Searching for Earth-mass planets around α\alpha Centauri: precise radial velocities from contaminated spectra

This work is part of an ongoing project which aims to detect terrestrial planets in our neighbouring star system $\alpha$ Centauri using the Doppler method. Owing to the small angular separation between the two components of the $\alpha$ Cen AB binary system, the observations will to some extent be contaminated with light coming from the other star. We are accurately determining the amount of contamination for every observation by measuring the relative strengths of the H-$\alpha$ and NaD lines. Furthermore, we have developed a modified version of a well established Doppler code that is modelling the observations using two stellar templates simultaneously. With this method we can significantly reduce the scatter of the radial velocity measurements due to spectral cross-contamination and hence increase our chances of detecting the tiny signature caused by potential Earth-mass planets. After correcting for the contamination we achieve radial velocity precision of $\sim 2.5\,\mathrm{m\,s^{-1}}$ for a given night of observations. We have also applied this new Doppler code to four southern double-lined spectroscopic binary systems (HR159, HR913, HR7578, HD181958) and have successfully recovered radial velocities for both components simultaneously.Comment: accepted for publication in the International Journal of Astrobiology (published by Cambridge University Press); will appear in a revised form, subsequent to editorial input by Cambridge University Pres

A novel method of supplying nutrients permits predictable shoot growth and root: shoot ratios of pre-transplant bedding plants

BACKGROUND AND AIMS: Growth of bedding plants, in small peat plugs, relies on nutrients in the irrigation solution. The object of the study was to find a way of modifying the nutrient supply so that good-quality seedlings can be grown rapidly and yet have the high root : shoot ratios essential for efficient transplanting. METHODS: A new procedure was devised in which the concentrations of nutrients in the irrigation solution were modified during growth according to changing plant demand, instead of maintaining the same concentrations throughout growth. The new procedure depends on published algorithms for the dependence of growth rate and optimal plant nutrient concentrations on shoot dry weight Ws (g m–2), and on measuring evapotranspiration rates and shoot dry weights at weekly intervals. Pansy, Viola tricola ‘Universal plus yellow’ and petunia, Petunia hybrida ‘Multiflora light salmon vein’ were grown in four independent experiments with the expected optimum nutrient concentration and fractions of the optimum. Root and shoot weights were measured during growth. KEY RESULTS: For each level of nutrient supply Ws increased with time (t) in days, according to the equation {Delta}Ws/{Delta}t=K2Ws/(100+Ws) in which the growth rate coefficient (K2) remained approximately constant throughout growth. The value of K2 for the optimum treatment was defined by incoming radiation and temperature. The value of K2 for each sub-optimum treatment relative to that for the optimum treatment was logarithmically related to the sub-optimal nutrient supply. Provided the aerial environment was optimal, Rsb/Ro{approx}Wo/Wsb where R is the root : shoot ratio, W is the shoot dry weight, and sb and o indicate sub-optimum and optimum nutrient supplies, respectively. Sub-optimal nutrient concentrations also depressed shoot growth without appreciably affecting root growth when the aerial environment was non-limiting. CONCLUSION: The new procedure can predict the effects of nutrient supply, incoming radiation and temperature on the time course of shoot growth and the root : shoot ratio for a range of growing conditions

Case Study: Changing a Corporate Culture by Implementing a Compassionate Ministry Plan

As CEO of Ultimate Support Systems, Inc., Jim Dismore, one of the original founding officers of Wal-Mart, developed a compassionate ministry plan, which became an integral part of the company’s business plan. Each year the company set aside one percent of gross receipts as “first fruits” to be used for ministry purposes. A corporate ministry team, comprised of 14 employees, determined how the ministry funds would be used both internally and externally. The compassionate ministry plan helped transform the culture of the organization and enabled Ultimate Support Systems to become an industry leader while truly functioning as a “business in ministry.

Generational Shift and Drug Abuse in Older Americans

Since the problem of substance abuse by older adults began to receive serious professional attention, the focus has been almost exclusively on alcohol abuse. This reality is changing as the “baby boomers” age. We examined data from the National Household Survey on Drug Abuse (1985) and the National Survey on Drug Use and Health (2006) comparing nationwide prevalence of both legal and illicit drugs. Use of drugs by category varied over the study period; some showed little change (e.g., alcohol) while others showed marked increase (e.g., marijuana, cocaine). We found that the population of older Americans in 2006 contained greater proportions of persons who had used or continued to use illicit drugs than did older Americans in 1985. Gerontologists and geriatric services will increasingly encounter older Americans who use or abuse illicit drugs

A Brief History of Prohibition and Treatment Solutions for Substance Abusers

The predominant policy of prohibition (i.e. "War on Drugs") emerged in the early Twentieth Century. It has been expanded on since that time to become the primary thrust of drug policy in almost every nation today. We will examine how this came about and the ways in which it has contributed to the maltreatment of substance abuse disorders

From reaching every district to reaching every community: analysis and response to the challenge of equity in immunization in Cambodia

Background An international review of the Cambodian Expanded Programme on Immunization (EPI) in 2010 and other data show that despite immunization coverage increases and vaccine preventable diseases incidence reductions, inequities in access to immunization services exist. Utilizing immunization and health systems literature, analysis of global health databases and the EPI review findings, this paper examines the characteristics of immunization access and outcome inequities, and describes proposed longer-term strategic and operational responses to these problems. Findings The national programme has evolved from earlier central and provincial level planning to strengthening routine immunization coverage through the District level ‘Reaching Every District Strategy'. However, despite remarkable improvements, the review found over 20% of children surveyed were not fully immunized, primarily from communities where inequities of both access and impact persist. These inequities relate mainly to socio-economic exposures including wealth and education level, population mobility and ethnicity. To address these problems, a shift in strategic and operational response is proposed that will include (a) a re-focus of planning on facility level to detect disadvantaged communities, (b) establishment of monitoring systems to provide detailed information on community access and utilization, (c) development of communication strategies and health networks that enable providers to adjust service delivery according to the needs of vulnerable populations, and (d) securing financial, management and political commitment for ‘reaching every community'. Conclusions For Cambodia to achieve its immunization equity objectives and disease reduction goals, a shift of emphasis to health centre and community is needed. This approach will maximize the benefits of new vaccine introduction in the coming ‘Decade of Vaccines', plus potentially extend the reach of other life-saving maternal and child health interventions to the socially disadvantaged, both in Cambodia and in other countries with a similar level of developmen