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This data set reports stream temperature, specific conductance, pH, dissolved oxygen percent saturation, dissolved oxygen concentration, turbidity, and fluorescent dissolved organic matter for East Fork Poplar Creek at a location approximately 5.4 kilometers upstream from the mouth of the creek.
This data set reports stream temperature, specific conductance, pH, dissolved oxygen percent saturation, dissolved oxygen concentration, turbidity, and fluorescent dissolved organic matter for East Fork Poplar Creek at a location approximately 5.4 kilometers
This data set reports stream temperature, specific conductance, pH, dissolved oxygen percent saturation, dissolved oxygen concentration, turbidity, and fluorescent dissolved organic matter for East Fork Poplar Creek at a location approximately 5.4 kilometers
This data set reports stream temperature, specific conductance, pH, dissolved oxygen percent saturation, dissolved oxygen concentration, turbidity, and fluorescent dissolved organic matter for East Fork Poplar Creek at a location approximately 5.4 kilometers
This data set reports stream temperature, specific conductance, pH, dissolved oxygen percent saturation, dissolved oxygen concentration, and turbidity for East Fork Poplar Creek at a location approximately 16.2 kilometers upstream from the mouth of the creek.
This data set reports stream temperature, specific conductance, pH, dissolved oxygen percent saturation, dissolved oxygen concentration, and turbidity for East Fork Poplar Creek at a location approximately 16.2 kilometers upstream from the mouth of the creek.
This data set reports stream temperature, specific conductance, pH, dissolved oxygen percent saturation, dissolved oxygen concentration, and turbidity for East Fork Poplar Creek at a location approximately 16.2 kilometers upstream from the mouth of the creek.
This data set reports stream temperature, specific conductance, pH, dissolved oxygen percent saturation, dissolved oxygen concentration, and turbidity for East Fork Poplar Creek at a location approximately 16.2 kilometers upstream from the mouth of the creek.
This data set reports stream water temperature, specific conductance, pH, dissolved oxygen percent saturation, dissolved oxygen concentration, and turbidity for East Fork Poplar Creek at a location approximately 5.4 kilometers upstream from the mouth of the creek.
This data set reports stream water temperature, specific conductance, pH, dissolved oxygen percent saturation, dissolved oxygen concentration, and turbidity for East Fork Poplar Creek at a location approximately 16.2 kilometers upstream from the mouth of the creek.
This data set reports stream water temperature, specific conductance, pH, dissolved oxygen percent saturation, dissolved oxygen concentration, and turbidity for East Fork Poplar Creek at a location approximately 5.4 kilometers upstream from the mouth of the creek.
This data set reports stream water temperature, specific conductance, pH, dissolved oxygen percent saturation, dissolved oxygen concentration, and turbidity for East Fork Poplar Creek at a location approximately 5.4 kilometers upstream from the mouth of the creek.
This data set reports stream temperature, specific conductance, pH, dissolved oxygen percent saturation, and dissolved oxygen concentration for East Fork Poplar Creek at a location approximately 5.4 kilometers upstream from the mouth of the creek.
This data set reports stream temperature, specific conductance, pH, dissolved oxygen percent saturation, and dissolved oxygen concentration for East Fork Poplar Creek at a location approximately 5.4 kilometers upstream from the mouth of the creek.
This data set reports stream temperature, specific conductance, pH, dissolved oxygen percent saturation, and dissolved oxygen concentration for East Fork Poplar Creek at a location approximately 5.4 kilometers upstream from the mouth of the creek.
This data set reports stream water temperature, specific conductance, pH, dissolved oxygen percent saturation and dissolved oxygen concentration for East Fork Poplar Creek at a location approximately 5.4 kilometers upstream from the mouth of the creek.
This data set reports stream water temperature, specific conductance, pH, turbidity, dissolved oxygen percent saturation and dissolved oxygen concentration for East Fork Poplar Creek at a location approximately 16.2 kilometers upstream from the mouth of the creek.
Purpose: Photoacoustic computed tomographic spectroscopy (PCT-S) provides intra-tumor measurements of oxygenation with high spatial resolution (0.2mm) and temporal fidelity (1–2 minutes) without the need for exogenous agents or ionizing radiation, thus providing a unique in vivo assay to measure SaO{sub 2} and investigate acute and chronic forms of hypoxia. The goal of this study is to validate in vivo SaO{sub 2} levels within tail artery of mice and the relationship between SaO{sub 2} and pO{sub 2} within subcutaneous breast tumors using PCT-S imaging, pulse oximetry and an OxyLite probe. Methods: A closed circuit phantom was fabricated to control blood oxygenation levels, where SaO{sub 2} was measured using a co-oximeter and pO{sub 2} using an Oxylite probe. Next, SaO{sub 2} levels within the tail arteries of mice (n=3) were measured using PCT-S and pulse oximetry while breathing high-to-low oxygen levels (6-cycles). Finally, PCT-S was used to measure SaO{sub 2} levels in MCF-7, MCF-7-VEGF165, and MDA-MB-231 xenograft breast tumors and compared to Oxylite pO{sub 2} levels values. Results: SaO{sub 2} and pO{sub 2} data obtained from the calibration phantom was fit to Hill’s equation: aO{sub 2} levels between 88 and 52% demonstrated a linear relationship (r2=0.96) and a 3.2% uncertainty between PCT-S values relative to pulse oximetry. Scatter plots of localized PCT-S measured SaO2 and Oxylite pO{sub 2} levels in MCF-7/MCF-7-VEGF165 and MDA-MD-231 breast tumors were fit to Hill’s equation: P50=17.2 and 20.7mmHg, and n=1.76 and 1.63. These results are consistent with sigmoidal form of Hill’s equation, where the lower P{sub 50} value is indicative of an acidic tumor microenvironment. Conclusion: The results demonstrate photoacoustic imaging can be used to measure SaO{sub 2} cycling and intra-tumor oxygenation, and provides a powerful in vivo assay to investigate the role of hypoxia in radiation, anti-angiogenic, and immunotherapies.