Experiments in the fertilization of a salt water pond

It has long been recognized that the biological productivity of the sea depends primarily upon the nutrition of the phytoplankton. The aim of these experiments was to study this basic process in the cycle of production by the artificial increase of those plant nutrients most likely to become limiting...

Experimental study of the phosphorus cycle in fertilized salt water

The rates at which phosphorus is (1) assimilated by phytoplankton, (2) released into solution from dead cells, and (3) regenerated to inorganic state, were measured in outdoor concrete tanks containing sea water fertilized with inorganic phosphate and nitrate. Bottles wrapped in black cloth and bottles exposed to the light were filled with the tank water and suspended in the tanks; the three rates in the P cycle were calculated from the observed changes in the concentrations of inorganic and particulate P in the bottles. The maximum recorded rates were: assimilation = 0.36 µg-at. P/L of sea water in the tanks/day; solution = 0.38 µg-at./L/day; regeneration = 0.13 µg-at./L/day. In 18 series of measurements, during which phytoplankton increases predominated over decreases, the following relations were observed between the rates of phosphorus transformations and the size and absolute change of size of the phytoplankton populations: (1) The rate of phosphorus assimilation was significantly correlated with the size of the phytoplankton standing crop and showed an even stronger dependence upon the increment of growth. (2) The rate at which particulate organic phosphorus was released into solution was intimately related to the size of the standing crop and was independent of th~ change in population size (which in most cases was an increase). (3) The regeneration of dissolved inorganic phosphate from dissolved organic phosphorus depended upon the phytoplankton standing crop and showed no relation to the change in population size. If attached algae were allowed to grow on the sides and bottom of the tanks, in less than one month they removed three-fourths of the added phosphate from the waterphytoplankton system. Where attached algae were largely prevented from growing, four-fifths of the phosphorus originally present was detected in the water at the end of four week

Abundance and growth of Venus mercenaria and Callocardia moorhuana in relation to the character of bottom sediments

The distribution patterns of Venus mercenaria and Callocardia morrhuana in Narragansett Bay are shown to be related to the character of the bottom. Venus is most abundant where the dominant sediments are fine, but its abundance in these sediments is strongly related to the presence of large particles such as shell and rocks as minor constituents of the substratum...

Selecting Energy Efficient Building Envelope Retrofits to Existing Department of Defense Building Using Value Focused Thinking

The Department of Defense (DoD) has hundreds of thousands of facilities in its inventory, which consume billions of BTUSs of energy per year. Much of that energy is used to heat and cool the facility, and a great deal of this energy is lost through the building envelope. While new military construction works towards energy efficiency, the majority of DoD facilities were built over forty years ago with little regard to energy efficiency, and it is these facilities that have the greatest potential for energy efficient building envelope retrofits. There are hundreds of various new building envelope technologies available to retrofit an existing building envelope, including window, roof, and wall technologies. This research investigated fifteen different building envelope technologies and found that many of them are feasible alternatives for DoD facilities. Value Focused Thinking (VFT) was the methodology used to objectively compare these new technologies and capture what Air Force decision makers value in regards to retrofitting older facilities with these new building envelope technologies. Data from three different Air Force bases and values from three different Air Force Civil Engineer Operations Flight Chiefs were used to evaluate these fifteen technologies, and the results show that the energy efficient window technologies have the highest potential for energy savings at each location. However, the research also shows that each of these technologies is a viable option and should always be considered when retrofitting an existing facility

Metronome-Cued Stepping in Place after Hemiparetic Stroke: Comparison of a One- and Two-Tone Beat

Hemiparetic gait is characterised by temporal asymmetry and variability, and these variables are improved by auditory cueing. Stepping in place incorporates aspects of gait and may be a useful tool for locomotor training. The aim of this pilot study was to investigate the use of a single-tone and dual-tone metronome to cue stepping in place after hemiparetic stroke. Eight participants completed an uncued baseline stepping condition and two cued stepping conditions utilising a single-tone and a dualtone metronome. Step times were determined from force plate data, and asymmetry and variability were calculated for the three conditions. Step time asymmetry was significantly reduced in the single-tone condition compared to baseline, and paretic step time variability was significantly reduced in both cued conditions.The single-tone metronome appeared to be preferred to the dual-tone metronome based on participant feedback.The results of this pilot study suggest that metronome cueing produces similar benefits on stepping in place to previously reported findings in walking. Further research on whether stepping in place to a metronome can be used for locomotor training is needed

Establishing gold standard approaches to rapid tranquillisation: a review and discussion of the evidence on the safety and efficacy of medications currently used

Background: Rapid tranquillisation is used when control of agitation, aggression or excitement is required. Throughout the UK there is no consensus over the choice of drugs to be used as first line treatment. The NICE guideline on the management of violent behaviour involving psychiatric inpatients conducted a systematic examination of the literature relating to the effectiveness and safety of rapid tranquillisation (NICE, 2005). This paper presents the key findings from that review and key guideline recommendations generated, and discusses the implications for practice of more recent research and information. Aims: To examine the evidence on the efficacy and safety of medications used for rapid tranquillisation in inpatient psychiatric settings. Method: Systematic review of current guidelines and phase III randomised, controlled trials of medication used for rapid tranquillisation. Formal consensus methods were used to generate clinically relevant recommendations to support safe and effective prescribing of rapid tranquillisation in the development of a NICE guideline. Findings: There is a lack of high quality clinical trial evidence in the UK and therefore a ‘gold standard’ medication regime for rapid tranquillisation has not been established. Rapid tranquillisation and clinical practice: The NICE guideline produced 35 recommendations on rapid tranquillisation practice for the UK, with the primary aim of calming the service user to enable the use of psychosocial techniques. Conclusions and implications for clinical practice: Further UK specific research is urgently needed that provides the clinician with a hierarchy of options for the clinical practice of rapid tranquillisation

Mechanism of activation of H2O2 by peroxidases: kinetic studies on a model system

AbstractKinetic studies on the peroxidase activity of microperoxidase-8 at pH 5.5–8.5 show that the rate is increased by raising the pH or by the presence of guanidinium ion. Comparison with published data on the peroxidases provides evidence that the enzyme activates H2O2 through the cooperative binding of H+ + HO−2 and suggests a role for the invariant distal Arg

1976 Base Data for the Dairy Market Policy Simulator

A.E. Res. 80-2

The structural and scaling properties of nearby galaxy clusters: I - The universal mass profile

We present the integrated mass profiles for a sample of ten nearby (z<=0.15), relaxed galaxy clusters, covering a temperature range of [2-9]keV, observed with XMM-Newton. The mass profiles were derived from the observed gas density and temperature profiles under the hypothesis of spherical symmetry and hydrostatic equilibrium. All ten mass profiles are well described by an NFW-type profile over the radial range from 0.01 to 0.5 R_200, where R_200 is the radius corresponding to a density contrast of 200 with respect to the critical density at the cluster redshift. A King model is inconsistent with these data. The derived concentration parameters and total masses are in the range c_200=4-6 and M_200=1.2 10^14-1.2 10^15 Msol, respectively. Our qualitative and quantitative study of the mass profile shape shows, for the first time, direct and clear observational evidence for the universality of the total mass distribution in clusters. The mass profiles scaled in units of R_200 and M_200 nearly coincide, with a dispersion of less than 15% at 0.1 R_200. The c_200--M_200 relation is consistent with the predictions of numerical simulations for a LCDM cosmology, taking into account the measurement errors and expected intrinsic scatter. Our results provide further strong evidence in favour of the Cold Dark Matter cosmological scenario and show that the dark matter collapse is well understood at least down to the cluster scale.Comment: 8 pages, 5 figures. Accepted for publication in A&