Oregon State University

About: Oregon State University is a education organization based out in Corvallis, Oregon, United States. It is known for research contribution in the topics: Population & Gene. The organization has 28192 authors who have published 64044 publications receiving 2634108 citations. The organization is also known as: Oregon Agricultural College & OSU.

Role of Light Availability and Dispersal in Exotic Plant Invasion along Roads and Streams in the H. J. Andrews Experimental Forest, Oregon

Abstract: We examined the roles of dispersal mechanism, a biological barrier; light availability, an environ- mental barrier; and level of disturbance, a physical barrier, in explaining the spatial patterns of exotic plant species along road and stream segments in a forest landscape in the western Cascade Range of Oregon (U.S.A). The presence or absence of 21 selected exotic plant species and light levels were observed along 0.3- to 1.0-km transects within four habitat types. Each habitat represented a different level of disturbance: high-use roads, low-use roads, abandoned roads, and streams in the H. J. Andrews Experimental Forest. Nearly 300 50 3 2-m sampling units were surveyed along five transects in each habitat type. We used ordination (nonmetric multidimensional scaling) and logistic regression to analyze data. All of the nearly 200 sampling units along roads with high and low levels of vehicle traffic contained at least one exotic plant species, and some con- tained as many as 14. Streams that were most recently disturbed by floods 20-30 years ago and abandoned spur roads with no traffic for 20-40 years also had numerous exotic species. Roads and streams apparently serve multiple functions that enhance exotic species invasion in this landscape: they act as corridors or agents for dispersal, provide suitable habitat, and contain reservoirs of propagules for future episodes of in- vasion. Species-specific dispersal mechanisms, habitat characteristics, and disturbance history each explain some, but not all, of the patterns of exotic species invasion observed in this study.

Lidar Remote Sensing of Aboveground Biomass in Three Biomes

Abstract: Estimation of the amount of carbon stored in forests is a key challenge for understanding the global carbon cycle, one which remote sensing is expected to help address. However, direct estimation of carbon storage in moderate to high biomass forests is difficult for conventional optical and radar sensors. Lidar (light detection and ranging) instruments measure the vertical structure of forests and thus hold great promise for remotely sensing the quantity and spatial organization of forest biomass. In this study, we compare the relationships between lidar-measured canopy structure and coincident field measurements of aboveground biomass at sites in the temperate deciduous, temperate coniferous, and boreal coniferous biomes. A single “simplified” regression for all three sites is compared with equations derived for each site individually. The simplified equation explains 84% of variance in aboveground biomass (p<0.0001) and shows no statistically significant bias in its predictions for any individual site.

Unsupervised Video Summarization with Adversarial LSTM Networks

Abstract: This paper addresses the problem of unsupervised video summarization, formulated as selecting a sparse subset of video frames that optimally represent the input video. Our key idea is to learn a deep summarizer network to minimize distance between training videos and a distribution of their summarizations, in an unsupervised way. Such a summarizer can then be applied on a new video for estimating its optimal summarization. For learning, we specify a novel generative adversarial framework, consisting of the summarizer and discriminator. The summarizer is the autoencoder long short-term memory network (LSTM) aimed at, first, selecting video frames, and then decoding the obtained summarization for reconstructing the input video. The discriminator is another LSTM aimed at distinguishing between the original video and its reconstruction from the summarizer. The summarizer LSTM is cast as an adversary of the discriminator, i.e., trained so as to maximally confuse the discriminator. This learning is also regularized for sparsity. Evaluation on four benchmark datasets, consisting of videos showing diverse events in first-and third-person views, demonstrates our competitive performance in comparison to fully supervised state-of-the-art approaches.

What's Going on with Young People Today? The Long and Twisting Path to Adulthood

Abstract: Richard Settersten and Barbara Ray examine the lengthening transition to adulthood over the past several decades, as well as the challenges the new schedule poses for young people, families, and society. The authors begin with a brief history of becoming an adult, noting that the schedule that youth follow to arrive at adulthood changes to meet the social realities of each era. For youth to leave home at an early age during the 1950s, for example, was "normal" because opportunities for work were plentiful and social expectations of the time reinforced the need to do so. But the prosperity that made it possible for young adults of that era to move quickly into adult roles did not last. The economic and employment uncertainties that arose during the 1970s complicated enormously the decisions that young adults had to make about living arrangements, educational investments, and family formation. The authors next take a closer look at changes in the core timing shifts in the new transition-the lengthening time it now takes youth to leave home, complete school, enter the workforce, marry, and have children. They stress that today's new schedule for attaining independence leaves many families overburdened as they support their children for an extended period. The continued need to rely on families for financial assistance, the authors say, exacerbates the plight of young people from a variety of vulnerable backgrounds. It also raises complex questions about who is responsible for the welfare of young people and whether the risks and costs newly associated with the early adult years should be absorbed by markets, by families, or by governments. Settersten and Ray stress that the longer transition to adulthood strains not only families but also the institutions that have traditionally supported young Americans in making that transition-such as residential colleges and universities, community colleges, military service, and national service programs. They emphasize the need to strengthen existing social institutions and create new ones to reflect more accurately the realities of a longer and more complex passage into adult life.