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- Creator:
- Loyd, Sean
- Description:
- Major hydrocarbon accumulations occur in traps associated with salt domes. Whereas some of these hydrocarbons remain to be extracted for economic use, significant amounts have degraded in the subsurface, yielding mineral precipitates as byproducts. Salt domes of the Gulf of Mexico Basin typically exhibit extensive deposits of carbonate that form as cap rock atop salt structures. Despite previous efforts to model cap rock formation, the details of subsurface reactions (including the role of microorganisms) remain largely unknown. Here we show that cap rock mineral precipitation occurred via closed-system sulfate reduction, as indicated by new sulfur isotope data. 13C-depleted carbonate carbon isotope compositions and low clumped isotope-derived carbonate formation temperatures indicate that microbial, sulfate-dependent, anaerobic oxidation of methane (AOM) contributed to carbonate formation. These findings suggest that AOM serves as an unrecognized methane sink that reduces methane emissions in salt dome settings perhaps associated with an extensive, deep subsurface biosphere.
- Resource Type:
- Article
- Campus Tesim:
- Fullerton
- Department:
- Department of Geological Sciences
- Creator:
- Galpin, Andrew
- Description:
- Human skeletal muscle fibers exist across a continuum of slow → fast-twitch. The amount of each fiber type (FT) influences muscle performance but remains largely unexplored in elite athletes, particularly from strength/power sports. To address this nescience, vastus lateralis (VL) biopsies were performed on World/Olympic (female, n = 6, “WCF”) and National-caliber (female, n = 9, “NCF”; and male, n = 6, “NCM”) American weightlifters. Participant accolades included 3 Olympic Games, 19 World Championships, 25 National records, and >170 National/International medals. Samples were analyzed for myosin heavy chain (MHC) content via SDS-PAGE using two distinct techniques: single fiber (SF) distribution (%) and homogenate (HG) composition. The main finding was that these athletes displayed the highest pure MHC IIa concentrations ever reported in healthy VL (23±9% I, 5±3% I/IIa, 67±13% IIa, and 6±10% IIa/IIx), with WCF expressing a notable 71±17% (NCF = 67±8%, NCM = 63±16%). No pure MHC IIx were found with SF. Secondary analysis revealed the heavyweights accounted for 91% of the MHC IIa/IIx fibers, which caused a correlation between this FT and body mass. Additionally, when compared to SF, HG overestimated MHC I (23±9 vs. 31±9%) and IIx (0±0 vs. 3±6%) by misclassifying I/IIa fibers as I and IIa/IIx fibers as IIx, highlighting the limitation of HG as a measure of isoform distribution. These results collectively suggest that athlete caliber (World vs. National) and/or years competing in the sport determine FT% more than sex, particularly for MHC IIa. The extreme fast-twitch myofiber abundance likely explains how elite weightlifters generate high forces in rapid time-frames.
- Resource Type:
- Article
- Campus Tesim:
- Fullerton
- Department:
- Department of Kinesiology
- Creator:
- Lockie, Robert
- Description:
- This study analyzed the effects physical fitness may have on reasons for academy separation in law enforcement recruits. A retrospective analysis was conducted on 401 recruits; 330 recruits graduated (GRAD), and 71 recruits separated at various times during academy. Twenty-eight recruits separated for personal reasons (SEPPR); 18 due to physical training failures (i.e., poor fitness) or injury (SEPFI); and 25 due to academic or scenario failures (SEPAS). Fitness testing occurred prior to academy, and included: Push-ups and sit-ups in 60s; a 75-yard pursuit run (75PR); vertical jump; medicine ball throw; and multistage fitness test (MSFT). A one-way ANOVA with Bonferroni post hoc compared between-group fitness test performance. A multiple stepwise regression calculated whether recruit characteristics or fitness could predict separation. The GRAD group was younger than the SEPAS group (p < 0.01), faster in the 75PR than the SEPFI group (p = 0.02), and completed more MSFT shuttles than the SEPPR and SEPFI groups (p = 0.01). Age predicted GRAD and SEPAS group inclusion; MSFT predicted GRAD, SEPPR, and SEPFI group inclusion. Recruits who had superior high-intensity running capacity (75PR) and aerobic fitness (MSFT) should have a better chance of completing academy. However, this could be influenced by training practices adopted during academy.
- Resource Type:
- Article
- Campus Tesim:
- Fullerton
- Department:
- Department of Kinesiology
14. The Role of Regional Contrast Changes and Asymmetry in Facial Attractiveness Related to Cosmetic Use
- Creator:
- Peissig, Jessie
- Description:
- This study collected behavioral data for testing how regional contrast changes due to the addition of cosmetics would affect attractiveness ratings. In addition, we used an established model of asymmetry to look for a correlation between changes in attractiveness related to the application of cosmetics to specific regions of the face and changes in symmetry. Using this asymmetry model we compared female faces with and without makeup. Specifically, we used a highly controlled set of grayscale faces in which makeup application was standardized to explore these issues from a perceptual perspective. The human data showed that adding upper eye makeup significantly increased attractiveness ratings. In contrast, increases in contrast to the lower eyes and lips did not lead to increases in attractiveness ratings; application of cosmetics to the lower eyes led to a significant decrease in attractiveness. We found that for the makeup condition that led to increased attractiveness, asymmetry did not change significantly when makeup was applied to the female faces. This suggests a role for mechanisms other than symmetry related to increases in attractiveness related to makeup use in females.
- Resource Type:
- Article
- Campus Tesim:
- Fullerton
- Department:
- Department of Psychology
- Creator:
- Tomaszewski, Robert
- Description:
- Identifying research gaps and generating research questions are often a first step in developing ideas for writing a research paper or grant proposal. The concept of substance-based bibliometrics uses the counts of substances in the scientific literature to better understand, assess, and clarify the state and impact of information in the chemical sciences. Connecting substances indexed to specific bioactivity or target indicators can lead to assessing the biochemical, biological, and medicinal relevance of substances as well as developing ideas for expanding drug design and discovery through identifying and modifying the structural features of molecules. This study uses Chemical Abstracts through the SciFinder database to count for the occurrence of substances in the scientific literature. The study sets out search strategies for discovering potential research gaps and new ideas through visualization of chemical structures with known bioactivity and target indicators. The author recommends that subject librarians integrate research gap training in their bibliographic instruction classes, particularly to upper-level undergraduate and graduate chemistry students.
- Resource Type:
- Article
- Campus Tesim:
- Fullerton
- Department:
- Pollak Library
- Creator:
- Lockie, Robert
- Description:
- This study determined relationships between an agency-specific fitness test battery (PT500), and a work sample test battery (WSTB) in law enforcement recruits. Retrospective analysis on 219 males and 34 females from one agency was conducted. The PT500 comprised: push-ups, sit-ups, and mountain climbers in 120 s; pull-ups; and 201 m and 2.4 km runs. The WSTB comprised: 99 yard (90.53 m) obstacle course (99OC); body drag (BD) with a 165 pound (75 kg) dummy; 6 foot (1.83 m) chain link fence (CLF) and solid wall (SW) climb; and 500 yard (457.2 m) run (500R). Partial correlations, controlling for sex, calculated PT500 and WSTB relationships (p < 0.05). Stepwise regression determined whether fitness predicted WSTB performance. The 500R related to all PT500 assessments (r range = -0.127⁻0.574), 99OC related to all bar push-ups and mountain climbers, and BD related to none. The CLF related to sit-ups, pull-ups, and 2.4 km run; SW related to mountain climbers, pull-ups, and 2.4 km run (r range = -0.127⁻-0.315). Push-ups, pull-ups, and 2.4 km run were involved in predictive relationships for 99OC, CLF, SW, and 500R (r² range = 0.217⁻0.500). To perform better in the WSTB and job-specific tasks, developing upper-body strength and aerobic fitness may be beneficial.
- Resource Type:
- Article
- Campus Tesim:
- Fullerton
- Department:
- Department of Kinesiology
- Creator:
- Ramirez, Maria Soledad
- Description:
- Acinetobacter baumannii is a multidrug resistant nosocomial pathogen that shows an outstanding ability to undergo genetic exchange, thereby acquiring different traits that contribute to its success. In this work, we identified genetic features of an indigo-pigmented A. baumannii strain (Ab33405) that belongs to the clonal complex CC113B/CC79P. Ab33405 possesses a high number of genes coding for antibiotic resistance and virulence factors that may contribute to its survival, not only in the human host, but also in the hospital environment. Thirteen genes conferring resistance to different antibiotic families (trimethoprim, florfenicol, β-lactams, aminoglycosides and sulfonamide) as well as the adeIJK genes and the capsule locus (KL) and outer core locus (OCL) were identified. Ab33405 includes 250 unique genes and a significant number of elements associated with Horizontal Gene Transfer, such as insertion sequences and transposons, genomic islands and prophage sequences. Also, the indigo-pigmented uncommon phenotype that could be associated with the monooxygenase or dioxygenase enzyme coded for by the iacA gene within the iac cluster was probably conferred by insertion of a 18-kb DNA fragment into the iacG gene belonging to this cluster. The Ab33405 genome includes all type VI secretion system genes and killing assays showed the ability of Ab33045 to kill Escherichia coli. In addition, Ab33405 can modulate susceptibility antibiotics when exposed to blue light.
- Resource Type:
- Article
- Campus Tesim:
- Fullerton
- Department:
- Department of Biological Sciences
- Creator:
- James, Sagil
- Description:
- Dye-Sensitized Solar Cells (DSSC) are third generation solar cells used as an alternative to traditional silicon solar cells. DSSCs are characterized by their durability, easy handling and ability to perform better under diverse lighting conditions which makes them an ideal choice for indoor applications. However, DSSCs suffer from several limitations including low efficiencies, susceptibility to electrolyte leakage under extreme weather conditions, and the need for expensive materials and fabrication techniques which limits their large-scale industrial applications. Addressing these limitations through efficient design and manufacturing techniques are critical in ensuring that the DSSCs transform from the current small-scale laboratory levels to sizeable industrial production. This research attempts to address some of these significant limitations by introducing the concepts of nature-inspired fractal-based design followed by the additive manufacturing process to fabricate cost-effective, flexible counter electrodes for DSSCs. The new conceptual fractal-based design counter electrodes overcome the limitations of conventional planar designs by significantly increasing the number of active reaction sites which enhances the catalytic activity thereby improving the performance. The fabrication of these innovative fractal designs is realized through cost-effective manufacturing techniques including additive manufacturing and selective electrochemical co-deposition processes. The results of the study suggest that the fractal-based counter electrodes perform better than conventional designs. Additionally, the fractal designs and additive manufacturing technology help in addressing the problems of electrolyte leakage, cost of fabrication, and scalability of DSSCs.
- Resource Type:
- Article
- Campus Tesim:
- Fullerton
- Department:
- Department of Mechanical Engineering
- Creator:
- Ahmed, Wylie
- Description:
- The intracellular environment is a dynamic space filled with various organelles moving in all directions. Included in this diverse group of organelles are vesicles, which are involved in transport of molecular cargo throughout the cell. Vesicles move in either a directed or non-directed fashion, often depending on interactions with cytoskeletal proteins such as microtubules, actin filaments, and molecular motors. How these proteins affect the local fluctuations of vesicles in the cytoplasm is not clear since they have the potential to both facilitate and impede movement. Here we show that vesicle mobility is significantly affected by myosin-II, even though it is not a cargo transport motor. We find that myosin-II activity increases the effective diffusivity of vesicles and its inhibition facilitates longer states of non-directed motion. Our study suggests that altering myosin-II activity in the cytoplasm of cells can modulate the mobility of vesicles, providing a possible mechanism for cells to dynamically tune the cytoplasmic environment in space and time.
- Resource Type:
- Article
- Campus Tesim:
- Fullerton
- Department:
- Department of Physics
- Creator:
- Yang, Joshua
- Description:
- Background In response to the growing awareness and use of electronic nicotine delivery systems (ENDS), or e-cigarettes, the U.S. Food and Drug Administration asserted its regulatory authority over ENDS in May 2016. Federal, state, and local regulatory action on ENDS may have significant and unique impacts on specialty ENDS retailers, including tobacco and vape shops. The purpose of this study is to describe the commercial motivations of vape shops in minority communities as business entities whose financial interests and actions may be particularly impacted by regulation of ENDS. Methods Specialty tobacco and vape retail stores in three minority communities were identified through an online search and community canvassing. Key informant interviews were conducted with tobacco and vape shop owners or managers discussing the business interests and tactics of selling ENDS for their store. Interview data were coded and analyzed for major themes. Results Interviews with 18 tobacco shops and 9 vape shops were completed. Tobacco shops’ reasons for carrying e-cigarettes were business oriented, focused on maintaining their customer base. In comparison, vape shops opened because of the owner’s positive experiences with e-cigarettes and belief in the potential of e-cigarettes to help people quit or reduce smoking. Tobacco shops mainly see their customers as using e-cigarettes to quit smoking whereas vape shops reported their customers using e-cigarettes for more varied reasons. Tobacco shops are much more limited in their marketing than vape shops, which rely heavily on social media and experimentation with other forms of marketing. Conclusions Tobacco shops and vape shops differ in their rationale and approaches to the business of e-cigarettes. Vape shops engage in a wide range of activities that stabilize their financial interest and increase their influence with customers and within the vape community. In order for regulatory policymaking and tobacco control interventions to maximize effectiveness, the actions of vape shops in promoting ENDS use and influencing policy debates must be taken into account.
- Resource Type:
- Article
- Campus Tesim:
- Fullerton
- Department:
- Department of Public Health