Cooling processes in deep, temperate lakes: A review with examples from two lakes in British Columbia

The cooling period in deep, temperate lakes includes the breakdown of the seasonal thermocline, isothermal overturn as the lake cools through 4°C, and winter restratification. The first part of this paper is taken up with a review of the relatively few studies on the seasonal cooling of lakes...

Local Wisdom Found in Mangongkal Holi Tradition

Mangongkal Holi is known as the highest level of tradition on Batak Toba daily life practices. Previously, this tradition was done by those limited families for the reasons of funding and its complicated management. But nowadays, the practice of mangongkal holi tradition is more rarely to be found; eventhough there are many local wisdom implicitly impressed on it. This study is part of the first writer’s dissertation, entitled Tradisi Mangongkal Holi pada Masyarakat Batak Toba (Mangongkal Holi Tradition in Batak Toba Society). This research was done in qualitative research, the data were collected through direct participatory observation, in-depth interviews with many batak toba informants (adat’s experts, practitioners and academicians/theologians), as well as audio-visual documentation. The data were analyzed by using Miles, and Huberman model; where data condensation, data display and data conclusion/verification were the three concurrent flows activities done to make sure the process of data analysis precisely on the track. The final conclusion of this research state that there were nine local wisdom found in mangongkal holi tradition, they are: thanksgiving, respect, humble/humility, blessings, responsibility, mutual cooperation, prays, concession in dialogue, and prestige; where all these local wisdom will be well-stored and longlasting while mangongkal holi tradition conserved through good and acceptable design of recommended revitalization model. The writers believe that there are still many solutions to solve the problems of funding, such as: down-grading the level of ceremony, or unifying more individual saring-sarings in a mangongkal holi ceremony.     Keywords: Mangongkal Holi, Local Wisdom, Oral Tradition, Batak Toba

The Photophysical Properties of CdTe/ZnS Core/Shell Quantum Dots

The distinctive fluorescent properties of semiconductor nanocrystal quantum dots (QDs) make them advantageous for use in optoelectronic and biological applications. We report on experiments done to characterize the optical properties and the general photostability of CdTe QDs with varying ZnS shell thicknesses. Steady-state and time-resolved absorption and fluorescence spectroscopy measurements indicate that increasing the ZnS shell thickness results in longer absorption and emission wavelengths, increased quantum yield, and improved photostability.Faculty Sponsor: Dr. James J. Butler and Dr. David Corde

Architecture for Cognitive Networking within NASAs Future Space Communications Infrastructure

Future space mission concepts and designs pose many networking challenges for command, telemetry, and science data applications with diverse end-to-end data delivery needs. For future end-to-end architecture designs, a key challenge is meeting expected application quality of service requirements for multiple simultaneous mission data flows with options to use diverse onboard local data buses, commercial ground networks, and multiple satellite relay constellations in LEO, MEO, GEO, or even deep space relay links. Effectively utilizing a complex network topology requires orchestration and direction that spans the many discrete, individually addressable computer systems, which cause them to act in concert to achieve the overall network goals. The system must be intelligent enough to not only function under nominal conditions, but also adapt to unexpected situations, and reorganize or adapt to perform roles not originally intended for the system or explicitly programmed. This paper describes architecture features of cognitive networking within the future NASA space communications infrastructure, and interacting with the legacy systems and infrastructure in the meantime. The paper begins by discussing the need for increased automation, including inter-system collaboration. This discussion motivates the features of an architecture including cognitive networking for future missions and relays, interoperating with both existing endpoint-based networking models and emerging information-centric models. From this basis, we discuss progress on a proof-of-concept implementation of this architecture as a cognitive networking on-orbit application on the SCaN Testbed attached to the International Space Station

Moving from evidence-based medicine to evidence-based health.

While evidence-based medicine (EBM) has advanced medical practice, the health care system has been inconsistent in translating EBM into improvements in health. Disparities in health and health care play out through patients' limited ability to incorporate the advances of EBM into their daily lives. Assisting patients to self-manage their chronic conditions and paying attention to unhealthy community factors could be added to EBM to create a broader paradigm of evidence-based health. A perspective of evidence-based health may encourage physicians to consider their role in upstream efforts to combat socially patterned chronic disease

Arctic system on trajectory to new state

The Arctic system is moving toward a new state that falls outside the envelope of glacial-interglacial fluctuations that prevailed during recent Earth history. This future Arctic is likely to have dramatically less permanent ice than exists at present. At the present rate of change, a summer ice-free Arctic Ocean within a century is a real possibility, a state not witnessed for at least a million years. The change appears to be driven largely by feedback-enhanced global climate warming, and there seem to be few, if any processes or feedbacks within the Arctic system that are capable of altering the trajectory toward this “super interglacial” state

Superconducting aluminum heat switch with 3 nΩ\Omega equivalent resistance

Superconducting heat switches with extremely low normal state resistances are needed for constructing continuous nuclear demagnetization refrigerators with high cooling power. Aluminum is a suitable superconductor for the heat switch because of its high Debye temperature and its commercial availability in high purity. We have constructed a high quality Al heat switch whose design is significantly different than that of previous heat switches. In order to join the Al to Cu with low contact resistance, we plasma etched the Al to remove its oxide layer then immediately deposited Au without breaking the vacuum of the e-beam evaporator. In the normal state of the heat switch, we measured a thermal conductance of $8 T$ W/K$^2$ which is equivalent to an electrical resistance of 3 n$\Omega$ according to the Wiedemann-Franz law. In the superconducting state we measured a thermal conductance that is $2\times10^6$ times lower than that of the normal state at 50 mK