Taxonomic and functional plant diversity of the Santorini-Christiana island group (Aegean Sea, Greece)

This is the first attempt to analyse vascular plant diversity patterns regarding the seven vegetated islands of the Santorini archipelago (Aegean Sea, Greece) as a whole. Hitherto unpublished floristic records, combined with critical use of taxonomic and chorological information from previous and most recent literature, resulted in a total of 696 infrageneric taxa (species and subspecies) occurring in the area. Detailed qualitative and quantitative phytodiversity spectra per individual island are presented, and floristic dissimilarity (beta-diversity) between islands is considered. Spatial distribution of 28 chorological, ecological, vegetative and reproductive traits for each recorded taxon have been calculated in order to detect regional and fundamental patterns in functional biogeography beyond traditional species-based approaches, based on both taxonomic and functional components of diversity. Mediterranean species constitute the most abundant chorological element and therophytes the most abundant life-form element in the region. Surface area is the most influential variable contributing to species richness; very strong relationships in (1) species per area, (2) functional richness per area and (3) functional richness per species richness are revealed for the Santorini archipelago. Floristic cross-correlations revealed an overall high floristic heterogeneity among the individual islands. The phytodiversity assessment presented is undoubtedly of documentary value in consideration of expected future eruptive events in the area which may damage the plant cover at least on some of the involved islands to a yet unpredictable extent

The Benefits and Challenges of Rural Special Education Teachers: Improving Teacher Retention in Rural Districts

Per the U.S. Census Bureau (n.d.), a rural area is “any population, housing, or territory NOT in an urban area.” Specifically, a rural area is defined as the area of 5 to 25 miles from an urban area (Geverdt, 2015). Nationally, rural school districts represent nearly 20% of the student population in the United States, but limited attention is given to the unique needs of these areas by national policymakers (Johnson et al., 2018). Rural schools face multifaceted challenges that often impede educational opportunities and post-school outcomes of students, including those who receive special education services (Erickson et al., 2012; Test & Fowler, 2018). Recruiting and retaining qualified special education teachers is also a challenge in rural school districts (Bargerhuff et al., 2007; Berry et al., 2011; Horn, 2021; Mueller & Brewer, 2013). The shortage of highly qualified special education teachers in rural areas is reported to be as high as 35% (Brownell et al., 2005). Lack of financial or human resource capacity negatively contributes to students with disabilities\u27 education (Johnson et al., 2018). Therefore, professional development opportunities are essential in supporting and preparing teachers in geographically isolated areas. Despite the challenges, there are also positive aspects of working in rural areas that may contribute to teachers’ decision in being employed in rural districts.https://digitalcommons.odu.edu/gradposters2022_education/1003/thumbnail.jp

Bridging innate and adaptive immunity in cardiovascular disease

Cardiovascular disease is the leading cause of death and morbidity in the world. Myocardial infarction and stroke constitute the main manifestations of atherosclerosis that lead to the majority of cardiovascular events. Calcific aortic valve stenosis is the most common valve pathology. Atherosclerosis and aortic valve stenosis share common risk factors such as hypercholesterolemia. Lipid lowering treatment has ameliorated the incidence of fatal events; however, residual risk remains indicating the need to address the inflammatory component in cardiovascular disease. Many inflammatory mediators, such as cytokines and receptors have been implicated to play important role in the pathogenesis and the endpoints caused by an atherosclerotic plaque rupture. The role of pattern recognition receptors has been highlighted in several experimental studies. Both protective and detrimental effects have been described for the members of Tolllike receptor (TLR) family, a class of pattern recognition receptors. Several studies have focused on the role of the cell surface TLRs. The aim of the current thesis is to investigate the role of the intracellular pattern recognition receptor, TLR7. To gain information of the pathophysiological mechanisms that TLR7 is involved, both human cohorts of atherosclerosis and aortic valve stenosis as well as experimental models of atherosclerosis have been utilized. In Paper I, mRNA expression of TLR7 in human carotid plaques was associated with patients´ outcome. Patients that expressed higher levels of TLR7 in their removed plaque had fewer future adverse cardio- and cerebrovascular events. Macrophages and T cells were co-localized with TLR7 in carotid plaques. Furthermore, carotid plaque tissue responded with increased cytokine secretion upon ex vivo stimulation with a synthetic TLR7 ligand. Paper II showed TLR7 mRNA expression in calcified aortic valves. TLR7 mRNA was increased in calcified areas of the aortic valves compare to intermediate and healthy areas. In addition, TLR7 expression was associated with M2 macrophage markers in all parts of the aortic valve. Stimulation of calcified aortic valves ex vivo with a synthetic TLR7 ligand elicited cytokine response that was possibly derived directly or indirectly by macrophages. In Paper III, we investigated the in vivo effects of a synthetic TLR7 ligand in experimental atherosclerosis. Locally, treatment with the synthetic TLR7 ligand led to decrease in lesion size and changes in plaque composition. The lesions of the treated mice presented lesions with smaller necrotic core and fewer apoptotic cells compare to the control. The treatment had effect in the spleen, leading to marginal zone B and regulatory T cell expansion. In the plasma, we observed decrease in cholesterol levels and increase in IgM antibodies against oxidized lowdensity lipoprotein. The three studies presented in this thesis illustrate the protective role of TLR7 in atherosclerosis and aortic valve stenosis. TLR7 was expressed in both myeloid cells and lymphocytes indicating a role of the receptor in bridging innate and adaptive immune. The current results can encourage the investigation of TLR7 ligands as therapeutic intervention in cardiovascular disease

Effects of Bug-in-Ear Technology on Specific Praise Statements Given by Paraeducators to Transition-Age Students with Autism

This investigation experimentally evaluated the effects of eCoaching with Bug-in-Ear (BIE) technology on the use of contingent specific praise in three paraeducators working in a special education transition classroom. A trained special education teacher provided performance-based feedback in real-time as paraeducators worked one-on-one with transition-age students with autism spectrum disorder (ASD) and comorbid intellectual disability (ID). As such, we used a multiple baseline research design to evaluate the effects of the independent variable (i.e., eCoaching). Results indicated that eCoaching using BIE technology increased the use of contingent specific praise given by paraeducators as they worked one-on-one with students. Increased rates of specific praise were observed during the fading condition, and all three paraeducators sustained high rates of specific praise. Our study demonstrates the efficacy of providing performance-based feedback by means of eCoaching with BIE technology, and recommendations for research and practical application are offered.https://digitalcommons.odu.edu/gradposters2020_education/1001/thumbnail.jp

Study of the Numerical Diffusion in Computational Calculations

The numerical simulation of fluid flow and heat/mass-transfer phenomena requires the numerical solution of the Navier-Stokes and energy-conservation equations coupled with the continuity equation. Numerical or false diffusion is the phenomenon of inserting errors in the calculations that compromise the accuracy of the computational solution. The Taylor series analysis that reveals the truncation/discretization errors of the differential equations terms should not be termed as false diffusion. Numerical diffusion appears in multi-dimensional flows when the differencing scheme fails to account for the true direction of the flow. Numerical errors associated with false diffusion are investigated via two- and three-dimensional problems. A numerical scheme must satisfy necessary criteria for the successful solution of the convection-diffusion formulations. The common practice of approximating the diffusion terms via the central-difference approximation is satisfactory. Attention is directed to the convection terms since these approximations induce false diffusion. The equations of all the conservation equations in this study are discretized by the finite volume method

Mathematical Modeling of Aerodynamic Heating and Pressure Distribution on a 5-Inch Hemispherical Concave Nose in Supersonic Flow

During the design of an aircraft, a significant parameter that is taken into consideration is aerodynamic heating. Aerodynamically induced heating affects both the structure of the aircraft and its vulnerability to heat-seeking missiles in modern warfare. As a result, the ability to calculate efficiently the heating produced as well as the pressure distribution in such flows is crucial. Therefore, in this present study, the PHOENICS CFD code as modified by DRA Farnborough in order to calculate heat transfer and pressure measurement on a 5-inch hemispherical concave nose at a Mach number of 2.0 is evaluated and customized in order to produce faster and more accurate results. Apart from numerical alterations, different turbulence models are being examined as well as different discretization schemes. Numerical solutions show improvement up to 6% in comparison with the original model, both in terms of convergence rate and in terms of agreement with the available experimental data. With the new modeling suggested in the present work, the significance of both the discretization scheme and the choice of the turbulence modeling is demonstrated for the flows under consideration. The use of a high-order discretization scheme is suggested for more acute areas of the body modeled in order to improve results further

Immune Response in Ovarian Cancer: How Is the Immune System Involved in Prognosis and Therapy: Potential for Treatment Utilization

Ovarian cancer is one of the leading causes of cancer-related death among women. Resistance to the disease occurs in more than 70% of the cases even after treated with chemotherapy agents such as paclitaxel- and platinum-based agents. The immune system is increasingly becoming a target for intense research in order to study the host's immune response against ovarian cancer. T cell populations, including NK T cells and Tregs, and cytokines have been associated with disease outcome, indicating their increasing clinical significance, having been associated with prognosis and as markers of disease progress, respectively. Harnessing the immune system capacity in order to induce antitumor response remains a major challenge. This paper examines the recent developments in our understanding of the mechanisms of development of the immune response in ovarian cancer as well as its prognostic significance and the existing experience in clinical studies

A Novel Method for Calculating the Radiated Disturbance from Pantograph Arcing in High-speed Railway

Pantograph arcing is a key electromagnetic disturbance source to affect train control system in high-speed railway. Since the characteristics of pantograph arcing is related to train speed, it is necessary to investigate effective numerical modeling and measurement method. However, due to the uncontrollable train speed during on-site measurement, it is difficult to study the radiated disturbance from arcing in the corresponding speed and repeat the same measurement. Therefore, a method combined numerical modeling and reverberation chamber measurements for calculating the radiated disturbance from pantograph arcing in a high-speed railway is proposed. Numerical models of train and sensitive equipment are built to calculate the coupling coefficient in CONCEPT II. And a new measurement procedure in reverberation chamber using pulse signal as the reference source is proposed based on a speed-controllable laboratory replica to measure the total radiated power of pantograph arcing. Then the radiated disturbance from pantograph arcing to the sensitive equipment is achieved with the coupling coefficient and the total radiated power of arcing. The method is verified laboratory experiments. This method can solve the uncontrollable train speed problem during on-site measurement and improve the repeatability of measurement

Cerigo Speleogical Project. Ioannis Petrocheilos and Speleological Research in Kythera island, Greece, from 1930 to 1960.

This paper aims at presenting Ioannis Petrocheilos’ “works and days” and the speleological research on the island of Kythera, Greece, from 1930 to 1960. Ioannis Petrocheilos was born on Kythera and conducted the first speleological research in the area in the early 30’s. Within 20 years Petrocheilos explored and studied more than 20 caves on the island with a specific and precise methodology. All his notes and data from that period survived in the archives of the Hellenic Speleological Society. Within the framework of the Cerigo Speleological Project we studied the history and the chronicles of that period in order to shed light on the beginning of Greek Speleology