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This review revisits the traits thought to have contributed to the success of Indo-Pacific lionfish Pterois sp. as an invader in the western Atlantic Ocean and the worst-case scenario about their potential ecological effects in light of the more than 150 studies conducted in the past 5 years. Fast somatic growth, resistance to parasites, effective anti-predator defences and an ability to circumvent predator recognition mechanisms by prey have probably contributed to rapid population increases of lionfish in the invaded range. However, evidence that lionfish are strong competitors is still ambiguous, in part because demonstrating competition is challenging. Geographic spread has likely been facilitated by the remarkable capacity of lionfish for prolonged fasting in combination with other broad physiological tolerances. Lionfish have had a large detrimental effect on native reef-fish populations in the northern part of the invaded range, but similar effects have yet to be seen in the southern Caribbean. Most other envisaged direct and indirect consequences of lionfish predation and competition, even those that might have been expected to occur rapidly, such as shifts in benthic composition, have yet to be realized. Lionfish populations in some of the first areas invaded have started to decline, perhaps as a result of resource depletion or ongoing fishing and culling, so there is hope that these areas have already experienced the worst of the invasion. In closing, we place lionfish in a broader context and argue that it can serve as a new model to test some fundamental questions in invasion ecology.

Siberian hamsters (Phodopus sungorus) adapt to seasonal environmental conditions with marked changes in body mass, primarily in the form of adiposity. Winter-like conditions (e.g. short days) are sufficient to decrease body mass by approximately 30% in part via reductions in food intake. The neuroendocrine mechanisms responsible for these changes are not well understood, and homeostatic orexigenic/anorexigenic systems of the hypothalamus provide little explanation. We investigated the potential role of endocannabinoids, which are known modulators of appetite and metabolism, in mediating seasonal changes in energy balance. Specifically, we housed hamsters in long or short days for 0, 3, or 9 weeks and measured endocannabinoid levels in the hypothalamus, brainstem, liver and retroperitoneal white adipose tissue (RWAT). An additional group of males housed in short days for 25 weeks were also compared with long-day controls. Following 9 weeks in short days, levels of the endocannabinoid 2-arachidonoylglycerol (2-AG) were significantly elevated in RWAT and reduced in brainstem, although they returned to long-day levels by week 25 in short-day males that had cycled back to summer-like energy balance. Endocannabinoid levels in these tissues correlated significantly with adiposity and change in body mass. No photoperiodic changes were observed in the hypothalamus or liver; however, sex differences in 2-AG levels were found in the liver (males > females). We further tested the effects of CB(1) receptor signalling on ingestive behaviour. Five daily injections of CB(1) antagonist SR141716 significantly reduced food intake and body mass but not food hoarding. Although the CB(1) agonist arachidonyl-2-chloroethylamide did not appreciably affect either ingestive behaviour, body mass was significantly elevated following 2 days of injections. Taken altogether, these findings demonstrate that endocannabinoid levels vary with sex and photoperiod in a site-specific manner, and that altered signalling at CB(1) receptors affects energy balance in Siberian hamsters.

A novel 'crossed bevel' technique has been used for the investigation of the evolution of the altered layer that forms in a SiGe alloy under 8 keV O 2 + ion bombardment. Auger microscopy (MULSAM instrument) and low-energy ion beam bevelling (500 eV O 2 + ) were used to composition-depth profile a high-energy (8 keV O 2 + ) bevel that contained the complete history of the altered layer. The sample was transferred in vacuo from the bevelling instrument to the Auger microscope. The formation of a Ge-rich layer 15 nm below the altered layer surface, with an associated near-surface Ge depletion, was observed, consistent with previous measurements. The growth of a surface oxygen implant was also seen. The importance of the development of this technique is that it will enable the powerful multispectral chemometric capability of the MULSAM instrument to be applied to altered layer redistribution in the future.

The effect of initial high lime (7500 kg ha‐1), annual low lime (200 kg ha‐1 yr−1), and no lime (all with 200 kg ha−1 yr−1 superphosphate) and dicalcic superphosphate (400 kg ha−1 yr−1) was compared over six years under sheep grazing and mowing on a low rainfall (800 mm), low pH (5.4), phosphorus (P) responsive (Olsen P 5) Matapiro yellow‐grey earth (Duric palic) soil near Hastings, Hawke's Bay, New Zealand. High lime significantly increased pasture dry matter yield compared with other treatments in the first three years of the trial under both grazing and mowing. There were no differences in annual yield between the other treatments. The response to high lime in relation to no lime in the first 3 years was greater under grazing (21%) than mowing (12%). There was a greater number of legume plants per m2 under mowing than grazing. The increase in pasture yield from high lime in the grazing trial was because of an increase in grass rather than legume yield. Legume yield averaged over all years was ...

The depth resolution attainable in secondary ion mass spectroscopy (SIMS) depth profiling is shown to be greatly enhanced by the use of a floating ion gun, which is capable of delivering high primary ion currents (ca. 100 nA) at impact energies down to 250 eV. With specially grown, genuinely abrupt GaAs (Si,Al) delta layers and Si0.8Ge0.2/Si structures we have achieved SIMS profile full width at half maximum data as low as 1.3–2.2 nm (species dependent). Approximating the leading edges by exp(z/λL), where z is depth, we achieve λL (growth length) values ≊0.2 nm (i.e., 0.5 nm per decade of concentration). The trailing edge data, exp(−z/λT), exhibit the expected elemental dependence due to differences in preferential sputtering and more complex effects, with λT (decay length) ranging from 0.6 nm for Si to 1.8 nm for Al. This analytical performance, which can be obtained in combination with at least 1 part per million atomic elemental sensitivity, represents a major improvement in SIMS depth profiling capabi...

Siberian hamsters (Phodopus sungorus) adapt to seasonal environmental conditions with marked changes in body mass, primarily in the form of adiposity. Winter-like conditions (e.g. short days) are sufficient to decrease body mass by approximately 30% in part via reductions in food intake. The neuroendocrine mechanisms responsible for these changes are not well understood, and homeostatic orexigenic/anorexigenic systems of the hypothalamus provide little explanation. We investigated the potential role of endocannabinoids, which are known modulators of appetite and metabolism, in mediating seasonal changes in energy balance. Specifically, we housed hamsters in long or short days for 0, 3, or 9 weeks and measured endocannabinoid levels in the hypothalamus, brainstem, liver and retroperitoneal white adipose tissue (RWAT). An additional group of males housed in short days for 25 weeks were also compared with long-day controls. Following 9 weeks in short days, levels of the endocannabinoid 2-arachidonoylglycerol (2-AG) were significantly elevated in RWAT and reduced in brainstem, although they returned to long-day levels by week 25 in short-day males that had cycled back to summer-like energy balance. Endocannabinoid levels in these tissues correlated significantly with adiposity and change in body mass. No photoperiodic changes were observed in the hypothalamus or liver; however, sex differences in 2-AG levels were found in the liver (malesfemales). We further tested the effects of CB(1) receptor signalling on ingestive behaviour. Five daily injections of CB(1) antagonist SR141716 significantly reduced food intake and body mass but not food hoarding. Although the CB(1) agonist arachidonyl-2-chloroethylamide did not appreciably affect either ingestive behaviour, body mass was significantly elevated following 2 days of injections. Taken altogether, these findings demonstrate that endocannabinoid levels vary with sex and photoperiod in a site-specific manner, and that altered signalling at CB(1) receptors affects energy balance in Siberian hamsters.

Colorcurve (D65/1964) and Coloroid (C/1931) notations of the 558 OSA-UCS atlas samples are presented in two tables. One table provides the Colorcurve and Coloroid notations for the 424 regular samples; the other for the 134 near-neutral (half-step) samples. Colorcurve notations are derived from the OSA-UCS aim points, and Coloroid notations are derived from colorimetric data of the OSA-UCS samples contained in MacAdam's copy of the OSA-UCS colour atlas.

This article presents an evaluation of the deviation of the Colorcurve atlas samples from their designated aim points. Sample deviations are evaluated in terms of hue, chroma, and lightness. In addition, the deviation of the Colorcurve samples from their respective aim points are graphically represented for eighteen lightness levels, Comparison is provided with NCS, DIN, and OSA-UCS atlas sample deviation.

Details of an expanded and improved computer program for the interconversion of colour notations are presented. This article describes the inclusion of the Colorcurve, SCA 2541, and HunterLab systems, expansion of the DIN and RAL implements, extension of the NCS aim point database, improvements to the OSA-UCS and Coloroid conversion algorithms, a direct spectral curve input facility, and the inclusion of CIELAB, CIELUV, HunterLab, CMC[1:1], FMC-1, and FMC-2 colourdifference formulas. © 1992 John Wiley & Sons, Inc.

NCS (C/1931) and DIN (C/1931 and D65/1964) notations of the 558 OSA-UCS atlas samples are presented in two tables. One table provides the NCS and DIN notations for the 424 regular samples; the other for the 134 near-neutral (half-step) samples.

Low birth weight (LBW) followed by accelerated postnatal growth is associated with increased risk of developing age-associated diseases such as type 2 diabetes. Gestational protein restriction in rats causes LBW, beta-cell dysfunction, and reduced longevity. These effects may be mediated by accelerated cellular aging. This study tested the hypothesis that LBW followed by rapid postnatal catch-up growth leads to islet telomere shortening through alterations in antioxidant defense capacity, stress/senescence marker proteins, and DNA repair mechanisms at the gene expression level. We used our rat model of gestational protein restriction (recuperated offspring) and control offspring. Southern blotting revealed shorter (P

This article describes a further investigation into the accuracy of the samples that comprise the NCS colour atlas. Earlier research has demonstrated that the NCS atlas samples are, on average, more inaccurate than the samples that comprise other comparable colour atlases. The present work identifies areas of the NCS colour atlas containing coloured samples that significantly deviate from their intended aim points.

A computer program has been developed that converts between the notations of the Munsell, OSA-UCS, NCS, DIN, and Coloroid colour order systems and the CIE, CIELAB, and CIELUV colour specification systems. The intention of this article is to outline the development of this program and its structure. Particular attention is given to the accuracy of the program and its associated databases.

The term ‘data model’ is used to describe the conceptual view of how data which purports to model reality is arranged in a computer system. A ‘data structure’ is the logical view, and a ‘file structure’ is the actual physical arrangement of the data. Spatial data, as used in geographic information systems, gives rise to particular problems in deriving suitable data models and structures because of the diverse sources and applications of the data. This paper discusses some of these problems and puts forward some pragmatic solutions.

In 1985 a research program was instigated to determine the feasibility and desirability of developing a computer based colour notation conversion program. Results indicated that the development of such a program covering the Munsel, NCS, DIN, OSA-UCS, Coloroid, CIELAB and CIELUV colour specification systems for use as a research tool was both feasible and desirable. The program was completed early in 1989 and this is the first of a number of articles that uses this program as a research tool. The colour notation conversion program has been used to evaluate the accuracy of the samples which comprise the NCS, DIN and OSA-UCS colour atlases.

When analyzing medical utilization or other health care-related measurements across provider panels, case mix adjustment is required because "illness burden" is often unevenly distributed across these patient populations. This article develops the rationale for case mix adjustment and walks readers through the case mix adjustment process using the Johns Hopkins Ambulatory Care Group (ACG) Case-Mix System as a model. The ACG system is a population-oriented patient classification tool based on diagnoses assigned by providers and found in payors' data systems. The system categorizes patients according to illness burden. It does not categorize visits, encounters, or episodes. ACGs adjust for case mix differences in the analysis of ambulatory, laboratory, pharmacy, and total health care service delivery.

Since the original observation and description of the various forms of Bleomycin (BLM), numerous articles have appeared dealing with the activity on mammalian cells and its possible clinical use. The present review on this very important compound, although not very comprehensive, deals with the important characteristics; such as the action of DNA and cells, and its chromosome breaking effects. The manner in which the minute detail of the action of BLM on cells has helped to implement in vivo chemotherapeutic regimes, is also discussed.

In this investigation dielectric constant and loss tangent values of coal samples were computed from measurements made at microwave frequencies (8.2–12.4 GHz). Two different waveguide methods were used in the measurements. One technique utilized a finite sample and two reactive terminations, and the other required the use of an infinite sample simulated in the laboratory by a very long specimen. For each of the two Pittsburgh seam coal samples, dielectric constant and loss tangent variations were also measured as a function of moisture. Typical moisture contents of 10% and 15% were examined. Electromagnetic propagation through a single layer of coal seam was then investigated analytically as a function of coal depth.

A theoretical model which includes the effects of contaminants is developed for the high flow electric discharge CO2-N2-He laser. The model couples the excitation and relaxation processes, CO2 dissociation, and negative ion formation with the flow processes. An analysis of the effects of CO, O2, NO, and N2O impurities on the average small signal gain is presented. CO decreases the gain by collisional depopulation of the upper laser level, and O2, NO, and N2O reduce the gain by decreasing the electron density by forming stable negative ions. In particular, N2O exhibits a strong quenching effect because of its large dissociation cross section for the formation of O(-).