Critical race theory as a bridge in science training: the California State University, Northridge BUILD PODER program.

BACKGROUND AND PURPOSE: Unconscious bias and explicit forms of discrimination continue to pervade academic institutions. Multicultural and diversity training activities have not been sufficient in making structural and social changes leading to equity, therefore, a new form of critical consciousness is needed to train diverse scientists with new research questions, methods, and perspectives. The purpose of this paper is to describe Building Infrastructure Leading to Diversity (BUILD); Promoting Opportunities for Diversity in Education and Research (PODER), which is an undergraduate biomedical research training program based on transformative framework rooted in Critical Race Theory (CRT). KEY HIGHLIGHTS: By employing a CRT-informed curriculum and training in BUILD PODER, students are empowered not only to gain access but also to thrive in graduate programs and beyond. Poder means "power" or "to be able to" in Spanish. Essentially, we are "building power" using students' strengths and empowering them as learners. The new curriculum helps students understand institutional policies and practices that may prevent them from persisting in higher education, learn to become their own advocates, and successfully confront social barriers and instances of inequities and discrimination. To challenge these barriers and sustain campus changes in support of students, BUILD PODER works toward changing campus culture and research mentoring relationships. By joining with ongoing university structures such as the state university Graduation Initiative, we include CRT tenets into the campus dialogue and stimulate campus-wide discussions around institutional change. Strong ties with five community college partners also enrich BUILD PODER's student body and strengthen mentor diversity. Preliminary evaluation data suggest that BUILD PODER's program has enhanced the racial/ethnic consciousness of the campus community, is effective in encouraging more egalitarian and respectful faculty-student relationships, and is a rigorous program of biomedical research training that supports students as they achieve their goals. IMPLICATIONS: Biomedical research programs may benefit from a reanalysis of the fit between current training programs and student strengths. By incorporating the voices of talented youth, drawing upon their native strengths, we will generate a new science that links biomedical research to community health and social justice, generating progress toward health equity through a promising new generation of scholars.

Detection of geothermal phosphite using high-performance liquid chromatography.

Little is known about the prebiotic mechanisms that initiated the bioavailability of phosphorus, an element essential to life. A better understanding of phosphorus speciation in modern earth environments representative of early earth may help to elucidate the origins of bioavailable phosphorus. This paper presents the first quantitative measurements of phosphite in a pristine geothermal pool representative of early earth. Phosphite and phosphate were initially identified and quantified in geothermal pool and stream samples at Hot Creek Gorge near Mammoth Lakes, California, using suppressed conductivity ion chromatography. Results confirmed the presence of 0.06 +/- 0.02 microM of phosphite and 0.05 +/- 0.01 microM of phosphate in a geothermal pool. In the stream, phosphite concentrations were below detection limit (0.04 microM) and phosphate was measured at 1.06 +/- 0.36 microM. The presence of phosphite in the geothermal pool was confirmed using both chemical oxidation and ion chromatography/mass spectrometry.

Design and development of an automated flow injection instrument for the determination of arsenic species in natural waters.

The design and development of an automated flow injection instrument for the determination of arsenite [As(III)] and arsenate [As(V)] in natural waters is described. The instrument incorporates solenoid activated self-priming micropumps and electronic switching valves for controlling the fluidics of the system and a miniature charge-coupled device spectrometer operating in a graphical programming environment. The limits of detection were found to be 0.79 and 0.98 microM for As(III) and As(V), respectively, with linear range of 1-50 microM. Spiked ultrapure water samples were analyzed and recoveries were found to be 97%-101% for As(III) and 95%-99% for As(V), respectively. Future directions in terms of automation, optimization, and field deployment are discussed.

The development of iodide-based methods for batch and on-line determinations of phosphite in aqueous samples.

Recent developments in the field of microbiology and research on the origin of life have suggested a possible significant role for reduced, inorganic forms of phosphorus (P) such as phosphite [HPO(3)(2-), P(+III)] and hypophosphite [H(2)PO(2)(-), P(+I)] in the biogeochemical cycling of P. New, robust methods are required for the detection of reduced P compounds in order to confirm the importance of these species in the overall cycling of P in the environment. To this end, we have developed new batch and flow injection (FI) methods for the determination of P(+III) in aqueous solutions. The batch method is based on the reaction of P(+III) with a mixed-iodide solution containing tri-iodide (I(3)(-)) and penta-iodide (I(5)(-)). The oxidation of P(+III) consumes free I(3)(-) and I(5)(-) in solution. The remaining I(3)(-) and I(5)(-) subunits are then allowed to react with the amylose content in starch to form a blue complex, which has a lambda(max) of 580 nm. The measurement of this blue complex is directly correlated with the concentration of P(+III). The on-line FI method employs the same reaction between P(+III) and mixed-iodide producing phosphate [P(+V)] that is determined spectrophotometrically by the molybdenum blue method employing ascorbic acid at a lambda(max) of 710 nm. The linear range for both the batch and FI determination of P(+III) was 1.0-50 microM with detection limits of 0.70 and 0.36 microM, respectively. Interference studies for the batch method show that arsenite [As(+III)] and sulfite [S(+IV)] can also be determined by this technique; however, these interferences can be circumvented by oxidizing As(+III) and S(+IV) using KMnO(4) which is an ineffective oxidant for P(+III). Both methods were applied to P(+III) determinations in ultra-pure water and simulated creek water. Results and analytical figures of merit are reported and future work is considered.

Reduced inorganic phosphorus in the natural environment: significance, speciation and determination.

It is commonly assumed that phosphorus occurs almost exclusively in the environment as fully oxidized phosphate (primarily H(2)PO(4)(-) and HPO(4)(2-), where the oxidation state of phosphorus is +V). Recent developments in the field of microbiology and research on the origin of life have suggested a possibly significant role for reduced, inorganic forms of phosphorus in bacterial metabolism and as evolutionary precursors of biological phosphate compounds. Reduced inorganic forms of phosphorus include phosphorus acid (H(3)PO(3), P(+III)), hypophosphorus acid (H(3)PO(2), P(+I)) and various forms of phosphides (P(-III)). Reduced phosphorus has been detected in anaerobic sediments, sewage treatment facilities and in industrial and agricultural processes. Microbiological evidence suggests a significant role for reduced phosphorus species in metabolic processes and raises interesting questions regarding the biogeochemistry of this nutrient in the environment. However, the paucity of data on the presence and cycling of reduced phosphorus compounds in the environment requires attention in order to elucidate the role of these compounds in natural systems. This paper discusses the significance of reduced phosphorus in the natural environment, its speciation and methods of detection.

Detection of hypophosphite, phosphite, and orthophosphate in natural geothermal water by ion chromatography.

Current doctrine states that phosphorus is incorporated into cells in the pentavalent(V) oxidation state as orthophosphate. However, recent studies show that microorganisms contain enzymes used to metabolize reduced forms of phosphorous, including phosphite(III) and hypophosphite(I), which suggests that there is a natural source for these chemical species. This paper will discuss suppressed conductivity ion chromatography methods developed to detect hypophosphite, phosphite, and orthophosphate in a geothermal water matrix containing fluoride, chloride, bromide, nitrate, hydrogen carbonate and sulfate. All peaks were clearly resolved, and calibrations were linear with estimated 3sigma detection limits of 0.83, 0.39, and 0.35 microM for hypophosphite, phosphite, and orthophosphate, respectively.

Long-term studies on the effects of nonvolatile organic compounds on porous media surface areas.

This paper investigates the long-term behavior of porous media contaminated by nonvolatile organic compounds (NVOC) in terms of specific interfacial surface area. Specifically, a natural sand, Moffett sand (MS), was contaminated with naphthalene and the surface area was measured repeatedly over time using nitrogen adsorption-desorption techniques. A field-contaminated sand affected by lamp-black material (LB) from former manufactured gas plant operations was also studied. Lampblack is a carbonaceous skeleton containing polycyclic aromatic hydrocarbons (PAHs) and other hydrocarbons. It is hypothesized that soils contaminated by these types of chemicals will exhibit significantly less surface area than their clean counterparts. The surface areas for the contaminated MS samples increased toward their clean-MS values during the 700-h aging period, but achieved the clean values only after pentane extraction or heating at 60 degrees C. Heating at 50 degrees C failed to achieve a similar recovery of the clean-MS surface area value. Nonspecific mass loss tracked the increase in surface area as indirect evidence that naphthalene loss was the cause of the surface area increase. For the LB samples, aging at 100 degrees C produced a slight decrease in surface area and mass while aging at 250 degrees C caused the surface area to increase roughly threefold while the mass decreased by approximately 1%. These results suggest that, under moderate heating and over the time scale of this investigation, there is a redistribution of the complex contaminant mixture on the solid matrix. Greater temperatures remove mass more efficiently and therefore exhibited the surface area increase expected in this experiment.