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We present experimental evidence of a spin voltage—a difference between the chemical potentials of the two spin directions—in a thin iron film based on spin- and time-resolved photoemission spectroscopy. This voltage is the driving force for a spin current during the ultrafast demagnetization of the sample. The observed magnitude is on the order of 50 mV, a value that is quite consistent with predictions based on particle conservation and persists for approximately 100 fs.

Ultrafast demagnetization of ferromagnetic metals can be achieved by a heat pulse propagating in the electron gas of a non-magnetic metal layer, which absorbs a pump laser pulse. Demagnetization by electronic heating is investigated on samples with different thicknesses of the absorber layer on nickel. This allows us to separate the contribution of thermalized hot electrons compared to non-thermal electrons. An analytical model describes the demagnetization amplitude as a function of the absorber thickness. The observed change of demagnetization time can be reproduced by diffusive heat transport through the absorber layer.

The laser-induced demagnetization of a ferromagnet is caused by the temperature of the electron gas as well as the lattice temperature. For long excitation pulses, the two reservoirs are in thermal equilibrium. In contrast to a picosecond laser pulse, a femtosecond pulse causes a non-equilibrium between the electron gas and the lattice. By pump pulse length dependent optical measurements, we find that the magnetodynamics in Ni caused by a picosecond laser pulse can be reconstructed from the response to a femtosecond pulse. The mechanism responsible for demagnetization on the picosecond time scale is therefore contained in the femtosecond demagnetization experiment.

The kinematics concept test (KCT) is a multiple-choice test designed to evaluate students’ conceptual understanding of kinematics at the high school level. The test comprises 49 multiple-choice items about velocity and acceleration, which are based on seven kinematic concepts and which make use of three different representations. In the first part of this article we describe the development and the validation process of the KCT. We applied the KCT to 338 Swiss high school students who attended traditional teaching in kinematics. We analyzed the response data to provide the psychometric properties of the test. In the second part we present the results of a structural analysis of the test. An exploratory factor analysis of 664 student answers finally uncovered the seven kinematics concepts as factors. However, the analysis revealed a hierarchical structure of concepts. At the higher level, mathematical concepts group together, and then split up into physics concepts at the lower level. Furthermore, students who seem to understand a concept in one representation have difficulties transferring the concept to similar problems in another representation. Both results have implications for teaching kinematics. First, teaching mathematical concepts beforehand might be beneficial for learning kinematics. Second, instructions have to be designed to teach students the change between different representations.

The Division for Early Childhood (DEC) clearly outlined recommended practices for the provision of Part C services. However, there may be challenges in rural areas associated with services aligning with these recommended practices. Therefore, this study focuses on how families experience Part C services and the extent to which services align with specific areas the DEC recommended practices in the large, rural state of Montana. We interviewed parents (N = 30) about their children's Part C services. Deductive qualitative content analysis was used. Parents' reports suggest that while some aspects of their Part C services align with specific recommended practices, others do not. There were some meaningful differences regarding alignment with these recommended practices depending on type of provider being described. The environments in which services take place are discussed, as these may influence aspects of collaboration and building family capacity.

Representational competence is essential for the acquisition of conceptual understanding in physics. It enables the interpretation of diagrams, graphs, and mathematical equations, and relating these to one another as well as to observations and experimental outcomes. In this study, we present the initial validation of a newly developed cross-contextual assessment of students' competence in representing vector-field plots and field lines, the most common visualization of the concept of vector fields. The "Representational Competence of Fields Inventory" (RCFI) consists of ten single choice items and two items that each contain three true or false questions. The tool can be easily implemented within an online assessment. It assesses the understanding of the conventions of interpreting field lines and vector-field plots, as well as the translation between these. The intended use of the tool is both to scale students' representational competences in respect to representations of vector fields and to reveal related misconceptions (areas of difficulty). The tool was administered at three German-speaking universities in Switzerland and Germany to a total of 515 first- and third-semester students from science, technology, engineering, and mathematics subjects. In these first steps of the validation of the RCFI, we evaluated its psychometric quality via classical test theory in combination with Rasch scaling and examined its construct validity by conducting student interviews. The RCFI exhibits a good internal consistency of [omega] = 0.86, and the results of the Rasch analysis revealed that the items discriminate well among students from lower to medium-high competence levels. The RCFI revealed several misunderstandings and shortcomings, such as the confusion of the conventions for representing field lines and vector-field plots. Moreover, it showed that many students believed that field lines must not exhibit a curvature, that the lengths of field lines matter, and that field lines may have sharp corners. In its current version, the RCFI allows assessing students' competence to interpret field representations, a necessary prerequisite for learning the widespread concept of vector fields. We report on planned future adaptations of the tool, such as optimizing some of the current distractors.

Relationship education (RE) has gained much public attention as classes have been implemented through state relationship initiatives. Developing university-community partnerships in implementing RE has been thought to increase access to underserved populations and increase awareness of healthy relationships in a community. Evaluation of these partnerships is just beginning. This three year longitudinal qualitative study represents five Cooperative Extension faculty members’ experiences with university-community partnerships in providing RE on a county level. Faculty members described their experiences identifying partners and outcomes from establishing partnerships and forming and sustaining partnerships. Results are discussed in terms of interdisciplinary university-community partnership literature and implications.

Objective: The current study extends research on the lack of male enrollment in undergraduate family science courses by examining the perspectives of male students who have never enrolled in these courses. Background: Although interpersonal and family relationships include all genders, the majority of undergraduate family science courses are primarily comprised of female students. Method: One hundred ten male undergraduate students from two universities answered open‐ended questions regarding why they had not enrolled in an undergraduate family science course. Results: Qualitative results revealed three themes: institutional constraints, gender stereotypes and gendered field of study, and lack of interest. Conclusion: The qualitative information provided by students is reflective of other studies examining gendered experiences in undergraduate settings but contradict some of the tenets of social role theory. Implications: These results infer practical suggestions to promote male enrollment in undergraduate family science courses. [ABSTRACT FROM AUTHOR]

Educators in a variety of disciplines have used clicker technology to engage college students in the learning process. This study investigated the influence of clicker technology on student recall and student involvement in higher education. Student Involvement Theory was used to inform and guide this research. Student recall was evaluated using three experimental conditions (1) verbal review (review without PowerPoint slide or clicker technology), (2) slide review (review with a PowerPoint slide and verbal review), and (3) clicker review (review with a PowerPoint slide, verbal review, and clicker technology). Also, student surveys were used to identify perceptions of involvement. Some evidence of improvement in student recall was identified with clicker technology review when compared to PowerPoint slides combined with verbal review. Student surveys indicated that students preferred clicker technology over the other conditions. Students also perceived benefits of clicker technology at a classroom level and on an individual engagement level. (Contains 1 table and 1 figure.)

Contemporary adolescents rely heavily on technology and media to navigate romantic relationships. In this mixed-methods study, adolescents and young adults (N = 204) detailed their perceptions of how entertainment media and interactive technology influence adolescent romantic relationships. The majority of adolescents and young adults perceived that entertainment media (95%) and interactive technology (97%) did influence adolescent romantic relationships. Using a qualitative analysis approach, we found six major themes. Although entertainment media provided media role models for expected behavior in romantic relationships, it was also associated with the development of unrealistic relational expectations and perceived pressure to be in a romantic relationship. Participants perceived that interactive technology has changed the way adolescents communicate with romantic partners, become integrated into the entire relationship life cycle, and led to a decline in face-to-face communication in adolescent romantic relationships.

This study aimed to (1) identify the perceived helpfulness of relationships and resources adolescents relied on in their transition to their parents' divorce or separation and (2) to ascertain any differences in experiences with these resources and relationships based on rurality. A retrospective design was implemented with 47 young adults who experienced parental divorce or separation between the ages of 10 and 18. Three themes were constructed through coding reliability thematic analysis. Participants indicated that helpful resources and relationships provided support in: (a) managing emotions following parental marital transitions, (b) reframing the experience of a parental marital transition, and (c) assistance with boundaries following a parental marital transition. Nearly half of the rural participants did not rely on formal resources (e.g., therapist/counselor), but across rurality levels the perceptions of what made these relationships and resources helpful in adapting to a parental marital transition were similar. [ABSTRACT FROM AUTHOR]

Text messaging, used by people of all ages, has become the preferred method of communication for teenagers. Teens spend a significant amount of their daytime hours in school. Schools have not readily accepted the use of cell phone technology for fear of academic dishonesty, distraction, and cyberbullying. The current study examined adolescent (n = 218) attitudes concerning text messaging in school. The majority of adolescents (71%) supported text messaging in school. A phenomenological qualitative approach revealed that adolescents' experience with texting and school centers on student attention, connection (with family, friends, and emergency responders), and levels of regulation (personal, circumstantial, and school).

Purpose/Objectives: The purpose of this exploratory, observational study was three-fold: 1) Determine current food safety practices at Summer Food Service Program (SFSP) sites; 2) Identify types of food served at the sites and collect associated temperatures; and 3) Establish recommendations for food safety training in the SFSP. Methods:Twenty-eight SFSP sites in seven states were observed during preparation, service, and clean-up to assess food safety practices. Before the study, researchers participated in a day and half training session which included a pilot test of the observation tools at school kitchens. Individuals completed the forms and in pairs they compared findings; final adjustments to the observation forms were made. Descriptive statistics were calculated using Excel. Results: Twenty-five sites had at least one employee or volunteer who reported having had food safety training. Proper handwashing facilities were available and accessible at most preparation sites (n = 21) and fewer service sites (n = 15). Proper handwashing (n = 14), glove changing (n = 13), and thermometer use (n = 10) were commonly out of compliance among observed sites. Application to Child Nutrition Professionals: As the SFSP expands, assuring food safety is important to the success of the program. Overall improvement is needed in personal hygiene, time/temperature control, and cleaning/sanitizing practices. New program sponsors may benefit from careful planning with food safety in mind and should provide relevant food safety training to employees and volunteers. State agencies may assist sponsors in meeting food safety training needs.

The kinematics concept test (KCT) is a multiple-choice test designed to evaluate students' conceptual understanding of kinematics at the high school level. The test comprises 49 multiple-choice items about velocity and acceleration, which are based on seven kinematic concepts and which make use of three different representations. In the first part of this article we describe the development and the validation process of the KCT. We applied the KCT to 338 Swiss high school students who attended traditional teaching in kinematics. We analyzed the response data to provide the psychometric properties of the test. In the second part we present the results of a structural analysis of the test. An exploratory factor analysis of 664 student answers finally uncovered the seven kinematics concepts as factors. However, the analysis revealed a hierarchical structure of concepts. At the higher level, mathematical concepts group together, and then split up into physics concepts at the lower level. Furthermore, students who seem to understand a concept in one representation have difficulties transferring the concept to similar problems in another representation. Both results have implications for teaching kinematics. First, teaching mathematical concepts beforehand might be beneficial for learning kinematics. Second, instructions have to be designed to teach students the change between different representations.