HYBRID MEMBRANE-PSA SYSTEM FOR SEPARATING OXYGEN FROMAR

A portable, non-cryogenic, oxygen generation system capable of delivering oxygen gas at purities greater than 98% and flow rates of 15 L/min or more is described. The system consists of two major components. The first component is a high efficiency membrane capable of separating argon and a portion of the nitrogen content from air, yielding an oxygen-enriched permeate flow. This is then fed to the second component, a pressure swing adsorption (PSA) unit utilizing a commercially available, but specifically formulated zeolite compound to remove the remainder of the nitrogen from the flow. The system is a unique gas separation system that can operate at ambient temperatures, for producing high purity oxygen for various applications (medical, refining, chemical production, enhanced combustion, fuel cells, etc...) and represents a significant advance compared to current technologies

PREFERENTIAL FLOW EFFECTS ON SUBSURFACE CONTAMINANT TRANSPORT IN ALLUVIAL FLOODPLAINS

For sorbing contaminants, transport from upland areas to surface water systems is typically considered to be due to surface runoff, with negligible input from subsurface transport assumed. However, certain conditions can lead to an environment where subsurface transport to streams may be significant. The Ozark region, including parts of Oklahoma, Arkansas, and Missouri, is one such environment, characterized by cherty, gravelly soils and gravel bed streams. Previous research identified a preferential flow path (PFP) at an Ozark floodplain along the Barren Fork Creek in northeastern Oklahoma and demonstrated that even a sorbing contaminant, i.e., phosphorus, can be transported in significant quantities through the subsurface. The objective of this research was to investigate the connectivity and floodplain-scale impact of subsurface physical heterogeneity (i.e., PFPs) on contaminant transport in alluvial floodplains in the Ozarks. This research also evaluated a hypothesis that alluvial groundwater acts as a transient storage zone, providing a contaminant sink during high stream flow and a contaminant source during stream baseflow. The floodplain and PFP were mapped with two electrical resistivity imaging techniques. Low-resistivity features (i.e., less than 200 Ω-m) corresponded to topographical depressions on the floodplain surface, which were hypothesized to be relict stream channels with fine sediment (i.e., sand, silt, and clay) and gravel deposits. The mapped PFP, approximately 2 m in depth and 5 to 10 m wide, was a buried gravel bar with electrical resistivity in the range of 1000 to 5000 Ω-m. To investigate the PFP, stream, and groundwater dynamics, a constant-head trench test was installed with a conservative tracer (Rhodamine WT) injected into the PFP at approximately 85 mg/L for 1.5 h. Observation wells were installed along the PFP and throughout the floodplain. Water table elevations were recorded real-time using water level loggers, and water samples were collected throughout the experiment. Results of the experiment demonstrated that stream/aquifer interaction was spatially non-uniform due to floodplain-scale heterogeneity. Transport mechanisms included preferential movement of Rhodamine WT along the PFP, infiltration of Rhodamine WT into the alluvial groundwater system, and then transport in the alluvial system as influenced by the floodplain-scale stream/aquifer dynamics. The electrical resistivity data assisted in predicting the movement of the tracer in the direction of the mapped preferential flow pathway. Spatially variable PFPs, even in the coarse gravel subsoils, affected water level gradients and the distribution of tracer into the shallow groundwater system

Impacts of a university philosophy outreach program at Kailua High School

The University of Hawai’i at Mānoa’s Uehiro Academy for Philosophy and Ethics in Education (UHM Uehiro Academy) prepares, supports and sustains philosophy for children Hawai‘i (p4cHI) educators, researchers, and students in Hawai‘i and beyond. This paper documents the impact of the Uehiro Academy’s philosophy outreach program at Kailua High School (KHS), a public secondary school on the Hawaiian Island of O’ahu. It describes the twenty year partnership between the University and KHS, which built a foundation for p4cHI to become integrated across the curriculum and within the school culture. To better understand the overall impact of the UHM Uehiro Academy philosophy outreach program on KHS, researchers asked, ‘How has the UHM Uehiro Academy philosophy outreach program impacted the school culture at KHS?’ Qualitative methods were applied to design and conduct a research study, which included interviewing 68 members of the KHS community. Data analysis revealed four main themes: (1) a schoolwide learner-centred pedagogy, (2) a place for learning more than just academics, (3) a community of diverse and connected individuals, (4) a commitment to professional growth for the purpose of a better world. The paper ends with conclusions, implications of the findings, and the researchers reflecting on the findings, including the benefits and challenges of university philosophy outreach programs in the secondary school setting

Stage-dependent transient storage of phosphorus in alluvial floodplains

Models for contaminant transport in streams commonly idealize transient storage as a well-mixed but immobile system. These transient storage models capture rapid (near-stream) hyporheic storage and transport, but do not account for large-scale, stage-dependent interaction with the alluvial aquifer. The objective of this research was to document transient storage of phosphorus (P) in coarse gravel alluvium potentially influenced by large-scale, stage-dependent preferential flow pathways (PFPs). Long-term monitoring was performed at floodplain sites adjacent to the Barren Fork Creek and Honey Creek in northeastern Oklahoma. Based on results from subsurface electrical resistivity mapping which was correlated to hydraulic conductivity data, observation wells were installed both in higher hydraulic conductivity and lower hydraulic conductivity subsoils. Water levels in the wells were monitored over time, and water samples were obtained from the observation wells and the stream to document P concentrations at multiple times during high flow events. Contour plots indicating direction of flow were developed using water table elevation data. Contour plots of total P concentrations showed the alluvial aquifer acting as a transient storage zone, with P-laden stream water heterogeneously entering the aquifer during the passage of a storm pulse, and subsequently re-entering the stream during baseflow conditions. Some groundwater in the alluvial floodplains had total P concentrations that mirrored the streams’ total P concentrations. A detailed analysis of P forms indicated that particulate P (i.e. P attached to particulates greater than 0·45 μm) was a significant portion of the P transport. This research suggests the need for more controlled studies on stage-dependent transient storage in alluvial systems

Stage-dependent transient storage of phosphorus in alluvial floodplains

Models for contaminant transport in streams commonly idealize transient storage as a well-mixed but immobile system. These transient storage models capture rapid (near-stream) hyporheic storage and transport, but do not account for large-scale, stage-dependent interaction with the alluvial aquifer. The objective of this research was to document transient storage of phosphorus (P) in coarse gravel alluvium potentially influenced by large-scale, stage-dependent preferential flow pathways (PFPs). Long-term monitoring was performed at floodplain sites adjacent to the Barren Fork Creek and Honey Creek in northeastern Oklahoma. Based on results from subsurface electrical resistivity mapping which was correlated to hydraulic conductivity data, observation wells were installed both in higher hydraulic conductivity and lower hydraulic conductivity subsoils. Water levels in the wells were monitored over time, and water samples were obtained from the observation wells and the stream to document P concentrations at multiple times during high flow events. Contour plots indicating direction of flow were developed using water table elevation data. Contour plots of total P concentrations showed the alluvial aquifer acting as a transient storage zone, with P-laden stream water heterogeneously entering the aquifer during the passage of a storm pulse, and subsequently re-entering the stream during baseflow conditions. Some groundwater in the alluvial floodplains had total P concentrations that mirrored the streams’ total P concentrations. A detailed analysis of P forms indicated that particulate P (i.e. P attached to particulates greater than 0·45 μm) was a significant portion of the P transport. This research suggests the need for more controlled studies on stage-dependent transient storage in alluvial systems

Genes regulated by estrogen in breast tumor cells in vitro are similarly regulated in vivo in tumor xenografts and human breast tumors

BACKGROUND: Estrogen plays a central role in breast cancer pathogenesis. Although many studies have characterized the estrogen regulation of genes using in vitro cell culture models by global mRNA expression profiling, it is not clear whether these genes are similarly regulated in vivo or how they might be coordinately expressed in primary human tumors. RESULTS: We generated DNA microarray-based gene expression profiles from three estrogen receptor α (ERα)-positive breast cancer cell lines stimulated by 17β-estradiol (E2) in vitro over a time course, as well as from MCF-7 cells grown as xenografts in ovariectomized athymic nude mice with E2 supplementation and after its withdrawal. When the patterns of genes regulated by E2 in vitro were compared to those obtained from xenografts, we found a remarkable overlap (over 40%) of genes regulated by E2 in both contexts. These patterns were compared to those obtained from published clinical data sets. We show that, as a group, E2-regulated genes from our preclinical models were co-expressed with ERα in a panel of ERα+ breast tumor mRNA profiles, when corrections were made for patient age, as well as with progesterone receptor. Furthermore, the E2-regulated genes were significantly enriched for transcriptional targets of the myc oncogene and were found to be coordinately expressed with Myc in human tumors. CONCLUSION: Our results provide significant validation of a widely used in vitro model of estrogen signaling as being pathologically relevant to breast cancers in vivo

Imprints, [Vol. 5]

This 1989 edition includes winners of the T. E. Ferguson writing Contest, two honorable mentions, and a number of other entries that we felt deserved to be published. I would like to give special thanks to all the judges of the Ferguson Writing Contest who helped make this publication possible, and especially to Dr. Patricia Russell, who one again proved to be an invaluable asset. Her dedication and love for the organization and all it stands for has made this one of the most successful years ever.https://scholarworks.sfasu.edu/imprints/1000/thumbnail.jp