Epsilon-Near-Zero Al-Doped ZnO for Ultrafast Switching at Telecom Wavelengths: Outpacing the Traditional Amplitude-Bandwidth Trade-Off

Transparent conducting oxides have recently gained great attention as CMOS-compatible materials for applications in nanophotonics due to their low optical loss, metal-like behavior, versatile/tailorable optical properties, and established fabrication procedures. In particular, aluminum doped zinc oxide (AZO) is very attractive because its dielectric permittivity can be engineered over a broad range in the near infrared and infrared. However, despite all these beneficial features, the slow (> 100 ps) electron-hole recombination time typical of these compounds still represents a fundamental limitation impeding ultrafast optical modulation. Here we report the first epsilon-near-zero AZO thin films which simultaneously exhibit ultra-fast carrier dynamics (excitation and recombination time below 1 ps) and an outstanding reflectance modulation up to 40% for very low pump fluence levels (< 4 mJ/cm2) at the telecom wavelength of 1.3 {\mu}m. The unique properties of the demonstrated AZO thin films are the result of a low temperature fabrication procedure promoting oxygen vacancies and an ultra-high carrier concentration. As a proof-of-concept, an all-optical AZO-based plasmonic modulator achieving 3 dB modulation in 7.5 {\mu}m and operating at THz frequencies is numerically demonstrated. Our results overcome the traditional "modulation depth vs. speed" trade-off by at least an order of magnitude, placing AZO among the most promising compounds for tunable/switchable nanophotonics.Comment: 14 pages, 9 figures, 1 tabl

The cooperative learning: Understanding and increasing the knowledge of the facilities design without a professor extra effort

[EN] Lecturing has been prevailing in higher education. This teaching and learning model hinders the understanding of fundamental concepts in practical courses. The cooperative learning allows an improvement in the student’s achievements, attitudes and persistence. The main goal of this work is to implement the cooperative learning in the teaching of the design of industrial facilities. This methodology aims to solve part of the problems of recently graduate students when they undertake engineering projects lacking knowledge. Finally, the results of an end-of-course satisfaction survey, conducted to assess this experience, are also presented.The authors gratefully acknowledge the financial support provided by the Servicio de Orientación y Formación Docente (Guidance and Teacher Education Service) from University of Extremadura under the context of actions for the Consolidation of the European Higher Education at the University of Extremadura.Ferrera, C.; Fernández, J.; Marcos, A. (2014). The cooperative learning: Understanding and increasing the knowledge of the facilities design without a professor extra effort. Multidisciplinary Journal for Education, Social and Technological Sciences. 1(2):1-18. doi:http://dx.doi.org/10.4995/muse.2014.3262.SWORD11812Aubert, A., Flecha, A., García, C., Flecha, R. and Racionero, S. (2008). Aprendizaje dialógico en la sociedad de la Información. Barcelona. Ed. Hipatia.Aubert, A., Medina, A. and Sánchez, M., (2000). De las agrupaciones flexibles a los grupos interactivos. VIII Conferencia de sociología de la educación, Madrid, Espa-a.Castells M., Flecha, R., Freire, P., Giroux, H., Macedo, D. and Willis, P. (1994). Nuevas perspectivas críticas en educación. Ed Paredes.Chickering, A. W. and Gamson, Z. F. (1987). Seven principles for good practice in undergraduate education. Wingspread Journal.Dale, E. (1946). Audio-visual methods in teaching. New York: The Dryden Press.Downing, C. E. and Liu, C. (2012). Getting Students to Teach Each Other: Doing More with Less in IS Education Journal of Information Technology and Application in Education Vol. 1 Iss. 4, 195-206.Flecha, R., Lloret, C. and García, J. M. (1977). Transformemos la escuela. Ed. Renacimiento.Flecha, R. (1997). Compartiendo palabras. El aprendizaje de las personas a través del diálogo. Ed. Paidós Ibérica.Lewis, K. G. (1994) Teaching Large Classes (How to Do It Well and Remain Sane), Chapter 25 in Handbook of College Teaching, edited by K.W. Prichard and R.McL. Sawyer. Westport, Conn.: Greenwood Press.Luzuriaga, L. (1977). Historia de la educación y la pedagogía. Ed. Losada.Mazur, E. (1992). Qualitative vs. Quantitative Thinking: Are We Teaching the Right Thin?", Optics and Photonics News.Mazur, E., & Hilborn, R. C. (1997). Peer Instruction: A User’s Manual. Physics Today, 50(4), 68-69. doi:10.1063/1.881735Michaelsen, L. K., (1983). Team Learning in Large Classes. Chapter 2 in Learning in Groups, New Directions for Teaching and Learning series, 14. San Francisco: Jossey-Bass.Michaelsen, L. K., Knight, A. B. and Fink, L. D. (2003). Preface. In L. K. Michaelsen, A. B. Knight, & L. D. Fink (Eds.), Team-based learning: A transformative use of small groups, (pp. vii-xi). Westport, CT: Praeger.Nyquist, J. D., Abbott, R. D., Wulff, D. H. and Sprague, J. (1991). Preparing the Professorate of Tomorrow to Teach: Selected Readings in TA Training. Kendall/Hunt.Paris, S. G. and Turner, J. C. (1994). Situated motivation. In P. R. Pintrich, D. R. Brown, & C. E. Weinstein (Eds.), Student motivation, cognition, and learning: Essays in honor of Wilbert J. McKeachie (pp. 213-238). Hillsdale, NJ: Erlbaum.Saye. D. (1997). An alternative technique for teaching mathematics: students teach. Proceddings of the 23rd AMATYC Annual Conference Atlanta, USA.Sheetz, L. P. (1995). Recruiting trends: 1995-1996. East Lansing, MI: Collegiate Employment Research Institute, Michigan State University.Smith, F. (1998). The book of learning and forgetting. New York: Teachers College Press.Stanly, C. and Porter, M. E. (2002). Engaging Large Classes: Strategies and Techniques for College Faculty . Onker Publishing.Sugata, M., Dangwal, R., Chatterjee, S., Jha, S., Bisht R. S. and Kapur, P. (2005). Acquisition of Computer Literacy on Shared Public Computers: Children and the "Hole in the wall". Australasian Journal of Educational Technology, 21(3), 407-426.Redish, E. F. (2003). Teaching physics with the physics suite. John Wiley & Sons.Weimer, M. (2002). Learner-centered teaching: Five key changes to practice. San Francisco: Jossey-Bass.Winchester-Seeto, T. (2002). Assesment of collaborative work-collaboration versus assesment. Invited paper. Annual Uniserve Science Symposium. University of Sydney. Australia

An overview of top-down vs. bottom-up models for informal settlement upgrading in South Africa

The paper explores informal settlement upgrading approaches in South Africa and presents a review of top-down vs. bottom-up models, using experience and lessons learned from the Durban metropolitan area. Reflections on past upgrading efforts suggest that top-down policies in South Africa have not been successful to date. By contrast, participatory techniques, such as planning activism, can be used to enhance community empowerment and a sense of local ownership. This paper reveals that although the notion of ‘bottom-up’, participatory methods for community improvement is often discussed in international development discourses, the tools, processes and new knowledge needed to ensure a successful upgrade are under-utilised. Participation and collaboration can mean various things for informal housing upgrading and often the involvement of local communities is limited to providing feedback in already agreed development decisions from local authorities and construction companies. The paper concludes by suggesting directions for ‘co-producing’ knowledge with communities through participatory, action-research methods and integrating these insights into upgrading mechanisms and policies for housing and infrastructure provision. The cumulative impacts emerging from these approaches could aggregate into local, regional, and national environmental, social and economic benefits able to successfully transform urban areas and ensure self-reliance for local populations

Financially Wiser: using financial management to improve the wellbeing of young and middle-aged adults in the community

There is evidence that a person’s financial situation is associated with their wellbeing now and in the future. However, financial stress is present in many adults’ lives, impacting their role and participation in different occupational domains such as work, health management, and instrumental activities of daily living. Financial stress is consistently one of the top three causes of stress in the United States (APA, 2015). Financial stress is associated with cumulative effects that have a negative impact on a person’s physical health (Gallo et al., 2011; Kahn & Pearlin, 2006; Sturgeon et al., 2016) and mental health (Fitch et al., 2011; Mucci et al., 2016). Improving a person’s financial wellbeing is one way to mitigate financial stress. This project focused on the factors affecting a person’s financial decision-making skills and behavior, leading to financial stress or financial wellbeing. The evidence literature and current approaches were reviewed and contributed to the development of Financially Wiser, a theory-driven evidence-based approach for developing financial literacy and positive financial management behavior that leads to improved financial wellbeing. Financially Wiser is designed as a community-based financial management education program facilitated by an occupational therapist. A pre-test post-test evaluation will be conducted to determine participant satisfaction and the degree to which the program goals were achieved

Episodic breathlessness with and without background dyspnea in advanced cancer patients admitted to an acute supportive care unit

Aim: To characterize episodic breathlessness (EB) in patients with advanced cancer, and to determine factors influencing its clinical appearance. Methods: A consecutive sample of advanced cancer patients admitted to an acute palliative care unit was surveyed. Continuous dyspnea and EB were measured by a numerical scale. The use of drugs used for continuous dyspnea and EB was recorded. Patients were asked about the characteristics of EB (frequency, intensity, duration and triggers). The Multidimensional dyspnea profile (MDP), the Brief dyspnea inventory (BDI), the Athens sleep scale (AIS) and the Hospital Anxiety and Depression Scale (HADS) were also administered. Results: From 439 advanced cancer patients surveyed, 34 and 27 patients had EB, without and with background dyspnea, respectively. The mean intensity and the number of episodes were higher in patients with background dyspnea (p &lt; 0.0005 and p = 0.05, respectively). No differences in duration were observed. Most episodes lasted &lt;10 min. A recognizable cause triggering EB was often found. The presence of both background dyspnea and EB was associated with higher values of MDP and BDI. EB was independently associated with frequency and intensity of background dyspnea (OR = 20.9, 95% CI (Confidence interval) 9.1–48.0; p &lt; 0.0005 and OR = 1.97, 95% CI 1.09–3.58; p = 0.025, respectively) and a lower Karnofsky level (OR = 0.96, 95%CI 0.92–0.98, p = 0.05). Discussion: EB may occur in patients with and without continuous dyspnea, and is often induced by physical and psychological factors. EB intensity is higher in patients with continuous dyspnea. The duration was often so short that the use of drugs, as needed, may be too late, unless administered pre-emptively when the trigger was predictable

The palliative-supportive care unit in a comprehensive cancer center as crossroad for patients' oncological pathway

Aim The aim of this study was to assess how an admission to an acute palliative-supportive care unit (APSCU), may influence the therapeutic trajectory of advanced cancer patients. Methods A consecutive sample of advanced cancer patients admitted to APCU was assessed. The following parameters were collected: patients demographics, including age, gender, primary diagnosis, marital status, and educational level, performance status and reasons for and kind of admission, data about care-givers, recent anticancer treatments, being on/off treatment or uncertain, the previous care setting, who proposed the admission to APSCU. Physical and psychological symptoms were evaluated at admission and at time of discharge. The use of opioids was also recorded. Hospital staying was also recorded. At time of discharge the parameters were recorded and a follow-up was performed one month after discharge. Results314 consecutive patients admitted to the APSCU were surveyed. Pain was the most frequent reason for admission. Changes of ESAS were highly significant, as well as the use of opioids and breakthrough pain medications (p lt;0.0005). A significant decrease of the number of [[ampi]]on therapy[[ampi]] patients was reported, and concomitantly a significant number of [[ampi]]offtherapy[[ampi]] patients increased. At one month follow-up, 38.9% patients were at home, 19.7% patients were receiving palliative home care, and 1.6% patients were in hospice. 68.5% of patients were still living. Conclusion Data of this study suggest that the APSCU may have a relevant role for managing the therapeutic trajectory of advanced cancer patients, limiting the risk of futile and aggressive treatment while providing an appropriate care setting

Diversity and Distribution of Freshwater Aerobic Anoxygenic Phototrophic Bacteria across a Wide Latitudinal Gradient

12 pages, 5 figures, 1 tableAerobic anoxygenic phototrophs (AAPs) have been shown to exist in numerous marine and brackish environments where they are hypothesized to play important ecological roles. Despite their potential significance, the study of freshwater AAPs is in its infancy and limited to local investigations. Here, we explore the occurrence, diversity and distribution of AAPs in lakes covering a wide latitudinal gradient: Mongolian and German lakes located in temperate regions of Eurasia, tropical Great East African lakes, and polar permanently ice-covered Antarctic lakes. Our results show a widespread distribution of AAPs in lakes with contrasting environmental conditions and confirm that this group is composed of different members of the Alpha- and Betaproteobacteria. While latitude does not seem to strongly influence AAP abundance, clear patterns of community structure and composition along geographic regions were observed as indicated by a strong macro-geographical signal in the taxonomical composition of AAPs. Overall, our results suggest that the distribution patterns of freshwater AAPs are likely driven by a combination of small-scale environmental conditions (specific of each lake and region) and large-scale geographic factors (climatic regions across a latitudinal gradient)This work was partly supported through the IGB Fellowship Program in Freshwater Science funded to IF. Sampling expedition to the African lakes was funded by the Spanish Ministry of Science and Innovation (CGL2010-11556-E). Antarctic samples were collected as part of the US NSF funded McMurdo Dry Valleys Long-Term Ecological Research Program (NSF-PLR 1115245). [...] HS work was supported by CNPq and FAPESP (Process: 2014/14139-3).Peer Reviewe