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Application of Correlation Pre-Filtering Neural Network to DNA Methylation Data: Biological Aging Prediction
No full textWe introduce the CPFNN (Correlation Pre-Filtering Neural Network) for biological age prediction based on blood DNA methylation data. The model is built on 20,000 top correlated DNA methylation features and trained by 1810 healthy samples from GEO database. The input data format and the instructions for parser and CPFNN model are detailed in this chapter. Followed by two potential uses, age acceleration detection and unknown age prediction are discussed
Duration and Intensity of End-Permian Marine Anoxia
No full textOcean anoxia was an important kill mechanism in the end-Permian mass extinction and uranium isotope data are among the most powerful tools for quantifying the global extent and duration of ocean deoxygenation due to the dependence of uranium isotope fractionation on bottom-water redox conditions. Although coherent stratigraphic variation in uranium isotope ratios (δ238U) and uranium concentrations ([U]) indicative of prolonged deoxygenation beginning coincident with the extinction is well established, the precise extent of anoxia and associated uncertainty have yet to be quantified. Uncertainty arises from both noise in the data and imprecise knowledge of key parameters within the uranium cycle. In this study, we use the Monte Carlo method to explore a range of scenarios and their implications for the uranium cycle across the Permian-Triassic boundary and through the first 1.7 million years of the Triassic. We then compare model predictions against measured data using principal component analysis to identify model runs and associated parameter values most compatible with trends in the observed data. The best-fitting models indicate a pronounced increase in the extent of seafloor anoxia across the Permian/Triassic transition, reaching 18% of the seafloor (95% CI: [11%, 47%]), lasting anywhere from 20 kyr to 1.2 Myr. There is an inverse relationship between the extent and duration of anoxia in the set of best-fitting models. This initial pulse of pronounced anoxia is followed by a prolonged aftermath, which continues through the remainder of the study interval, of less extensive, yet still expanded, anoxia covering 7.8% of the seafloor (95% CI: [1.6%, 48.9%]). Both expanded and protracted anoxia are required to fit existing data, with no indication of full re-oxygenation during the study interval
Myelin Characteristics of the Corpus Callosum in Capuchin Monkeys (\u3cem\u3eSapajus\u3c/em\u3e [\u3cem\u3eCebus\u3c/em\u3e] \u3cem\u3eapella\u3c/em\u3e) Across the Lifespan
Get PDFThe midsagittal area of the corpus callosum (CC) is frequently studied in relation to brain development, connectivity, and function. Here we quantify myelin characteristics from electron microscopy to understand more fully differential patterns of white matter development occurring within the CC. We subdivided midsagittal regions of the CC into: I—rostrum and genu, II—rostral body, III—anterior midbody, IV—posterior midbody, and V—isthmus and splenium. The sample represented capuchin monkeys ranging in age from 2 weeks to 35 years (Sapajus [Cebus] apella, n = 8). Measurements of myelin thickness, myelin fraction, and g-ratio were obtained in a systematic random fashion. We hypothesized there would be a period of rapid myelin growth within the CC in early development. Using a locally weighted regression analysis (LOESS), we found regional differences in myelin characteristics, with posterior regions showing more rapid increases in myelin thickness and sharper decreases in g-ratio in early development. The most anterior region showed the most sustained growth in myelin thickness. For all regions over the lifespan, myelin fraction increased, plateaued, and decreased. These results suggest differential patterns of nonlinear myelin growth occur early in development and well into adulthood in the CC of capuchin monkeys
Final Report on Humidification-Dehumidification Desalination Prototype
Get PDFFreshwater available across the globe is decreasing daily due to population growth, climate change, and pollution. The growing scarcity of freshwater affects more than a billion people worldwide and has prompted increased research into desalination processes. Large desalination plants are already in operation but are very expensive to build. Not every community has the means to implement these large systems, advancing the need for smaller, more economical, and efficient desalination plants.
The Desalinators researched and designed a humidification-dehumidification (HDH) desalination prototype that will convert saline water into potable water at a household scale (approximately 5-10 gal/day of freshwater). The sponsor, SwRI, intends to use the results of this project to further their research into the applications and improvements of small-scale HDH processes. Therefore, the prototype need not be perfect as long as it produces results that can be measured and analyzed.
The prototype features four main subsystems: primary heater, air circulation system, humidifier, and condenser. After the team’s extensive research, the final prototype was built using a water heater provided by the sponsor, an air pump (for forced convection) provided by the University, a packed bed tower humidifier with Raschig rings, and an ice bath within a plastic bucket with an air separator for the condenser. A schematic of the final prototype can be found in the figure section of the appendix. The team chose these components to maximize the performance of the prototype while minimizing costs.
The six project requirements included the following: the prototype shall use the HDH process to desalinate saline water into potable water; the prototype should operate within ±20% error of design parameters, including operating temperature, humidity at inlet and outlet, and outlet salt content; the prototype shall allow the operating temperature, humidity at inlet and outlet, and outlet salt content to be measured; the prototype should allow efficiency to be measured and compared to current desalination processes via gained-output ratio (GOR), recovery ratio (RR), or other efficiency measures; the prototype should allow outlet water samples to be collected and tested by instruments provided by SwRI; and the prototype may produce between 5-10 gallons/day.
To meet these requirements, several “complete prototype tests” were conducted in which temperatures, flow rates, humidity, and salinities were measured at 3-minute intervals during a 21-30 minute test. The complete prototype tests were conducted at a variety of water heater setpoints and flow rates. An additional “long test” was conducted as well where the same values were measured but for 100 minutes at 4-minute intervals. Using the results of these tests, the team was able to show that the prototype successfully met all but the last project requirement regarding potable water output volume and selecting optimal operating conditions. The potable water volume production rate could be increased if the tubing used within the prototype was upgraded to better withstand moderate pressures as well as using larger water and air pumps to increase flow rates
Formula SAE
Get PDFThe Formula SAE senior design project was truly unique. This project had been a 5 year long process to design, build, and test a raceable car. The car was this team\u27s prototype. While the original plan for the team was to develop an energy recovery system (ERS), this scope was altered because of the state of the car the team was left with. Upon examination, the car needed a lot of work before it was even going to start. Therefore, without a running car, there was no way of appropriately testing an ERS. Furthermore, had we developed a prototype for the ERS, there would have been no way to truly implement the design. It would only have stood as a proof of concept. Ultimately, the work required to start the car and develop and ERS would be a task that required two teams.
By making the change in scope, the team had been the closest to date to achieving a running car. Currently the car does not start. However, the team was able to get the engine to backfire in an attempt to get it to start. To get the full state, the issue has been identified as the engine control unit\u27s (ECU) inability to get an accurate camshaft sensor reading. With a hardware adjustment, the team was recently able to deliver a reading to the ECU. It outputs a correct square wave, but its periodicity has yet to be tested. The team has left to test the new hardware with the engine. In order to get to the point where the car is in position to start, many major subsystems required re-working. These systems include the wiring of the car, the fuel injection system, and the engine control unit (ECU). First, upon receiving the car, its wiring was incomplete, and very unorganized. This was no easy feat to correct. Furthermore, wiring of the car was particularly challenging because the team had to develop its own wiring schematic that combined the wiring schematics of the 2007 Phazer snowmobile engine and the schematic of the MegaSquirt II ECU. Additionally, the team had to include adjustments to the schematic that included the primary master switch (Required by FSAE rule IC.9.3) and cockpit main switch (Required by FSAE rule IC.9.4). Next, the fuel injection system was not correct. The fuel system that the original snowmobile used was an in-tank fuel system. However, the car requires an in-line fuel system. The differentiation between these two fuel systems was critical because they each require different types of fuel pumps. The state of this subsystem when the team received the car was incorrect. While the set up was correct (an in-line fuel system), the pump used in the system was an in-tank pump. Additionally there was no fuel filter. The team was able to acquire the appropriate pump and a fuel filter for an in-line pump system and completely changed and corrected the fuel injection system. Lastly, the ECU was the most challenging of the subsystems to correct. The ECU acts as the brain of the car. It interprets the sensor readings all throughout the car and responds with signals so that the car can time itself appropriately, start, and turn-off when it needs to. The first step towards completing the ECU was to install its two daughter boards. These were vital because they help to interpret the certain sensors that are specific to the Phazer engine (i.e. the VR sensor). Next, programming the ECU was critical. While there was a code provided specifically for the Phazer engine, it required tweaking. All of the program installation and critiquing was done through TunerStudio. This was the most challenging of the major subsystems because it was the topic that the team had no prior experience working with. However, the team did extensive amounts of research and had many conversations with experts to understand how to best program and implement the ECU.
It is important to note that this report is written as the car currently sits. That being said, it does not start. However, there is still time for the team to get the car running. The final step towards doing this is to make sure the hardware adjustment carries over appropriately to the final trial start of the car. Once it does this, the engine will have no issue injecting the fuel, and igniting its sparks (both of which have been tested and work). With the current status of the car understood, it is important to note that all design constraints, and applicability codes and standards were met. While the team\u27s most pressing constraint was time and money, neither has put a hindrance on the team working on, and improving the condition of the car. The codes and standards that are most applicable to the team were those provided by the FSAE rule book. However, there were not many regulations that regard getting the car to start. As mentioned it was important to include the master switch and emergency shutoff switch in accordance with the code. However, not much else was required for the team to get the car to start. It will be important for future teams to dive deeper into these standards as they get closer to racing the car. Primarily for the safety of the driver, but also, by not following the rule book, the team will be disqualified. Additionally, it will be helpful for future teams to refer to the design manual produced by this year\u27s team. It will encompass what has been completed by the team and what is left to do to get the car competition ready. Overall, the team progressed greatly with the car and has high hopes for the future of the FSAE senior design project
Sharenting and the Extended Self: Self-Representation in Parents’ Instagram Presentations of Their Children
No full textThe sharenting practice, or the sharing of one’s parenting and children online, has become a popular topic of critical focus that decries it as an exploitative disregard for children’s privacy and rights. The practice is performed, however, by a population (i.e., parents) that is generally inclined to protect its children, raising the present research question of whether sharenting could be alternatively guided by self-presentational goals. Guided by the theoretical notion of the extended self, the present study qualitatively examines parents’ Instagram posts using constant comparative analysis to identify how parents self-present in their sharenting posts. The results identify three self-presentational categories that illustrate how parents’ social media posts that depict a parent–child relational identity may actually be intended representations of the parent’s self. Implications for theory are discussed, as well as practical implications for the appropriate management of parents’ identities in a manner that respects children’s rights and privacy
Ticuna Ceramics Amidst the Expansion of Illicit Coca: Rendering New Relations
Get PDFIn Ticuna communities across Amazonia, ceramics are useful objects employed for cooking and storage. Their practical importance, however, does not describe the extent of their significance. In the following article, we consider Ticuna ceramics and ceramic-making practices as a means of studying the changes set in motion by the transformation of Ticuna ancestral lands in Peru’s lowland Amazonian region into zones of illicit coca cultivation. Drawing on mixed-methods ethnographic research, including participant observation, interviews, and a participatory film project focused on ceramic production, we evaluate contemporary practices of ceramic-making within three Peruvian Ticuna communities in the context of these transformations, and the national government’s subsequent responses to the coca situation. Ceramics are a starting point to explore a complex web of relations as Ticuna communities intersect with both drug-trafficking operations and agents of the Peruvian state
Slaying is Hell: Essays on Trauma and Memory in the Whedonverse
No full textThe films, television shows, and graphic novel series that comprise the Whedonverse continually show that there is a high price to be paid for love, rebellion, heroism, anger, death, betrayal, friendship, and saving the world. This collection of essays reveals the ways in which the Whedonverse treats the trauma of ordinary life with similar gravitas as trauma created by the supernatural, illustrating how memories are lost, transformed, utilized, celebrated, revered, questioned, feared, and rebuffed within the storyworlds created by Joss Whedon and his collaborators. Through a variety of approaches and examinations, the essays in this book seek to understand how the themes of trauma, memory, and identity enrich one another in the Whedonverse and beyond. As the authors present different arguments and focus on various texts, the essays work to build a mosaic of the trauma found in beloved works like Buffy the Vampire Slayer, Angel, Dollhouse, and more. The book concludes with a meta-analysis that explores the allegations of various traumas made against Joss Whedon himself.https://digitalcommons.trinity.edu/mono/1187/thumbnail.jp
The Vanishing Tuition Quandary: A Responsibility Accounting Case Study
Get PDFHidden Gem University is evaluating the profitability of each of its degree programs. The MBA program is growing but the operating income on the performance report is negative, which makes the program a target for possible discontinuance in the interest of the financial health of the University. In this case, students will evaluate the given report and various costs allocated to the MBA program to prepare an updated performance report. Accounting concepts such as cost behavior, flexible budgets, and responsibility accounting are integrated into this case study to encourage students to critically think about how these concepts interconnect and apply in a real-world setting for strategic decision making