Control-oriented modelling of wind direction variability

Wind direction variability significantly affects the performance and lifetime of wind turbines and wind farms. Accurately modelling wind direction variability and understanding the effects of yaw misalignment are critical towards designing better wind turbine yaw and wind farm flow controllers. This review focuses on control-oriented modelling of wind direction variability, which is an approach that aims to capture the dynamics of wind direction variability for improving controller performance over a complete set of farm flow scenarios, performing iterative controller development and/or achieving real-time closed-loop model-based feedback control. The review covers various modelling techniques, including large eddy simulations (LESs), data-driven empirical models, and machine learning models, as well as different approaches to data collection and pre-processing. The review also discusses the different challenges in modelling wind direction variability, such as data quality and availability, model uncertainty, and the trade-off between accuracy and computational cost. The review concludes with a discussion of the critical challenges which need to be overcome in control-oriented modelling of wind direction variability, including the use of both high- and low-fidelity models

Mega Tsunami of the World Oceans: Chevron Dune Formation, Micro-Ejecta, and Rapid Climate Change as the Evidence of Recent Oceanic Bolide Impacts

This paper deals with the physical and environmental effects resulting from oceanic impacts by sizable comets, and the rates and risks associated with such cosmic impacts. Specifically, we investigate two sets of probable oceanic impact events that occurred within the last 5,000 years, one in the Indian Ocean about 2800 BC, and the other in the Gulf of Carpentaria (Australia) about AD 536. If validated, they would be the most energetic natural catastrophes occurring during the middle-to-late Holocene with large-scale environmental and historical human effects and consequences. The physical evidence for these two impacts consists of several sets of data: (1) remarkable depositional traces of coastal flooding in dunes (chevron dunes) found in southern Madagascar and along the coast of the Gulf of Carpentaria, (2) the presence of crater candidates (29-km Burckle crater about 1,500 km southeast of Madagascar which dates to within the last 6,000 years and 18-km Kanmare and 12-km Tabban craters with an estimated age of AD 572±86 in the southeast corner of the Gulf of Carpentaria), and (3) the presence of quench textured magnetite spherules and nearly pure carbon spherules, teardrop-shaped tektites with trails of ablation, and vitreous material found by cutting-edge laboratory analytical techniques in the upper-most layer of core samples close to the crater candidates. Although some propose a wind-blown origin for V-shaped chevron dunes that are widely distributed around the coastlines of the Indian Ocean and in the Gulf of Carpentaria, we have evidence in favor of their mega tsunami formation. In southern Madagascar we have documented evidence for tsunami wave run-up reaching 205 m above sea-level and penetrating up to 45 km inland along the strike of the chevron axis. Subtly the orientation of the dunes is not aligned to the prevailing wind direction, but to the path of refracted mega-tsunami originating from Burckle impact crater. The results of our study show that substantive oceanic comet impacts not only have occurred more recently than modeled by astrophysicists, but also that they have profoundly affected Earth’s natural systems, climate, and human societies. If validated, they could potentially lead to a major paradigm shift in environmental science by recognizing the role of oceanic impacts in major climate downturns during the middle-to-late Holocene that have been well documented already by different techniques (tree-ring anomalies, ice-, lake- and peat bog-cores)

Final report for the network authentication investigation and pilot.

New network based authentication mechanisms are beginning to be implemented in industry. This project investigated different authentication technologies to see if and how Sandia might benefit from them. It also investigated how these mechanisms can integrate with the Sandia Two-Factor Authentication Project. The results of these investigations and a network authentication path forward strategy are documented in this report

Design and initial deployment of the wireless local area networking infrastructure at Sandia National Laboratories.

A major portion of the Wireless Networking Project at Sandia National Laboratories over the last few years has been to examine IEEE 802.11 wireless networking for possible use at Sandia and if practical, introduce this technology. This project team deployed 802.11a, b, and g Wireless Local Area Networking at Sandia. This report examines the basics of wireless networking and captures key results from project tests and experiments. It also records project members thoughts and designs on wireless LAN architecture and security issues. It documents some of the actions and milestones of this project, including pilot and production deployment of wireless networking equipment, and captures the team's rationale behind some of the decisions made. Finally, the report examines lessons learned, future directions, and conclusions

Role of LAG-3 in Regulatory T Cells

AbstractRegulatory T cells (Tregs) limit autoimmunity but also attenuate the magnitude of antipathogen and antitumor immunity. Understanding the mechanism of Treg function and therapeutic manipulation of Tregs in vivo requires identification of Treg-selective receptors. A comparative analysis of gene expression arrays from antigen-specific CD4+ T cells differentiating to either an effector/memory or a regulatory phenotype revealed Treg-selective expression of LAG-3, a CD4-related molecule that binds MHC class II. Antibodies to LAG-3 inhibit suppression by induced Tregs both in vitro and in vivo. Natural CD4+CD25+ Tregs express LAG-3 upon activation, which is significantly enhanced in the presence of effector cells, whereas CD4+CD25+ Tregs from LAG-3−/− mice exhibit reduced regulatory activity. Lastly, ectopic expression of LAG-3 on CD4+ T cells significantly reduces their proliferative capacity and confers on them suppressor activity toward effector T cells. We propose that LAG-3 marks regulatory T cell populations and contributes to their suppressor activity

A multidisciplinary stroke clinic for outpatient care of veterans with cerebrovascular disease

Background: Managing cerebrovascular risk factors is complex and difficult. The objective of this program evaluation was to assess the effectiveness of an outpatient Multidisciplinary Stroke Clinic model for the clinical management of veterans with cerebrovascular disease or cerebrovascular risk factors. Methods: The Multidisciplinary Stroke Clinic provided care to veterans with cerebrovascular disease during a one-half day clinic visit with interdisciplinary evaluations and feedback from nursing, health psychology, rehabilitation medicine, internal medicine, and neurology. We conducted a program evaluation of the clinic by assessing clinical care outcomes, patient satisfaction, provider satisfaction, and costs. Results: We evaluated the care and outcomes of the first consecutive 162 patients who were cared for in the clinic. Patients had as many as six clinic visits. Systolic and diastolic blood pressure decreased: 137.2 ± 22.0 mm Hg versus 128.6 ± 19.8 mm Hg, P = 0.007 and 77.9 ± 14.8 mm Hg versus 72.0 ± 10.2 mm Hg, P = 0.004, respectively as did low-density lipoprotein (LDL)-cholesterol (101.9 ± 23.1 mg/dL versus 80.6 ± 25.0 mg/dL, P = 0.001). All patients had at least one major change recommended in their care management. Both patients and providers reported high satisfaction levels with the clinic. Veterans with stroke who were cared for in the clinic had similar or lower costs than veterans with stroke who were cared for elsewhere. Conclusion: A Multidisciplinary Stroke Clinic model provides incremental improvement in quality of care for complex patients with cerebrovascular disease at costs that are comparable to usual post-stroke care

Androgen ablation mitigates tolerance to a prostate/prostate cancer-restricted antigen

SummaryTo understand the T cell response to prostate cancer, we created transgenic mice that express a model antigen in a prostate-restricted pattern and crossed these animals to TRAMP mice that develop spontaneous prostate cancer. Adoptive transfer of prostate-specific CD4 T cells shows that, in the absence of prostate cancer, the prostate gland is mostly ignored. Tumorigenesis allows T cell recognition of the prostate gland—but this recognition is tolerogenic, resulting in abortive proliferation and ultimately in hyporesponsiveness at the systemic level. Androgen ablation (the most common treatment for metastatic prostate cancer) was able to mitigate this tolerance—allowing prostate-specific T cells to expand and develop effector function after vaccination. These results suggest that immunotherapy for prostate cancer may be most efficacious when administered after androgen ablation