Automated Segmentation of Cells with IHC Membrane Staining

This study presents a fully automated membrane segmentation technique for immunohistochemical tissue images with membrane staining, which is a critical task in computerized immunohistochemistry (IHC). Membrane segmentation is particularly tricky in immunohistochemical tissue images because the cellular membranes are visible only in the stained tracts of the cell, while the unstained tracts are not visible. Our automated method provides accurate segmentation of the cellular membranes in the stained tracts and reconstructs the approximate location of the unstained tracts using nuclear membranes as a spatial reference. Accurate cell-by-cell membrane segmentation allows per cell morphological analysis and quantification of the target membrane proteins that is fundamental in several medical applications such as cancer characterization and classification, personalized therapy design, and for any other applications requiring cell morphology characterization. Experimental results on real datasets from different anatomical locations demonstrate the wide applicability and high accuracy of our approach in the context of IHC analysi

Investigation to optimize the passive shock wave-boundary layer control for supercritical airfoil drag reduction

The optimization of passive shock wave/boundary layer control for supercritical airfoil drag reduction was investigated in a 3 in. x 15.4 in. Transonic Blowdown Wind Tunnel. A 14% thick supercritical airfoil was tested with 0%, 1.42% and 2.8% porosities at Mach numbers of .70 to .83. The 1.42% case incorporated a linear increase in porosity with the flow direction while the 2.8% case was uniform porosity. The static pressure distributions over the airfoil, the wake impact pressure data for determining the profile drag, and the Schlieren photographs for porous surface airfoils are presented and compared with the results for solid-surface airfoils. While the results show that linear 1.42% porosity actually led to a slight increase in drag it was found that the uniform 2.8% porosity can lead to a drag reduction of 46% at M = .81

Producing the Global Classroom: Exploring the Impact of US Study Abroad on Host Communities in San Jose, Costa Rica and Florence, Italy

This project draws attention to a disconnect between US higher education internationalization policy rhetoric which centers ideas of mutual cross-cultural exchange, and study abroad research, which focuses almost exclusively on the educational and experiential outcomes of the US based participant. Using neoliberalism as a theoretical framework, this comparative case study utilizes qualitative interviews with 57 host community members in the popular study abroad destinations of San Jose, Costa Rica and Florence, Italy, to focus on how those who engage with US study abroad students understand and are impacted by those encounters. Each descriptive case explores: a) what motivates locals to engage with US students; b) their modes of educative engagement; c) instances of harmony and dissonance that result; d) how they make meaning of these encounters; e) and what they see as outcomes of US study abroad in the community. Across these two diverse cases the findings suggest that many hosts perceive US students’ aversion to linguistic (and cultural) immersion as a lack of respect for hosts; the presence of US students contributes to foreign (US) imperialism; and that study abroad program design choices have an impact on the study abroad host experience

Vector-spread monomial ideals and Eliahou-Kervaire type resolutions

We introduce the class of vector-spread monomial ideals. This notion generalizes that of $t$-spread ideals introduced by Ene, Herzog and Qureshi. In particular, we focus on vector-spread strongly stable ideals, we compute their Koszul cycles and describe their minimal free resolution. As a consequence the graded Betti numbers and the Poincar\'e series are determined. Finally, we consider a generalization of algebraic shifting theory for such a class of ideals.Comment: This is the final version of my paper accepted for publication in the Journal of Algebr

The Effect of Freeze-thaw Events on DNA integrity in the Gray Treefrog (Hyla versicolor)

Freeze-tolerant gray treefrogs survive winter by producing natural cryoprotectants and accommodating ice formation within extracellular spaces. While frozen, gray treefrogs endure hyperglycemia, dehydration, and anoxia due to the halt of all bodily functions. Upon thawing, the frogs’ anoxic cells receive a rapid influx of oxygen, which can cause oxidative damage to vital macromolecules including DNA. Previous studies have suggested freeze-tolerant frogs avoid oxidative damage after freeze-thaw events by elevating antioxidant activity, but recent work has shown upregulated DNA repair encoding genes in post-freeze frogs. The objective of this thesis is to assess the cellular costs of freezing by measuring oxidative DNA damage in gray treefrogs (Hyla versicolor) as they thaw. Experimental frogs were frozen for 24 hours at -3°C and dissected after 2, 6, or 24 hours of thawing. Both liver and skeletal muscle tissues were excised and examined due to previously reported differences in antioxidant and cryoprotectant capacity. An ELISA was used to detect concentrations of oxidatively damaged guanine in each tissue sample. It was found that oxidative DNA damage within liver tissue did not increase from baseline during the freeze-thaw event. In muscle tissue, damaged DNA concentrations were elevated after 2 hours of thawing but slowly decreased with time. By 24 hours post-freeze, damage levels in muscle tissue returned to baseline, suggesting a full recovery. The absence of freezing-induced damage in the liver and short-lasting damage in the muscle shows that gray treefrogs are well adapted to mitigate freeze-thaw injury. These results reaffirm that freeze-tolerance is an effective overwintering strategy that is comprised of a complex series of evolutionary adaptations, which deserve further investigation

Homological Shift Ideals: Macaulay2 Package

We introduce the Macaulay2 package HomologicalShiftIdeals. It allows to compute the homological shift ideals of a monomial ideal, and to check the homological shift properties, including having linear resolution, having linear quotients, or being polymatroidal. The theory behind these concepts is explained and the main features of the package are presented

Exercise Oncology: the value of exercise among cancer patients and survivors

The World Health Organization reported increases in cancer incidence and considers this disease a health concern, as it represents a threat to life expectancy increase. Therapies and cancer side effects are positively impacted by exercise interventions. Research investigating exercise effects on cancer symptoms and therapies’ side effects or cancer survival has been classified as “Exercise Oncology”. The benefits of exercise have been largely demonstrated for common cancer types, and guidelines have been produced by several healthcare and exercise science institutions. The American College of Sports Medicine suggests a minimum of three times/week (30 min/session) of moderate aerobic training together with 2 sessions/week of resistance training (8–15 repetitions at 60% of 1-Repetition Maximum) for all cancer survivors. The same institution also emphasizes the need to individualize exercise interventions to cancer types and treatment highlighting the need to investigate more. For this reason, this thesis focuses on exercise oncology studies. Chapter II will summarize studies not directly including cancer patients but exploring potential relevant outcomes or interventions for this population. Two original investigations are here reported proposing the assessment of an easy-to-administer cardiovascular health test and the implementation of a manual therapy that can replace classic stretching interventions. In the same chapter a narrative review assessing the influence of different exercise types on tissue stiffness, a parameter which can be related to cancer onset and symptoms. Chapter III summarizes exercise oncology studies carried out during the PhD course. A total of 5 studies are presented involving breast (2) lung (1) or mixed cancer patients and survivors (2). A review and an original investigation have been proposed for breast cancer. A systematic review only is reported for lung cancer patients and survivors. Two more investigations have been summarized within this chapter, targeting samples with mixed cancer diagnoses, of which one is also a systematic review and one is an original investigation. The review target resistance training benefits on sleep variables. In conclusion, the studies shown in this thesis provided promising results highlighting the benefits of exercise intervention in the cancer population on a wide variety of outcomes. Interestingly, resistance training seems to be valuable in improving physical fitness variables and sleep quality. The field of exercise oncology should still advance on less studied cancer types and outcomes to provide exhaustive guidelines for clinical operators and exercise specialists