4,909 research outputs found
Magnetic control assembly qualification model
Fabrication and testing of the magnetic control assembly (MCA) are summarized. The MCA was designed as an add-on unit for certain existing components of the Nimbus and ERTS attitude control system. The MCA system consists of three orthogonal electromagnets; a magnetometer probe capable of sensing external fields in the X, Y, and Z axes; and the control electronics. An operational description of the system is given along with all major drawings and photographs. Manufacturing and inspection procedures are outlined and a chronological list of events is included with the fabrication summary
Labor and Employment Law: Recent Developments - At-Will Termination of Employment Has Not Been Terminated
High Pressure Effects on Superconductivity in the beta-pyrochlore Oxides AOs2O6 (A=K, Rb, Cs)
Recently new pyrochlore oxides superconductors AOs2O6 (A=K,Rb,Cs) were found
and we measured the pressure dependence of magnetization up to 1.2 GPa in order
to deduce the pressure effect of Tc in the three beta-pyrochlore oxides. It is
found that the initial pressure dependence of Tc is positive for all the
compounds. Only KOs2O6 exhibits a saturation in Tc at 0.56 GPa and the downturn
at higher pressureComment: 7 pages, 2 figure
Cognitive Functions and Neurodevelopmental Disorders Involving the Prefrontal Cortex and Mediodorsal Thalamus
The mediodorsal nucleus of the thalamus (MD) has been implicated in executive functions
(such as planning, cognitive control, working memory, and decision-making) because of
its significant interconnectivity with the prefrontal cortex (PFC). Yet, whilst the roles of the
PFC have been extensively studied, how the MD contributes to these cognitive functions
remains relatively unclear. Recently, causal evidence in monkeys has demonstrated
that in everyday tasks involving rapid updating (e.g., while learning something new,
making decisions, or planning the next move), the MD and frontal cortex are working
in close partnership. Furthermore, researchers studying the MD in rodents have been
able to probe the underlying mechanisms of this relationship to give greater insights
into how the frontal cortex and MD might interact during the performance of these
essential tasks. This review summarizes the circuitry and known neuromodulators of
the MD, and considers the most recent behavioral, cognitive, and neurophysiological
studies conducted in monkeys and rodents; in total, this evidence demonstrates that
MD makes a critical contribution to cognitive functions. We propose that communication
occurs between the MD and the frontal cortex in an ongoing, fluid manner during rapid
cognitive operations, via the means of efference copies of messages passed through
transthalamic routes; the conductance of these messages may be modulated by other
brain structures interconnected to the MD. This is similar to the way in which other
thalamic structures have been suggested to carry out forward modeling associated with
rapid motor responding and visual processing. Given this, and the marked thalamic
pathophysiology now identified in many neuropsychiatric disorders, we suggest that
changes in the different subdivisions of the MD and their interconnections with the cortex
could plausibly give rise to a number of the otherwise disparate symptoms (including
changes to olfaction and cognitive functioning) that are associated with many different
neuropsychiatric disorders. In particular, we will focus here on the cognitive symptoms
of schizophrenia and suggest testable hypotheses about how changes to MD-frontal
cortex interactions may affect cognitive processes in this disorder
Administrative Law
The authors discuss recent developments in the field of administrative law in Florida. They discuss the constitutional and legal limitations imposed on the Florida legislature, administrative agencies and judiciary when involved in the administrative process. They then analyze the recent trend towards consolidation of proceedings among agencies and conclude that, if the trend is to gain any momentum, the legislature must redraft the regulatory schemes
Estimation of atmospheric total organic carbon (TOC) – paving the path towards carbon budget closure
The atmosphere contains a rich variety of reactive organic compounds,
including gaseous volatile organic carbon (VOCs), carbonaceous aerosols, and
other organic compounds at varying volatility. Here we present a novel and
simple approach to measure atmospheric non-methane total organic carbon (TOC)
based on catalytic oxidation of organics in bulk air to carbon dioxide. This
method shows little sensitivity towards humidity and near 100 % oxidation
efficiencies for all VOCs tested. We estimate a best-case hourly precision of
8 ppb C during times of low ambient variability in carbon dioxide, methane,
and carbon monoxide (CO). As proof of concept of this approach, we show
measurements of TOC + CO during August–September 2016 from a coastal
city in the southwest United Kingdom. TOC + CO was substantially
elevated during the day on weekdays (occasionally over 2 ppm C) as a result
of local anthropogenic activity. On weekends and holidays, with a mean
(standard error) of 102 (8) ppb C, TOC + CO was lower and showed much
less diurnal variability. TOC + CO was significantly lower when winds
were coming off the Atlantic Ocean than when winds were coming off land if we
exclude the weekday daytime. By subtracting the estimated CO from
TOC + CO, we constrain the mean (uncertainty) TOC in Atlantic-dominated
air masses to be around 23 (± ≥ 8) ppb C during this period. A
proton-transfer-reaction mass spectrometer (PTR-MS) was deployed at the same
time, detecting a large range of organic compounds (oxygenated VOCs, biogenic
VOCs, aromatics, dimethyl sulfide). The total speciated VOCs from the PTR-MS,
denoted here as Sum(VOC), amounted to a mean (uncertainty) of 12 (± ≤ 3) ppb C in marine air. Possible contributions from a number of known
organic compounds present in marine air that were not detected by the PTR-MS
are assessed within the context of the TOC budget. Finally, we note that the
use of a short, heated sample tube can improve the transmission of organics
to the analyzer, while operating our system alternately with and without a
particle filter should enable a better separation of semi-volatile and
particulate organics from the VOCs within the TOC budget. Future concurrent
measurements of TOC, CO, and a more comprehensive range of speciated VOCs
would enable a better characterization and understanding of
the atmospheric organic carbon budget.</p
The association of TB with HIV infection in Oromia Regional National State, Ethiopia in 2006/7
Background: Infection with Human Immunodeficiency Virus (HIV) is an established risk factor for tuberculosis infection. Population-based data on associations between HIV and tuberculosis (TB) can provide an epidemiological assessment of the impact of HIV infection on TB in environments where individual based data are difficult to collect.Method: We used an ecological study to assess the association between infection with HIV and tuberculosis in Oromia Region National State, Ethiopia in 2006/7.Result: The prevalence of HIV infection was significantly associated with the incidence of TB across the areas in Oromia region (r=0.69,
A novel hybrid teaching learning based multi-objective particle swarm optimization
How to obtain a good convergence and well-spread optimal Pareto front is still a major challenge for most meta-heuristic multi-objective optimization (MOO) methods. In this paper, a novel hybrid teaching learning based particle swarm optimization (HTL-PSO) with circular crowded sorting (CCS), named HTL-MOPSO, is proposed for solving MOO problems. Specifically, the new HTL-MOPSO combines the canonical PSO search with a teaching-learning-based optimization (TLBO) algorithm in order to promote the diversity and improve search ability. Also, CCS technique is developed to improve the diversity and spread of solutions when truncating the external elitism archive. The performance of HTL-MOPSO algorithm was tested on several well-known benchmarks problems and compared with other state-of-the-art MOO algorithms in respect of convergence and spread of final solutions to the true Pareto front. Also, the individual contributions made by the strategies of HTL-PSO and CCS are analyzed. Experimental results validate the effectiveness of HTL-MOPSO and demonstrate its superior ability to find solutions of better spread and diversity, while assuring a good convergence
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