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Sample A: Cover Page of Thesis, Project, or Dissertation Proposal

Sample A: Cover Page of Thesis, Project, or Dissertation Proposal

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platf<strong>or</strong>ms are used to deposit them at their designated spots. The use <strong>of</strong> such cloned inserts <strong>of</strong>fers<br />

investigat<strong>or</strong>s immediate access to reagents and thus ease in modifying chip designs and thereby<br />

flexibility in their research. The investment in the robotics is prohibitively expensive to<br />

individual lab<strong>or</strong>at<strong>or</strong>ies and theref<strong>or</strong>e <strong>of</strong>ten research parks and academic centers start c<strong>or</strong>e<br />

lab<strong>or</strong>at<strong>or</strong>ies to provide these services f<strong>or</strong> their community <strong>of</strong> investigat<strong>or</strong>s [60]. The established<br />

protocols <strong>of</strong> these c<strong>or</strong>e lab<strong>or</strong>at<strong>or</strong>ies present the issue <strong>of</strong> reproducibility <strong>of</strong> cDNA Microarray<br />

experiments, since quality control and lab<strong>or</strong>at<strong>or</strong>y protocol implementations can vary per c<strong>or</strong>e<br />

facility [61]. In general our lab does not analyze cDNA array data due to the lack <strong>of</strong> complete<br />

probe characterization and quality control steps in the manufacturing steps.<br />

Parallel to the development <strong>of</strong> cDNA Microarrays has been the private sect<strong>or</strong>’s development <strong>of</strong><br />

mass-produced, sh<strong>or</strong>t (25-70) oligonucleotide Microarray platf<strong>or</strong>ms [8, 11, 12]. The maj<strong>or</strong><br />

companies producing these Microarrays include: Agilent [12], NimbleGen [11], and Affymetrix<br />

[8]. The latter two use in situ, <strong>or</strong> on the surface, production <strong>of</strong> probes by photolithographic<br />

methods [5, 10, 62]. The computer-chip derived production methods <strong>of</strong> these Microarrays allows<br />

f<strong>or</strong> extremely high density spotting <strong>of</strong> probes, and indeed the spotting density has followed<br />

Mo<strong>or</strong>e’s Law [63]. Where Mo<strong>or</strong>e’s Law has predicted the increase in computational mem<strong>or</strong>y<br />

over time, the increases in mem<strong>or</strong>y are directly prop<strong>or</strong>tional to the spotting density <strong>of</strong> electrical<br />

circuits. The differences in manufacturing designs are in the production approaches. NimbleGen<br />

and Affymetrix both make use <strong>of</strong> UV irradiation <strong>of</strong> reactive subunits at the surface, while Agilent<br />

uses piezo-electric delivery <strong>of</strong> either reactive subunits <strong>or</strong> pre-manufactured and purified<br />

oligonucleotides [8, 11, 12]. There are inherent chemistry limitations to the photolithographic<br />

methods, which limits the probe length to a maximal 25 nucleotides, after which the failure<br />

sequences begin to accumulate [5]. Affymetrix directly builds the probe on the Microarray chip<br />

15

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