New developments in instrumentation at the W. M. Keck Observatory

The W. M. Keck Observatory continues to develop new capabilities in support of our science driven strategic plan which emphasizes leadership in key areas of observational astronomy. This leadership is a key component of the scientific productivity of our observing community and depends on our ability to develop new instrumentation, upgrades to existing instrumentation, and upgrades to supporting infrastructure at the observatory. In this paper we describe the as measured performance of projects completed in 2014 and the expected performance of projects currently in the development or construction phases. Projects reaching completion in 2014 include a near-IR tip/tilt sensor for the Keck I adaptive optics system, a new center launch system for the Keck II laser guide star facility, and NIRES, a near-IR Echelle spectrograph for the Keck II telescope. Projects in development include a new seeing limited integral field spectrograph for the visible wavelength range called the Keck Cosmic Web Imager, a deployable tertiary mirror for the Keck I telescope, upgrades to the spectrograph detector and the imager of the OSIRIS instrument, and an upgrade to the telescope control systems on both Keck telescopes

Tree growth and management in Ugandan agroforestry systems: effects of root pruning on tree growth and crop yield

Tree root pruning is a potential tool for managing below-ground competition when trees and crops are grown together in agroforestry systems. This study investigates its effects on growth and root distribution of Alnus acuminata (HB & K), Casuarina equisetifolia (L), Grevillea robusta (A. Cunn. ex R. Br), Maesopsis eminii (Engl.), and Markhamia lutea (Benth.) K. Schum. and on yield of adjacent crops in sub-humid Uganda. The trees were 3 years old at the commencement of the study, and most species were competing strongly with crops. Tree roots were pruned 41 months after planting by cutting and back-filling a trench to a depth of 0.3 m, at a distance of 0.3 m from the trees, on one side of the tree row. The trench was re-opened and roots re-cut at 50 and 62 months after planting. Effects on tree growth and root distribution were assessed over a 3 year period, and crop yield after the third root pruning at 62 months is reported here. Overall, root pruning had only a slight effect on tree growth: height growth was unaffected and diameter growth was reduced by only 4 %. A substantial amount of root re-growth was observed by 11 months after pruning. Tree species varied in the number and distribution of their roots, and Casuarina and Markhamia had considerably more roots per unit of trunk volume than the other tree species, especially in the surface soil layers. Casuarina and Maesopsis were the most competitive tree species with crops and Grevillea and Markhamia the least. Crop yield data provides strong evidence of the redistribution of root activity following root pruning, so that competition increased on the unpruned side of tree rows. Thus, one-sided root pruning will only be of use to farmers in a few circumstances. Key words: Alnus acuminata, Casuarina equisetifolia, Grevillea robusta, Maesopsis eminii, Markhamia lutea, root distribution, root functio

Failure of hospital employees to comply with smoke-free policy is associated with nicotine dependence and motives for smoking: A descriptive cross-sectional study at a teaching hospital in the United Kingdom

Abstract Background Smoke-free policy aims to protect the health of the population by reducing exposure to environmental tobacco smoke (ETS), and World Health Organisation (WHO) guidance notes that these policies are only successful if there is full and proper enforcement. We aimed to investigate the problem of resistance to smoking restrictions and specifically compliance with smoke-free policy. We hypothesised that an explanation for non-compliance would lie in a measurable difference between the smoking behaviours of compliant and non-compliant smokers, specifically that non-compliance would be associated with nicotine dependence and different reasons for smoking. Methods We conducted a questionnaire-based, descriptive, cross-sectional study of hospital employees. Seven hundred and four members of staff at Addenbrooke's Hospital, Cambridge, UK, completed the questionnaire, of whom 101 were smokers. Comparison between compliant and non-compliant smokers was made based on calculated scores for the Fagerström test and the Horn-Waingrow scale, and level of agreement with questions about attitudes. For ordinal data we used a linear-by-linear association test. For non-parametric independent variables we used the Mann-Whitney test and for associations between categorical variables we used the chi-squared test. Results The demographic composition of respondents corresponded with the hospital's working population in gender, age, job profile and ethnicity. Sixty nine smokers reported they were compliant while 32 were non-compliant. Linear-by-linear association analysis of the compliant and non-compliant smokers' answers for the Fagerström test suggests association between compliance and nicotine dependence (p = 0.049). Mann-Whitney test analysis suggests there is a statistically significant difference between the reasons for smoking of the two groups: specifically that non-compliant smokers showed habitual smoking behaviour (p = 0.003). Overall, compliant and non-compliant smokers did not have significantly different attitudes towards the policy or their own health. Conclusion We demonstrate that those who smoke in this setting in contravention to a smoke-free policy do so neither for pleasure (promotion of positive affect) nor to avoid feeling low (reduction of negative affect); instead it is a resistant habit, which has little or no influence on the smoker's mood, and is determined in part by chemical dependence

Dust and molecules in the Local Group galaxy NGC 6822. III. The first-ranked HII region complex Hubble V

We present maps of the first-ranked HII region complex Hubble V in the metal-poor Local Group dwarf galaxy NGC 6822 in the first four transitions of CO, the 158 micron transition of C+, the 21-cm line of HI, the Pa-beta line of HII, and the continuum at 21 cm and 2.2 micron wavelengths. We have also determined various integrated intensities, notably of HCO+ and near-IR H2 emission. Although Hubble X is located in a region of relatively strong HI emission, our mapping failed to reveal any significant CO emission from it. The relatively small CO cloud complex associated with Hubble V is comparable in size to the ionized HII region. The CO clouds are hot (Tkin) = 150 K) and have high molecular gas densities (n(H2) = 10**4 cm**-3) Molecular hydrogen probably extends well beyond the CO boundaries. C+ column densities are more than an order of magnitude higher than those of CO. The total mass of the complex is about 10**6 M(sun) and molecular gas account for more than half of this. The complex is excited by luminous stars reddened or obscured at visual, but apparent at near-infrared wavelengths. The total embedded stellar mass may account for about 10% of the total mass, and the mass of ionized gas for half of that. Hubble V illustrates that modest star formation efficiencies may be associated with high CO destruction efficiencies in low-metallicity objects. The analysis of the Hubble V photon-dominated region (PDR) confirms in an independent manner the high value of the CO-to-H2 conversion factor X found earlier, characteristic of starforming low-metallicity regions.Comment: Accepted for publication in A&

Genetic Identification and Mass Propagation of Economically Important Seaweeds

Seaweeds are a primary source of hydrocolloids, which can be processed into various food additives, cosmetics, and pharmaceuticals. The inability of current commercial seaweed farming projects to meet industrial demands is underscored by a plethora of challenges, which include the lack of high-quality germplasm with the desired cultural characteristics. This chapter describes the current trends in commercial seaweed production and the potential technological advances in production methods and genetic selection strategies, which can be applied to raise the productivity of seaweed farms. Molecular markers have become increasingly relevant to the selection of a diverse range of wild varieties for domestication, and this augurs well for strain identification. The development of high-density linkage maps based on molecular markers offers an avenue for the implementation of molecular breeding strategies based on quantitative trait loci (QTLs). Concurrently, productivity of existing varieties can be enhanced by the analysis of exogenous factors known to affect the growth and survival of tissue-cultured seedlings. The application of photobioreactors for tissue culture is another important development, which will be digressed upon. In addition to this, quality control which focuses on the comparison of chemical and physical qualities of the tissue-cultured and conventional cultivated seaweeds will become increasingly relevant to the development of industry standards for sustainable seaweed production to fulfill the increasing demands of seaweed-related industries

Sedimentation-consolidation of a double porosity material

This paper studies the sedimentation-consolidation of a double porosity material, such as lumpy clay. Large displacements and finite strains are accounted for in a multidimensional setting. Fundamental equations are derived using a phenomenological approach and non-equilibrium thermodynamics, as set out by Coussy [Coussy, Poromechanics, Wiley, Chichester, 2004]. These equations particularise to three non-linear partial differential equations in one dimensional context. Numerical implementation in a finite element code is currently being undertaken

Single-institution comparative study on the outcomes of salvage cryotherapy versus salvage robotic prostatectomy for radio-resistant prostate cancer

Background Although primary treatment of localized prostate cancer provides excellent oncologic control, some men who chose radiotherapy experience a recurrence of disease. There is no consensus on the most appropriate management of these patients after radiotherapy failure. In this single-institution review, we compare our oncologic outcome and toxicity between salvage prostatectomy and cryotherapy treatments. Methods From January 2004 to June 2013, a total of 23 salvage procedures were performed. Six of those patients underwent salvage prostatectomy while 17 underwent salvage cryotherapy by two high-volume fellowship-trained urologists. Patients being considered for salvage therapy had localized disease at presentation, a prostate-specific antigen (PSA) 10 years at recurrence, and a negative metastatic workup. Patients were followed to observe cancer progression and toxicity of treatment. Results Patients who underwent salvage cryotherapy were statistically older with a higher incidence of hypertension than our salvage prostatectomy cohort. With a mean follow up of 14.1 months and 7.2 months, the incidence of disease progression was 23.5% and 16.7% after salvage cryotherapy and prostatectomy, respectively. The overall complication rate was also 23.5% versus 16.7%, with the most frequent complication after salvage cryotherapy being urethral stricture and after salvage prostatectomy being severe urinary incontinence. There were no rectal injuries with salvage prostatectomy and one rectourethral fistula in the cohort after salvage cryotherapy. Conclusion While recurrences from primary radiotherapy for prostate cancer do occur, there is no consensus on its management. In our experience, salvage procedures were generally safe and effective. Both salvage cryotherapy and salvage prostatectomy allow for adequate cancer control with minimal toxicity

The little book of thermofluids (3rd edition)

Reference book for Engineering students

Probing isotopic ratios at z = 0.89: molecular line absorption in front of the quasar PKS 1830-211

With the Plateau de Bure interferometer, we have measured the C, N, O and S isotopic abundance ratios in the arm of a spiral galaxy with a redshift of 0.89. The galaxy is seen face-on according to HST images. Its bulge intercepts the line of sight to the radio-loud quasar PKS 1830-211, giving rise at mm wavelengths to two Einstein images located each behind a spiral arm. The arms appear in absorption in the lines of several molecules, giving the opportunity to study the chemical composition of a galaxy only a few Gyr old. The isotopic ratios in this spiral galaxy differ markedly from those observed in the Milky Way. The $^{17}$O/$^{18}$O and $^{14}$N/$^{15}$N ratios are low, as one would expect from an object too young to let low mass stars play a major role in the regeneration of the gas.Comment: accepted in A&

Searching for O2_2 in the SMC:Constraints on Oxygen Chemistry at Low Metallicities

We present a 39 h integration with the Odin satellite on the ground-state 118.75 GHz line of O2 towards the region of strongest molecular emission in the Small Magellanic Cloud. Our 3sigma upper limit to the O2 integrated intensity of <0.049 K km/s in a 9'(160 pc) diameter beam corresponds to an upper limit on the O2/H2 abundance ratio of <1.3E-6. Although a factor of 20 above the best limit on the O2 abundance obtained for a Galactic source, our result has interesting implications for understanding oxygen chemistry at sub-solar metal abundances. We compare our abundance limit to a variety of astrochemical models and find that, at low metallicities, the low O2 abundance is most likely produced by the effects of photo-dissociation on molecular cloud structure. Freeze-out of molecules onto dust grains may also be consistent with the observed abundance limit, although such models have not yet been run at sub-solar initial metallicities.Comment: 4 pages, accepted to A&A Letter