Regulatory Mechanisms in Biosystems (E-Journal - Dnipro National University)
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Felix Blucher as a toddler, son of Richard Blucher
No full textFelix Blucher as a toddler, son of Richard Bluche
Focused Flows to Maintain Natural Nursery Habitats
No full textRegulatory standards for environmental flows to estuaries are not common, but they are required in Texas. This has led to adoption of complex freshwater inflow regimes that reflect seasonal and yearly fluctuations that vary geographically throughout the state. The flow regimes are based on dilution of saline water with fresh water in whole systems. Because the estuaries are large lagoons, large volumes of fresh water are required to meet standards. However, this volume of water is not available during dry periods. We present a new concept, focused flows, for lower flow volumes that would maintain the ecological health of the upper reaches of estuaries during droughts. The concept is based on maintaining ecological integrity of nursery habitats, which is an important ecological function of estuaries. These focused flows would protect nursery habitats during droughts and allow estuaries to recover more quickly when the hydrology returns to average or higher flow periods. This approach could be applied globally where increasing water infrastructure and deficits are a concern or increasing aridity due to climate change is reducing river flows to coasts
Biomimetic iron complexes for the oxidation of C-H bonds in hydrocarbons
No full textWith the rapid growth in transportation and industry, petroleum and other types of fossil fuels (coal, heavy oil) are heavily used for energy production. The consumption of these types of energy resources pose a serious environmental concern because of the production of greenhouse gases such as carbon dioxide, methane, nitrous oxide, and chlorofluorocarbons (CFCs) which are the primary reasons for climate change. This makes the development of cheaper and cleaner energy more important in modern society. Conversion of methane into liquid fuel such as methanol has become a promising goal for future petrochemical derivatives and decreasing petroleum dependence. Methane is the primary component of natural gas which is highly abundant on earth. Methane is used as a raw material to produce methanol which is further used as fuel to generate electricity. However, the conversion of methane into methanol is carried out at high temperature and pressure and this process is energy consuming. This makes methane oxidation catalysts high in demand. In recent decades, transition metal complexes have proven to be efficient and powerful catalysts for various oxidative transformations. Specifically, mononuclear and di-nuclear metal complexes now are widely applied as catalysts for the oxidation of organic substrates and water. Transition metals such as Mn, Fe, Co, Ni and Cu have been recognized as cheap, environmentally friendly and effective catalysts for C-H activation. Specifically, iron is the most attractive metal because it’s very inexpensive (most earth-abundant transition metal), displays high oxidation states (required in catalysis), and is relatively non-toxic. In this research, we will design and develop routes for synthesizing iron complexes that can serve as cheap and efficient catalysts for methane oxidation (or C-H activation). This is the foundation for future research aiming at converting inert hydrocarbons into useful petrochemical derivatives.Physical and Environmental SciencesCollege of Science and Engineerin
White Flowers of Yucca Faxoniana Plants
No full textClose up of White Flowers of Yucca Faxoniana Plants along side a roa
Letter to Dee from Georgia O'Keeffe, Mother of American Modernism.
No full textLetter to Dee from Georgia O'Keeffe, Mother of American Modernism
Angled View of Pink Thistle Thorn Flower with a Bumblebee
No full textAngled View of Pink Thistle Thorn Flower with a Bumblebe
Responses of benthic calcifying algae to ocean acidification differ between laboratory and field settings
No full textAccurately predicting the effects of ocean and coastal acidification on marine ecosystems requires understanding how responses scale from laboratory experiments to the natural world. Using benthic calcifying macroalgae as a model system, we performed a semi-quantitative synthesis to compare directional responses between laboratory experiments and field studies. Variability in ecological, spatial, and temporal scales across studies, and the disparity in the number of responses documented in laboratory and field settings, make direct comparisons difficult. Despite these differences, some responses, including community-level measurements, were consistent across laboratory and field studies. However, there were also mismatches in the directionality of many responses with more negative acidification impacts reported in laboratory experiments. Recommendations to improve our ability to scale responses include: (i) developing novel approaches to allow measurements of the same responses in laboratory and field settings, and (ii) researching understudied calcifying benthic macroalgal species and responses. Incorporating these guidelines into research programs will yield data more suitable for robust meta-analyses and will facilitate the development of ecosystem models that incorporate proper scaling of organismal responses to in situ acidification. This, in turn, will allow for more accurate predictions of future changes in ecosystem health and function in a rapidly changing natural climate