2,685 research outputs found
Sheltering-in-privilege: Silicon Valley
We suggest that one source of understanding entrepreneurial resilience and regional culture is through the denizens of Silicon Valley, and how they are handling crisis situations. We surveyed 119 entrepreneurs, investors, and large company executives based in Silicon Valley during the first COVID-19 lockdown period between April and May 2020. Our data show that the entrepreneurs perceived the situation as severe but were cautiously optimistic. They embraced creative destruction and took it as a way to change the status quo for the better. They predicted the new normal in the industry by acknowledging the critical role of science and technology. The ecosystem seems to enhance entrepreneurial resilience in the region through the social structures and entrepreneurial cultural value
Trends and Costs of External Electrical Bone Stimulators and Grafting Materials in Anterior Lumbar Interbody Fusion.
STUDY DESIGN: Retrospective review.
PURPOSE: To identify the trends in stimulator use, pair those trends with various grafting materials, and determine the influence of stimulators on the risk of revision surgery.
OVERVIEW OF LITERATURE: A large number of studies has reported beneficial effects of electromagnetic energy in healing long bone fractures. However, there are few clinical studies regarding the use of electrical stimulators in spinal fusion.
METHODS: We used insurance billing codes to identify patients with lumbar disc degeneration who underwent anterior lumbar interbody fusion (ALIF). Comparisons between patients who did and did not receive electrical stimulators following surgery were performed using logistic regression analysis, chi-square test, and odds ratio (OR) analysis.
RESULTS: Approximately 19% of the patients (495/2,613) received external stimulators following ALIF surgery. There was a slight increase in stimulator use from 2008 to 2014 (multi-level R2=0.08, single-level R2=0.05). Patients who underwent multi-level procedures were more likely to receive stimulators than patients who underwent single-level procedures (p0.05), except those in the multilevel ALIF+PLF cohort, wherein the patients who underwent stimulation had higher rates of revision surgery.
CONCLUSIONS: Concurrent PLF or multi-level procedures increased patients\u27 likelihood of receiving stimulators, however, the presence of comorbidities did not. Patients who received BMA plus autograft or allograft were more likely to receive stimulation. Patients with and without bone stimulators had similar rates of revision surgery
Lighthouses and Global Graph Stabilization: Active SLAM for Low-compute, Narrow-FoV Robots
Autonomous exploration to build a map of an unknown environment is a
fundamental robotics problem. However, the quality of the map directly
influences the quality of subsequent robot operation. Instability in a
simultaneous localization and mapping (SLAM) system can lead to poorquality
maps and subsequent navigation failures during or after exploration. This
becomes particularly noticeable in consumer robotics, where compute budget and
limited field-of-view are very common. In this work, we propose (i) the concept
of lighthouses: panoramic views with high visual information content that can
be used to maintain the stability of the map locally in their neighborhoods and
(ii) the final stabilization strategy for global pose graph stabilization. We
call our novel exploration strategy SLAM-aware exploration (SAE) and evaluate
its performance on real-world home environments.Comment: 7 pages, 7 figure
Passive Observer of Activities for Aging in Place Using a Network of RGB-D Sensors
Aging in place is a notion which supports the independent living of older adults at their own place of residence for as long as possible. To support this alternative living which can be in contrast to various other types of assisted living options, modes of monitoring technology need to be explored and studied in order to determine a balance between the preservation of privacy and adequacy of sensed information for better estimation and visualization of movements and activities. In this paper, we explore such monitoring paradigm on how a network of RGB-D sensors can be utilized for this purpose. This type of sensor offers both visual and depth sensing modalities from the scene where the information can be fused and coded for better protection of privacy. For this purpose, we introduce the novel notion of passive observer. This observer is only triggered by detecting the absence of movements of older adults in the scene. This is accomplished by classifying and localizing objects in the monitoring scene from both before and after the detection of movements. A deep learning tool is utilized for visual classification of known objects in the physical scene followed by virtual reality reconstructing of the scene where the shape and location of objects are recreated. Such reconstruction can be used as a visual summary in order to identify objects which were handled by an older adult in-between observation. The simplified virtual scene can be used, for example, by caregivers or monitoring personnel in order to assist in detecting any anomalies. This virtual visualization can offer a high level of privacy protection without having any direct visual access to the monitoring scene. In addition, using the scene graph representation, an automatic decision-making tool is proposed where spatial relationships between the objects can be used to estimate the expected activities. The results of this paper are demonstrated through two case studies
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An evidence-based review on the likely economic and environmental impact of genetically modified cereals and oilseeds for UK agriculture
An evidence-based review of the potential impact that the introduction of genetically-modified (GM) cereal and oilseed crops could have for the UK was carried out. The inter-disciplinary research project addressed the key research questions using scenarios for the uptake, or not, of GM technologies. This was followed by an extensive literature review, stakeholder consultation and financial modelling. The world area of canola, oilseed rape (OSR) low in both erucic acid in the oil and glucosinolates in the meal, was 34M ha in 2012 of which 27% was GM; Canada is the lead producer but it is also grown in the USA, Australia and Chile. Farm level effects of adopting GM OSR include: lower production costs; higher yields and profits; and ease of farm management. Growing GM OSR instead of conventional OSR reduces both herbicide usage and environmental impact.
Some 170M ha of maize was grown in the world in 2011 of which 28% was GM; the main producers are the USA, China and Brazil. Spain is the main EU producer of GM maize although it is also grown widely in Portugal. Insect resistant (IR) and herbicide tolerant (HT) are the GM maize traits currently available commercially. Farm level benefits of adopting GM maize are lower costs of production through reduced use of pesticides and higher profits. GM maize adoption results in less pesticide usage than on conventional counterpart crops leading to less residues in food and animal feed and allowing increasing diversity of bees and other pollinators. In the EU, well-tried coexistence measures for growing GM crops in the proximity of conventional crops have avoided gene flow issues. Scientific evidence so far seems to indicate that there has been no environmental damage from growing GM crops. They may possibly even be beneficial to the environment as they result in less pesticides and herbicides being applied and improved carbon sequestration from less tillage. A review of work on GM cereals relevant for the UK found input trait work on: herbicide and pathogen tolerance; abiotic stress such as from drought or salinity; and yield traits under different field conditions. For output traits, work has mainly focussed on modifying the nutritional components of cereals and in connection with various enzymes, diagnostics and vaccines. Scrutiny of applications submitted for field trial testing of GM cereals found around 9000 applications in the USA, 15 in Australia and 10 in the EU since 1996. There have also been many patent applications and granted patents for GM cereals in the USA for both input and output traits;an indication of the scale of such work is the fact that in a 6 week period in the spring of 2013, 12 patents were granted relating to GM cereals. A dynamic financial model has enabled us to better understand and examine the likely performance of Bt maize and HT OSR for the south of the UK, if cultivation is permitted in the future. It was found that for continuous growing of Bt maize and HT OSR, unless there was pest pressure for the former and weed pressure for the latter, the seed premia and likely coexistence costs for a buffer zone between other crops would reduce the financial returns for the GM crops compared with their conventional counterparts. When modelling HT OSR in a four crop rotation, it was found that gross margins increased significantly at the higher levels of such pest or weed pressure, particularly for farm businesses with larger fields where coexistence costs would be scaled down. The impact of the supply of UK-produced GM crops on the wider supply chain was examined through an extensive literature review and widespread stakeholder consultation with the feed supply chain. The animal feed sector would benefit from cheaper supplies of raw materials if GM crops were grown and, in the future, they might also benefit from crops with enhanced nutritional profile (such as having higher protein levels) becoming available. This would also be beneficial to livestock producers enabling lower production costs and higher margins. Whilst coexistence measures would result in increased costs, it is unlikely that these would cause substantial changes in the feed chain structure. Retailers were not concerned about a future increase in the amount of animal feed coming from GM crops.
To conclude, we (the project team) feel that the adoption of currently available and appropriate GM crops in the UK in the years ahead would benefit farmers, consumers and the feed chain without causing environmental damage. Furthermore, unless British farmers are allowed to grow GM crops in the future, the competitiveness of farming in the UK is likely to decline relative to that globally
Supporting Middle School Students in Tier 2 Math Labs: Instructional Strategies
Response to Intervention (RtI) has become a common support system for students; yet, no universal RtI model exists, especially for mathematics and specifically at the middle school level. This article focuses on a specific model for delivering Tier 2 mathematics supports and services at the middle school level: math labs. Evidence–based and research–supported interventions are discussed that support the delivery of Tier 2 services within a middle school math lab RtI structure. A fictionalized vignette, drawing from multiple actual cases, is presented to highlight the use of a Tier 2 math lab within a middle school setting
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