Human iPSCs (TkDA cell-line) were differentiated on laminin coated plates into endoderm by treatment of Activin and BMP, then treated with FGF4 and CHIR to further differentiate into posterior foregut. The cells were embedded into Matrigel droplets and cultured in Advanced DMEM. Droplet media was collected for ELISA to measure Albumin concentrations. The droplets were collected for histology and RNA isolation to test for AFP, ALB, and HBG1 genes. These methods resulted in the creation of a novel culture system containing both hepatic and hematopoietic lineage cells to model developing fetal liver.
The purpose of this project was to develop a method to characterize polymers using size exclusion chromatography. Specifically, high performance liquid chromatography coupled with a refractive index detector (RID) was used. Polyethylene glycol (PEG) was used a standard for this method. The mobile phase used was dimethylformamide (DMF). Three different mixtures of PEG polymers with known molecular weights were analyzed to characterize the molecular weight of polyacrylic acid (PAA). After running all polymers, retention times were taken and plotted on the x-axis along with LogMp (molecular weight) on the y-axis. A calibration curve was created and plugged in the retention time of PAA to the line equation. We then, took 10 to the power of that number and calculated a molecular weight of 52292.97 g/mol. This method was shown to be an effective way to characterize polymers using PEG as a standard. Poly (methyl methacrylate), otherwise known as P(MMA), was also tested using the same method. The known weight of the polymer was 60,500 g/mol. After running the polymer, 23,000 g/mol was calculated to be the molecular weight. This molecular weight shows that certain parameters like polarity needs to be considered when running samples on the HPLC.
Habitat: beech maple forest, in pine broomsedge area on SW corner of big woods; soil
Locality: Hueston Woods State Park, Hueston Woods Interpretive Area, along S shore of Acton Lake
Habitat: sandstone gorges and ravines with healock/hardwood coves, upland hardwood stands, floodplain, pine stands; soil at base of maple tree
Locality: Crane Hollow Nature Preserve (crane Hollow) S of Gibisonville and N of Conkle's Hollow State Nature Preserve, bordered on the E by OH 374 and W by Cream Ridge Rd.
Habitat: narrow sandstone box canyon with floodplain, upland woods, hemlock/hardwood coves; wet sandstone outcrop
Locality: Conkle's Hollow State Nature Preserve, Big Pine Rd. E of OH 374 between OH 678 and 664 Hocking Hills state Park
Habitat: hardwood swamp/white cedar swamp/ sedge meadow habitat, in sedge meadow; soil, base of cedar
Locality: Cedar Bog State Memorial Nature Preserve, Woodburn Rd. off US 68 ca 2.5mi S of Urbana