661 research outputs found
Institutional Ambition and the Decline of Congress
According to James Madison\u27s theory of separated powers, ambition among members of each branch of government should prevent one branch from usurping the powers of another. However, this is hard to reconcile with the modern trend of congressional decline and executive aggrandizement. This paper takes a historical and developmental approach to argue that the informal changes to the American Constitution that took place throughout the 20th century combined with the modern trends of polarization and weak citizenship have left Congress weak and Madison\u27s theory ineffective
Titration
This model is meant to represent what is going on during a titration at the particle leve
Efficacy of a Conservative Weight Loss Program in the Long-Term Management of Chronic Upper Airway Obstruction
Objective. Obesity is a significant contributor to oxygen demand and dynamic airway obstruction. The objective of the current study is to determine the long-term success of conservative measures directed toward weight reduction on airway management without respect to specific airway disease etiology. Methods. Patients with chronic airway obstruction secondary anatomic lesions or obstructive sleep apnea were recruited and followed prospectively. Demographics, initial and final weights, diagnosis, and followup information were recorded. Patients were referred to a registered dietician, provided counseling, and started on a weight-loss regimen. Outcome measures were change in body mass index (BMI) and rate of decannulation from weight loss alone. Results. Of fourteen patients, ten remained tracheostomy-dependent and four had high-grade lesions with the potential for improvement in oxygen demand and dynamic airway collapse with weight loss. The mean follow up period was 25 months. The mean change in BMI was an increase of 1.4 kg/m2
per patient. Conclusions. Conservative measures alone were not effective in achieving weight reduction in the population studied. This may be due to comorbid disease and poor compliance. The promise of decannulation was an insufficient independent motivator for weight loss in this study. Although the theoretical benefits of weight loss support its continued recommendation, the long-term success rate of conservative measures is low. More aggressive facilitated interventions including pharmacotherapy or bariatric surgery should be considered early in the course of treating airway disease complicated by obesity
Saving Electrical Energy in Commercial Buildings
With the commercial and institutional building sectors using approximately 29% and 34% of all electrical energy consumption in Canada and the United States, respectively, saving electrical energy in commercial and institutional buildings represents an important chal- lenge for both the environment and the energy consumer. Concurrently, a rapid decline in the cost of microprocessing and communication has enabled the profileration of smart me- ters, which allow a customer to monitor energy usage every hour, 15 minutes or even every minute. Algorithmic analysis of this stream of meter readings would allow 1) a building operator to predict the potential cost savings from implemented energy savings measures without engaging the services of an expensive energy expert; and 2) an energy expert to quickly obtain a high-level understanding of a building’s operating parameters without a time-consuming and expensive site visit. This thesis develops an algorithm that takes as input a stream of building meter data and outputs a building’s operating parameters. This output can be used directly by an energy expert to assess a building’s performance; it can also be used as input to other algorithms or systems, such as systems that 1) predict the cost savings from a change in these operating parameters; 2) benchmark a portfolio of building; 3) create baseline models for measurement and verification programs; 4) detect anomalous building behaviour; 5) provide novel data visualization methods; or 6) assess the applicability of demand response programs on a given building. To illustrate this, we show how operating parameters can be used to estimate potential energy savings from energy savings measures and predict building energy consumption. We validate our ap- proach on a range of commercial and institutional buildings in Canada and the United States; our dataset consists of 10 buildings across a variety of geographies and industries and comprises over 21 years of meter data. We use K-fold cross-validation and benchmark our work against a leading black-box prediction algorithm; our model offers comparable prediction accuracy while being far less complex
The bacterial symbiont Phaeobacter inhibens Shapes the life history of its algal host emiliania huxleyi
© 2018 Bramucci, Labeeuw, Orata, Ryan, Malmstrom and Case. Marine microbes form host-associated biofilm communities that are shaped by complex interactions between bacteria and their host. The roseobacter Phaeobacter inhibens exploits both symbiotic and pathogenic niches while interacting with its microalgal host Emiliania huxleyi. During co-cultivation over extended periods with E. huxleyi, we show that P. inhibens selectively kills two host cell types, the diploid calcifying strain and the haploid flagellated strain. Meanwhile, various non-calcifying diploid strains are resistant to this pathogen or the pathogen is avirulent to this cell type. This differential pathogenesis has the potential of dramatically altering the composition of E. huxleyi blooms, which are typically dominated by the roseobacter-susceptible calcifying strain. This cell type makes calcite plates, which are an important sink in the marine carbon cycle and forms part of the marine paleobotanic record. P. inhibens kills the haploid cells, which have been proposed as critical to the survival of the algae, as they readily escape both eukaryotic predation and viral infection. Consequently, bacteria such as P. inhibens could influence E. huxleyi's life history by selective pathogenesis, thereby altering the composition of cell types within E. huxleyi populations and its bloom-bust lifestyle
Tracking the Fine Scale Movements of Fish using Autonomous Maritime Robotics: A Systematic State of the Art Review
This paper provides a systematic state of the art review on tracking the fine scale movements of fish with the use of autonomous maritime robotics. Knowledge of migration patterns and the localization of specific species of fish at a given time is vital to many aspects of conservation. This paper reviews these technologies and provides insight into what systems are being used and why. The review results show that a larger amount of complex systems that use a deep learning techniques are used over more simplistic approaches to the design. Most results found in the study involve Autonomous Underwater Vehicles, which generally require the most complex array of sensors. The results also provide insight into future research such as methods involving swarm intelligence, which has seen an increase in use in recent years. This synthesis of current and future research will be helpful to research teams working to create an autonomous vehicle with intentions to track, navigate or survey
The pharmacokinetics of continuous subcutaneous levodopa/carbidopa infusion: Findings from the ND0612 clinical development program
BACKGROUND: While treatment with levodopa remains the cornerstone of Parkinson\u27s disease (PD) management, chronic oral therapy is often associated with the development of motor complications, that correlate to fluctuating levodopa plasma concentrations, limiting its clinical utility. Continuous infusion is considered to be the optimal delivery route for treating PD patients with motor fluctuations, but current infusion systems require invasive surgery. Subcutaneous infusion of (SC) levodopa has the potential to provide a better tolerated and more convenient route of continuous levodopa delivery. ND0612 is in development as a combination product providing continuous levodopa/carbidopa via a minimally invasive, subcutaneous delivery system for PD patients experiencing motor response fluctuations. We present pharmacokinetic results from a series of studies that analyzed plasma concentrations after SC levodopa delivery with ND0612 to inform the clinical development program.
METHODS: We performed a series of six Phase I and II studies to characterize the pharmacokinetics of levodopa and carbidopa derived from ND0612 infusion with/without adjunct oral therapy of the same ingredients. These studies were conducted in healthy volunteers and in PD patients experiencing motor response fluctuations while on their current levodopa therapy regimen.
RESULTS: Taken together, the results demonstrate dose-proportionality dependent on rate of subcutaneous levodopa infusion leading to stable and sustained plasma concentrations of levodopa. Subcutaneous infusion of ND0612 administered with oral levodopa/carbidopa maintained near-constant, therapeutic levodopa plasma concentrations, thereby avoiding the troughs in levodopa plasma concentrations that are associated with OFF time in PD. The data generated in this series of studies also confirmed that a levodopa/carbidopa dose ratio of 8:1 would be the most reasonable choice for ND0612 development.
CONCLUSIONS: This series of clinical pharmacokinetic studies have demonstrated that ND0612, administered continuously with a levodopa concentration of 60 mg/ml combined with carbidopa 7.5 mg/ml, and complemented with oral levodopa/carbidopa, is suitable for 24 h continuous administration in patients with PD. The stable plasma concentrations of levodopa achieved predict utility of ND0612 as a parenteral formulation for achieving clinically useful delivery of levodopa for PD patients
CASTER - a concept for a Black Hole Finder Probe based on the use of new scintillator technologies
The primary scientific mission of the Black Hole Finder Probe (BHFP), part of
the NASA Beyond Einstein program, is to survey the local Universe for black
holes over a wide range of mass and accretion rate. One approach to such a
survey is a hard X-ray coded-aperture imaging mission operating in the 10--600
keV energy band, a spectral range that is considered to be especially useful in
the detection of black hole sources. The development of new inorganic
scintillator materials provides improved performance (for example, with regards
to energy resolution and timing) that is well suited to the BHFP science
requirements. Detection planes formed with these materials coupled with a new
generation of readout devices represent a major advancement in the performance
capabilities of scintillator-based gamma cameras. Here, we discuss the Coded
Aperture Survey Telescope for Energetic Radiation (CASTER), a concept that
represents a BHFP based on the use of the latest scintillator technology.Comment: 12 pages; conference paper presented at the SPIE conference "UV,
X-Ray, and Gamma-Ray Space Instrumentation for Astronomy XIV." To be
published in SPIE Conference Proceedings, vol. 589
CASTER: a scintillator-based black hole finder probe
The primary scientific mission of the Black Hole Finder Probe (BHFP), part of the NASA Beyond Einstein program, is to survey the local Universe for black holes over a wide range of mass and accretion rate. One approach to such a survey is a hard X-ray coded-aperture imaging mission operating in the 10-600 keV energy band, a spectral range that is considered to be especially useful in the detection of black hole sources. The development of new inorganic scintillator materials provides improved performance (for example, with regards to energy resolution and timing) that is well suited to the BHFP science requirements. Detection planes formed with these materials coupled with a new generation of readout devices represent a major advancement in the performance capabilities of scintillator-based gamma cameras. Here, we discuss the Coded Aperture Survey Telescope for Energetic Radiation (CASTER), a concept that represents a BHFP based on the use of the latest scintillator technology
Effects of Dietary or Supplementary Micronutrients on Sex Hormones and IGF-1 in Middle and Older Age: A Systematic Review and Meta-Analysis
Observational research suggests that micronutrients may be protective for sarcopenia, a key health issue during ageing, potentially via effects on hormone synthesis and metabolism. We aimed to carry out a systematic review of RCTs investigating effects of increasing dietary or supplemental micronutrient intake on sex hormones and IGF-1 in individuals aged 45 years or older. We searched MEDLINE, EMBASE and Cochrane databases for RCTs reporting the effects of different micronutrients (vitamins A, C, D, or E; carotenoids; iron; copper; zinc; magnesium; selenium; and potassium) on sex hormones or IGF-1. Of the 26 RCTs identified, nine examined effects of vitamin D, nine of multi-nutrients, four of carotenoids, two of selenium, one of zinc, and one of vitamin E. For IGF-1 increasing vitamin D (MD: -0.53 nmol/L, 95% CI: -1.58, 0.52), multi-nutrients (MD: 0.60 nmol/L, 95% CI 􀀀1.12 to 2.33) and carotenoids (MD -1.32 nmol/L; 95% CI -2.76 to 0.11) had no significant effect on circulating concentrations. No significant effects on sex hormones of other micronutrients were found, but data were very limited. All trials had significant methodological limitations making effects of micronutrient supplementation on sex hormones unclear. Further high quality RCTs with physiological doses of micronutrients in people with low baseline intakes or circulating concentrations, using robust methodology, are required to assess effects of supplementation adequately
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