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Informal trails created or perpetuated by visitors is a management challenge in many protected natural areas such as Yosemite National Park. This is a significant issue as informal trail networks penetrate and proliferate into protected landscapes and habitats, threatening ecological integrity, aesthetics, and visitor experiences. In order to develop effective strategies for addressing this problem under an adaptive management framework, indicators must be developed and monitoring protocol must be established to gather timely and relevant data about the condition, extent, and distribution of these undesired trail segments. This article illustrates a process of developing and evaluating informal trail indicators for meadows in Yosemite Valley. Indicator measures developed in past research were reviewed to identify their appropriateness for the current application. Information gaps in existing indicator measures were addressed by creating two new indices to quantify the degree of informal trailing based on its land fragmentation effects. The selected indicator measures were applied to monitoring data collected between 2006 and 2008. The selected measures and indices were evaluated for their ability to characterize informal trail impacts at site and landscape scales. Results demonstrate the utility of indicator measures in capturing different characteristics of the informal trail problem, though several metrics are strongly related to each other. The two fragmentation indices were able to depict fragmentation without being too sensitive to changes in one constituent parameter. This study points to the need for a multiparameter approach to informal trail monitoring and integration with other monitoring data. Implications for monitoring programs and research are discussed.

We review published studies on the demography and recruitment of California oak trees and focus on the widespread dominant species of the foothill woodlands, Quercus douglasii, Q. lobata, and Q. agrifolia, to ascertain the nature and strength of evidence for a decline in populations of these species. The vast majority of studies have been of short duration (less than three years), focused on the acorn and seedling life stages, and conducted at few locations within each species’ geographic range. We summarize the extensive body of research that has been conducted on the biological and physical factors that limit natural seedling recruitment of oaks. The oak “regeneration problem” has largely been inferred from current stand structure rather than by demographic analyses, which in part reflects the short-term nature of most oak research. When viewed over longer periods of time using field surveys or historical photos, the evidence for a regeneration problem in foothill oaks is mixed. Q. douglasii shows very limited seedling or sapling recruitment at present, but longer term studies do not suggest a decline in tree density, presumably because rare recruitment is sufficient to offset low rates of mortality of overstory individuals. Q. agrifolia appears to be stable or increasing in some areas, but decreasing in areas recently impacted by the disease Phytophthora ramorum. Evidence from the few available studies is more consistent in suggesting long-term declines in foothill populations of Q. lobata. Longterm monitoring, age structure analysis, and population models are needed to resolve the current uncertainty over the sustainability of oak woodlands in California.

Existing space suits use conventional wired sensors that collect very limited physiological data to monitor health of astronauts during missions. Adding more wired sensors would involve significant modifications and complexity to the suit. Deploying a wireless body area network (WBAN) is preferred and would provide a number of advantages such as flexibility in sensor complement and positioning. This paper investigates the performance of intra-space suit wireless propagation using a full-scale space suit model that is built with electrical properties similar to that of a real space suit. The performance is characterized by quantifying the channel path loss at three frequencies: 315 MHz, 433 MHz and 916 MHz. Using a top-hat monopole antenna that is conformal to the human body and excites dominant coaxial waveguide modes, we measure path loss associated with various transmitter-receiver locations. The results demonstrate that the intra-suit environment is quite conducive to radio propagation, although there are substantial differences in path loss for the different frequency bands.

Thin film multilayers have previously been introduced on multilayer low temperature cofired ceramic (LTCC), as well as initial thin film capacitors on LTCC. The ruggedness of a multipurpose Ti/Cu/Pt/Au stack for connectivity and RF conductivity has continued to benefit fabrication and reliability in state of-the-art modules, while the capacitors have followed the traditional Metal-Insulator-Metal (MIM) style. The full integration of thin film passives with thin film connectivity traces is presented. Certain passives, such as capacitors, require specifically tailored and separately patterned thin film (multi-)layers, including a dielectric. Different capacitance values are achieved by variation of both the insulator layer thickness and the active area of the capacitor. Other passives, such as filters, require only the conductor – a single thin film multilayer. This can be patterned from the same connectivity thin film material (Ti/Cu/Pt/Au), or a specially tailored thin film material (e.g. Ti/Cu/Au) can be deposited. Both versions are described, including process and integration details. Examples are discussed, ranging from patterning for maximum tolerances, to space and performance-optimized designs. Cross-sectional issues associated with integration are also highlighted in the discussion.