PERFORMANCE OF FISH LARVAE: EFFECTS OF ATRAZINE,

To my husband, Rafael Perez, to whom I owe everything, who has been with me through the “good and the bad”. To my son, Diego T. Perez, and my daughter, Cecilia A. Perez, who have always brightened my day with laughter and love. And to my parents, Alvaro Alvarez and Marie Cecilie d’Otreppe de Bouvette, who, without ever a doubt, have supported me on every decision I have made. Thank you. Acknowledgements I wish to thank my adviser Dr. Lee A. Fuiman, for his guidance, support, and encouragement. I am also grateful to the members of my committee, Dr. David P. Crews, Dr. G. Joan Holt, Dr. B. Scott Nunez and Dr. Peter Thomas for their helpful suggestions and critical review of this dissertation. Thanks to my laboratory mates; Hunter Samberson and Brie Sarkisian for their help with fish rearing; Ian McCarthy for helping with fish rearing and collection of data, and Kiersten Madden for her support and critique of this work. My special thanks to Rafael Perez, Scott Applebaum, and Ian McCarthy for discussion in the development of the research presented here. I am sincerely thankful to all my friends at the Marine Science Institute and Port Aransas for their help and support, without whom this dissertation would not have happened. v SIGNIFICANCE OF ENVIRONMENTALLY REALISTI

Heart sparing radiotherapy techniques in breast cancer: A focus on deep inspiration breath hold

Adjuvant radiation therapy is a critical component of breast cancer management. However, when breast cancer patients receive incidental radiation to the heart, there is an increased risk of cardiac disease and mortality. This is most common for patients with left-sided breast cancers and those receiving nodal irradiation as part of treatment. The overall risk of cardiac toxicity increases 4-16% with each Gray increase in mean heart radiation dose, with data suggesting that no lower limit exists which would eliminate cardiac risk entirely. Radiation techniques have improved over time, leading to lower cardiac radiation exposure than in the past. This decline is expected to reduce the incidence of radiation-induced heart dysfunction in patients. Deep inspiration breath hold (DIBH) is one such technique that was developed to reduce the risk of cardiac death and coronary events. DIBH is a non-invasive approach that capitalizes on the natural physiology of the respiratory cycle to increase the distance between the heart and the therapeutic target throughout the course of radiation therapy. DIBH has been shown to decrease the mean incidental radiation doses to the heart and left anterior descending coronary artery by approximately 20-70%. In this review, we summarize different techniques for DIBH and discuss recent data on this technique

Producing Omega-3 Polyunsaturated Fatty Acids: A Review of Sustainable Sources and Future Trends for the EPA and DHA Market

Omega-3 polyunsaturated fatty acids (Omega-3 PUFA) are recognized as being essential compounds for human nutrition and health. The human body generates only low levels of Omega-3 PUFA. Conventional sources of Omega-3 PUFA are from marine origin. However, the global growth of population combined with a better consumer understanding about healthy nutrition leads to the fact that traditional sources are exhausted and therefore not enough to satisfy the demand of Omega-3 PUFA for human diet as well as aquaculture. Microalgae cultivated under heterotrophic conditions is increasingly recognized as a suitable technology for the production of the Omega-3 PUFA. The high cost of using glucose as main carbon source for cultivation is the main challenge to establish economical feasible production processes. The latest relevant studies provide alternative pathways for Omega-3 PUFA production. As preliminary results show, volatile fatty acids (VFA) recovered from waste stream could be a good alternative to the use of glucose as carbon source in microalgae cultivation. The purpose of this paper is to highlight the actual situation of Omega-3 PUFA production, sources and market request to provide a summary on sustainable sources that are being investigated as well as present and future market trends in Omega-3 market.The authors would like to thank the European project VOLATILE. The project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 720777

Graphene Grown on Ge(001) from Atomic Source

Among the many anticipated applications of graphene, some - such as transistors for Si microelectronics - would greatly benefit from the possibility to deposit graphene directly on a semiconductor grown on a Si wafer. We report that Ge(001) layers on Si(001) wafers can be uniformly covered with graphene at temperatures between 800{\deg}C and the melting temperature of Ge. The graphene is closed, with sheet resistivity strongly decreasing with growth temperature, weakly decreasing with the amount of deposited C, and reaching down to 2 kOhm/sq. Activation energy of surface roughness is low (about 0.66 eV) and constant throughout the range of temperatures in which graphene is formed. Density functional theory calculations indicate that the major physical processes affecting the growth are: (1) substitution of Ge in surface dimers by C, (2) interaction between C clusters and Ge monomers, and (3) formation of chemical bonds between graphene edge and Ge(001), and that the processes 1 and 2 are surpassed by CH$_{2}$ surface diffusion when the C atoms are delivered from CH$_{4}$. The results of this study indicate that graphene can be produced directly at the active region of the transistor in a process compatible with the Si technology

A Feasibility Study of Supply and Demand for Diabetes Prevention Programs in North Carolina

Diabetes Prevention Programs (DPPs) have shown that healthy eating and moderate physical activity are effective ways of delaying and preventing type 2 diabetes in people with impaired glucose tolerance. We assessed willingness to pay for DPPs from the perspective of potential recipients and the cost of providing these programs from the perspective of community health centers and local health departments in North Carolina

Production of Docosahexaenoic Acid and Odd-Chain Fatty Acids by Microalgae Schizochytrium limacinum Grown on Waste-Derived Volatile Fatty Acids

Heterotrophic microalgae are recognized as a source of bioactive compounds. However, there are still some drawbacks for their use at an industrial scale associated with the high cost of glucose, the main carbon source in heterotrophic cultures. In recent years, significant efforts have been made to investigate more sustainable carbon sources to produce biomass. In this study, the capacity of Schizochytrium limacinum to grow on waste-derived volatile fatty acids and the effect that their use produces on biomass and fatty acids profiles were investigated. Acetic, propionic, butyric, valeric and caproic acid were evaluated independently, as well as in a synthetic mixture (VFA). The use of acetic and butyric resulted in a good biomass productivity, while the use of valeric and propionic acid resulted in higher content of odd-chain fatty acids (OCFA), increasingly investigated due to their potential benefits for human health. The use of industrial waste-derived VFA as a potential carbon source was validated through the utilization of biowaste derived effluents from a volatile fatty acid platform. The biomass produced was of 18.5 g/L, 54.0% lipids, 46.3% docosahexaenoic acid (DHA) and 25.0% OCFA, concluding that waste derived VFA can produce DHA and OCFA in a suitable ratio of DHA/OCFA with potential industrial applications.The authors would like to thank the European project VOLATILE. The project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 720777

Non-consensus GLI binding sites in Hedgehog target gene regulation

BACKGROUND: The GLI transcription factors, mediators of the hedgehog signal bind with high affinity to the consensus sequence GACCACCCA. The affinity of variant single substitutions in GLI binding sites has been measured systematically, but the affinities of the variant binding sites appears low compared to the frequency of occurrence of variant sites in known GLI target gene promoters. RESULTS: We quantified transcriptional activation by GLI using PTCH1 promoter based luciferase reporters containing all single substitutions of the GLI consensus binding site. As expected variants with very low affinity did not activate the reporter. Many lower affinity binding sequences are, however, functional in the presence of moderate GLI concentration. Using two natural non-consensus GLI site promoters we showed that substitution of the variant sequences by consensus leads to comparable activity. CONCLUSIONS: Variant GLI binding sites with relatively low affinity can within natural promoters lead to strong transcriptional activation. This may facilitate the identification of additional direct GLI target genes.(VLID)218887

Comparison between Thermophysical and Tribological Properties of Two Engine Lubricant Additives: Electrochemically Exfoliated Graphene and Molybdenum Disulfide Nanoplatelets

Recently graphene and other 2D materials were suggested as nano additives to enhance the performance of nanolubricants and reducing friction and wear-related failures in moving mechanical parts. Nevertheless, to our knowledge there are no previous studies on electrochemical exfoliated nanomaterials as lubricant additives. In this work, engine oil-based nanolubricants were developed via two-steps method using two different 2D nanomaterials: a carbon-based nano additive, graphene nanoplatelets (GNP) and a sulphide nanomaterial, molybdenum disulfide (MoS2) nanoplatelets (MSNP). The influence of these nano additives on the thermophysical properties of the nanolubricants, such as viscosity index, density and wettability, was investigated. The unique features of the electrochemical exfoliated GNP and MSNP allow the formulation of nanolubricant with unusual thermophysical properties. Both the viscosity and density of the nanolubricants decreased by increasing the nanoplatelets loading. The effect of the nano additives loading and temperature on the tribological properties of nanolubricants was investigated using two different test configurations: reciprocating ball-on-plate and rotational ball-on-three-pins. The tribological specimens were analysed by scanning electron microscopy (SEM) and 3D profiler in order to evaluate the wear. The results showed significant improvement in the antifriction and anti-wear properties, for the 2D-materials-based nanolubricants as compared with the engine oil, using different contact conditions. For the reciprocal friction tests, maximum friction and worn area reductions of 20% and 22% were achieved for the concentrations of 0.10 wt% and 0.20 wt% GNP, respectively. Besides, the best anti-wear performance was found for the nanolubricant containing 0.05 wt% MSNP in rotational configuration test, with reductions of 42% and 60% in the scar width and depth, respectively, with respect to the engine oil.S

An assessment of ADAMs in bone cells: absence of TACE activity prevents osteoclast recruitment and the formation of the marrow cavity in developing long bones

AbstractADAMs (A Disintegrin And Metalloprotease domain) are metalloprotease–disintegrin proteins that have been implicated in cell adhesion, protein ectodomain shedding, matrix protein degradation and cell fusion. Since such events are critical for bone resorption and osteoclast recruitment, we investigated whether they require ADAMs. We report here which ADAMs we have identified in bone cells, as well as our analysis of the generation, migration and resorptive activity of osteoclasts in developing metatarsals of mouse embryos lacking catalytically active ADAM 17 [TNFα converting enzyme (TACE)]. The absence of TACE activity still allowed the generation of cells showing an osteoclastic phenotype, but prevented their migration into the core of the diaphysis and the subsequent formation of marrow cavity. This suggests a role of TACE in the recruitment of osteoclasts to future resorption sites