Isotopic composition of Murchison organic compounds: Intramolecular carbon isotope fractionation of acetic acid. Simulation studies of cosmochemical organic syntheses

Recently, in our laboratories, samples of Murchison acetic acid were decarboxylated successfully and the carbon isotopic composition was measured for the methane released by this procedure. These analyses showed significant differences in C-13/C-12 ratios for the methyl and carboxyl carbons of the acetic acid molecule, strongly suggesting that more than one carbon source may be involved in the synthesis of the Murchison organic compounds. On the basis of this finding, laboratory model systems simulating cosmochemical synthesis are being studied, especially those processes capable of involving two or more starting carbon sources

Heat capacity uncovers physics of a frustrated spin tube

We report on refined experimental results concerning the low-temperature specific heat of the frustrated spin tube material [(CuCl2tachH)3Cl]Cl2. This substance turns out to be an unusually perfect spin tube system which allows to study the physics of quasi-one dimensional antiferromagnetic structures in rather general terms. An analysis of the specific heat data demonstrates that at low enough temperatures the system exhibits a Tomonaga-Luttinger liquid behavior corresponding to an effective spin-3/2 antiferromagnetic Heisenberg chain with short-range exchange interactions. On the other hand, at somewhat elevated temperatures the composite spin structure of the chain is revealed through a Schottky-type peak in the specific heat located around 2 K. We argue that the dominating contribution to the peak originates from gapped magnon-type excitations related to the internal degrees of freedom of the rung spins.Comment: 4+ pages, 6 figure

Plant neighborhood effects on herbivory: Damage is both density and frequency dependent

© 2015 by the Ecological Society of America. Neighboring plants can affect the likelihood that a focal plant is attacked by herbivores. Both the density of conspecific neighbors (resource concentration or dilution effects) and the relative density of heterospecific neighbors (associational effects or effects of neighbor frequency) within the local neighborhood can affect herbivore load and plant damage. Understanding how these neighborhood effects influence processes such as plant competition or natural selection on plant resistance traits will require knowing how both plant density and frequency affect damage, but previous studies have generally confounded density and frequency effects. In this study, we independently manipulated the absolute density and frequency (i.e., relative density) of two plant species (Solanum carolinense and Solidago altissima) to characterize neighborhood composition effects on S. carolinense damage by herbivores, providing the first picture of how both density and frequency of neighbors influence damage in a single system. We found both a positive effect of S. carolinense density on S. carolinense damage (a resource concentration effect) and a nonlinear effect of S. altissima frequency on S. carolinense damage (associational susceptibility). If these types of patterns are common in nature, future studies seeking to understand neighborhood effects on damage need to incorporate both density and frequency effects and capture any nonlinear effects by selecting a range of values rather than focusing on only a pair of densities or frequencies. This type of data on neighborhood effects will allow us to understand the contribution of neighborhood effects to population-level processes such as competition, the evolution of plant resistance to herbivores, and yield gains in agricultural crop mixtures

EFFECT OF PERFORMANCE FEEDBACK DURING 6 WEEKS OF VELOCITY BASED SQUAT JUMP TRAINING

This study investigated the effect of instantaneous performance feedback (peak velocity) provided after each repetition of squat jump exercises in 13 professional rugby players. Players were randomly assigned to a feedback or non feedback group and completed three training sessions per week for six weeks. The relative magnitude (effect size) of the training effects for all performance tests were found to be small, except for 30m sprint which was moderate. The use of feedback was found to be possibly beneficial to increasing vertical jump, 10m and 20m sprint, likely to be beneficial to increasing horizontal jump and almost certainly beneficial to increasing 30m sprint. It is suggested that the provision of instantaneous feedback on movement velocity during resistance training sessions provides a greater potential for adaptation and larger training effects

Community Emergency Management During the 2005 Ambae Eruption, Vanuatu, SW Pacific.

No abstract availabl

Factors influencing the variation in GMS prescribing expenditure in Ireland

Background Pharmaceutical expenditure growth is a familiar feature in many Western health systems and is a real concern for policymakers. A state funded General Medical Services (GMS) scheme in Ireland experienced an increase in prescription expenditure of 414 % between 1998 and 2012. This paper seeks to explore the rationale for this growth by investigating the composition (Anatomical Therapeutic Chemical (ATC) Group level 1 & 5) and drivers of GMS drug expenditure in Ireland in 2012. Methods A cross-sectional study was carried out on the Health Service Executive-Primary Care Reimbursement Service (HSE-PCRS) population prescribing database (n = 1,630,775). Three models were applied to test the association between annual expenditure per claimant whilst controlling for age, sex, region, and the pharmacology of the drugs as represented by the main ATC groups. Results The mean annual cost per claimant was €751 (median = €211; SD = €1323.10; range = €3.27–€298,670). Age, sex, and regions were all significant contributory factors of expenditure, with gender having the greatest impact (β = 0.107). Those aged over 75 (β =1.195) were the greatest contributors to annual GMS prescribing costs. As regards regions, the South has the greatest cost increasing impact. When the ATC groups were included the impact of gender is diluted by the pharmacology of the products, with cardiovascular prescribing (ATC ‘C’) most influential (β = 1.229) and the explanatory power of the model increased from 40 % to 60 %. Conclusion Whilst policies aimed at cost containment (co-payment charges; generic substitution; reference pricing; adjustments to GMS eligibility) can be used to curtail expenditure, health promotional programs and educational interventions should be given equal emphasis. Also policies intended to affect physicians’ prescribing behaviour include guidelines, information (about price and less expensive alternatives) and feedback, and the use of budgetary restrictions could yield savings in Ireland and can be easily translated to the international context

Integrated digital/electric aircraft concepts study

The integrated digital/electrical aircraft (IDEA) is an aircraft concept which employs all electric secondary power systems and advanced digital flight control systems. After trade analysis, preferred systems were applied to the baseline configuration. An additional configuration, the alternate IDEA, was also considered. For this concept the design ground rules were relaxed in order to quantify additional synergistic benefits. It was proposed that an IDEA configuration and technical risks associated with the IDEA systems concepts be defined and the research and development required activities to reduce these risks be identified. The selected subsystems include: power generation, power distribution, actuators, environmental control system and flight controls systems. When the aircraft was resized, block fuel was predicted to decrease by 11.3 percent, with 7.9 percent decrease in direct operating cost. The alternate IDEA shows a further 3.4 percent reduction in block fuel and 3.1 percent reduction in direct operating cost

Possible Signature of Low Scale Gravity in Ultra High Enegry Cosmic Rays

We show that the existence of low scale gravity at TeV scale could lead to a direct production of photons with energies above 10^22 eV due to annihilation of ultra high energy neutrinos on relic massive neutrinos of the galactic halo. Air showers initialized in the terrestrial atmosphere by these ultra energetic photons could be collected in near future by the new generation of cosmic ray experiments.Comment: 5 pages, 3 figure

Automotive Stirling Engine Development Program

Development test activities on Mod I engines directed toward evaluating technologies for potential inclusion in the Mod II engine are summarized. Activities covered include: test of a 12-tube combustion gas recirculation combustor; manufacture and flow-distribution test of a two-manifold annular heater head; piston rod/piston base joint; single-solid piston rings; and a digital air/fuel concept. Also summarized are results of a formal assessment of candidate technologies for the Mod II engine, and preliminary design work for the Mod II. The overall program philosophy weight is outlined, and data and test results are presented