Antioxidant enzyme response in rainbow trout (Oncorhynchus mykiss) after subchronic exposure to an environmentally-relevant polycyclic aromatic hydrocarbon mixture

Polycyclic aromatic hydrocarbons (PAHs) are significant pollutants in aquatic environments. Many are carcinogenic and lead to DNA fragmentation and adduct formation in marine and freshwater organisms. Previous research demonstrates that rainbow trout (Oncorhynchus mykiss) compensate to long-term PAH dietary exposures and reduce the DNA damage. The aim of this study was to assess whether upregulation of detoxifying/antioxidant enzymes in rainbow trout at least partially explains compensation to PAH exposure that allows for this reduction in DNA damage. Rainbow trout were fed a diet that contained a mixture of nine high molecular weight PAHs in environmentally relevant ratios and concentrations. Two doses were used: a lower dose of 20 parts per million (ppm) and a higher dose of 200 ppm. Two other treatment formulations were also used containing 20 ppm and 200 ppm concentrations of benzo(α)pyrene. A control group of rainbow trout was also used. 80 rainbow trout per PAH treatment and control were used in this experiment. The fish were fed PAH treatment diets or a control diet daily beginning when their average weight was 20 g. At days 7, 14, 28 and 42 enough fish were sacrificed from each of the four treatment groups plus control to obtain four 1 g pooled liver samples. Body and liver weights were recorded for each sacrificed fish. Various biomarkers and detoxifying/antioxidant enzyme activities were measured. Lipid peroxidation was estimated for all sample groups using a thiobarbituric acidreactive substances (TBARS) assay. NAD(P)H:quinone oxidoreductase 1 [DTdiaphorase], also known as quinone reductase (QR), activities were determined for all sample groups using a modified photometric assay that defines QR levels as the dicoumarol-inhibitable reduction of 2,6-dichlorophenolindophenol (DCPIP). Glutathione peroxidase (GPOX) activities were determined for all sample groups using a modified photometric assay that defines GPOX levels as the reduction of NADPH in cytosolic liver fractions. Catalase (CAT) activities were determined for all sample groups using an assay kit that utilized the reaction CAT has with methanol in the presence of hydrogen peroxide. CAT showed the strongest significant (P < 0.05) response, rising and falling over the time-course of the study in a dose-dependent sinusoidal decay pattern as the system moved toward optimal steady-state activity. GPOX activities increased significantly (P < 0.05) over the time-course of treatments, also showing a sinusoidal decay pattern similar to that seen with CAT, although the GPOX activity followed a slower decay pattern than CAT and was not dose-dependent. QR activities were low overall. This indicated that this detoxifying enzyme was not a major component of the trout’s adaptive response. The TBARS assay was determined to be an insensitive assay for fish tissues due to the harshness and unspecific nature of the test. The mass-spectroscopy-based F2-isoprostanes assay was determined to be a much more appropriate assay for the determination of lipid peroxide levels in fish tissues, based on previous research

DFT+U studies including spin-orbit coupling - a case study for f-electrons in praseodymium-doped ceria

The mixed ionic electronic conductor Ceria exhibits not only a high concentration of Anti-Frenkel defects with high mobility, resulting in ionic conductivity of oxygen ions, but also enables an additional electronic conduction mechanism in form of small polaron hopping between the f-states of the cations. This promotes the reversible exchange of oxygen with the surrounding atmosphere and thus the oxygen storage capacity of the binary oxide CeO2-δ. The material has been established as a model system to describe both ionic and electronic transport processes in bulk material to gain deeper insights into the characteristics of polaron hopping and defect-defect interactions in mixed conductors. By introducing the redox active lanthanide Praseodymium to the Ceria host lattice, both electronic and ionic conductivities are increased in temperature and oxygen partial pressure regions where pure Ceria lacks of good performance. The redox properties of Pr-ions, shifting the equilibrium from Pr4+ to Pr3+ and forming oxygen vacancies, is key to understand the additional contribution to the total electrical conductivity and the enhanced catalytic activity. So far in literature, only the effect of Pr3+-ions in the Ceria host lattice has been investigated by means of density functional theory. To complement these investigations with the impact of Pr-ions in both oxidation states, density functional theory was applied, including a Hubbard-U correction for electronic correlation in the f-states of both cations in Ce1-xPrxO2-δ. A systematic study of spin polarization, antiferromagnetic coupling and spin-orbit interaction of the unpaired 4f-electrons was performed to investigate the influence of magnetic interactions on the description of localized polarons. The preferred localization of the excess electrons on Pr- rather than Ce-ions as well as the defect formation and configuration is discussed by analyzing the resulting energy levels and densities of states of the investigated ideal and defective super cells

Chapter 4- Human Dimensions of Water for Food Production

Feeding 9 Billion and Maintaining the Planet: Meeting the Challenge of 2050 Environmental concerns, which fall outside normal market powers, require special incentives and consideration in water resource decisions, Marty Matlock said. Given that the world’s population now consumes past the point of sustainability, should sustainability be a market choice for consumers? “This should be pre-competitive,” Matlock said. “The consumers should have confidence that everything they buy complies with a certain threshold of humanity, of behavior, of ethics and sustainability.” The market has the power to move materials, goods and services from areas of plenty to those of scarcity. The problem is that the market is not responding to water scarcity, in part because crops are grown where there is no water. For example, in Brazil, areas that once were rainforest now grow 2.4 crops annually for export to China. “They’re exporting de facto water to China,” Matlock said. Another example stems from the 1 billion people who lack access to water and the 2.4 billion who don’t have basic sanitation. Every day, waterborne diseases kill 5,400 children. “That’s the cost of this failure of technology – failure of civilizations,” Matlock said. “It’s a pretty dramatic cost.” Global climate change will increase water scarcity in already water-stressed areas. Although agriculture no longer accounts for 90 percent of global water use, as it did in 1900, agricultural water use has increased fivefold since then. Competing with other sectors for limited water affects the many other uses that are not monetized, such as biodiversity. The Colorado and Ganges rivers offer examples of dramatic decreases in water discharge due to overallocation. Peak flows have not changed, but critical base flows have dropped considerably over time. “It’s hard to have a functional, viable aquatic ecosystem without the aquatic,” Matlock said. Rice, which accounts for 15 percent of human water use, presents another problem. But improvement is possible, Matlock said. Human Dimensions of Water for Food Production Anheuser-Busch InBev, for example, achieved 4.7 percent per-unit reductions in rice culture, saving 3.5 billion liters of water in five years. Water intake is only one issue; equally important is water effluent. From an ecological standpoint, given grossly limited incentive funding, Matlock believes profitable production practices should not be incentivized. “If you already have an incentive for conserving water − reducing soil erosion − then we don’t need to give you more money to do that which you ought to be doing anyway, because the marketplace will weed you out if you don’t perform,” he said. “It’s the things that we don’t incentivize, like preservation of riparian zones, that we should perhaps be incentivizing with our limited resources.” The Mesoamerican Barrier Reef System offers an example of the interconnectedness of agriculture effluent and environmental harm. Pollutants, particularly sediment and nutrients carried downstream from plantations to the Caribbean Sea, have the equivalent effect of a 10-degree temperature change, bleaching the coral reefs. Impacts that are acceptable with 6.7 billion people will not be with 9 billion, Matlock concluded. If management happens only to things that are measured, and not everything can be measured, which metrics are important and how can they be incentivized? “We have to shift our thinking from maximizing any one variable or metric to optimizing several key ones.

Chapter 6- A View from Agricultural Producers

Rainfed and Irrigated Production in Argentina Martin Pasman, an Argentine agronomist with a master’s degree in business administration, began his career as a consultant to farmers and has experience in Argentina, Uruguay, Paraguay and Brazil, where he was instrumental in helping to develop 80,000 hectares in the western part of the Cerrado area. His farming experience stems from his family’s farms, located in five areas of Argentina. Most are rainfed, but one area receives less than 500 millimeters of rain annually. Pasman also runs an irrigation business serving 80 percent of the Argentine market, giving him vast experience in developing irrigated land. Argentina is the second-largest South American country after Brazil and is one-third the size of the U.S. One-third of Argentina receives more than 800 millimeters of rain and depends upon rainfed agriculture, while the majority receives less than 800 millimeters. Argentina cultivates 30 million hectares per year, of which 2.2 million are irrigated. Total production output is 90 million metric tons, and about 70 percent of farmers in Argentina practice no-till agriculture. Pasman’s family came to Argentina from the U.S. around 1825, when it was primarily cattle country. His family brought the first Aberdeen Angus bull to Argentina and also helped develop agriculture. In the 1970s, the family farmed 6,000 hectares, of which only 500 were used for crops, yielding 3.5 tons of corn per hectare and 1.5 tons of wheat per hectare. They plowed the land and used few herbicides and no fertilizers. The majority of the land was used to raise 3,000 head of cattle, which were finished in natural pastures. Today, the family’s farm operation has expanded to 20,000 hectares, 15,000 of them used for agriculture. In the low-productivity land, they also manage 9,000 head of cattle in cow-calf operations, finishing the animals in American style feedlots. In rainfed fields, the Pasmans produce 8 tons of corn per hectare and 3 tons of wheat; under irrigation, they get 12 tons of corn and 6 tons of wheat. The most important crop, however, is soybeans. They also grow potatoes, corn and sunflower seeds for Monsanto Company. The farm uses 42 pivots to irrigate 4,000 hectares, and about 80 percent of the farm is double-cropped: wheat plus soybeans, seed corn plus soybeans, potato plus corn. Argentina uses a huge amount of herbicides and genetically modified crops, Pasman said, adding that his farm was one of the first to produce Roundup Ready® soybean seeds in 1994. A View from Agricultural Producers “The cornerstone of our production technology is no-till,” Pasman said, a technique used on the entire farm except the potato fields, which follow a rotation of one year of potatoes followed by three years of no-till. A corn crop follows the potato harvest in the same year. No-till improves water infiltration and water retention and reduces evaporation because the previous crops’ residue minimizes runoff and allows the soil to retain more water. No-till also reduces erosion risk and increases organic matter, improving oxidation and carbon circulation in the soil. It improves soil fertility, increases productivity and sustainability, and allows farming in difficult soils, particularly shallow soils of 3 inches. No-till uses less than half the water and less labor compared to conventional tillage, reducing production costs by 30 percent, Pasman concluded. “It is very important, the mix of no tillage with center pivot (irrigation) against traditional management.

Appendix- Water for Food conference proceedings

Poster Competition, Conference Participants, and Photos Technologies and Advances in Water Management Human Dimensions of Water for Food Production Genetics and Physiology of Crop Water Other Conference Participants (148-153) Photos (154-160

Chapter 4- Human Dimensions of Water for Food Production

Feeding 9 Billion and Maintaining the Planet: Meeting the Challenge of 2050 Environmental concerns, which fall outside normal market powers, require special incentives and consideration in water resource decisions, Marty Matlock said. Given that the world’s population now consumes past the point of sustainability, should sustainability be a market choice for consumers? “This should be pre-competitive,” Matlock said. “The consumers should have confidence that everything they buy complies with a certain threshold of humanity, of behavior, of ethics and sustainability.” The market has the power to move materials, goods and services from areas of plenty to those of scarcity. The problem is that the market is not responding to water scarcity, in part because crops are grown where there is no water. For example, in Brazil, areas that once were rainforest now grow 2.4 crops annually for export to China. “They’re exporting de facto water to China,” Matlock said. Another example stems from the 1 billion people who lack access to water and the 2.4 billion who don’t have basic sanitation. Every day, waterborne diseases kill 5,400 children. “That’s the cost of this failure of technology – failure of civilizations,” Matlock said. “It’s a pretty dramatic cost.” Global climate change will increase water scarcity in already water-stressed areas. Although agriculture no longer accounts for 90 percent of global water use, as it did in 1900, agricultural water use has increased fivefold since then. Competing with other sectors for limited water affects the many other uses that are not monetized, such as biodiversity. The Colorado and Ganges rivers offer examples of dramatic decreases in water discharge due to overallocation. Peak flows have not changed, but critical base flows have dropped considerably over time. “It’s hard to have a functional, viable aquatic ecosystem without the aquatic,” Matlock said. Rice, which accounts for 15 percent of human water use, presents another problem. But improvement is possible, Matlock said. Human Dimensions of Water for Food Production Anheuser-Busch InBev, for example, achieved 4.7 percent per-unit reductions in rice culture, saving 3.5 billion liters of water in five years. Water intake is only one issue; equally important is water effluent. From an ecological standpoint, given grossly limited incentive funding, Matlock believes profitable production practices should not be incentivized. “If you already have an incentive for conserving water − reducing soil erosion − then we don’t need to give you more money to do that which you ought to be doing anyway, because the marketplace will weed you out if you don’t perform,” he said. “It’s the things that we don’t incentivize, like preservation of riparian zones, that we should perhaps be incentivizing with our limited resources.” The Mesoamerican Barrier Reef System offers an example of the interconnectedness of agriculture effluent and environmental harm. Pollutants, particularly sediment and nutrients carried downstream from plantations to the Caribbean Sea, have the equivalent effect of a 10-degree temperature change, bleaching the coral reefs. Impacts that are acceptable with 6.7 billion people will not be with 9 billion, Matlock concluded. If management happens only to things that are measured, and not everything can be measured, which metrics are important and how can they be incentivized? “We have to shift our thinking from maximizing any one variable or metric to optimizing several key ones.

Chapter 6- A View from Agricultural Producers

Rainfed and Irrigated Production in Argentina Martin Pasman, an Argentine agronomist with a master’s degree in business administration, began his career as a consultant to farmers and has experience in Argentina, Uruguay, Paraguay and Brazil, where he was instrumental in helping to develop 80,000 hectares in the western part of the Cerrado area. His farming experience stems from his family’s farms, located in five areas of Argentina. Most are rainfed, but one area receives less than 500 millimeters of rain annually. Pasman also runs an irrigation business serving 80 percent of the Argentine market, giving him vast experience in developing irrigated land. Argentina is the second-largest South American country after Brazil and is one-third the size of the U.S. One-third of Argentina receives more than 800 millimeters of rain and depends upon rainfed agriculture, while the majority receives less than 800 millimeters. Argentina cultivates 30 million hectares per year, of which 2.2 million are irrigated. Total production output is 90 million metric tons, and about 70 percent of farmers in Argentina practice no-till agriculture. Pasman’s family came to Argentina from the U.S. around 1825, when it was primarily cattle country. His family brought the first Aberdeen Angus bull to Argentina and also helped develop agriculture. In the 1970s, the family farmed 6,000 hectares, of which only 500 were used for crops, yielding 3.5 tons of corn per hectare and 1.5 tons of wheat per hectare. They plowed the land and used few herbicides and no fertilizers. The majority of the land was used to raise 3,000 head of cattle, which were finished in natural pastures. Today, the family’s farm operation has expanded to 20,000 hectares, 15,000 of them used for agriculture. In the low-productivity land, they also manage 9,000 head of cattle in cow-calf operations, finishing the animals in American style feedlots. In rainfed fields, the Pasmans produce 8 tons of corn per hectare and 3 tons of wheat; under irrigation, they get 12 tons of corn and 6 tons of wheat. The most important crop, however, is soybeans. They also grow potatoes, corn and sunflower seeds for Monsanto Company. The farm uses 42 pivots to irrigate 4,000 hectares, and about 80 percent of the farm is double-cropped: wheat plus soybeans, seed corn plus soybeans, potato plus corn. Argentina uses a huge amount of herbicides and genetically modified crops, Pasman said, adding that his farm was one of the first to produce Roundup Ready® soybean seeds in 1994. A View from Agricultural Producers “The cornerstone of our production technology is no-till,” Pasman said, a technique used on the entire farm except the potato fields, which follow a rotation of one year of potatoes followed by three years of no-till. A corn crop follows the potato harvest in the same year. No-till improves water infiltration and water retention and reduces evaporation because the previous crops’ residue minimizes runoff and allows the soil to retain more water. No-till also reduces erosion risk and increases organic matter, improving oxidation and carbon circulation in the soil. It improves soil fertility, increases productivity and sustainability, and allows farming in difficult soils, particularly shallow soils of 3 inches. No-till uses less than half the water and less labor compared to conventional tillage, reducing production costs by 30 percent, Pasman concluded. “It is very important, the mix of no tillage with center pivot (irrigation) against traditional management.

Lithium Phthalocyanine: A Probe for Electron Paramagnetic Resonance Oximetry in Viable Biological Systems.

Lithium phthalocyanine (LiPc) is a prototype of another generation of synthetic, metallic-organic, paramagnetic crystallites that appear very useful for in vitro and in vivo electron paramagnetic resonance oximetry. The peak-to-peak line width of the electron paramagnetic resonance spectrum of LiPc is a linear function of the partial pressure of oxygen (pO2); this linear relation is independent of the medium surrounding the LiPc. It has an extremely exchange-narrowed spectrum (peak-to-peak line width = 14 mG in the absence of O2). Physicochemically LiPc is very stable; its response to pO2 does not change with conditions and environments (e.g., pH, temperature, redox conditions) likely to occur in viable biological systems. These characteristics provide the sensitivity, accuracy, and range to measure physiologically and pathologically pertinent O2 tensions (0.1-50 mmHg; 1 mmHg = 133 Pa). The application of LiPc in biological systems is demonstrated in measurements of pO2 in vivo in the heart, brain, and kidney of rats

Requirements for Collaboration With Schools: Public and Private Leaders Speak Out

If organizations are truly to collaborate, rather than merely cooperate, there will necessarily be a sacrifice of autonomy as they share visions, resources, decisions, and accountability

Creation of high mobility two-dimensional electron gases via strain induced polarization at an otherwise nonpolar complex oxide interface

The discovery of two-dimensional electron gases (2DEGs) in SrTiO3-based heterostructures provides new opportunities for nanoelectronics. Herein, we create a new type of oxide 2DEG by the epitaxial-strain-induced polarization at an otherwise nonpolar perovskite-type interface of CaZrO3/SrTiO3. Remarkably, this heterointerface is atomically sharp, and exhibits a high electron mobility exceeding 60,000 cm2V-1s-1 at low temperatures. The 2DEG carrier density exhibits a critical dependence on the film thickness, in good agreement with the polarization induced 2DEG scheme.Comment: 19 pages, 4 figs; Nano Letters,2015, published onlin