Potassium self-diffusion in a K-rich single-crystal alkali feldspar

The paper reports potassium diffusion measurements performed on gem-quality single-crystal alkali feldspar in the temperature range from $1169$ to 1021 \, \mbox{K}. Natural sanidine from Volkesfeld, Germany was implanted with \mbox{}^{43}\mbox{K} at the ISOLDE/CERN radioactive ion-beam facility normal to the (001) crystallographic plane. Diffusion coefficients are well described by the Arrhenius equation with an activation energy of 2.4 \, \mbox{eV} and a pre-exponential factor of 5\times10^{-6} \, \mbox{m}^{2}/\mbox{s}, which is more than three orders of magnitude lower than the \mbox{}^{22}\mbox{Na} diffusivity in the same feldspar and the same crystallographic direction. State-of-the-art considerations including ionic conductivity data on the same crystal and Monte Carlo simulations of diffusion in random binary alloy structures point to a correlated motion of K and Na through the interstitialcy mechanism

Dampak Perceraian Terhadap Kepribadian Anak (Studi Pada Keluarga Yang Bercerai Di Desa Melong Kecamatan Melonguane Kabupaten Kepulauan Talaud)

Penelitian ini bertujuan untuk mengetahui lebih dalam bagaimana dampak perceraian terhadap kepribadian anak studi pada keluarga yang bercerai di Desa Melong Kecamatan Melonguane Kabupaten Kepulauan Talaud. Penelitian ini menggunakan metode kualitatif dan dengan teknik pengumpulan data melalui observasi, wawancara dan dokumentasi. Teori yang digunakan sebagai alat analisis penelitian ini adalah Moleong, lexy. Perceraian dapat diartikan sebagai berkahirnya suatu hubungan suami dan istri yang diputuskan oleh hukum atau agama karena sudah tidak ada saling ketertarikan. saling percaya dan juga sudah tidak ada kecocokan satu sama lain sehingga menyebabkan ketidak harmonisan dalam rumah tangga. Didalam Undang-undang No 1 tahun 1974 pasal 9 dinyatakan perceraian hanya dapat dilakukan di depan sidang pengadilan setelah yang bersangkutan berusaha dan tidak berhasil mendamaikan kedua belah pihak. Untuk melakukan perceraian harus ada cukup alasan bahwa antara suami dan istri itu tidak akan hidup rukun sebagai suami istri. Dari hasil penelitian ini ditemukan bahwa perceraian Apabila dalam suatu keluarga tidak dapat melaksanakan fungsinya, maka keluarga tersebut berarti mengalami stagnasi atau disfungsi yang pada gilirannya akan merusak kokohan konstelasi keluarga tersebut (khususnya terhadap perkembangan kepribadian anak). Organisasasi wanitia Se-Asia Pasifik dalam konfrensinya yang ke-20 di Kuala Lumpur Malaysia menyimpulkan bahwa kerusakan yang terjadi pada keluarga di abad ke-20 semakin memburuk. Percerian diperkirakan sekitar 40%-50% generasi mendatang akan menjadi keluarga yang broken home, akibat perceraian orang tuanya.   Kata kunci: Dampak, Perceraian, Anak &nbsp

Development and evaluation of the Measure of the International Learning Environment Status (MILES) in international higher education

The aim of this study was to develop and evaluate an instrument to assess international students' perceptions of the international learning environment called 'Measure of the International Learning Environment Status' (MILES). We based the development of the MILES on a solid theoretical framework from Moos by addressing three domains to measure the quality of the international learning environment, namely goal direction, relationships, and system change and system maintenance. We have designed and constructed the instrument in three steps. Firstly, we have collected items from relevant existing instruments and grouped them into the three domains via content analysis. Secondly, we applied a Delphi procedure involving international higher education experts from different stakeholder groups and from different cultural backgrounds to identify and reach consensus on the items comprehensively covering important elements of the international learning environment. Thirdly, we carried out an initial questionnaire evaluation. The final MILES consisted of 47 items with 13 in the first domain, 17 in the second and 17 in the third domain. The content of the domains was clearly in line with Moos theoretical framework and we interpreted the sets of items as goal direction, relationships, and supporting services, respectively. This study provides a comprehensive and systematically developed instrument for future research to better understand international students' perspectives towards the international learning environment that are supported by stakeholders from a range of cultures.</p

Student engagement and learning outcomes:an empirical study applying a four-dimensional framework

Introduction: This study applies Reeve’s four-dimensional student engagement framework to a medical education context to elucidate the relationship between behavioral, emotional, cognitive, and agentic engagement and learning outcomes. Meanwhile, we categorize learning outcomes in knowledge and skills, and added taxonomies to the cognitive education objectives for the knowledge part, including memorization, comprehension, and application. Methods: We used the China Medical Student Survey to investigate student engagement, and combined it with the Clinical Medicine Proficiency Test for Medical Schools results as a standardized measurement of learning outcomes. We performed multivariate regression analyses to delve into the effectiveness of different types of student engagement. Moreover, we evaluated the moderating roles of gender and the National College Entrance Examination (NCEE) within the relationships between student engagement and learning outcomes. Results: We observed that emotional engagement is most effective in promoting learning outcomes in basic medical knowledge and basic clinical skills. Emotional engagement and cognitive engagement could effectively contribute to learning outcomes in all three aspects of basic medical knowledge. In contrast, behavioral and agentic engagement showed negative effects on learning outcomes. Besides, we found that the results of the NCEE played a positive moderating role. Conclusion: This study provides robust evidence for the effectiveness of emotional engagement and cognitive engagement in promoting learning outcomes. Whereas behavioral and agentic engagement may not be good predictors of learning outcomes in macro-level general competence tests. We suggest a combined effort by students and institutions to promote student engagement and bridge the distance between general competency tests and daily learning activities.</p

Fatty Acid-Derived Biofuels and Chemicals Production in Saccharomyces cerevisiae

Volatile energy costs and environmental concerns have spurred interest in the development of alternative, renewable, sustainable and cost-effective energy resources. Advanced biofuels have potential to replace fossil fuels in supporting high-power demanding machinery such as aircrafts and trucks. Microbial biosynthesis is generally considered as an environmental friendly refinery process, and fatty acid biosynthesis is an attractive route to synthesize chemicals and especially drop-in biofuels due to the high degree of reduction of fatty acids. The robustness and excellent accessibility to molecular genetics make the yeast S. cerevisiae a suitable host for the production of biofuels, chemicals and pharmaceuticals, and recent advances in metabolic engineering as well as systems and synthetic biology allow us to engineer the yeast fatty acid metabolism and modification pathways for production of advanced biofuels and chemicals