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Most experiments on ultrafast magnetodynamics have been conducted using the magneto-optical Kerr effect. Here, we compare the Kerr effect's magnetic sensitivity to the spin dynamics measured by photoemission. The magnetization dynamics on an Fe/W(110) thin film are probed by spin-resolved photoemission spectroscopy and the Kerr effect. The results reveal similarities between the spin dynamics at low binding energy and the response probed by the Kerr effect. Therefore, the Kerr effect probes states relevant for spin transport and spin flips but may not be sensitive to the entire magnetic moment in femtosecond spin dynamics experiments.

Objective To understand teachers’ perceptions about Breakfast in the Classroom and traditional breakfast. Design An electronic survey was sent to teachers across the state of Utah. Teachers responded to an open-ended question exploring what they liked and/or disliked about Breakfast in the Classroom and traditional breakfast. Setting Schools across the state of Utah. Participants Kindergarten through grade 12 teachers who were members of the Utah Education Association. Phenomenon of Interest Teachers’ opinions regarding Breakfast in the Classroom and traditional school breakfast Analysis Researchers independently coded all responses and then grouped codes into themes. Themes were reviewed recursively over time. Results The 3 overarching themes were food and nutrition, administration of school breakfast, and student outcomes. Aspects most commonly disliked were the nutrition or quality of food, the mess created, the time required, coordination and logistical issues, behavioral issues, and waste. Aspects most commonly liked were breakfast being available to all students, students being fed or not hungry, coordination and logistics, and student learning and academics. Conclusions and Implications Teachers liked and disliked aspects of Breakfast in the Classroom and traditional breakfast. Schools could potentially increase efforts to garner support and feedback from teachers to create buy-in and identify best practices. Future research could focus on identifying the effect that the School Breakfast Program model has on teachers’ perceptions as well as confirming results with a larger and more diverse population.

The majority of university family science courses are predominantly comprised of women. Because family science classes are centered on information and concepts relevant for both men and women, it is important to understand gendered experiences to promote healthy family and romantic relationships. Not only would men benefit from these classes, but increasing male enrollment in family sciences courses will help promote gender diversity in higher education. The current study used qualitative analyses to examine the perceptions of male undergraduate students concerning the benefits of taking family science courses. Male undergraduates from three midsize universities in the Midwestern and Western United States provided open-ended responses via an online survey (N = 64). Three themes emerged: the classes provided students with valuable information; they had a better understanding of themselves and others; and the classes related to their future career path. Results provide support to promote gender diversity in family science classrooms, which is crucial for the interpersonal and educational growth of both men and women. Further implications of participant responses are discussed.

We have split a student cohort into two parallel settings, a flipped learning group and a lecture group. Comparing the performance results of both groups we can draw conclusions on immediate and medium-term learning effects

Regulation fostering Managed Care alternatives in health insurance is spreading. This work reports on an experiment designed to measure the amounts of compensation asked by the Swiss population (in terms of reduced premiums) for Managed-Care type restrictions in the provision of health care. It finds that restrictions on the freedom of physician choice would require an average compensation of more than one-third of the premium, while generic substitution even meets with a small willingness to pay. Marked preference heterogeneity is an argument against regulation imposing uniformity of contract in Swiss social health insurance.

Adolescents are major consumers of interactive technologies (e.g., cell phones, social media). They are motivated to use these technologies to maintain their social relationships in a convenient and private way. The private nature and ease of connectivity afforded by interactive technology has resulted in various parental concerns (e.g., victimization, content) about adolescent technology use. To mitigate these parental concerns, some parents have begun to implement parental mediation strategies. Research has primarily focused on describing the different parental mediation techniques parents implement, parent and adolescent perceptions of parental mediation, and potential barriers to the implementation of parental mediation.

Prior to the development of pulsed lasers, one assigned a single local temperature to the lattice, the electron gas, and the spins. With the availability of ultrafast laser sources, one can now drive the temperature of these reservoirs out of equilibrium. Thus, the solid shows new internal degrees of freedom characterized by individual temperatures of the electron gas ${T}_{e}$, the lattice ${T}_{l}$ and the spins ${T}_{s}$. We demonstrate an analogous behavior in the spin polarization of a ferromagnet in an ultrafast demagnetization experiment: At the Fermi energy, the polarization is reduced faster than at deeper in the valence band. Therefore, on the femtosecond time scale, the magnetization as a macroscopic quantity does not provide the full picture of the spin dynamics: The spin polarization separates into different parts similar to how the single temperature paradigm changed with the development of ultrafast lasers.

Background Most local education agencies (LEA) report unpaid school meal debt. Starting July 2017, the USDA required LEAs to have an unpaid meal policy. The Food & Research Action Center released best practices for unpaid meal policies, including anti-shaming strategies. Objective The purpose of this study was to evaluate the strength of unpaid meal policies and examine the relationship between the policy strength and amount of debt. Study Design, Settings, Participants In this cross-sectional, primary data collection study, Food Service Directors (FSDs) from five states were recruited to complete an online survey. FSDs submitted unpaid meal policies and reported debt from 2017-18. Policies were reviewed and scored for strength of anti-shaming statements (0 = not present, 1 = weak, 2 = strong; 25 items scored). Measureable Outcome/Analysis The main outcome was the amount of school debt from full-price and reduced-price meals. Variables examined included percent of students enrolled in free and reduced-price lunch (FRL), LEA size and classification (urban, suburban, rural). Univariate statistics were summarized, bivariate relationships were examined through chi-square analysis. Results The sample was 59 FSDs. The FRL rate across the schools was 50.1% (± 18.6); 75% were rural schools. Few schools had strong policies; almost 40% of the sample had a score less than five. The highest frequency of school meal debt (23.1%) from full price meals was between $1,001-$5,000; four schools reported > $30,000 in debt from full price meals. For debt from reduced-price meals, 46% reported $1-$500 in unpaid meals; 20% reported no debt from reduced-price meals. There were no significant relationships between the amount of unpaid meal and strength of policy. Conclusion Many schools did not have strong anti-shaming policies. Because there was no relationship between strength of policy and amount of debt, LEAs can create stronger policies without concern for its effect on increased debt. Funding None.

Little is known about the role parental mediation plays in emerging adult technology use. As such, the current exploratory study was designed to identify the prevalence of parental mediation during this developmental period, ascertain how parents mediate, and understand the reasons parents elect not to mediate. Eighty-two unmarried college participants and 76 of their parents participated in this descriptive qualitative study. A majority of emerging adults and parents reported that parents did not mediate their child’s interactive technology. Reasons for not monitoring revolved around parental trust, child maturity, and parental priorities. For those who reported parental mediation, monitoring content and usage was the mediation technique most frequently implemented.

This exploratory study employed a qualitative approach and a strength-based framework to identify African Americans’ (N = 78) perceptions of help-seeking for marital problems in their strong marriages. Specifically, participants were asked the resources they would seek if marital problems arose, sex differences in willingness to seek professional help for marital problems, and their lived experience with help-seeking for marital problems. African American men and women most frequently cited religion/spirituality and family (immediate/extended) as resources for help during marital challenges. No significant difference was identified between men and women in willingness to seek professional help for marital problems. When discussing experiences with help-seeking for marital problems participants indicated that they considered the trustworthiness of the resource, typically relied on religion/spirituality, and preferred to keep their problems within their relationship. Results are discussed in terms of implications for researchers and marriage professionals.

The current exploratory study utilized a family strengths framework to identify marital expectations in 39 strong African American heterosexual marriages. Couples reflected on their marital expectations over their 10 or more years of marriage. Three themes emerged through qualitative analysis and the participants' own words were used in the presentation of the themes. African Americans indicated that there was growth in marital expectations over time, with marital expectations often beginning with unrealistic expectations that grew into more realistic expectations as their marriages progressed. Participants also indicated that core expectations in strong African American marriages included open communication, congruent values, and positive treatment of spouse. Finally, participants explained there is an “I” in marriage as they discussed the importance of autonomy within their marital relationships. Results are discussed in association with existing research and theory.

Although tremor is one of the most common movement disorders, it is evaluated using relatively coarse clinical scales. We propose to measure tremor in clinical settings using the Leap Motion Controller (LMC), which is a markerless motion capture sensor that has a low cost, zero set-up time, and dynamic accuracy of 1.2 mm. However, the frequency response of the LMC has not been characterized, so its ability to track oscillations such as tremor is unknown. To characterize the frequency response of the LMC, we measured the position of a mannequin hand simultaneously with the LMC and a high-resolution encoder while the mannequin hand oscillated at various combinations of frequency (1–15 Hz) and amplitudes (0.01–30 mm). We calculated the magnitude ratio and phase shift of the LMC and found the bandwidth of the LMC to range from 0–3 Hz to 0–5 Hz for tremor amplitudes greater than the dynamic accuracy. This bandwidth is too small to accurately measure most tremors. However, we developed an inverse filter to estimate the actual tremor amplitude and phase despite the limited bandwidth. Over the combinations of frequency and amplitude mentioned above, the inverse filter estimated the actual tremor amplitude and phase with errors of 3% and 2%, respectively.

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., Physical Review. Special Topics. Physics Education Research, 13 (1), ISSN:1554-9178

Structural Dynamics, 4 (1), ISSN:2329-7778

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).

Burgeoning technology provides instant access to information and communication. Responsible adults are concerned about the material accessed by adolescent technology users. From an ecological system's lens, using a mixed-methods design, the current study identified adolescent and parent perceptions of parental mediation of adolescent interactive technology use (i.e., cell phones, Internet). Eighty adolescents (16–18 years of age) and their parents (n = 113) participated in the study that identified generational differences in perceptions of parental mediation, techniques for mediating interactive technology (i.e., monitoring data and usage, active mediation, rules, restriction), and adolescent perceptions of the process of parental mediation. We used the results to propose principles for parental mediation of adolescent interactive technology use and provide directions for future research.

Loss and the associated grief process are part of the universal human experience (Murray, 2001). The losses that lead to grief can include, but are not limited to, death, trauma, abuse, war, reloca...

We report on the implementation of the SCALE-UP collaborative pedagogical approach in a first-year undergraduate physics class at ETH Zürich. The performance of the students on various assessments was compared with identical assessments in a parallel lecture class in order to gauge the effectiveness of this approach. Surveys were also given to get feedback on how students were reacting to this innovative style of pedagogy., Journal of Physics: Conference Series, 1286, ISSN:1742-6588, ISSN:1742-6596

Young adults (n = 702; 18–23 years old) completed measures of psychosocial development, identity status, and friendship. Friendship conflict and support were related with psychosocial development, and with the identity statuses. As per Erikson's prescription, early psychosocial stages were relevant to the identity statuses. After statistically controlling for the predictive variability contributed by trust, autonomy, initiative, and industry with the identity status measures, conflict and support within friendships contributed predictive variability to identity achievement (3.2%), moratorium (2.4%), and diffusion (2.5%), but neither conflict nor support within friendships was related to foreclosure scores. Conflict within friendships was positively related with moratorium and diffusion, and support within friendships was negatively related with diffusion.

We report on the design and tests of a completely mobile photoemission end station for femtosecond time, energy and spin resolved magnetodynamics experiments. The setup is designed for the use at free-electron laser (FEL) x-ray beamlines as well as at synchrotron facilities. In situ sample preparation in an adjacent UHV chamber is performed. The assembly can be altered to obtain energy resolved measurements with the help of a hemispherical electron energy analyzer or to obtain energy integrated measurements by inserting an electron transfer lens system. The magnetic information is obtained by spin analysis with a 50 kV Mott detector. The setup is tested in house with an electron gun, at the Swiss Light Source (SLS) and has been used at the FEL at FLASH in Hamburg. Results show the practicability of the system and exemplarily the kinetic energy dependent polarization of the low energy secondary electrons emitted from a 15 ML iron film on W(110) is presented.

As Stern–Gerlach type spin filters do not work with electrons, spin analysis of electron beams is accomplished by spin-dependent scattering processes based on spin–orbit or exchange interaction. Existing polarimeters are single-channel devices characterized by an inherently low figure of merit (FoM) of typically 10 −4 –10 −3 . This single-channel approach is not compatible with parallel imaging microscopes and also not with modern electron spectrometers that acquire a certain energy and angular interval simultaneously. We present a novel type of polarimeter that can transport a full image by making use of k -parallel conservation in low-energy electron diffraction. We studied specular reflection from Ir (001) because this spin-filter crystal provides a high analyzing power combined with a “lifetime” in UHV of a full day. One good working point is centered at 39 eV scattering energy with a broad maximum of 5 eV usable width. A second one at about 10 eV shows a narrower profile but much higher FoM. A relativistic layer-KKR SPLEED calculation shows good agreement with measurements.

Several relationship education (RE) programs have been implemented and funded through state and federal initiatives. Forming and sustaining university-community partnerships have been proposed as one way of maintaining these programs at the community level. Using a qualitative descriptive approach five Cooperative Extension faculty members articulated their experiences with university-community partnerships in providing RE programs in their counties for three years. Faculty members explained their purpose for developing partnerships, their leadership and roles within their partnerships, and how they maintain and evaluate their partnerships.

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., Structural Dynamics, 3 (5), ISSN:2329-7778

We developed a model of formative assessment and applied it to concept leaning in Physics at Swiss high schools. To studythe effect of formative assessment we recruited 30teachers and divided them into three groupswith at least 10 classes each. The groups formed are the experimental group with the formative assessment approach and two control groups. The first control group just applied tradition teaching without any instructional restrictions.The second control group was introduced to account for the effect of frequent testing. This group solved all the tests of the formative assessment group but not in the formative assessment approach.The goal of this work is to identify elements of our formative assessment approach which promote learning of physics concepts. The major differencesbetween solving concept questions as test questions or as clicker questions arepeer discussionsand classroom discussions. Therefore we compare in this study the formative assessment group to the frequent testing group. To estimate students’ concept knowledge before and after the teaching sequence we developed a kinematics concept test which we used as pre and post test. The topic taught during the teaching sequence was kinematics for which we have identified seven concepts. Our analysis revealed that after peer discussions the formative assessment group outperforms the two control groupsin the post test with respect to all seven concepts.