Diet of sardine Sardinops sagax in the southern Benguela upwelling ecosystem

The diet of sardine Sardinops sagax in the southern Benguela was investigated by microscopic examination of stomach contents. The relative dietary importance of prey size and prey type was assessed by calculating the carbon content of prey items. Sardine is an omnivorous clupeoid, ingesting both phytoplankton and zooplankton, with the relative importance of these two food types varying both spatially and temporally. Stomach contents were numerically dominated by small prey items, principally dinoflagellates, followed by crustacean eggs, cyclopoid copepods, calanoid copepods and diatoms. Virtually all prey items ingested by sardine wer

Gastric evacuation, feeding periodicity and daily ration of Sardine sardinops sagax in the southern Benguela upwelling ecosystem

Laboratory and field experiments were conducted to determine gastric evacuation rates of sardine Sardinops sagax, and stomach content analyses were undertaken to assess feeding periodicity and estimate the daily ration of this species in the southern Benguela. Gastric evacuation followed an exponential pattern and was influenced by food type; phytoplankton was evacuated at a much faster rate than zooplankton. Estimated gastric evacuation rates ranged between 0.05 and 0.29.h-1, with mean values of 0.09 and 0.27.h-1 for fish fed zooplankton and phytoplankton respectively. Despite this large range, no significant relationships were found between gastric evacuation rate and fish size, temperature, food particle size or meal size. Feeding periodicity was size-dependent; small fish had a peak in feeding activity at or around sunset, whereas larger fish appeared to feed continuously. This suggests that fish of different size exhibit different foraging behaviours, possibly reflecting differences in their diets. Estimates of daily ration ranged from 0.99 to 2.52% wet body mass.day-1 for fish consuming zooplankton and from 2.97 to 7.58% wet body mass.day-1 for fish consuming phytoplankton. Small fish consumed a bigger daily ration than large fish

What can polysemy tell us about theories of explanation?

Philosophical accounts of scientific explanation are broadly divided into ontic and epistemic views. This paper explores the idea that the lexical ambiguity of the verb to explain and its nominalisation supports an ontic conception of explanation. I analyse one argument which challenges this strategy by criticising the claim that explanatory talk is lexically ambiguous, 375–394, 2012). I propose that the linguistic mechanism of transfer of meaning, 109–132, 1995) provides a better account of the lexical alternations that figure in the systematic polysemy of explanatory talk, and evaluate the implications of this proposal for the debate between ontic and epistemic conceptions of scientific explanation

A novel method for high-throughput detection and quantification of neutrophil extracellular traps reveals ROS-independent NET release with immune complexes

AbstractA newly-described first-line immune defence mechanism of neutrophils is the release of neutrophil extracellular traps (NETs). Immune complexes (ICxs) induce low level NET release. As such, the in vitro quantification of NETs is challenging with current methodologies. In order to investigate the role of NET release in ICx-mediated autoimmune diseases, we developed a highly sensitive and automated method for quantification of NETs. After labelling human neutrophils with PKH26 and extracellular DNA with Sytox green, cells are fixed and automatically imaged with 3-dimensional confocal laser scanning microscopy (3D-CLSM). NET release is then quantified with digital image analysis whereby the NET amount (Sytox green area) is corrected for the number of imaged neutrophils (PKH26 area). A high sensitivity of the assay is achieved by a) significantly augmenting the area of the well imaged (11%) as compared to conventional assays (0.5%) and b) using a 3D imaging technique for optimal capture of NETs, which are topologically superimposed on neutrophils. In this assay, we confirmed low levels of NET release upon human ICx stimulation which were positive for citrullinated histones and neutrophil elastase. In contrast to PMA-induced NET release, ICx-induced NET release was unchanged when co-incubated with diphenyleneiodonium (DPI). We were able to quantify NET release upon stimulation with serum from RA and SLE patients, which was not observed with normal human serum. To our knowledge, this is the first semi-automated assay capable of sensitive detection and quantification of NET release at a low threshold by using 3D CLSM. The assay is applicable in a high-throughput manner and allows the in vitro analysis of NET release in ICx-mediated autoimmune diseases

A comparison of condition factor and gona dosomatic index of sardine Sardinops sagax stocks in the northern and southern Benguela upwelling ecosystems, 1984–1999

Time-series of condition factor (CF) and gonadosomatic index (GSI) were generated using general linear models (GLM) for sardine Sardinops sagax stocks in the northern and southern Benguela ecosystems over the period 1984–1999. During this period the biomass of sardine in the northern Benguela remained at relatively low levels of African Journal of Marine Science 2001, 23: 123–13

Best Practices and Innovations for Managing Codeine Misuse and Dependence.

PURPOSE: Promoting and ensuring safe use of codeine containing medicines remains a public health issue given the rise in reporting of misuse and dependence particularly in countries where available over-the-counter (OTC). The aim of this unique study was to identify best practices in management of opioid abuse and dependence, particularly codeine, and innovations to meet challenges surrounding safe and compliant use, patient awareness-raising, reducing health harms and enhancing successful treatment of dependence. METHODS: A mixed methods approach using three data points was used that included : (1) analysis of data from existing scoping reviews to identify potential areas for innovation (2) interviews with key national stakeholders from public health, pharmaceutical, regulatory, primary care and addiction practice in three distinct regulatory regimes (Ireland, United Kingdom and South Africa); and (3) a circular email request for information on potential innovations to members of the European Medicine's Agency European Network of Centres for Pharmacoepidemiology and Pharmacovigilance (ENCEPP). Data from these three sources were analysed to identify best practices and opportunities for innovation. RESULTS: Best practices and potential innovations were identified under the nine headings: (1) manufacture; (2) product information and public education; (3) responsible prescribing; (4) monitoring and surveillance; (5) dispensing, screening and brief interventions in community pharmacies; (6) safety in the workplace and on the road; (7) internet supply of codeine and online support; (8) treatment of codeine dependence; and (9) learning resources and training for health professionals. CONCLUSIONS: Challenges ensuring availability of codeine containing medicines for legitimate therapeutic use, while minimising misuse, dependence and related health harms warrant consideration of new innovations. Most promising innovative potential lies across the products' retail lifecycle from manufacture to prescriber and community pharmacy practitioner.This article is open to POST-PUBLICATION REVIEW. Registered readers (see "For Readers") may comment by clicking on ABSTRACT on the issue's contents page

Next-to-leading power threshold effects for inclusive and exclusive processes with final state jets

It is well known that cross-sections in perturbative QCD receive large corrections from soft and collinear radiation, which can be resummed to all orders in the coupling. Whether or not the universal properties of this radiation can be extended to next-to-leading power (NLP) in the threshold expansion has been the subject of much recent study. In particular, universal forms for next-to-leading order (NLO) cross-sections have been obtained for general colour-singlet production processes by considering only the emission of gluons. In this paper, we extend such formulae to processes containing final state jets, and show that the dominant NLP terms at NLO can be obtained using a similar prescription to the colour-singlet case. We furthermore consider the emission of soft quarks, which also leads to a class of universal NLP contributions at NLO. We illustrate our results using three different processes at NLO: deep-inelastic scattering, hadroproduction via electron-positron annihilation and prompt photon production

A complete characterization of plateaued Boolean functions in terms of their Cayley graphs

In this paper we find a complete characterization of plateaued Boolean functions in terms of the associated Cayley graphs. Precisely, we show that a Boolean function $f$ is $s$-plateaued (of weight $=2^{(n+s-2)/2}$) if and only if the associated Cayley graph is a complete bipartite graph between the support of $f$ and its complement (hence the graph is strongly regular of parameters $e=0,d=2^{(n+s-2)/2}$). Moreover, a Boolean function $f$ is $s$-plateaued (of weight $\neq 2^{(n+s-2)/2}$) if and only if the associated Cayley graph is strongly $3$-walk-regular (and also strongly $\ell$-walk-regular, for all odd $\ell\geq 3$) with some explicitly given parameters.Comment: 7 pages, 1 figure, Proceedings of Africacrypt 201