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AN ECONOMICAL SYNTHETIC ROUTE IN THE OCEAN FOR THE MARINE NATURAL PRODUCT, BRYOSTATIN
No full textBryostatin is a marine natural product found in minute amounts in nature. Cost 17 million USD/gram, this molecule targets latent HIV reservoirs, has potential for slowing the progression of Alzheimer\u27s, and demonstrates strong anti-cancer properties. We have developed an economical synthesis of bryostatin through the creation of a bioreactor that cultivates a symbiotic bacterium which lives on the bryosome B. Nerintina. This bioreactor is comprised of inexpensive organic materials providing essential nutrients which promotes the growth of the bacterium. Our bioreactor was deployed off the Gulf Coast for a short period to attract our symbiotic bacterium. This bioreactor was returned to the lab where it was monitored weekly for 2 months with sample extraction every other day. Each sample was labeled and stored in cold storage to prevent the degradation of bryostatin. After our collection period, we ran each sample through a UV Spectrometer to determine the possible presence of Bryostatin. Promising samples were, then, ran through a liquid chromatography mass spectrometer to determine the different types of Bryostatin present
ORIENTATION OF MOLECULES IN STRETCHED FILMS**
No full textThe extent of orientation of several chemical species embedded in stretched polyvinylchloride(PVC) films is investigated. The orientation of the PVC film is also measured. The extent of orientation versus film stretch ratio and the linear dichroism (LD) is correlated to transition moment directions, if known. The LD is also correlated to molecular shape
SYNTHESIS OF HYDROGELS AND ADSORPTION/DESORPTION KINETICS OF UREA**
No full textHydrogels, natural or synthetic polymers, that are being used in medicine and agriculture also find their applications in environmental chemistry and engineering. The superior characteristics of hydrogels, including high capacity of water retention and adsorption of solutes, make hydrogels promising for recovery of nutrients from aqueous solutions. As valuable nutrients are being lost to environment to cause pollution, the recovery or recycle of the nutrients from their sources can be achieved by utilizing the hydrogels properties. Cellulose-base and acrylamide-base hydrogels were synthesized and characterized for their chemical structures and functional groups using TFIR spectroscopy, and further tested for swelling behavior and the adsorption and desorption capabilities by evaluating the concentration of urea using a TOC/TN instrument and mass balance. This study focuses also on their kinetic behavior both in adsorption and desorption of urea from an aqueous solution, which simulates the urea uptake from human urine and the release to a solution for recycling. Preliminary results show higher swelling capacity of acrylamide-base hydrogels than cellulose-base counterpart (188 +/- 54 % vs 22 +/- 1.0 %) and higher adsorption and desorption as well (19.1 mg N/g hydrogel vs 9.0 mg N/g, 11.0 mg N/L solution vs 4.1 mg N/L, respectively). Isotherm tests and kinetic studies are being conducted to elucidate the correlation among the chemical structures, the hydrogels’ performance and the effect of crosslinking agents. The synthesis of more environmentally friendly hydrogels are also being studied by employing other monomers and cross-linkers, and the production of more efficient adsorbent/desorbent will follow by adopting novel synthetic strategies involving hybrid-copolymers and UV initiated polymerization. The outcome of this study is expected to contribute to reuse of nutrients and reduction of the load of water treatment
HITCHHIKING BEHAVIOR OF A WORKER SUBCASTE IN LEAF-CUTTER ANTS (ATTA CEPHALOTES)
No full textThe minim worker subcaste of leaf-cutter ants (Atta spp.) exhibits hitchhiking behavior in foraging columns. Minims frequently ride (hitchhike) on cut leaf fragments being transported to the subterranean nest by forager ants. Minims remove fungal contaminants from fragments that might otherwise destroy the mutualistic Leucoagaricus fungi in the nest that nourish the ants. They also guard against parasitoid phorid flies that attempt to lay eggs on the head of laden foragers. In addition to fungal and phorid defense, minims also obtain nourishment from the sap of cut leaves (sap obtention). We observed Atta cephalotes minims in a tropical cloud forest near San Luis, Monteverde, Costa Rica in June 2019 to determine whether their hitchhiking behavior is (a) more consistent with defense or sap obtention and (b) whether this behavior differed in day versus night foraging columns. Hitchhikers in eight foraging columns were monitored during the day (1300-1600 h) and night (1900-2130 h). Hitchhikers were chosen at random in each foraging column and each ant was filmed (iPhone camera) for 30 s. We filmed 209 ants, 94 in day columns and 115 in night columns. During video replay, the ant’s head posture and its position on the leaf fragment was recorded as consistent with either defense or sap obtention. A contingency Chi-square test revealed that posture, position on the leaf fragment, and foraging time (day versus night) were mutually dependent (Χ2 = 9. 49, 0.005 \u3e P \u3e 0.001). Minims in nighttime and daytime foraging columns were most frequently observed in postures and positions consistent with phorid defense. Head posture and position associated with sap obtention were infrequent. The frequency of nighttime hitchhikers exhibiting phorid defense behavior was greater than that of daytime hitchhikers. Because phorid parasitoids are active only at day, defensive postures at night that are consistent with phorid defense is puzzling and warrants further investigation
LOOKING FOR LOCAL ADAPTATIONS: ARE A SUBSET OF THE IRIDOVIRUS CORE GENES SUITABLE FOR RECONSTRUCTING PHYLOGENETIC RELATIONSHIPS IN AMBYSTOMA TIGRINUM VIRUS ISOLATES FROM THE SOUTHWESTERN USA?**
No full textAmbystoma tigrinum virus (ATV) is a species of Ranavirus, which is a member of the viral family Iridoviridae. Ranaviruses are globally emerging pathogens of amphibians, fish and reptiles. However, ATV appears to be predominantly located in the Southwestern USA where it affects amphibians. It has previously been established that ATV has local variation within the Southwestern USA using a subset of its genes, however not all of the genes used were core genes. Iridoviruses have 26 core genes that are considered to be conserved, and these genes have not all been explored as possible markers for local variation. Here we will examine the phylogeny created by five different Iridovirus core genes (ORF 10L, 25R, 38R, 58R, and 80R) and compare this to the known phylogeny that includes other loci that are not members of the core for 15 strains of ATV. This will let us determine the utility of these core genes as markers for local variation. We plan to do this by obtaining the sequences of each ORF from GenBank. The sequences will then be aligned using a MAFTT server. The aligned sequences will be imported into MEGA 6, and a nucleotide substitution model best-fit will be run. The best-fit substitution model will then be used with the aligned sequences to build maximum likelihood trees for each locus. Based on preliminary analyses, we expect that there will be little to no variation between the different strains of ATV and that we will not be able to discern local variation using these conserved genes
BLOODROOT EXTRACT DECREASES TNF-α LEVELS IN THP-1 CELLS
No full textStudies have shown that sanguinarine, which is isolated from the bloodroot plant (Sanguinaria canadensis), has anti-inflammatory properties. TNF-α is cytokine that is created by cells, including macrophages, in response to an inflammatory insult. THP-1 monocytes, which can differentiate into macrophages following phorbol 12-myristate 13-acetate (PMA) exposure, are a common model used for examining inflammation. Lipopolysaccharide (LPS) treatment of THP-1 cells has been shown to cause an increase in TNF-α expression. In our studies, we tested THP-1 cells exposed to LPS in the presence or absence of bloodroot extract to determine if pre-treatment of the cells with these extracts can prevent TNF-α expression. Extracts were made using 0.125 g/ml of dried bloodroot and either DMSO, ethanol, or hot water as the solvent. TNF-α levels were determined using an ELISA kit and compared to provided standards. Results indicate that all three of our bloodroot extracts were able to decrease TNF-α expression by more than 99.9% (p\u3c0.01). These results indicate that bloodroot extract, dissolved in any of the three solvents tested, prevents TNF-α from being produced in differentiated THP-1 cells. Our findings suggest that bloodroot extracts may be useful in the prevention or treatment of inflammation
Absorption of External Mechanical Vibrations into Buildings by Particulate Dampers.
No full textAbsorption of mechanical vibration at audible frequencies are studied with the goal of mitigating the transmission of external vibrations into the building structures. Attenuation of vibration by particulates depend mainly on their mechanical properties of solid particulates and their degree of compactness. It is known that building vibrations can be significantly damped by surrounding the foundation with particulate materials of specific characteristics. This research is to optimize particulate dampers to absorb the large band of vibrations in the audible frequency range. Experimental results show that particulates behave as band-pass filters for mechanical vibrations transmitted through them. Samples of particulate dampers are subjected to vibrations at different frequency and amplitude and vibration attenuation versus frequency are measured. The goal is to determine optimal vibration dampers to mitigate the transmission of external mechanical vibrations into the buildings
Advances in Renewable Energy: Focusing on Unusual Methods of Energy Conversion
No full textAdvances in unusual types of renewable energy are expanding the possibilities for different types of resources that can be used to power electronics, power plants, smart phones, and other technology. Resources such as solar and wind power are most common, but other more unusual types such as cocoa shells, dance floors that convert kinetic energy into electricity, algae lipid oils, and geothermal energy are going through advances that might make it possible to move away from fossil fuels and focus on resources that are renewable. Common sources of renewable energy such as solar power are being explored in more unique ways such as space-based solar panels. Waves and tidal energy are also experiencing advances through methods of hydro turbines
FEMALE FERTILITY ANNOUNCEMENT: DO FEMALE HOUSE WRENS (TROGLODYTES AEDON) ADJUST SINGING BEHAVIOR PRIOR TO CLUTCH INITIATION?**
No full textDespite evidence that many male songbirds adjust their vocal behavior when their mate is fertile, few studies have explored whether females also adjust patterns of singing during early stages of breeding. For females, increased song output prior to clutch initiation may increase the likelihood of fertilization success. In this study, we test the hypothesis that female house wrens (Troglodytes aedon) that increase song output during their fertile period have higher fitness. We recorded females breeding in nest boxes prior to clutch initiation, quantified song output, and defined reproductive success as the number of eggs laid and offspring fledged. Our study is an important step towards understanding the potential consequences of female singing behavior on fitness
Definition and Discussion of Some Fundamental Concepts and Issues from the Perspective of Science
No full textn the process of creating new scientific ad scholarly knowledge, certain concepts and issues arise. These items have general applicability; i.e. are not specifically tied to any particular field of science and often are of general value for producing insights into other areas of research and knowledge creation. We consider ten such items and provide brief and concise definitions and discussions on their relationship with and importance to science, with the emphasis on the natural sciences. We also provide reasons why they should be better known to individuals considering themselves to be educated persons