520 research outputs found

    An Evaluation of Unmanned Aircraft System (UAS) as a Practical Tool for Salt Marsh Restoration Monitoring, San Francisco Bay, CA

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    Salt marshes in the San Francisco Bay area provide essential ecosystem services from critical habitat to buffering coastal flooding and are the focus of substantial ecological restoration, necessitating improved restoration monitoring approaches. Metrics such as land cover classification, bare ground elevation, and vegetation height provide an understanding of the functionality and health of tidal wetlands. Unlike traditional monitoring methods, which rely on time and labor-intensive field surveys or macroscale remote sensing techniques, unmanned aircraft systems (UAS) provide site specific high spatial resolution data that is comparable to satellite and manned aircraft derived imagery. I compared published literature and provided primary data analysis to evaluate the ability for UAS to provide useful monitoring metrics for salt marsh restoration. I employ UAS derived point cloud data to analyze 3-dimensional (3D) data and find that UAS data can provide elevation and hydrological modeling in addition to vegetation height metrics. My comparative review findings suggest that UAS technologies can be deployed towards salt marsh monitoring using multiple approaches to increase overall accuracy of these collected data. Using basic visible spectrum data, I achieved an overall accuracy of 73% land cover classification, and with more powerful sensors and computing, upwards of 90% accuracy can be achieved. UAS provide a temporarily flexible way to collect data, providing restoration ecologists more options and freedom to target specific temporal environmental characteristics. With functional data acquisition capabilities and a greater flexibility in temporal resolution, UAS show promise as a practical tool for salt marsh restoration monitoring

    Statistical Evaluation of Evidence for Clonal Allelic Alterations in array-CGH Experiments

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    In recent years numerous investigators have conducted genetic studies of pairs of tumor specimens from the same patient to determine whether the tumors share a clonal origin. These studies have the potential to be of considerable clinical significance, especially in clinical settings where the distinction of a new primary cancer and metastatic spread of a previous cancer would lead to radically different indications for treatment. Studies of clonality have typically involved comparison of the patterns of somatic mutations in the tumors at candidate genetic loci to see if the patterns are sufficiently similar to indicate a clonal origin. More recently, some investigators have explored the use of array CGH for this purpose. Standard clustering approaches have been used to analyze the data, but these existing statistical methods are not suited to this problem due to the paired nature of the data, and the fact that there exists no “gold standard” diagnosis to provide a definitive determination of which pairs are clonal and which pairs are of independent origin. In this article we propose a new statistical method that focuses on the individual allelic gains or losses that have been identified in both tumors, and a statistical test is developed that assesses the degree of matching of the locations of the markers that indicate the endpoints of the allelic change. The validity and statistical power of the test is evaluated, and it is shown to be a promising approach for establishing clonality in tumor samples

    Dual Axis Solar Tracker With Automated Cleaning System

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    Photovoltaic panels are fundamental in the generation of renewable energy both on a local scale and a utility scale. The mounting systems for such panels can be costly, require large amounts of maintenance, and miss out on energy savings. Manual cleaning and single axis tracking systems leave more to be desired from such systems. In this paper, we propose, research, test and manufacture a two axes solar tracking system with integrated water cleaning to obtain the most energy savings possible from a single PV panel. Our work shows that two axis tracking combined with an automated cleaning system can provide more energy savings compared to a fixed panel system requiring manual cleaning. We have shown technical feasibility of a two axis tracking system as well as demonstrated simple design, testing, and construction of a water based cleaning system using a small water pump and PVC piping. As a result of such manufacturing and in order to improve efficiency, it is our future recommendation to integrate water and electrical home connections, create a customer experience mobile or web based application, and complete large scale long term testing

    Effects of a Parallel Magnetic Field on the Metal-Insulator Transition in a Dilute Two-Dimensional Electron System

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    The temperature dependence of conductivity σ(T)\sigma (T) of a two-dimensional electron system in silicon has been studied in parallel magnetic fields B. At B=0, the system displays a metal-insulator transition at a critical electron density nc(0)n_c(0), and dσ/dT>0d\sigma/dT >0 in the metallic phase. At low fields (Bâ‰Č2B\lesssim 2 T), ncn_c increases as nc(B)−nc(0)∝BÎČn_c(B) - n_c(0) \propto B^{\beta} (ÎČ∌1\beta\sim 1), and the zero-temperature conductivity scales as σ(ns,B,T=0)/σ(ns,0,0)=f(BÎČ/ÎŽn)\sigma (n_s,B,T=0)/\sigma (n_s,0,0)=f(B^{\beta}/\delta_n) (where ÎŽn=(ns−nc(0))/nc(0)\delta_n=(n_s-n_c(0))/n_c(0), and nsn_s is electron density) as expected for a quantum phase transition. The metallic phase persists in fields of up to 18 T, consistent with the saturation of ncn_c at high fields

    Extremely efficient clocked electron transfer on superfluid helium

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    Unprecedented transport efficiency is demonstrated for electrons on the surface of micron-scale superfluid helium filled channels by co-opting silicon processing technology to construct the equivalent of a charge-coupled device (CCD). Strong fringing fields lead to undetectably rare transfer failures after over a billion cycles in two dimensions. This extremely efficient transport is measured in 120 channels simultaneously with packets of up to 20 electrons, and down to singly occupied pixels. These results point the way towards the large scale transport of either computational qubits or electron spin qubits used for communications in a hybrid qubit system

    Reciprocal control in adaptive environments

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    Computing has become an established part of the built environment augmenting it to become adaptive. We generally assume that we control the adaptive environments we inhabit. Using an existing adaptive environment prototype, we conducted a controlled study testing how the reversal of control (where the environment attempts to influence the behaviour of the inhabitant) would affect participants. Most participants changed their respiratory behaviour in accordance with this environmental manipulation. Behavioural change occurred either consciously or unconsciously. We explain the two different paths leading participants to behavioural change: (1) We adapt the model of interbodily resonance, a process of bodily interaction observable between, for example, partners engaged in verbal dialogue, to describe the unconscious bodily response to subtle changes in the environment. (2) And we apply the model of secondary control, an adjustment of one’s own expectations to maintain the pretence of control, to describe conscious cognitive adaptation to the changing environment. We also discuss potential applications of our findings in therapeutic and other settings

    TOP2A and EZH2 Provide Early Detection of an Aggressive Prostate Cancer Subgroup.

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    Purpose: Current clinical parameters do not stratify indolent from aggressive prostate cancer. Aggressive prostate cancer, defined by the progression from localized disease to metastasis, is responsible for the majority of prostate cancer–associated mortality. Recent gene expression profiling has proven successful in predicting the outcome of prostate cancer patients; however, they have yet to provide targeted therapy approaches that could inhibit a patient\u27s progression to metastatic disease. Experimental Design: We have interrogated a total of seven primary prostate cancer cohorts (n = 1,900), two metastatic castration-resistant prostate cancer datasets (n = 293), and one prospective cohort (n = 1,385) to assess the impact of TOP2A and EZH2 expression on prostate cancer cellular program and patient outcomes. We also performed IHC staining for TOP2A and EZH2 in a cohort of primary prostate cancer patients (n = 89) with known outcome. Finally, we explored the therapeutic potential of a combination therapy targeting both TOP2A and EZH2 using novel prostate cancer–derived murine cell lines. Results: We demonstrate by genome-wide analysis of independent primary and metastatic prostate cancer datasets that concurrent TOP2A and EZH2 mRNA and protein upregulation selected for a subgroup of primary and metastatic patients with more aggressive disease and notable overlap of genes involved in mitotic regulation. Importantly, TOP2A and EZH2 in prostate cancer cells act as key driving oncogenes, a fact highlighted by sensitivity to combination-targeted therapy. Conclusions: Overall, our data support further assessment of TOP2A and EZH2 as biomarkers for early identification of patients with increased metastatic potential that may benefit from adjuvant or neoadjuvant targeted therapy approaches. ©2017 AACR
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