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Triboelectric nanogenerators (TENGs) are devices capable of effectively harvesting electrical energy from mechanical motion prevalent around us. With the goal of developing TENGs with a small environmental footprint, herein we present the potential of using rubber and paper as biological materials for constructing triboelectric nanogenerators. We explored the performance of these TENGs with various contact material combinations, electrode sizes, and operational frequencies. The optimally configured TENG achieved a maximum open circuit output voltage of over 30 V, and a short circuit current of around 3 µA. Additionally, this optimally configured TENG was capable of charging various capacitors and achieved a maximum power output density of 21 mW/m². This work demonstrates that biologically derived materials can be used as effective, sustainable, and low-cost contact materials for the development of triboelectric nanogenerators with minimal environmental footprint.

 

This paper is exploring the connection between human trafficking in the dark web. It also looks into the different variations as to how people are trafficked and who is more likely to be trafficked. The surveys that were conducted is to mainly see current knowledge of everyday people on what they personally knew about the connection between trafficking and the dark web. 

Advanced Persistent Threats (APTs) are professional, sophisticated threats that pose a serious concern to our technologically-dependent society. As these threats become more common, conventional response-driven cyberattack management needs to be substituted with anticipatory defense measures. Understanding adversarial behavior and movement is critical to improve our ability to proactively defend. This paper focuses on understanding adversarial movement and adaptation using a case study from a real-time cybersecurity exercise. Through multidisciplinary methodologies from social and hard sciences, this paper presents a mechanism to dissect cyberadversarial intrusion chains to unpack movement, and adaptations. 

Teachers’ situated knowledge of the class- room and teaching suggests that they can play an important role in promoting and supporting change in teaching practice even if they are not formally designated as leaders. We selected 32 secondary mathematics and science teachers and supported them in enriching their instructional practice and in becoming in structionally-focused teacher leaders. We describe the qualities we sought in teachers who were to become effective teacher leaders, and we share the ways in which we assessed those characteristics. We explain our rationale, instruments, and interview questions used in the selection of the teacher leaders. After four years, our teachers have served and continue to serve in numerous formal and informal leadership roles. We offer three recommendations to administrators for nurturing teacher leaders. 

Extensive experimental studies show that all major rock-forming elements (e.g., Si, Mg, Fe, Ca, Al, Na, K) dissolve in steam to a greater or lesser extent. We use these results to compute chemical equilibrium abundances of rocky-element-bearing gases in steam atmospheres equilibrated with silicate magma oceans. Rocky elements partition into steam atmospheres as volatile hydroxide gases (e.g., Si(OH)4, Mg(OH)2, Fe(OH)2, Ni(OH)2, Al(OH)3, Ca(OH)2, NaOH, KOH) and via reaction with HF and HCl as volatile halide gases (e.g., NaCl, KCl, CaFOH, CaClOH, FAl(OH)2) in much larger amounts than expected from their vapor pressures over volatile-free solid or molten rock at high temperatures expected for steam atmospheres on the early Earth and hot rocky exoplanets. We quantitatively compute the extent of fractional vaporization by defining gas/magma distribution coefficients and show that Earth's subsolar Si/Mg ratio may be due to loss of a primordial steam atmosphere. We conclude that hot rocky exoplanets that are undergoing or have undergone escape of steam-bearing atmospheres may experience fractional vaporization and loss of Si, Mg, Fe, Ni, Al, Ca, Na, and K. This loss can modify their bulk composition, density, heat balance, and interior structure. 

The selective use of seasonal precipitation by vegetation is critical to understanding the residence time and flow path of water in watersheds, yet there are limited datasets to test how climate alters these dynamics. Here, we use measurements of the seasonal cycle of tree ringO for two widespread conifer species in the Rocky Mountains of North America to provide a multi‐decadal depiction of the seasonal origins of forest water use. The results show that while the conifer tree stands had a dominant preference for use of snowmelt, there were multi‐annual periods over the last four decades when use of summer precipitation was preferential. Utilization of summer rain emerged during years with increased snowfall and tree growth, suggesting that summer rain enhanced the transpiration stream only during the periods of highest water use. We hypothesize this could be explained through shallowing of the root profile during wetter periods and/or through the influence of changing water table depths on the residence time of summer precipitation in the root zone. We suggest the tree ring proxy approach used here could be applied in other watersheds to provide critical insight into the temporal dynamics of plant water use that could not be inferred from short measurement campaigns. These data on the seasonal origins of forest water are critical for understanding forest vulnerability to drought, the processes that affect precipitation pathways and residence time in watersheds and the interpretation of tree ring proxy data.

 

Abstract The Iceland Greenland Seas Project (IGP) is a coordinated atmosphere–ocean research program investigating climate processes in the source region of the densest waters of the Atlantic meridional overturning circulation. During February and March 2018, a field campaign was executed over the Iceland and southern Greenland Seas that utilized a range of observing platforms to investigate critical processes in the region, including a research vessel, a research aircraft, moorings, sea gliders, floats, and a meteorological buoy. A remarkable feature of the field campaign was the highly coordinated deployment of the observing platforms, whereby the research vessel and aircraft tracks were planned in concert to allow simultaneous sampling of the atmosphere, the ocean, and their interactions. This joint planning was supported by tailor-made convection-permitting weather forecasts and novel diagnostics from an ensemble prediction system. The scientific aims of the IGP are to characterize the atmospheric forcing and the ocean response of coupled processes; in particular, cold-air outbreaks in the vicinity of the marginal ice zone and their triggering of oceanic heat loss, and the role of freshwater in the generation of dense water masses. The campaign observed the life cycle of a long-lasting cold-air outbreak over the Iceland Sea and the development of a cold-air outbreak over the Greenland Sea. Repeated profiling revealed the immediate impact on the ocean, while a comprehensive hydrographic survey provided a rare picture of these subpolar seas in winter. A joint atmosphere–ocean approach is also being used in the analysis phase, with coupled observational analysis and coordinated numerical modeling activities underway.