Experimental and Conceptual Approaches to Studying Bet Hedging in Microorganisms

Bet-hedging strategies are used by organisms to survive in

unpredictable environments. To pursue a bet-hedging strategy, an

organism must produce multiple phenotypes from a single genotype. What

molecular mechanisms allow this to happen? To address this question, I

created a synthetic system that displays bet-hedging behavior, and

developed a new technique called `TrackScar' to measure the fitness

and stress-resistance of individual cells. I found that bet-hedging

can be generated by actively sensing the environment, and that

bet-hedging strategies based on active sensing need not be

metabolically costly. These results suggest that to understand how

bet-hedging strategies are produced, microorganisms must be

examined in the actual environments that they come from.

Studying Recommender Systems to Enhance Distributed Computing Schedulers

Distributed Computing frameworks belong to a class of programming models that allow developers to

launch workloads on large clusters of machines. Due to the dramatic increase in the volume of

data gathered by ubiquitous computing devices, data analytic workloads have become a common

case among distributed computing applications, making Data Science an entire field of

Computer Science. We argue that Data Scientist's concern lays in three main components: a dataset,

a sequence of operations they wish to apply on this dataset, and some constraint they may have

related to their work (performances, QoS, budget, etc). However, it is actually extremely

difficult, without domain expertise, to perform data science. One need to select the right amount

and type of resources, pick up a framework, and configure it. Also, users are often running their

application in shared environments, ruled by schedulers expecting them to specify precisely their resource

needs. Inherent to the distributed and concurrent nature of the cited frameworks, monitoring and

profiling are hard, high dimensional problems that block users from making the right

configuration choices and determining the right amount of resources they need. Paradoxically, the

system is gathering a large amount of monitoring data at runtime, which remains unused.

In the ideal abstraction we envision for data scientists, the system is adaptive, able to exploit

monitoring data to learn about workloads, and process user requests into a tailored execution

context. In this work, we study different techniques that have been used to make steps toward

such system awareness, and explore a new way to do so by implementing machine learning

techniques to recommend a specific subset of system configurations for Apache Spark applications.

Furthermore, we present an in depth study of Apache Spark executors configuration, which highlight

the complexity in choosing the best one for a given workload.

Study Abroad Course Development: Pre-Departure Sessions

Study abroad is a highly encouraged component of the undergrad business program at Bella Lake University, with the large majority of undergraduate students choosing to study and live in a foreign country to expand on their international experiences. Currently, there is no learning structure or learning outcome expectation for students that will participate in the study abroad experience. This project focuses on the development of a course that supports students in the pre-departure phase of their study abroad journey and prepares them to set goals, understand the learning process and the practices of experiential learning to encourage students to achieve both personal and professional goals, and encourage the development of intercultural competence. The discourse surrounding the perceptions and efficacy of the course development is based on a self-assessment survey completed by 121 undergraduate business students that participated in the pre-departure sessions prior to leaving for study abroad in March 2016. The self-assessment results overall showed that the course achieved its aims with the majority of students rating that they were more likely to understand and engage in experiential learning, set goals for their study abroad experience and felt more prepared for study abroad after attending the pre-departure sessions. The project concludes that in order for the pre-departure course to maintain its value, the conversation with students surrounding experiential learning in study abroad needs to continue with further course development focusing on both during and post-study abroad. Further exploration can also be done to find varying ways to motivate different students to engage in the learning potential of study abroad.

Studying French-Origin Middle English Lexis Using the Bilingual Thesaurus of Medieval England: A Comparison of the Vocabulary of Two Occupational Domains

This paper investigates how far it is possible to assess the degree of penetration of French-origin lexis into Middle English by means of the structures and data of the Bilingual Thesaurus of Medieval England. It begins with an outline of the aim and scope of the project, describing some of the methodological decisions behind the creation of the Bilingual Thesaurus, such as the use of the Middle English Dictionary and the Anglo Norman Dictionary as sources. Some provisional findings relating to Middle English words of French-origin in the semantic domains of Manufacture, in particular the sub-domains of Metal-working and Woodworking, and Travel by Water are then presented.

An Ex Vivo Model for Studying Hepatic Schistosomiasis and the Effect of Released Protein from Dying Eggs

BACKGROUND: We report the use of an ex vivo precision cut liver slice (PCLS) mouse model for studying hepatic schistosomiasis. In this system, liver tissue is unfixed, unfrozen, and alive for maintenance in culture and subsequent molecular analysis.

METHODS AND FINDINGS: Using thick naive mouse liver tissue and sterile culture conditions, the addition of soluble egg antigen (SEA) derived from Schistosoma japonicum eggs, followed 4, 24 and 48 hrs time points. Tissue was collected for transcriptional analysis and supernatants collected to quantitate liver enzymes, cytokines and chemokines. No significant hepatotoxicity was demonstrated by supernatant liver enzymes due to the presence of SEA. A proinflammatory response was observed both at the transcriptional level and at the protein level by cytokine and chemokine bead assay. Key genes observed elevated transcription in response to the addition of SEA included: IL1-α and IL1-β, IL6, all associated with inflammation. The recruitment of antigen presenting cells was reflected in increases in transcription of CD40, CCL4 and CSF1. Indications of tissue remodeling were seen in elevated gene expression of various Matrix MetalloProteinases (MMP3, 9, 10, 13) and delayed increases in TIMP1. Collagen deposition was significantly reduced in the presence of SEA as shown in COL1A1 expression by qPCR after 24 hrs culture. Cytokine and chemokine analysis of the culture supernatants confirmed the elevation of proteins including IL6, CCL3, CCL4 and CXCL5.

CONCLUSIONS: This ex vivo model system for the synchronised delivery of parasite antigen to liver tissue provides an insight into the early phase of hepatic schistosomiasis, corresponding with the release of soluble proteins from dying schistosome eggs.

Using UAV acquired photography and structure from motion techniques for studying glacier landforms: application to the glacial flutes at Isfallsglaciären

Glacier and ice sheet retreat exposes freshly deglaciated terrain which often contains small-scale fragile geomorphological features which could provide insight into subglacial or submarginal processes. Subaerial exposure results in potentially rapid landscape modification or even disappearance of the minor–relief landforms as wind, weather, water and vegetation impacts on the newly exposed surface. Ongoing retreat of many ice masses means there is a growing opportunity to obtain high resolution geospatial data from glacier forelands to aid in the understanding of recent subglacial and submarginal processes. Here we used an unmanned aerial vehicle to capture close-range aerial photography of the foreland of Isfallsglaciären, a small polythermal glacier situated in Swedish Lapland. An orthophoto and a digital elevation model with ~2 cm horizontal resolution were created from this photography using structure from motion software. These geospatial data was used to create a geomorphological map of the foreland, documenting moraines, fans, channels and flutes. The unprecedented resolution of the data enabled us to derive morphological metrics (length, width and relief) of the smallest flutes, which is not possible with other data products normally used for glacial landform metrics mapping. The map and flute metrics compare well with previous studies, highlighting the potential of this technique for rapidly documenting glacier foreland geomorphology at an unprecedented scale and resolution. The vast majority of flutes were found to have an associated stoss-side boulder, with the remainder having a likely explanation for boulder absence (burial or erosion). Furthermore, the size of this boulder was found to strongly correlate with the width and relief of the lee-side flute. This is consistent with the lee-side cavity infill model of flute formation. Whether this model is applicable to all flutes, or multiple mechanisms are required, awaits further study.

A New Technique for Studying Vapour–liquid Equilibria of Multi-Component Systems

A Fourier transform infrared gas-phase method is described herein and capable of deriving the vapour pressure of each pure component of a poorly volatile mixture and determining the relative vapour phase composition for each system. The performance of the present method has been validated using two standards (naphthalene and ferrocene), and a Raoult’s plot surface of a ternary system is reported as proof-of-principle. This technique is ideal for studying solutions comprising two, three, or more organic compounds dissolved in ionic liquids as they have no measurable vapour pressures.

Literary Studies in the Border Zone : International Students Studying American Fiction in Dalarna

Det amerikanska subjektets rekonstruktion: en studie av prisbelönad amerikansk skönlitterär prosa från 1990-talet

Providing a Positive Learning Experience for International Students Studying at a UK University: a Literature Review

Much of the current literature relating to international students at university level tends to highlight their experiences from a deficit perspective and in some cases even problematises the experience for the student and university. Other studies tend to focus on recruitment and motivation rather than the lived experiences of the student, thereby providing little assistance to guide the student, academic and host university in their preparation for, and working with, the international student. International students choose to study in the United Kingdom for a variety of positive reasons. However, these factors have the potential to become stressors as the student makes the transition to studying in a foreign country. Rather than viewing these stressors from a negative perspective, this literature review identifies how, with planning, support and understanding, universities can provide and develop a positive experience for all concerned.

Resilience of small-scale societies’ livelihoods: a framework for studying the transition from food gathering to food production

The origins of agriculture and the shift from hunting and gathering to committed agriculture is regarded as one of the major transitions in human history. Archeologists and anthropologists have invested significant efforts in explaining the origins of agriculture. A period of gathering intensification and experimentation and pursuing a mixed economic strategy seems the most plausible explanation for the transition to agriculture and provides an approach to study a process in which several nonlinear processes may have played a role. However, the mechanisms underlying the transition to full agriculture are not completely clear. This is partly due to the nature of the archeological record, which registers a practice only once it has become clearly established. Thus, points of transitions have limited visibility and the mechanisms involved in the process are difficult to untangle. The complexity of such transitions also implies that shifts can be distinctively different in particular environments and under varying historical and social conditions. In this paper we discuss some of the elements involved in the transition to food production within the framework of resilience theory. We propose a theoretical conceptual model in which the resilience of livelihood strategies lies at the intersection of three spheres: the environmental, economical, and social domains. Transitions occur when the rate of change, in one or more of these domains, is so elevated or its magnitude so large that the livelihood system is unable to bounce back to its original state. In this situation, the system moves to an alternative stable state, from one livelihood strategy to another.

Concerns and Expectations of Students Participating in Study Abroad Programs: Blogging to Reveal the Dynamic Student Voice

Study abroad programmes (SAP) have become increasingly popular with university students and within academia. They are often seen as an experiential opportunity to expand student learning and development, including increases in global, international, and intercultural competences. However, despite the increasing popularity of and participation in study abroad programmes, many student concerns and uncertainties remain. This research investigates initial pre-departure concerns and apprehensions of students undertaking a one-semester study abroad programme and uses these as context for an examination of violated expectations of students during their programme. The research uses interpretative phenomenological analysis to interpret data collected from regularly-updated blogs composed by students throughout their SAP experience. The process of using blogs to collect data is less formalised than many other approaches of interpretative phenomenological analysis, enabling ‘in the moment’ feedback during the SAP and lending greater depth to the understanding of student perceptions.