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Hydrogen Fuel Cell Drones Against Battery Drones: Last Mile Delivery Perspective
No full textHydrogen fuel cells are an abundant and cleaner source of energy, making them an attractive option for powering transportation systems. Hydrogen fuel cell drones are a new type of drone that generates energy from fuel cells for flight and expels heat and water vapor as byproducts. Compared to battery-powered drones, hydrogen fuel cell drones have better endurance and payload capacity due to their higher energy density, making them more efficient for eCommerce delivery. This research compares the performance of hydrogen and battery delivery drones for both droneonly and truck-drone last-mile delivery systems. A mixed integer programming model has been formulated to minimize the total delivery time for small to medium customer instances using the two-echelon vehicle routing problem, where drones are launched from the truck to serve one or more customers. The study conducted a comparative analysis by varying different parameters of drones on multiple sets of customer instances from real-world data to determine the best choice of drones for different scenarios. The results of the analysis show that hydrogen fuel cell drones have significant delivery advantages over typical battery drones in terms of delivery time and efficiency. Additionally, a sensitivity analysis was conducted to demonstrate the impacts of different parameters on the objective function of the delivery systems
The Role of Emotional Contagion in Risk Communication
No full textHistorically, emotional contagion has been studied in a series of contexts, however, there is little to no research on how contagion impacts risk perceptions. This study attempted to bridge the gap between emotional contagion and risk perceptions, specifically focusing on amplification from the Social Amplification of Risk Framework (SARF). To test these potential relationships, I conducted a 2 × 3 experiment that tested the effects of emotional expressions (fear) and media richness on emotional contagion as well as effects on risk perceptions and sharing intentions. In addition, the effects of individual differences such as expressiveness, susceptibility, and individualistic/collectivistic cultural tendencies were examined. Results found no support for the occurrence of emotional contagion, although there were changes in negative emotions between the pretest and posttest which can be attributed to the description of the risk event used as stimulus (i.e., chemical leak). Effects between changes in negative emotions and risk perceptions emerged. In addition, findings show that collectivism and susceptibility also predicted changes in negative emotions. These findings suggest that multiple processes determine if and when people experience emotional change in response to risk events
Three Essays of Healthcare Data-driven Predictive Modeling
No full textPredictive modeling in healthcare involves the development of data-driven and computational models which can predict what will happen, be it for a single individual or for an entire system. The adoption of predictive models can guide various stakeholders’ decision making in the healthcare sector, and consequently improve individual outcomes and the cost-effectiveness of care. With the rapid development in healthcare of big data and the Internet of Things technologies, research in healthcare decision-making has grown in both importance and complexity. One of the complexities facing those who would build predictive models is heterogeneity of patient populations, clinical practices, and intervention outcomes, as well as from diverse health systems. There are many sub-domains in healthcare for which predictive modeling is useful such as disease risk modeling, clinical intelligence, pharmacovigilance, precision medicine, hospitalization process optimization, digital health, and preventive care. In my dissertation, I focus on predictive modeling for applications that fit into three broad and important domains of healthcare, namely clinical practice, public health, and healthcare system. In this dissertation, I present three papers that present a collection of predictive modeling studies to address the challenge of modeling heterogeneity in health care. The first paper presents a decision-tree model to address clinicians’ need to decide among various liver cirrhosis diagnosis strategies. The second paper presents a micro-simulation model to assess the impact on cardiovascular disease (CVD) to help decision makers at government agencies develop cost-effective food policies to prevent cardiovascular diseases, a public-health domain application. The third paper compares a set of data-driven prediction models, the best performing of which is paired together with interpretable machine learning to facilitate the coordination of optimization for hospital-discharged patients choosing skilled nursing facilities. This collection of studies addresses important modeling challenges in specific healthcare domains, and also broadly contribute to research in medical decision-making, public health policy and healthcare systems
The Biological Consequences of Cryptic Local Adaptation and Contemporary Evolution
No full textEvolution is the foundation for all of biology. However, our approaches and understanding of evolution—simply, the change of allele frequencies from one generation to the next—have themselves evolved over time. In this dissertation I explore multiple approaches to understand evolution and the consequences of evolution across variable scales and study organisms. First, I use meta-analytic techniques and Bayesian hierarchical models to investigate the phenotypic consequences of two forms of cryptic local adaptation, co- and countergradient variation, by leveraging a decades-old quantitative genetics approach (Chapter 1). I find large effects for both co- and countergradient variation, however they are obscured in natural settings by concurrent large environmental effects. I also show that these large effects are ubiquitous across phenotypic traits, organisms, and environmental gradients, suggesting that while similar phenotypes may be the evolutionary end point, the mechanisms to achieve those phenotypes likely vary. In the following chapter I explore the rapid evolution of a unique and understudied species introduction, pink salmon (Oncorhynchus gorbuscha) in the Great Lakes. Pink salmon were introduced into Lake Superior in a single introduction event and have broken two obligate life histories, anadromy (though they treat the Great Lakes like surrogate oceans) and their fixed two-year life cycle, making them ripe subjects for contemporary evolution. Using whole-genome sequence data, I first investigate the effects of a genetic drift in the form of a bottleneck at introduction and characterize the subsequent loss of genetic diversity (Chapter 2). I show that despite a large loss of genetic diversity, pink salmon also rapidly adapted to their novel environment based on signals of putative selection across numerous regions of the genome, particularly in a period gene associated with their daily circadian clock (per2). Next, I explore how genome structure likely aided adaptation by pink salmon to the Great Lakes, providing evidence that a supergene (~29 Mbp) containing an inversion on chromosome 10 swept to near fixation in the Great Lakes (Chapter 3) and likely aided in osmoregulatory adaptation to this novel environment. Finally, I end with a short perspective chapter (Chapter 4) where I highlight potential future research directions for each of the previous chapters. Together, this research investigates the drivers and consequences of evolution across multiple scales and shows the powerful effect of genetic drift and genetic adaptation in shaping the genomic and phenotypic attributes of populations
Investigation of the Effects of Beta-Casein Protein Variants on Lactose Maldigestion
No full textBackground information: Lactose is a disaccharide found in milk and milk products. Lactose is digested by the enzyme lactase. Lactase non-persistence is a genetic trait in which individuals have low lactase activity. Approximately 70 percent of the world population is lactase non-persistent. It is a major cause of lactose maldigestion. An increase of 20 ppm hydrogen in breath within six hours of a lactose challenge dose (0.5 g of lactose per kg bodyweight) indicates lactose maldigestion. On the other hand, lactose intolerant individuals experience abdominal pain, bloating, diarrhea, and flatulence on consuming dairy. Therefore, lactose intolerant individuals avoid milk, which is a rich source of calcium. Consequently, lactose intolerance has been associated with reduced calcium intake and low bone mineral density. There are two mechanisms for lactose intolerance. The first mechanism is dependent on lactose dose and the second one is independent of lactose. Recently, A1 and A2 β-caseins have been associated with lactose intolerance. Studies conducted in China, New Zealand and Australia demonstrated fewer symptoms on consumption of milk containing only A2 β-casein as compared to milk containing both A1 and A2 β-casein. However, no study was conducted in the population residing in United States, where crossbred cows producing milk containing both A1 and A2 β-casein is the norm. Moreover, no study compared tolerance and digestion on consuming milk with different proportions of A1 and A2 β-casein. Lactose intolerant individuals can include A2 milk in their diet to meet the calcium requirement, if milk containing only A2 β-casein causes fewer symptoms and less maldigestion.Objectives: 1. To determine if a single meal of A2 milk containing only A2 β-casein would be better tolerated, producing fewer GI symptoms and less maldigestion, than conventional milk containing 75 percent A1 β-casein and 25 percent A2 β-casein2. To determine if a single meal of Jersey milk containing 25 percent A1 β-casein and 75 percent A2 β-casein would produce less maldigestion and intolerance, than conventional milk containing 75 percent A1 β-casein and 25 percent A2 β-casein3. To determine if the gastric emptying time of milk containing only A2 β-casein and milk containing 75 percent A1 β-casein and 25 percent A2 β-casein was different4. To determine if inflammation, maldigestion and intolerance is lower with a two-week daily consumption of milk containing only A2 β-casein as compared to milk containing 75 percent A1 β-casein and 25 percent A2 β-caseinMethods: Three randomized, double-blinded, crossover trials were conducted. The first study was conducted to determine tolerance and digestion of milk containing different proportions of A1 βcasein and A2 β-casein in subjects residing in the United States. There were four milk interventions in the study: A2 milk (milk containing 100% A2 β-casein), Jersey milk (milk containing 25%/75% A1/A2 β-casein), conventional milk (milk containing 75%/25% A1/A2 β-casein) and lactose-free milk (milk containing 60%/40% A1/A2 β-casein). Lactose intolerance in subjects was determined using a Qualifying Lactose Challenge Symptom Score after a challenge milk dose of 0.5 g of lactose/kg bodyweight. Subjects were screened for lactose maldigestion with a six-hour Hydrogen Breath Test
The Bachelorettes Dare
No full textA crazy dare on her bachelorette trip leads Gemma straight into the arms of Terrell Chase. He is everything her fiancé is not, tall, dark, and handsome, but also sweet, and surprisingly romantic. He quickly wins over her friends within minutes of meeting them, and the next thing she knows they are shoving her off on a date with him. Determined to walk down the aisle to her high school sweetheart Jake, in only a few short weeks, Gemma decides to treat dinner like a business meeting. But business meetings don’t typically end up with you naked in a stranger\u27s bed. Gemma came to New York expecting a week of relaxation and sightseeing, but her wild best friend Olive, wanted crazy and that is exactly what she got. Now Gemma is torn between the intense feelings she is feeling for Terrell after only one night and the feelings she thinks she feels for Jake. One night is all it takes for Gemma to question everything she thought she wanted. Is being together eight years, and growing up together enough anymore? Or was a one-night stand a sign that a life with Jake might not be everything she wants
Faculty perceptions and practices of information literacy training at Andrews University
Get PDFAndrews University’s students are equipped to demonstrate competence in eight life-long skills throughout their program curricula, including Information literacy. Therefore, James White Library strives to promote the importance and value of information literacy within the university’s community. Faculty have the most contact with students and the most direct curriculum oversight. One of the librarians’ primary objectives is to partner in offering opportunities for students to acquire skills to become lifelong information-literate citizens and broaden their training to prepare for twenty-first-century careers and lifelong learning. This research aims to identify AU faculty’s perceptions, understanding, and practice of IL training and its importance and impact on academic success. It is expected that the results of this research will provide librarians at AU with data to refine James White Library’s IL programs to serve students’ academic needs better and to prompt faculty to reflect on collaborative alternatives with librarians in information literacy instruction (ILI). A 5-part questionnaire was developed to collect the information needed for this quantitative-qualitative non-experimental design research. Items were selected based on a literature review of other relevant studies. They were customized to fit the actual function and setting of the library as it provides information literacy training to students. The questionnaire was sent through a Class Climate platform to the 623 Andrews University faculty members. Sixty-eight (10.9%) of the total population returned the survey. The value of ILT is increasingly recognized as essential to academic, workplace, lifelong learning, and student success, thus ensuring the development of capable citizens
PhD supervisors bad rap of Open Access Journals
Get PDFA decade or more preceded the formal coinage of the term open access, but the practice of making journal papers freely available online is a relatively new development. Among the first public statements to use the term open access, the Budapest Open Access Initiative, Bethesda Statement on Open Access Publishing, and Berlin Declaration on Open Access to Knowledge in the Sciences and Humanities were released in February 2002, and their initial concept of open access refers to unrestricted online access to scholarly research, primarily journal articles. Over the past few years, the number of journals available through open access has increased from 27.9% to 53.7%; currently, 830 journals are indexed in DOAJ, which represents a growth rate of about 51.46 % per year. It should be noted, however, that most of the indexed journals do not rank among the most prestigious. Scopus or WOS indexing these journals does not make any difference. Several PhD supervisors discourage their students from citing open access authors because they are concerned that it will lower the quality of their research. The impact factor of open access journals is low, which supports the argument for not referencing them. There is a growing chasm between academic faculties and libraries because supervisors do not see how free access benefits everyone. The open access model also saves libraries money by reducing the cost of journal subscriptions. Doctoral candidates, however, have difficulty citing highly reputable authors because many faculty members believe that open-access publications are of poor quality. As alleged in this article, libraries do not adequately educate faculty members about open access publishing, which assesses the quality of open-access journals using Q1 and Q2 standards
Who Is the Good Boy/Girl? Perspectives of French Handlers in AAI on the Selection of Their Dogs
Get PDFAnimal-assisted interventions (AAI) are well implemented in various health care settings; however, there is little data on the characteristics of the mediation dogs and their selection, which can influence the well-being of both the dogs and the beneficiaries. This study aims to gain a better understanding of the characteristics of French mediation dogs and the context in which they are selected to guide future research working on behavioral criteria for mediation dogs and help provide a basis for better selection of dogs in the field. To this end, we interviewed 111 French handlers in AAI, who work with at least one dog, through an online questionnaire about their professional backgrounds, the characteristics of their mediation dogs, and their views of the favorable and prohibitive criteria for a mediation dog. We also examined handlers’ representations of the context of selection of their mediation dog(s). Our data highlighted that (1) mediation dogs do not represent a homogeneous category regarding the age they started to work in AAI, their current ages, their certifications, and their breeds; and that (2) this may be related to the fact that the process of selecting mediation dogs includes the variability of the therapeutic settings as well as the professional backgrounds of the handlers and their personal affinities for a type of dog. There was also variability in handlers’ representations of the favorable and prohibitive criteria for the mediation dogs but with a convergence toward a sociable dog with self-control. The selection of mediation dogs in France requires an individual choice that considers each human–dog team in their relationship and in the context of their work
One Small Step for a Writing Center: Adapting to Reimagined Spaces
Get PDFDue to innovations in higher education, writing centers are increasingly moving away from the stereotypical, make-shift classroom to a variety of innovative spaces. This presentation uses the stories and voices of the tutors whose experience and development are affected by space to acknowledge the dynamic shift many writing centers are undergoing. Within the context of one-to-one peer tutorials in spaces not owned by any individual campus unit, this presentation provides considerations to increase understanding of how these new spaces shape tutors’ interactions with people and the space itself