Eta Carinae -- Physics of the Inner Ejecta

Eta Carinae's inner ejecta are dominated observationally by the bright Weigelt blobs and their famously rich spectra of nebular emission and absorption lines. They are dense (n_e ~ 10^7 to 10^8 cm^-3), warm (T_e ~ 6000 to 7000 K) and slow moving (~40 km/s) condensations of mostly neutral (H^0) gas. Located within 1000 AU of the central star, they contain heavily CNO-processed material that was ejected from the star about a century ago. Outside the blobs, the inner ejecta include absorption-line clouds with similar conditions, plus emission-line gas that has generally lower densities and a wider range of speeds (reaching a few hundred km/s) compared to the blobs. The blobs appear to contain a negligible amount of dust and have a nearly dust-free view of the central source, but our view across the inner ejecta is severely affected by uncertain amounts of dust having a patchy distribution in the foreground. Emission lines from the inner ejecta are powered by photoionization and fluorescent processes. The variable nature of this emission, occurring in a 5.54 yr event cycle, requires specific changes to the incident flux that hold important clues to the nature of the central object.Comment: This is Chapter 5 in a book entitled: Eta Carinae and the Supernova Impostors, Kris Davidson and Roberta M. Humphreys, editors Springe

Detection of high-velocity material from the wind-wind collision zone of Eta Carinae across the 2009.0 periastron passage

We report near-IR spectroscopic observations of the Eta Carinae massive binary system during 2008-2009 using VLT/CRIRES. We detect a strong, broad absorption wing in He I 10833 extending up to -1900 km/s across the 2009.0 spectroscopic event. Archival HST/STIS ultraviolet and optical data shows a similar high-velocity absorption (up to -2100 km/s) in the UV resonance lines of Si IV 1394, 1403 across the 2003.5 event. UV lines from low-ionization species, such as Si II 1527, 1533 and C II 1334, 1335, show absorption up to -1200 km/s, indicating that the absorption with v from -1200 to -2100 km/s originates in a region markedly faster and more ionized than the nominal wind of the primary star. Observations obtained at the OPD/LNA during the last 4 spectroscopic cycles (1989-2009) also display high-velocity absorption in He I 10833 during periastron. Based on the OPD/LNA dataset, we determine that material with v < -900 km/s is present in the phase range 0.976 < phi < 1.023 of the spectroscopic cycle, but absent in spectra taken at phi < 0.947 and phi > 1.049. Therefore, we constrain the duration of the high-velocity absorption to be 95 to 206 days (or 0.047 to 0.102 in phase). We suggest that the high-velocity absorption originates from shocked gas in the wind-wind collision zone, at distances of 15 to 45 AU in the line-of-sight to the primary star. Using 3-D hydrodynamical simulations of the wind-wind collision zone, we find that the dense high-velocity gas is in the line-of-sight to the primary star only if the binary system is oriented in the sky so that the companion is behind the primary star during periastron, corresponding to a longitude of periastron of omega ~ 240 to 270 degrees. We study a possible tilt of the orbital plane relative to the Homunculus equatorial plane and conclude that our data are broadly consistent with orbital inclinations in the range i=40 to 60 degrees.Comment: 18 pages, 15 figures, accepted for publication in A&A; high-resolution PDF version available also at http://www.mpifr.de/staff/jgroh/etacar.htm

Converting simulated total dry matter to fresh marketable yield for field vegetables at a range of nitrogen supply levels

Simultaneous analysis of economic and environmental performance of horticultural crop production requires qualified assumptions on the effect of management options, and particularly of nitrogen (N) fertilisation, on the net returns of the farm. Dynamic soil-plant-environment simulation models for agro-ecosystems are frequently applied to predict crop yield, generally as dry matter per area, and the environmental impact of production. Economic analysis requires conversion of yields to fresh marketable weight, which is not easy to calculate for vegetables, since different species have different properties and special market requirements. Furthermore, the marketable part of many vegetables is dependent on N availability during growth, which may lead to complete crop failure under sub-optimal N supply in tightly calculated N fertiliser regimes or low-input systems. In this paper we present two methods for converting simulated total dry matter to marketable fresh matter yield for various vegetables and European growth conditions, taking into consideration the effect of N supply: (i) a regression based function for vegetables sold as bulk or bunching ware and (ii) a population approach for piecewise sold row crops. For both methods, to be used in the context of a dynamic simulation model, parameter values were compiled from a literature survey. Implemented in such a model, both algorithms were tested against experimental field data, yielding an Index of Agreement of 0.80 for the regression strategy and 0.90 for the population strategy. Furthermore, the population strategy was capable of reflecting rather well the effect of crop spacing on yield and the effect of N supply on product grading

Impact of heteroresistance on treatment outcomes of people with drug-resistant TB

BackgroundPoor treatment outcomes among people with drug-resistant TB (DR-TB) are a major concern. Heteroresistance (presence of susceptible and resistant Mycobacterium tuberculosis in the same sample) has been identified in some people with TB, but its impact on treatment outcomes is unknown.MethodsWe used targeted deep sequencing to identify mutations associated with DR-TB and heteroresistance in culture samples of 624 people with DR-TB. We evaluated the association between heteroresistance and time to unfavorable treatment outcome using Cox proportional hazards regression.ResultsThe proportion of drug-resistant isolates with a known mutation conferring resistance was lower for streptomycin (45.2%) and second-line injectables (79.1%) than for fluoroquinolones (86.7%), isoniazid (93.2%) and rifampin (96.5%). Fifty-two (8.3%) had heteroresistance, and it was more common for fluoroquinolones (4.6%) than rifampin (2.2%), second-line injectables (1.4%), streptomycin (1.7%), or isoniazid (1.3%). There was no association between heteroresistance and time to unfavorable outcome among people with multidrug-resistant TB (adjusted hazard ratio [aHR] 1.74, 95% CI 0.39-7.72) or pre-extensively DR-TB (aHR 0.65, 95% CI 0.24-1.72).ConclusionsHeteroresistance was relatively common (8.3%) among people with DR-TB in the Philippines. However, we found insufficient evidence to demonstrate an impact on unfavorable treatment outcomes

Cost of TB prevention and treatment in the Philippines in 2017.

BACKGROUND: The Philippines aims to accelerate TB reduction through the provision of universally accessible and affordable services. The objectives of this paper are to estimate the costs of TB services and interventions using a health systems´ perspective, and to explore cost differences in service delivery via primary care facilities or hospitals.METHODS: Data were collected from a multi-stage stratified random sampling of 28 facilities in accordance with Global Health Cost Consortium costing standards and analysis tools. Unit costs (in US$) estimated using top-down (TD) and bottom-up (BU) approaches, are summarised following Value TB reporting standards and by broad facility type.RESULTS: Cost of delivering 32 TB services and eight interventions varied by costing method and delivery platform. Average BU costs ranged from US$0.38 for treatment support visits, US$2.5 for BCG vaccination, US$19.48 for the Xpert® MTB/RIF test to US$3,677 for MDR-TB treatment using the long regimen. Delivering TB care in hospitals was generally more costly than in primary care facilities, except for TB prevention in children and MDR-TB treatment using the long regimen.CONCLUSION: Comprehensive costing data for TB care in the Philippines are now available to aid in the design, planning, and prioritisation of delivery models to End TB

Automated food drying system using labview as controller and user-interface platform

An automated food drying system was designed, created and analyzed. LabVIEW® graphical programming environment was used to as a user interface with controls and indicators to manipulate the dryer temperature and servo motor- driven air exhaust and intake vent openings. NI USB-6218 Multifunction Data Acquisition Hub was the device in charge to gather data and control the system. The system involved digital and analog sensing as well as external light indicators that indicates processing status for monitoring from a distant point. Wet bulb and dry bulb temperatures inside the dryer were measured and utilized to determine the relative humidity inside the dryer through computation using steam table and psychrometric chart for checking. The sensor calibration showed 5.56oC and 5.35oC offset value for dry bulb and wet bulb thermometers respectively. The warm-up responses of the dryer were evaluated by getting the slope of the cooling curve at different vent configurations and it was observed that the most efficient way to warm up the dryer was to close all vents with average slopes of 0.0103oC/s for heater 1, 0.0334oC/s for heater 2 and 0.0621oC/s for both heaters. It was determined that loading the chamber with sample takes a longer time to warm up. Unshielded long thermocouple wires, grounding and uneven blow of air introduced small errors in temperature measurements which were ignored since the precision of data is not crucial for the current application. System evaluation showed offset values of 0.1oC/s in the temperature measurements. Temperature data collected were based on real time measurements from two sensors. One temperature data was based from the average of 300 data points at a rate of 300 samples per measure. Tests showed that the thermostat can maintain temperature with ±0.4365oC stability which qualified the ±4oC requirement. Vent opening angles were set from 0 degree (fully closed) to 96 degrees (fully open). Solid state relays and wire performance for the fan and heaters were stable after hours of operation. The vent motors and controller were observed to have 30 seconds (max) response time per motor when the opening angle was changed which causes a maximum of ±3.6oC instability in the temperature. The functions of the workstation’s input devices, such as the mouse and numeric pad were maximized by utilizing them in changing knob, slide and digital control values

Automated food drying system using labview as controller and user-interface platform.

An automated food drying system was designed, created and analyzed. LabVIEW* graphical programming environment was used to as a user interface with controls and indicators to manipulate the dryer temperature and servo motor-driven air exhaust and intake vent openings. NI USB-6218 Multifunction Data Acquisition Hub was the device in charge to gather data and control the system The system involved digital and analog sensing as well as external light indicators that indicates processing status for monitoring from a distant point. Wet bulb and dry bulb temperatures inside the dryer were measured and utilized to determine the relative humidity inside the dryer through computation using steam table and psychrometric chart for checking. The sensor calibration showed 5.56°C and 5.35°C offset value for dry bulb and wet bulb thermometers respectively. The warm-up responses of the dryer were evaluated by getting the slope of the cooling curve at different vent configurations and it was observed that the most efficient way to warm up the dryer was to close all vents with average slopes of 0.0103°C/s for heater 1, 0.0334°C/s for heater 2 and 0.0621°C/s for both heaters. It was determined that loading the chamber with sample takes a longer time to warm up. Unshielded long thermocouple wires, grounding and uneven blow of air introduced small errors in temperature measurements which were ignored since the precision of data is not crucial for the current application. System evaluation showed offset values of 0.1°C/s in the temperature measurements. Temperature data collected were based on real time measurements from two sensors. One temperature data was based from the average of 300 data points at a rate of 300 samples per measure. Tests showed that the thermostat can maintain temperature with ±0.4365°C stability which qualified the ±4°C requirement. Vent opening angles were set from 0 degree (fully closed) to 96 degrees (fully open). Solid state relays and wire performance for the fan and heaters were stable after hours of operation. The vent motors and controller were observed to have 30 seconds (max) response time per motor when the opening angle was changed which causes a maximum of ±3.6°C instability in the temperature. The functions of the workstation\u27s input devices, such as the mouse and numeric pad were maximized by utilizing them in changing knob, slide and digital control values

Engaging Nursing Students in a Culture of Integrity

BACKGROUND: In order to become safe, effective professionals, nursing students must have a working knowledge of academic and professional integrity principles. However, nursing students have knowledge gaps in these areas, which may lead to unethical practices postgraduation. Inconsistencies in faculty enforcement of integrity principles may lead to student confusion and further student risk. METHOD: An interactive online integrity course was designed to address knowledge gaps related to academic and professional integrity. Course engagement occurred through self-reflection, quizzes, and a commitment statement. The pilot course was deployed to all nursing faculty and staff for feedback and approval. RESULTS: Of the 38 faculty and staff invited, 20 participated in the course. Based on feedback, course adjustments were made to address navigation, quiz clarity, and content. The online integrity course received full faculty approval. CONCLUSION: An interactive online integrity course is one option to support student engagement in and assimilation to a culture of integrity