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Supplemental Digital Content is available in the text., Background Many patients who have traumatic brain injury experience a wide range of psychiatric and neurological symptoms (including impairment in functional status, cognition, and mood), and if persistent are referred to as persistent postconcussion syndrome (PCS). To our knowledge, this is the first study to broadly evaluate metabolic dysregulation in a heterogenous patient population meeting the criteria for PCS. Methods A total of 64 PCS patients and 37 healthy controls underwent 18F-fluorodeoxyglucose-PET (18F-FDG-PET) scanning, and 70 brain structures (including left and right structures where appropriate) were analyzed in each subject. Results Compared to the brains of healthy controls, those of PCS patients demonstrated 15 hypermetabolic and 23 hypometabolic regions. Metabolic changes in the brains of PCS patients were subsequently correlated with various indices of symptom severity, mood, and physical/cognitive function. Among PCS patients, increased metabolism in the right cingulate gyrus correlated with the severity of postconcussion symptoms. Conversely, increased metabolism in the left temporal lobe was associated with both improved mood and measures of adaptability/rehabilitation. Furthermore, increased metabolism in the bilateral orbitofrontal regions correlated with improved working memory. Conclusions Overall, these findings suggest a complex pattern of cerebral metabolism in PCS patients, with a mixture of hypometabolic and hypermetabolic regions that correlate with various symptoms, highlighting both potential pathological and compensatory mechanisms in PCS. The findings also suggest that FDG PET is useful for providing neurophysiological information in the evaluation of patients with PCS and may help guide future targeted therapies.

Emerging concerns over energy security and accelerating climate change have led to a global interest in developing a sustainable biofuel. Recently, it was determined that algal biofuels can be possibly cultured in a wastewater medium due to high levels of nutrients nitrogen, phosphorus, and potassium (NPK), reducing economic costs. Further efforts are needed in strain selection for cultivation in wastewater or inexpensive fertilizer. Common algal strains Nannochloropsis sp. and Chlorella sp. were studied to determine effects. Both strains were exposed to standard nutrients, which acted as controls, and high levels of NPK to simulate wastewater. The results revealed that NPK had a positive effect on turbidity and dissolved oxygen while decreasing the lipid productivities (measured via hexane solvent extraction) by an average of 36.5%. Specifically, Nannochloropsis sp. had overall higher values for all dependent variables. It is believed that under nutrient limiting conditions the cells deposited fatty acids in a triacylglycerol pathway. A follow-up experiment was performed using salinity as a novel method of decreasing biomass while maintaining lipid viability. Results revealed that freshwater algae can be cultivated in salinity levels between 10-15 ppt in order to increase lipid production. It is believed that while salinity osmotically interfered with the cell, lipid content increased, acting as a protective mechanism. Future research should focus on optimizing lipid production under stressed conditions using genetic manipulation of the TAG biosynthesis pathway.

Emerging concerns over energy security and accelerating climate change have led to a global interest in developing a sustainable biofuel. Recently, it was determined that algal biofuels can be possibly cultured in a wastewater medium due to high levels of nutrients nitrogen, phosphorus, and potassium (NPK), reducing economic costs. Further efforts are needed in strain selection for cultivation in wastewater or inexpensive fertilizer. Common algal strains Nannochloropsis sp. and Chlorella sp. were studied to determine effects. Both strains were exposed to standard nutrients, which acted as controls, and high levels of NPK to simulate wastewater. The results revealed that NPK had a positive effect on turbidity and dissolved oxygen while decreasing the lipid productivities (measured via hexane solvent extraction) by an average of 36.5%. Specifically, Nannochloropsis sp. had overall higher values for all dependent variables. It is believed that under nutrient limiting conditions the cells deposited fatty acids in a triacylglycerol pathway. A follow-up experiment was performed using salinity as a novel method of decreasing biomass while maintaining lipid viability. Results revealed that freshwater algae can be cultivated in salinity levels between 10-15 ppt in order to increase lipid production. It is believed that while salinity osmotically interfered with the cell, lipid content increased, acting as a protective mechanism. Future research should focus on optimizing lipid production under stressed conditions using genetic manipulation of the TAG biosynthesis pathway.