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Effects of temperature on swimming performance of three Gila congenerics: G. cypha, G. elegans and G. robusta
Get PDFThe Colorado River Basin (CRB) is an environmentally complex aquatic network, with historically large annual variations in discharge, sediment loads, and water temperatures, that pose significant ecological and physiological challenges to its native ichthyofauna (Schmidt et al., 1998; Kammerer, 2005). Effects of climate change within the CRB are likely to produce a drier and warmer regional climate, more frequent droughts, as well as changes in variability, frequency, and amount of precipitation (Meehl et al., 2010; Xie et al, 2010; Pielke et al., 1999). Water temperatures within the CRB could increase by 5.6° C over the next century, which will affect the aquatic food web structure, biodiversity, and the endemic native fishes of this region, and it is uncertain how this ecosystem and its organisms will respond (Wrona et al., 2006; IPCC, 2007; Arismendi et al., 2014). Among the native species which will be affected by this water temperature increase, Gila elegans, G. cypha, and G. robusta offer a unique opportunity to examine how the swimming performance of these species will be affected by climate change due to their close phylogenetic relationships, shared ecology, and distinctive morphologies. (Minckley & Marsh, 2009). This study examined the effects of temperature on the swimming performance of juvenile G. elegans, G. cypha, and G. robusta acclimated to one test temperature (10°C, 16°C, 20°C, or 30°C) for 7 days. Results of this study demonstrated that these three species are affected uniformly by temperature, that temperature and species affects the swimming performance, and yet the results do not support an interaction of these two variables as having an effect of swimming performance. Of these three species, G. cypha demonstrated the greatest swimming performance while G. elegans and G. robusta demonstrated indistinguishable differences in swimming performance. The swimming performance for G. cypha increases as temperature is increased from 10°C to 20°C, however there is no difference between the swimming performance at 20°C and 30°C. Size, temperature, and the interaction of these two response variables was shown to influence the swimming performance of juvenile G. elegans
Exercise-induced telomerase gene expression is dependent on age and gender
Get PDFThe ability to repair cellular damage is reduced with aging, resulting in increased cellular senescence. Telomeres, the protective caps of the chromosome, shorten as cells divide but the rate of telomere attrition is regulated by two proteins: telomerase and shelterin. An increase in telomerase activity could slow down the rate of telomere shortening, while shelterin prevents telomere elongation by blocking telomerase. Acute exercise stimulates telomerase in young men, as measured by increased expression of telomerase reverse transcriptase (hTERT). The aim of the present study was to investigate age-related differences in telomerase and shelterin response to exercise. We hypothesized that acute exercise would stimulate an increase in telomerase activity without an increase in activity of shelterin in both young and older individuals and that the hTERT response would be attenuated with aging. Young (22 ±2y, n=11) and older (60 ±2y, n=8) men and women performed a 30-minute high intensity interval cycling exercise and blood was collected before and at 30, 60, and 90 minutes after exercise. Gene expression of hTERT and TRF2 (telomere repeat binding factor 2, a shelterin protein) were measured in peripheral blood mononuclear cells (PBMCs) as markers of telomerase and shelterin activity, respectively. Additionally, gene expression of interleukin-6 (IL- 6) was measured as a positive control of the exercise stimulus. The trial induced a significant hTERT response in the cohort as a whole (p<0.05) with a greater increase in the young as compared to the older group (time-by-age group interaction p<0.05). As expected TRF2 did not change in response to the trial, however older individuals had significantly higher TRF2 response at +60 min (p<0.05). There was a significant time-by-age group interaction for IL-6 gene expression (p=0.048). These data support our hypothesis that telomerase gene expression attenuates with age in response to high intensity exercise. Unexpectedly, there was a gender difference where men had significantly greater hTERT (p<0.05) and TRF2 (p<0.05) responses compared to women, regardless of age. The role of gender was a novel finding and should be explored in future research
Connecting Cline Library with tribal communities: A case study
Get PDFNorthern Arizona University (NAU) is a public state university with a commitment to Native American students (Hughes and Tsosie 2013). The university’s Cline Library strongly supports the values of academic excellence, student engagement, and student success. NAU is a unique academic institution because it has a Native student community population of 4%; according to the National Center for Educational Statistics, in 2006 Native students at US universities averaged only 1% of the entire student population. As of 2016, the Native American population at NAU was 825 students. Compared to the overall student population Native students comprise about 3% of student growth. In 2005 NAU’s strategic plan defined a commitment to Native Americans and to “become one of the nation’s leading universities serving Native Americans.” This goal is currently under revision by the university’s Commission for Native Americans and the Vice President for Native American Affairs (Chad Hamill, PhD). What does this goal mean for the university? This is the only goal in the university’s strategic plan where a specific community is mentioned and highlighted as a priority. The institution’s commitment to serving Native Americans has a direct impact on the recruitment, retention, and graduation rates for Native American students. The university commitment to developing collaborative services and outreach programs to Native American communities and promoting engagement and appreciation of Native American cultures and tribal nations within the university and broader community is still a top goal (NAU Strategic Plan 2005-2010). Today over a hundred tribes from across the country are represented at NAU. A large portion of students come from the geographic region of Northern Arizona and New Mexico. Beginning in 2008, Cline Library sought out ways in which it could align its activities with the university's strategic commitment to serving Native Americans. Cline librarians and archivists work to support indigenous students, researchers, scholars, and communities through collecting and preserving Indigenous scholarship. In order to achieve the university’s commitment to Native Americans Cline Library needs a robust collection and services available for Native students.
This paper will focus on themes that emerge from a critical analysis of the library’s collections and their work with American Indian communities. It will start by describing how the library applies concepts of critical librarianship and teaching and learning to collection development. The conversation continues with the critical role of librarians and archivists at Cline Library in supporting faculty and students. Finally, as an independent yet integrated department, the library’s Special Collections and Archives unit responds to the Native American community’s tribal concerns with the collaborative management of cultural materials in ways that balance archival theory and practice with access to sensitive information. The conclusion offers strategies to improve on existing efforts at Cline and ties together many of the themes woven throughout the article
Understanding how victim and advocates perceive and deliver services based on organizational structure and institutional location
No full textIn the United States, victim-witness services exemplify two opposing victim service models of how the state should best meet the needs of crime victims. The welfare model is focused on providing social services to victims separate from the criminal justice process, while the prosecutorial model seeks to increase victims’ participation within all aspects of the criminal justice system. In Northern Arizona, two counties have achieved one of these two agendas. Using a qualitative research approach, I found that both victim advocacy programs adhere to separate philosophy models; therefore, the core focus of the organization is different. Victim advocates deliver and perceive services in a diverse manner; this is contributed to the organizational structure and institutional location of the agency. Yavapai County Victim Services Division aligns with a prosecutorial model, while Victim Witness Services for Coconino County follows a welfare model. The implications of these differing models for advocates and victim service delivery are discussed
Creative Interventions to Increase Counselor-in-Training Wellness
Get PDFWellness is a broad term that emphasizes a person’s current state of mental, physical, emotional, spiritual, and professional wellness. Professional counseling was built upon the foundations of wellness and practitioner self-care. While counseling programs understand the importance of wellness and counseling ethics emphasize the necessity of professional wellness, students frequently do not feel prepared or trained enough in wellness dimensions. This manuscript provides a rationale for a program wellness model and outlines a proposed series of interventions aimed at increasing students’ understanding, ability to self-assess, and strategies related to self-care and wellness
Promoting the Wellness of Physician-Residents: Counselor-Delivered Coaching
Get PDFCurrent studies on coaching have largely been process- and outcomes-oriented while lacking a firm theoretical foundation on which to base skills and techniques. Coaching has been utilized in many settings in order to address employee work attitude and well-being. This article explores the effects of counselor-delivered coaching on the wellness of physician-residents. Counselors are trained in many of the skills that organically apply to coaching, and medical education programs can benefit from counselor-facilitated coaching as part of their graduate medical education program. Counselor-delivered coaching also can help residents reduce common stresses, mitigate negative patient outcomes, and avoid burnout. This increase in physician wellness is likely to result in decreased medical errors. For these reasons, the authors explore the use of basic counseling techniques in the context of coaching sessions involving medical school educators and residents, thereby bridging the gap between coaching and counseling. Counselor-delivered coaching may be a valuable resource for reducing physician burnout. Therefore, medical schools and medical practices should consider developing and including counselor-delivered coaching to improve physicians’ quality of life and thus, in turn, patient results. Findings from this study support future data-driven studies of counselor-delivered coaching, training opportunities for counselor education programs, and an evolution of coaching techniques
Examining the Effects of Model-Based Inquiry on Conceptual understanding and Engagement in Science
Get PDFModel-Based Inquiry (MBI) is an instructional model which engages students in the scientific practices of modeling, explanation, and argumentation while they work to construct explanations for natural phenomena. This instructional model has not been previously studied at the community college level. The purpose of this study is to better understand how MBI affects the development of community college students’ conceptual understanding of evolution and engagement in the practices of science. Mixed-methods were employed to collect quantitative and qualitative data through the multiple-choice Concepts Inventory of Natural Selection, student artifacts, and semi-structured interviews. Participants were enrolled in Biology Concepts, an introductory class for non-science majors, at a small, rural community college in the southwestern United States. Preliminary data shows that conceptual understanding is not adversely affected by the implementation of MBI, and that students gain valuable insights into the practices of science. Specifically, students who participated in the MBI intervention group gained a better understanding of the role of models in explaining and predicting phenomena and experienced feeling ownership of their ideas, an appropriate depth of thinking, more opportunities for collaboration, and coherence and context within the unit. Implications of this study will be of interest to postsecondary science educators and researchers who seek to reform and improve science education
Reclaiming seeds of resistance: amplifying narratives of reform in the U.S. food system
No full textThis thesis investigates how contemporary US food justice organizations challenge and attempt to transform the current US food and agriculture structure. In this study I contribute a theoretical framework rooted in social transformation theory and food regime analysis. Food regime scholarship tends to focus on the international political economy, concentrating on the relationship between global capital and global social movements. Thus, the role of state intervention at the national level and US-based social movements are currently under-theorized.In Part I of this thesis, I situate the development of US agriculture policy in the food regime literature, drawing on Polanyi’s concept of a double movement to illuminate a dialectical relationship between policies of marketization and social reform. Further, I explore the marketization and impact of immaterial labor, like green certifications and intellectual property rights, on contemporary social movements and the food system. In Part II, I examine the Institute for Agriculture and Trade Policy, Food First, and WhyHunger to explore how current organizations envision social change and the strategies they adopt to create transformation. In particular, I bring attention to the importance of interstitial strategies to contemporary US food justice organizations, while illuminating the tension between their vision and strategy for social change
Flow Behavior and Emplacement of the Northwest Dike Swarm in the Jagged Rocks Complex, Hopi Buttes Volcanic Field, Arizona
Get PDFThe Jagged Rocks Complex in the Hopi Buttes Volcanic Field provides excellent exposure of shallow dikes and sills as well as massifs and buds that fed three to five maar-diatreme volcanoes. The northwest dike swarm consists of a series of six en-echelon dikes as well as five massifs and many smaller buds. The excellent exposure of these shallow plumbing structures provides a unique opportunity to study the role of shallow dikes in supporting maar-diatreme eruptions.
Anisotropy of magnetic susceptibility (AMS) and other rock magnetic methods were used to investigate the timing of the intrusions, the characteristics of their magnetic mineralogy, and the flow history preserved within the dikes. Curie point analysis shows the magnetic minerals have a low Curie point indicative of high-titanium titanomagnetite. The isothermal remanent magnetization (IRM) measurements indicate that the grains are dominantly pseudo-single domain (PSD) edging on single domain (SD). This is supported by anisotropy of anhysteretic remanent magnetization (AARM) measurements, which also indicate the influence of SD grains on some sites’ anomalous AMS fabrics. AMS shows dominantly horizontal flow in the majority of the sites. Only half of the margin pairs provide reliable imbricated K1 lineations for flow direction interpretation. The use of the K3 method to define the main foliation plane does not reveal any imbricated fabrics beyond those seen with the K1 method.
The interpretable margin pairs all show flow to the northwest, providing flow directions for five out of the six dikes analyzed. This direction is generally away from the other main series of intrusions to the southeast, indicating a lateral diversion of magma away from a magma-supply system located somewhere to the southeast. The lateral intrusion of the northwest dike swarm could have been a response to overpressure in the shallow subsurface due to the formation of a volcanic edifice or due to overpressure in the magma supply system. Coherent dikes formed first, with limited water/magma interactions, and later reduction in flux or withdrawal of magma initiated the phreatomagmatism that formed the massifs
An investigation of the role of thermal conditions, hydrologic processes, and country-rock permeability in maar eruptions
Get PDFThe interaction of magma and groundwater often results in explosive eruptions due to processes of molten fuel-coolant interaction (MFCI). Explosivity of these eruptions is largely controlled by the extent of mixing between water (coolant) and magma (fuel) and the location in the conduit where interaction occurs. Recently published experiments and calculations show that most phreatomagmatic tuff-ring deposits are probably produced by explosions occurring above ~200 m depth, while those below this depth are rarely energetic enough to displace material at the ground surface. It is thus uncertain how phreatomagmatic eruptions occur where depth to the water table is far below this critical depth of 200 m, as it is in some semi-arid and arid environments. Even in locations where groundwater is above this depth, explosions using up available water can result in progressive drawdown of the water table, producing a cone of groundwater depression within the diatreme. In these cases, the question arises as to how explosions continue if the water source “dries up.” The idea of explosive transport, or water being thrown upward from explosions beneath the water table, has been described as one possible mechanism for providing shallow water for continued explosions; however, this process would not likely move the large quantities of water needed to sustain long-term phreatomagmatism. Few studies have focused on questions regarding the details of thermohydrologic processes that control these eruptions. To address this problem, I have investigated two maars, Colton Crater and Rattlesnake Crater, in the San Francisco Volcanic Field of northern Arizona. Hydrologic, structural, and stratigraphic data of the subsurface beneath each volcano have been used to construct conceptual models of groundwater flow and heat transfer within each eruptive system, and relevant thermophysical flow processes have been modeled using the TOUGH2 simulator.
Colton Crater was formed by a prolonged, dry cinder-cone-building eruption with only a brief late period of intense phreatomagmatic activity, while Rattlesnake Crater’s deposits display characteristics of sustained magma-water interaction and an eventual drying-out. The continued phreatomagmatic explosions at Rattlesnake Crater may have resulted from large-scale vapor transport, driven by magmatic heat, through permeable country rock and vertical fractures prior to and during eruption. Water (from condensed vapor) held at a shallow depth could then interact with quickly ascending magma, producing explosions. These processes do not appear to have occurred to the same extent at Colton Crater, as the eruption only experienced a brief period of phreatomagmatism. Models indicate that some vapor transport and condensation could have occurred outside the conduit during the eruption, producing a small amount of available water for MFCI, but explosions could have also been driven by a limited volume of perched water present in the shallow limestone unit prior to eruption. Results of this study aim to provide an example of a modeling approach for quantitative analysis of complex non-isothermal two-phase systems undergoing vaporization and condensation driven by magma intrusion, which can potentially be used for hazard assessment and monitoring for future eruptions in active volcanic regions