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Involvement with the 4-H program during youth has been empirically shown to have positive effects on participants and to influence their life perspectives and career development. The activities offered within 4-H allow individuals to build relationships with peers and mentors, develop life and leadership skills, and create a positive self-concept. The focus of this study was to identify key touchstones which influenced 4-H alumni life perspectives and inform program development to ensure individuals are exposed to these activities during their 4-H involvement. Although numerous studies have examined the positive outcomes of 4-H programming, limited research exists identifying the context in which these influential experiences occur. This study employed a modified Delphi approach, using an expert panel (n = 31) to identify and generate consensus regarding 4-H experiences, events, and programs deemed influential in expanding alumni life perspectives. Thirty-six items were retained following the Delphi process. Two items received unanimous consensus: (1) interaction with diverse groups; and (2) hearing dynamic speakers and listening to accomplishments they have achieved because of involvement in 4-H. Retained items were analyzed for overarching themes using the constant comparative method (CCM). Five themes emerged following the CCM analysis: (1) professional skills and leadership development; (2) networking and mentorship opportunities; (3) 4-H events, programs, and camps; (4) 4- H projects and educational opportunities; and (5) internal influences. These themes may be combined with Robert's (2006) model of experiential learning to identify the appropriate setting, duration, level, and intended outcomes of 4-H programming.

Purpose: The purpose was to analyze perceptions of knowledge management capacity in extension networks using an exploratory factor analysis approach. Design/methodology/approach: The knowledge management content domain was analyzed for content validity, response process validity, internal structure validity, and consequential validity. A pilot version of an instrument was administered to extension network members (n = 122) associated with the Global Forum for Rural Advisory Services. Exploratory factor analysis (EFA) and measures of correlation and reliability were performed to determine the structure and internal consistency of the scale. Findings: The observed structure was similar to the hypothesized structure. EFA indicates further factor analyses should be performed on the aggregate scale and proposed subscales. Practical Implications: The resulting scale has the potential to serve as the basis for a reliable instrument for establishing perceptions of knowledge management capacity, supplementing needs assessment strategies, and informing organizational practices and policy which maximize these capacities in extension services. Theoretical Implications: The resulting scale advances the activity theory framework by conceptualizing dimensions of knowledge management that facilitate development via social interaction. Originality/Value: While various studies have been conducted to analyze the knowledge management capacities of international extension networks, the current study introduces preliminary results of an instrument to discretely quantify perceptions of knowledge management capacity in extension services.

Purpose: This study aims to examine factors that impact participation of diverse university students in an academic sustainability certificate and Office of Sustainability internships at the University of Georgia, recognizing the need for diverse voices and perspectives in addressing sustainability challenges and the current lack of diverse representation in the field. Design/methodology/approach: A convenience sample of 77 student organizations and 35 departments, schools and colleges associated with the university was identified. The questionnaire was created using the Qualtrics online survey platform and distributed via email to potential participants. A total of 234 completed responses were collected. Descriptive statistics were calculated to determine the demographic composition of the sample. One-way ANOVAs were performed to examine the relationship between respondent demographics and perceptions of sustainability and participation in campus sustainability programs. Post hoc tests were conducted using Fisher's least significant difference procedure. Findings: Significant relationships were observed between perceptions of sustainability and race and current gender. A significant relationship was observed between race and participation in campus sustainability programs. Overall, students from diverse backgrounds believe that sustainability efforts contribute to racial justice and equity. Additionally, students from diverse backgrounds do want to participate in campus sustainability programs; however, there may be barriers preventing their participation. Originality/value: This study examines how students from diverse backgrounds perceive sustainability efforts, as well as their interest in participating in campus sustainability programs. The results of this study can be used to inform recruitment and program development strategies for sustainability programs at higher education institutions. At the time of publication, no study could be located that examines the current study outcomes.

Rural stress is the physiological reaction brought upon by internal and socioeconomic stressors characteristic of rural residents. This type of stress is exacerbated by the complex issues facing rural populations and serves to inhibit the growth of vibrant, resilient communities. The current study sought to construct and validate an instrument intended to quantify perceptions of rural stress among neighbors and communities. The proposed scale was confirmed to have robust content, internal structure, and consequential validity. An exploratory factor analysis indicated one variable accounted for 57.74% of the total variance, while a one-way between subjects ANOVA found a statistically significant effect of group on scale scores under rural-urban continuum (RUC) conditions. One implication from these findings is that changes in communities may function as predictors of stress. Agricultural and extension educators hold a unique position that allows them to interact with the community on a daily basis. We recommend that they leverage this position to educate residents on the effects of stress, reduce the stigma associated with help-seeking behaviors, and discuss available stress management resources. Future research should consider modifying the instrument to focus on individual levels of stress instead of perceptions of stress within the community.

Research and societal trends indicate the necessity and permanency of teamwork skills in the workplace thus investigating the relationship between satisfaction and students' experiences of team and group work is essential. Taking a novel and comprehensive approach the current research study examined the effect of multiple antecedent conditions on undergraduate project team satisfaction. Specifically, a structural model was proposed and tested to examine the effects of clarity, justice, frustration, and fit on project team satisfaction. The model was able to predict 52.7% of the variance associated with project team satisfaction. Among the predictor variables clarity had the largest total (direct and indirect) effect on satisfaction. Frustration was found to have the next largest total effect. Consequently, agricultural educators are encouraged to first focus on clearly articulating the expectations associated with project teams as well as to monitor project teams for emerging frustration and to intervene as appropriate.

The importance of knowing and employing strategies to effectively motivate learners is well established. This is also true for leadership educators that have a mandate to build leadership capacity amongst learners in various environments. However, despite the importance of learner motivation in learning environments, there has been a lack of empirical studies to determine if there may be dispositional trends related to motivational tendencies based on demographic categories, specifically within adult agricultural leadership development program participants. The current study analyzed goal orientation disposition across demographic categories including gender, age, organizational level, educational attainment, and geographic region amongst alumni of adult agricultural leadership development programs. The results indicate there are trends related to demographic categories leadership educators may consider using as entry points to more effectively motivate learners based on dispositional tendencies. For example, the results imply desire to prove competence relative to peers decreases with age. Therefore, a recommendation for educators would be to target strategies fostering healthy competition towards younger learners and target strategies providing opportunities for learning and personal reflection towards older learners. Additionally, a significant non-finding is goal orientation, not influenced by cognitive ability, is independent of educational attainment. A recommendation then is for educators to not base motivational strategies on cognitive ability or educational attainment. Further research is needed to extend the results of the present study to a much larger population of adults engaged in agriculture across the globe.

Ensuring that the experiences provided by Extension, including those associated with the 4-H program, are impactful to participants is of paramount importance. To ensure the continued success and relevance of the 4-H program, it is crucial for practitioners to measure the impact of 4-H involvement and use these results to develop highly impactful programs. This study proposed and validated the Impacts of 4-H scale. The scale was developed based on previous research and literature review. Based on content, response process, and internal structure validation, a single factor consisting of eight items was proposed. The results of the study indicate the proposed scale may provide a valid and reliable measure to capture, quantify, and report the impacts associated with participating in the 4-H program. Additional recommendations for future research and practice are provided.

Previous work has shown that activation of tiger salamander retinal radial glial cells by extracellular ATP induces a pronounced extracellular acidification, which has been proposed to be a potent modulator of neurotransmitter release. This study demonstrates that low micromolar concentrations of extracellular ATP similarly induce significant H+ effluxes from Müller cells isolated from the axolotl retina. Müller cells were enzymatically isolated from axolotl retina and H+ fluxes were measured from individual cells using self-referencing H+-selective microelectrodes. The increased H+ efflux from axolotl Müller cells induced by extracellular ATP required activation of metabotropic purinergic receptors and was dependent upon calcium released from internal stores. We further found that the ATP-evoked increase in H+ efflux from Müller cells of both tiger salamander and axolotl were sensitive to pharmacological agents known to interrupt calmodulin and protein kinase C (PKC) activity: chlorpromazine (CLP), tri-fluoperazine (TFP), and W-7 (all calmodulin inhibitors) and chelerythrine, a PKC inhibitor, all attenuated ATP-elicited increases in H+ efflux. ATP-initiated H+ fluxes of axolotl Müller cells were also significantly reduced by amiloride, suggesting a significant contribution by sodium-hydrogen exchangers (NHEs). In addition, α-cyano-4-hydroxycinnamate (4-cin), a monocarboxylate transport (MCT) inhibitor, also reduced the ATP-induced increase in H+ efflux in both axolotl and tiger salamander Müller cells, and when combined with amiloride, abolished ATP-evoked increase in H+ efflux. These data suggest that axolotl Müller cells are likely to be an excellent model system to understand the cell-signaling pathways regulating H+ release from glia and the role this may play in modulating neuronal signaling. [ABSTRACT FROM AUTHOR]

Small alterations in extracellular H+ can profoundly alter neurotransmitter release by neurons. We examined mechanisms by which extracellular ATP induces an extracellular H+ flux from Müller glial cells, which surround synaptic connections throughout the vertebrate retina. Müller glia were isolated from tiger salamander retinae and H+ fluxes examined using self-referencing H+-selective microelectrodes. Experiments were performed in 1 mM HEPES with no bicarbonate present. Replacement of extracellular sodium by choline decreased H+ efflux induced by 10 µM ATP by 75%. ATP-induced H+ efflux was also reduced by Na+/H+ exchange inhibitors. Amiloride reduced H+ efflux initiated by 10 µM ATP by 60%, while 10 µM cariporide decreased H+ flux by 37%, and 25 µM zoniporide reduced H+ flux by 32%. ATP-induced H+ fluxes were not significantly altered by the K+/H+ pump blockers SCH28080 or TAK438, and replacement of all extracellular chloride with gluconate was without effect on H+ fluxes. Recordings of ATP-induced H+ efflux from cells that were simultaneously whole cell voltage clamped revealed no effect of membrane potential from -70 mV to 0 mV. Restoration of extracellular potassium after cells were bathed in 0 mM potassium produced a transient alteration in ATP-dependent H+ efflux. The transient response to extracellular potassium occurred only when extracellular sodium was present and was abolished by 1 mM ouabain, suggesting that alterations in sodium gradients were mediated by Na+/K+-ATPase activity. Our data indicate that the majority of H+ efflux elicited by extracellular ATP from isolated Müller cells is mediated by Na+/H+ exchange. NEW & NOTEWORTHY Glial cells are known to regulate neuronal activity, but the exact mechanism(s) whereby these "support" cells modulate synaptic transmission remains unclear. Small changes in extracellular levels of acidity are known to be particularly powerful regulators of neurotransmitter release. Here, we show that extracellular ATP, known to be a potent activator of glial cells, induces H+ efflux from retinal Müller (glial) cells and that the bulk of the H+ efflux is mediated by Na+/H+ exchange. [ABSTRACT FROM AUTHOR]

Previous work has shown that activation of tiger salamander retinal radial glial cells by extracellular ATP induces a pronounced extracellular acidification, which has been proposed to be a potent modulator of neurotransmitter release. This study demonstrates that low micromolar concentrations of extracellular ATP similarly induce significant H + effluxes from Müller cells isolated from the axolotl retina. Müller cells were enzymatically isolated from axolotl retina and H + fluxes were measured from individual cells using self-referencing H + -selective microelectrodes. The increased H + efflux from axolotl Müller cells induced by extracellular ATP required activation of metabotropic purinergic receptors and was dependent upon calcium released from internal stores. We further found that the ATP-evoked increase in H + efflux from Müller cells of both tiger salamander and axolotl were sensitive to pharmacological agents known to interrupt calmodulin and protein kinase C (PKC) activity: chlorpromazine (CLP), trifluoperazine (TFP), and W-7 (all calmodulin inhibitors) and chelerythrine, a PKC inhibitor, all attenuated ATP-elicited increases in H + efflux. ATP-initiated H + fluxes of axolotl Müller cells were also significantly reduced by amiloride, suggesting a significant contribution by sodium-hydrogen exchangers (NHEs). In addition, α-cyano-4-hydroxycinnamate (4-cin), a monocarboxylate transport (MCT) inhibitor, also reduced the ATP-induced increase in H + efflux in both axolotl and tiger salamander Müller cells, and when combined with amiloride, abolished ATP-evoked increase in H + efflux. These data suggest that axolotl Müller cells are likely to be an excellent model system to understand the cell-signaling pathways regulating H + release from glia and the role this may play in modulating neuronal signaling. NEW & NOTEWORTHY Glial cells are a key structural part of the tripartite synapse and have been suggested to regulate synaptic transmission, but the regulatory mechanisms remain unclear. We show that extracellular ATP, a potent glial cell activator, induces H + efflux from axolotl retinal Müller (glial) cells through a calcium-dependent pathway that is likely to involve calmodulin, PKC, Na + /H + exchange, and monocarboxylate transport, and suggest that such H + release may play a key role in modulating neuronal transmission.

Small alterations in extracellular H + can profoundly alter neurotransmitter release by neurons. We examined mechanisms by which extracellular ATP induces an extracellular H + flux from Müller glial cells, which surround synaptic connections throughout the vertebrate retina. Müller glia were isolated from tiger salamander retinae and H + fluxes examined using self-referencing H + -selective microelectrodes. Experiments were performed in 1 mM HEPES with no bicarbonate present. Replacement of extracellular sodium by choline decreased H + efflux induced by 10 µM ATP by 75%. ATP-induced H + efflux was also reduced by Na + /H + exchange inhibitors. Amiloride reduced H + efflux initiated by 10 µM ATP by 60%, while 10 µM cariporide decreased H + flux by 37%, and 25 µM zoniporide reduced H + flux by 32%. ATP-induced H + fluxes were not significantly altered by the K + /H + pump blockers SCH28080 or TAK438, and replacement of all extracellular chloride with gluconate was without effect on H + fluxes. Recordings of ATP-induced H + efflux from cells that were simultaneously whole cell voltage clamped revealed no effect of membrane potential from -70 mV to 0 mV. Restoration of extracellular potassium after cells were bathed in 0 mM potassium produced a transient alteration in ATP-dependent H + efflux. The transient response to extracellular potassium occurred only when extracellular sodium was present and was abolished by 1 mM ouabain, suggesting that alterations in sodium gradients were mediated by Na + /K + -ATPase activity. Our data indicate that the majority of H + efflux elicited by extracellular ATP from isolated Müller cells is mediated by Na + /H + exchange. NEW & NOTEWORTHY Glial cells are known to regulate neuronal activity, but the exact mechanism(s) whereby these "support" cells modulate synaptic transmission remains unclear. Small changes in extracellular levels of acidity are known to be particularly powerful regulators of neurotransmitter release. Here, we show that extracellular ATP, known to be a potent activator of glial cells, induces H + efflux from retinal Müller (glial) cells and that the bulk of the H + efflux is mediated by Na + /H + exchange.