></div

Genes Expressed in Subsets of Mitotic Progenitors

<div><p>(A) Genes expressed in temporally distinct subsets of progenitors. The first column shows relative SAGE tag levels for each gene under consideration. The UniGene identities and common names of the genes in question are <i>Mm.19155/sFrp2, Mm.3904/Fgf15, Mm.142856/Lhx2, Mm.35829/Edr,</i> and <i>Mm.22288/cyclin D1</i>. The sections for ISH and BrdU shown here were taken from near the center of the retina at the developmental times shown. Mice were albino Swiss Websters except in the case of the adults, which were pigmented C57B/6. See Table S5 for a full list of probes used. Cellular laminae of both the developing and mature retina are indicated with colored bars. All pictures were taken at 200x. The graph plotting the fraction of mitotic cells in the retina adjacent to the BrdU staining is an estimate based on data from both rat and mouse (<a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.0020247#pbio-0020247-Young1" target="_blank">Young 1985</a>a, <a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.0020247#pbio-0020247-Young2" target="_blank">1985</a>b; <a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.0020247#pbio-0020247-Alexiades1" target="_blank">Alexiades and Cepko. 1996</a>).</p> <p>(B) Spatially heterogeneous ONBL. Genes that were expressed in spatial subsets of cells in the prenatal ONBL are shown. The genes shown are <i>Mm.4541/Sox2, Mm.18789/Sox4, Mm.4605/Tbx2, Mm.29067/Mbtd1, Mm.2229/Eya2, Mm.34701/Pum1, Mm.29924/Arl6ip1, Mm.11738/Ark-1, Mm.40321/Pgrmc2,</i> and <i>Mm.22288/cyclin D1</i>. Sections were from central retina. Cellular laminae of both the developing and mature retina are indicated with colored bars. All pictures were taken at 200x. See Table S5 for a full list of probes used.</p></div