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Background The interleukin 36 (IL-36) family consists of three agonists (IL-36α, IL-36β, IL-36γ), that activate the NF-κB pathway and lead to the production of pro-inflammatory cytokines and the natural antagonist (IL-36RA), which inhibits IL-36 signaling. While it is known that IL-36 signaling is important in the skin, it has been only recently reported that IL-36 might play an important role in maintaining gut homeostasis and in the development of fibrosis (Scheibe et al., 2019). Here, we aim to understand how IL-36RA mutations contribute to development and maintenance of intestinal inflammation in Crohn’s disease. Methods By whole-exome sequencing (WES) and subsequently targeted Sanger sequencing we identified a Crohn’s disease (CD) patient with a heterozygous missense mutation in IL-36RA (p.Ser113Leu). To understand how the mutation affects immune cells composition and function, we characterized peripheral blood mononuclear cells (PBMCs) of the patient by mass cytometry and measured cytokine levels in the serum by ELISA. In an available WES dataset of 177 CD patients, 47 ulcerative colitis (UC) patients and 34 healthy donors (HD), we searched for additional patients with IL-36RA mutations. Finally, we overexpressed the identified IL-36RA mutations in HEK cells and produced mutated recombinant proteins to study the effect of the mutations on protein expression and function. Results Our IL-36RA mutation-carrying patient presented with a severe course of Crohn’s disease and consecutive of fibrosis, which was resistant to all commonly used treatment options. In the patient, we detected increased levels of IL-36RA, IL-18 and IL-23 in the serum and an increased frequency of TH17 cells in the blood. These findings could hint towards an over-activation of the IL-36 signaling pathway in the IL-36RA mutated patient. In the available WES data, we identified two more CD patients with IL-36RA mutations (p.Leu133Ile, p.Pro76Leu), indicating that IL-36RA mutations are enriched in CD patients. By overexpressing the three identified mutations in HEK cells, we could demonstrate that two mutations (p.Ser113Leu and p.Pro76Leu) lead to a reduced protein expression. Also, our current data shows that the p.Ser113Leu mutant has a reduced capacity to antagonize IL-36 stimulation. However, further testing is required for the two other IL-36RA mutants. Conclusion Our data suggests that IL-36RA mutations are enriched in Crohn’s disease patients and should be considered as a possible cause for therapy-refractory and fibrotic Crohn’s disease.

Fasting ketoacidosis is especially an underdiagnosed problem in patients with neuro-muscular disease with severely depleted muscular mass. During periods of prolonged fasting, low levels of insulin and high levels of glucagon induce lipolysis in the peripheral fat tissue. This will result in elevated free fatty acids levels in de blood and increased ketogenesis in the liver. These ketones pass into the blood, leading to a ketoacidosis. Patients with low muscular mass are more susceptible to develop ketoacidosis due to lower energy reserves and reduced glycogen stores on the one hand, and a reduced uptake of ketones by their low muscular mass on the other hand. During periods of increased metabolism and in the absence of adequate caloric intake, this can easily lead to severe ketoacidosis. An adequate oral caloric intake is essential in the prevention and treatment of fasting ketoacidosis.

A measurement of the double-polarization observable E for the reaction $$\gamma p\rightarrow \pi ^0 p$$ γ p → π 0 p is reported. The data were taken with the CBELSA/TAPS experiment at the ELSA facility in Bonn using the Bonn frozen-spin butanol (C$$_4$$ 4 H$$_9$$ 9 OH) target, which provided longitudinally-polarized protons. Circularly-polarized photons were produced via bremsstrahlung of longitudinally-polarized electrons. The data cover the photon energy range from $$E_\gamma =600$$ E γ = 600 to 2310 MeV and nearly the complete angular range. The results are compared to and have been included in recent partial wave analyses.

Context: Neuromodulation is an expanding field of study for headache treatment to reduce pain by targeting structures within the nervous system that are commonly involved in headache pathophysiology, such as the vagus nerve (VNS), occipital nerves, or sphenopalatine ganglion (SPG) for stimulation. Pharmaceutical medical therapies for abortive and prophylactic treatment, such as triptans, NSAIDs, beta-blockers, TCAs, and antiepileptics, are effective for some individuals, but the role that technology plays in investigating other therapeutic modalities is essential. Peripheral neuromodulation has gained popularity and FDA approval for use in treating certain headaches and migraine headache conditions, particularly in those who are refractory to treatment. Early trials found FDA approved neurostimulatory implant devices, including Cephaly and SpringTMS, improved patient-oriented outcomes with reductions in headaches per month (frequency) and severity. Evidence Acquisition: This was a narrative review. The sources for this review are as follows: Searching on PubMed, Google Scholar, Medline, and ScienceDirect from 1990 - 2019 using keywords: Peripheral Neuromodulation, Headache, vagus nerve, occipital nerves, sphenopalatine ganglion. Results: The first noninvasive neurostimulator device approved for migraine treatment was the Cefaly device, an external trigeminal nerve stimulation device (e-TNS) that transcutaneously excites the supratrochlear and supraorbital branches of the ophthalmic nerve. The second noninvasive neurostimulation device receiving FDA approval was the single-pulse transcranial magnetic stimulator, SpringTMS, positioned at the occiput to treat migraine with aura. GammaCore is a handheld transcutaneous vagal nerve stimulator applied directly to the neck at home by the patient for treatment of cluster headache (CH) and migraine. Several other devices are in development for the treatment of headaches and target headache evolution at different levels and inputs. The Scion device is a caloric vestibular stimulator (CVS) which interfaces with the user through a set of small cones resting in the ear canal on either side and held in place by modified over-ear headphones. The pulsante SPG Microstimulator is a patient-controlled device implanted in the patient’s upper jaw via an hour-long oral procedure to target the sphenopalatine ganglion. The occipital nerve stimulator (ONS) is an invasive neuromodulation device for headache treatment that consists of an implanted pulse generator on the chest wall connected to a subcutaneous lead with 4 - 8 electrodes that is tunneled the occiput. Conclusions: The aim of this review is to provide a comprehensive overview of the efficacy, preliminary outcomes, and limitations of neurostimulatory implants available for use in the US and those pending further development.

Data on the beam asymmetry Σ in the photoproduction of η mesons off protons are reported for tagged photon energies from 1130 to 1790 MeV (mass range from W=1748 MeV to W=2045 MeV). The data cover the full solid angle that allows for a precise moment analysis. For the first time, a strong cusp effect in a polarization observable has been observed that is an effect of a branch-point singularity at the pη^{'} threshold [E_{γ}=1447 MeV (W=1896 MeV)]. The latest BnGa partial wave analysis includes the new beam asymmetry data and yields a strong indication for the N(1895)1/2^{-} nucleon resonance, demonstrating the importance of including all singularities for a correct determination of partial waves and resonance parameters.

Data on the beam asymmetry Σ in the photoproduction of η mesons off protons are reported for tagged photon energies from 1130 to 1790 MeV (mass range from W=1748 MeV to W=2045 MeV). The data cover the full solid angle that allows for a precise moment analysis. For the first time, a strong cusp effect in a polarization observable has been observed that is an effect of a branch-point singularity at the pη^{'} threshold [E_{γ}=1447 MeV (W=1896 MeV)]. The latest BnGa partial wave analysis includes the new beam asymmetry data and yields a strong indication for the N(1895)1/2^{-} nucleon resonance, demonstrating the importance of including all singularities for a correct determination of partial waves and resonance parameters.

A measurement of the double-polarization observable E for the reaction \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\gamma p\rightarrow \pi ^0 p$$\end{document}γp→π0p is reported. The data were taken with the CBELSA/TAPS experiment at the ELSA facility in Bonn using the Bonn frozen-spin butanol (C\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$_4$$\end{document}4H\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$_9$$\end{document}9OH) target, which provided longitudinally-polarized protons. Circularly-polarized photons were produced via bremsstrahlung of longitudinally-polarized electrons. The data cover the photon energy range from \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$E_\gamma =600$$\end{document}Eγ=600 to 2310 MeV and nearly the complete angular range. The results are compared to and have been included in recent partial wave analyses.

The polarization observables T , E , P , H , and G in photoproduction of η mesons off protons are measured for photon energies from threshold to W = 2400 MeV (T), 2280 MeV (E), 1620 MeV ( P , H ), or 1820 MeV (G), covering nearly the full solid angle. The data are compared to predictions from the SAID, MAID, JuBo, and BnGa partial-wave analyses. A refit within the BnGa approach including further data yields precise branching ratios for the Nη decay of nucleon resonances. A Nη-branching ratio of 0.33 ± 0.04 for N ( 1650 ) 1 / 2 − is found, which reduces the large and controversially discussed Nη-branching ratio difference of the two lowest mass J P = 1 / 2 − -resonances significantly.

The production of $\eta^{\prime}$ mesons in coincidence with forward-going protons has been studied in photon-induced reactions on 12C and on a liquid hydrogen (LH2) target for incoming photon energies of 1.3-2.6 GeV at the electron accelerator ELSA. The $\eta^{\prime}$ mesons have been identified via the $\eta^{\prime} \rightarrow \pi^{0} \pi^{0}\eta \rightarrow 6 \gamma$ decay registered with the CBELSA/TAPS detector system. Coincident protons have been identified in the MiniTAPS BaF2 array at polar angles of $2^{\circ} \le \theta_{p} \le 11^{\circ}$ . Under these kinematic constraints the $\eta^{\prime}$ mesons are produced with relatively low kinetic energy ( $\approx 150$ MeV) since the coincident protons take over most of the momentum of the incident-photon beam. For the C-target this allows the determination of the real part of the $\eta^{\prime}$ -carbon potential at low meson momenta by comparing with collision model calculations of the $\eta^{\prime}$ kinetic energy distribution and excitation function. Fitting the latter data for $\eta^{\prime}$ mesons going backwards in the center-of-mass system yields a potential depth of $V = -(44 \pm 16(stat) \pm 15(syst))$ MeV, consistent with earlier determinations of the potential depth in inclusive measurements for average $\eta^{\prime}$ momenta of $\approx 1.1$ GeV/c. Within the experimental uncertainties, there is no indication of a momentum dependence of the $\eta^{\prime}$ -carbon potential. The LH2 data, taken as a reference to check the data analysis and the model calculations, provide differential and integral cross sections in good agreement with previous results for $\eta^{\prime}$ photoproduction off the free proton.

The first measurements of the beam-target-helicity-asymmetries $E$ and $G$ in the photoproduction of $\omega$-mesons off protons at the CBELSA/TAPS experiment are reported. $E$ ($G$) was measured using circularly (linearly) polarised photons and a longitudinally polarised target. $E$ was measured over the photon energy range from close to threshold ($E_\gamma = 1108$~MeV) to $E_\gamma = 2300$~MeV and $G$ at a single energy interval of $1108 < E_\gamma, Comment: 6 pages, 6 figures

Data on the polarization observables T, P, and H for the reaction gamma p -> p pi(0) are reported. Compared to earlier data from other experiments, our data are more precise and extend the covered range in energy and angle substantially. The results were extracted from azimuthal asymmetries measured using a transversely polarized target and linearly polarized photons. The data were taken at the Bonn electron stretcher accelerator ELSA with the CBELSA/TAPS detector. Within the Bonn-Gatchina partial wave analysis, the new polarization data lead to a significant narrowing of the error band for the multipoles for neutral-pion photoproduction. (C) 2015 The Authors. Published by Elsevier B.V.

Aims: To investigate cellular changes in the spinal trigeminal nucleus (STN) and trigeminal ganglion (TG) associated with trigeminal nociception mediated by inflammation in the temporomandibular joint (TMJ). Methods: Male Sprague- Dawley rats (n = 86) were utilized to investigate cellular and behavioral responses to prolonged TMJ inflammation caused by bilateral injection of Complete Freund's Adjuvant (CFA) in the TMJ capsules. To investigate the cellular effects of protein kinase A (PKA) in the STN, rats were injected intrathecally with the selective PKA inhibitor KT5720 prior to injection of CFA into both TMJ capsules. Levels of calcitonin gene-related peptide (CGRP), active PKA, and ionized calciumbinding adapter molecule 1 (Iba1) in the STN and expression of phosphorylated extracellular regulated kinases (p-ERK) in the TG were determined with immunohistochemistry (n ≥ 3 experiments per test condition). Nocifensive head withdrawal responses to mechanical stimulation of the cutaneous tissue over the TMJ were monitored following CFA injection in the absence or presence of KT5720 (n = 7). Statistical analysis was performed using parametric analysis of variance (ANOVA) tests. Results: Intrathecal injection of KT5720 significantly inhibited the stimulatory effect of CFA on levels of CGRP, PKA, and Iba1 in the STN. In addition, administration of KT5720 decreased the average number of CFA-induced nocifensive withdrawal responses to mechanical stimulation and the CFA-mediated increase in p-ERK expression in the ganglion. Conclusion: These findings provide evidence that elevated PKA activity in the STN promotes cellular events temporally associated with trigeminal nociception caused by prolonged TMJ inflammation.

Although a considerable amount of work has been done on open estuaries in southern Africa very few studies have been on estuaries that are normally closed. The Bot River vlei is an estuary of this type, and the information presented here is the result of initial surveys carried out in 1980. The vlei, situated on the south-west coast of South Africa, has recently been opened to the sea. The salinity at the time of survey ranged from 7–12°/oo, although this is subject to seasonal fluctuations and artificial opening of the estuary. The major primary producers are the reeds Phragmites and Scirpus which may reach a biomass of 1,794 and 0,961 kg dry mass m-2 and the aquatic macrophytes Potamogeton (0,071 kg m-2), Ruppia (0,371 kg m-2), Chara (0,071 kg m-2) and Cladophora (0,140 kg m -2) growing down to water depths of 2,9 m. The invertebrate fauna is poor both in terms of biomass and diversity, but large numbers of birds, particularly herbivorous coots, and fish are found. The Bot River estuary appears to be in...

Photoproduction of $\eta$ mesons from neutrons} \abstract{Results from measurements of the photoproduction of $\eta$ mesons from quasifree protons and neutrons are summarized. The experiments were performed with the CBELSA/TAPS detector at the electron accelerator ELSA in Bonn using the $\eta\to3\pi^{0}\to6\gamma$ decay. A liquid deuterium target was used for the measurement of total cross sections and angular distributions. The results confirm earlier measurements from Bonn and the MAMI facility in Mainz about the existence of a narrow structure in the excitation function of $\gamma n\rightarrow n\eta$. The current angular distributions show a forward-backward asymmetry, which was previously not seen, but was predicted by model calculations including an additional narrow $P_{11}$ state. Furthermore, data obtained with a longitudinally polarized, deuterated butanol target and a circularly polarized photon beam were analyzed to determine the double polarization observable $E$. Both data sets together were also used to extract the helicity dependent cross sections $\sigma_{1/2}$ and $\sigma_{3/2}$. The narrow structure in the excitation function of $\gamma n\rightarrow n\eta$ appears associated with the helicity-1/2 component of the reaction.

The photoproduction of $\omega$ and $\eta^\prime$ mesons off carbon and niobium nuclei has been measured as a function of the meson momentum for incident photon energies of 1.2-2.9 GeV at the electron accelerator ELSA. The mesons have been identified via the $\omega \rightarrow \pi^0 \gamma \rightarrow 3 \gamma$ and $\eta^\prime\rightarrow \pi^0 \pi^0\eta \rightarrow 6 \gamma$ decays, respectively, registered with the CBELSA/TAPS detector system. From the measured meson momentum distributions the momentum dependence of the transparency ratio has been determined for both mesons. Within a Glauber analysis the in-medium $\omega$ and $\eta^\prime$ widths and the corresponding absorption cross sections have been deduced as a function of the meson momentum. The results are compared to recent theoretical predictions for the in-medium $\omega$ width and $\eta^\prime$-N absorption cross sections. The energy dependence of the imaginary part of the $\omega$- and $\eta^\prime$-nucleus optical potential has been extracted. The finer binning of the present data compared to the existing data allows a more reliable extrapolation towards the production threshold. The modulus of the imaginary part of the $\eta^\prime$ nucleus potential is found to be about three times smaller than recently determined values of the real part of the $\eta^\prime$-nucleus potential, which makes the $\eta^\prime$ meson a suitable candidate for the search for meson-nucleus bound states. For the $\omega$ meson, the modulus of the imaginary part near threshold is comparable to the modulus of the real part of the potential. As a consequence, only broad structures can be expected which makes the observation of $\omega$ mesic states very difficult experimentally., Comment: 10 pages, 8 figures

The new BGO-OD experiment at the electron accelerator ELSA, of the University of Bonn, is designed to study the reaction dynamics of nucleon excitations in meson photoproduction. It consists of a central BGO calorimeter with a magnetic spectrometer in forward direction. The physics programme includes the measurement of polarisation observables using linearly and circularly polarised photon beams. Linear polarisation is obtained by coherent bremsstrahlung off a diamond crystal, and circular polarisation is obtained via bremsstrahlung from longitudinally polarised electrons. The degree of linear polarisation is determined from the bremsstrahlung spectrum itself. To determine the polarisation of the circularly polarised photon beam, the polarisation of the electron beam is measured by a Moller polarimeter. As a preliminary consistency check, the (linear) polarisation observable, Σ, was compared to world data for π^0 and η photoproduction. To determine the degree of circular polarisation, a Moller polarimeter was setup and first measurements of the electron beam polarisation performed.

The excitation function and momentum distribution of {\eta}' mesons have been measured in photoproduction off 93^Nb in the energy range of 1.2-2.9 GeV. The experiment has been performed with the combined Crystal Barrel and MiniTAPS detector system, using tagged photon beams from the ELSA electron accelerator. Information on the sign and magnitude of the real part of the {\eta}'-Nb potential has been extracted from a comparison of the data with model calculations. An attractive potential of -(41 \pm 10(stat) \pm 15(syst)) MeV depth at normal nuclear matter density is deduced within model uncertainties. This value is consistent with the potential depth of -(37 \pm 10(stat) \pm 10(syst)) MeV obtained in an earlier measurement for a light nucleus (carbon). This relatively shallow {\eta}'-nucleus potential will make the search for {\eta}'-nucleus bound states more difficult., Comment: 9 pages, 6 figures

BGO-OD is a new meson photoproduction experiment at the ELSA facility of Bonn University. It aims at the investigation of non strange and strange baryon excitations, and is especially designed to be able to detect weekly bound meson-baryon type structures. The setup for the BGO-OD experiment is presented, the characteristics of the photon beam and the detector performances are shown and the initial experimental program is discussed.

This paper reports on a measurement of the double-polarization observable G in $\pi^0$ photoproduction off the proton using the CBELSA/TAPS experiment at the ELSA accelerator in Bonn. The observable G is determined from reactions of linearly-polarized photons with longitudinally-polarized protons. The polarized photons are produced by bremsstrahlung off a properly oriented diamond radiator. A frozen spin butanol target provides the polarized protons. The data cover the photon energy range from 617 to 1325 MeV and a wide angular range. The experimental results for G are compared to predictions by the Bonn-Gatchina (BnGa), J\"ulich-Bonn (J\"uBo), MAID and SAID partial wave analyses. Implications of the new data for the pion photoproduction multipoles are discussed.

BGO-OD is a newly commissioned experiment to investigate the internal structure of the nucleon, using an energy tagged bremsstrahlung photon beam at the ELSA electron facility. The setup consists of a highly segmented BGO calorimeter surrounding the target, with a particle tracking magnetic spectrometer at forward angles. BGO-OD is ideal for investigating meson photoproduction. The extensive physics programme for open strangeness photoproduction is introduced, and preliminary analysis presented., 6 pages, 4 figures. Proceedings for the 10th International Workshop on the Physics of Excited Nucleons (NSTAR2015)

Biomass in combination with carbon capture and storage (CCS) technologies is one of few options that makes an actual reduction of global CO2 concentration in the atmosphere possible and is likely to be required to meet low atmospheric concentration of CO2. This study shows the global potential for combining biomass with CCS technologies (bio-CCS) up to 2030 and 2050. The assessment includes six bio-CCS routes for the production of power and biofuels in combination with CCS. For these routes we have analysed the technical and economic potential. The results show the global technical potential for bio-CCS technologies is large and, if deployed, can result in negative greenhouse gas emissions (GHG) up to 10.4 Gt CO2 eq. on an annual basis in 2050. This is a large reduction potential compared to the global energy-related CO2 emissions which grew to 30.6 Gt CO2 in 2010. The economic potential reaches up to 3.5 Gt of negative GHG emissions when assuming a CO2 price of 50 €/tonne. Next to quantitative estimates of these potentials in the form of global cost supply curves, we present recommendations to overcome possible barriers and enhance drivers to stimulate the deployment of bio-CCS technologies.

A manipulative mesocosm experiment was done in a saline coastal lake in Australia to compare the top-down and bottom-up influences of jellyfish on primary production and planktonic assemblages. We hypothesized that non-zooxanthellate jellyfish (Catostylus mosaicus) would exert both ‘top-down’ (grazing) and ‘bottom-up’ (nutrient excretion) effects, whereas zooxanthellate jellyfish (Phyllorhiza punctata) would only exert top-down influences, as their dissolved excretory products are internally recycled to their zooxanthellae rather than released into the water column. Experimental treatments consisted of triplicate mesocosms that contained two C. mosaicus, two P. punctata, a combination of C. mosaicus and P. punctata, no jellyfish, and an open-water control (sampling outside mesocosms). Both species of jellyfish preyed heavily on mesozooplankton, initiating a topdown trophic cascade that resulted in increased production of the heterotrophic dinoflagellate Protoperidinium sp. However, no increase in primary production or phytoplankton biomass was observed in the treatments containing P. punctata, indicating that top-down processes did not extend to primary producers. Bottom-up excretion of nutrients, however, caused phytoplankton biomass to more than double in the C. mosaicus treatment compared to all other treatments. Increased primary production was due largely to a 10-fold increase in the diatom Chaetoceros sp. and was predominantly driven by C. mosaicus excreting phosphate (PO 3{ 4 ), which was the limiting nutrient in the lake. Blooms of both zooxanthellate and non-zooxanthellate jellyfish will deplete mesozooplankton and alter the composition of microzooplankton assemblages via top-down processes. Excretion of nutrients by blooms of non-zooxanthellate jellyfish, however, can also greatly increase phytoplankton production and could favor algal blooms.

A river classification framework is needed to make good management and planning decisions about river health and biodiversity. We developed a multi-attribute ecological river typology to address this need in the Australian State of New South Wales (801,428 km2). Multivariate patterns in data collected from 322 reference sites were used to define river types for each attribute: abiotic features (10 types), fish assemblages (6 types) and macroinvertebrate assemblages from river edges (8 types) and riffle zones (5 types). We used classification tree analysis to define broad regions for each attribute and then to construct identification keys for river types within each region using slope, elevation, maximum distance from source, latitude and mean annual rainfall. These keys allow the mapping of the likely spatial extent of river types and the assignment of a multi-attribute river-type identity to a river reach anywhere in the State. We used the average dissimilarity distances among the river types and the rates of misclassification of reference sites to assess the reliability of the assignments for different attributes in different regions. This approach to river classification can be applied anywhere in the world, resulting in simple to highly complex typologies depending on data availability. In data-poor areas it may result in a single attribute typology based on remotely derived variables and a coarsely defined reference condition. In data-rich areas the typology may have a large number of attributes using very large datasets with high resolution.

The short-term effects of pulses of nutrients and jellyfish Catostylus mosaicus on planktonic assemblages were investigated in field-based experiments using 3 m3 mesocosms. Experiments ran for 5 d and were repeated in autumn and spring at Lake Illawarra, a coastal lagoon in New South Wales, Australia. Experiments consisted of 2 orthogonal treatments, addition/non-addition of nutrients and presence/absence of jellyfish, and were designed to determine how bottom-up (i.e. addition of nutrients) and top-down (i.e. predation by jellyfish) processes influence planktonic assemblages, both independently and in combination. During both experiments, nutrients stimulated primary production and caused changes in phytoplankton assemblages. Nutrients also stimulated production of large tintinnids, suggesting that bottom-up processes may influence 2 trophic levels. Mesozooplankton were consistently depleted in mesocosms containing jellyfish. Jellyfish also caused changes in microzooplankton assemblages, indicating that top-down processes also cascade to at least 2 trophic levels. In mesocosms to which both nutrients and jellyfish were added during spring, concentrations of the red-tide forming, heterotrophic dinoflagellate Noctiluca scintillans were 20 times greater than in mesocosms to which nutrients were added alone. We hypothesize that addition of nutrients stimulated production of centric diatoms, the main prey of N. scintillans, but that a bloom of N. scintillans only formed when jellyfish were also present because jellyfish grazed on populations of herbivorous mesozooplankton (particularly the calanoid copepod Gladioferens), which generally out-competed N. scintillans for diatom prey. These data provide the first empirical evidence linking jellyfish to the formation of red tides.

Australian science has made rapid advances in the last decade in understanding eutrophication processes in inland waters and estuaries. The freshwater research on which these advances are based was triggered by well-publicised blooms of cyanobacteria during the 1980s and early 1990s, particularly a 1000 km long bloom on the Darling River. In estuaries the study which greatly enhanced our understanding but simultaneously served to stimulate further research into estuarine eutrophication, the Port Phillip Bay Study, was initially designed to address perceived problems of toxicants in the Bay but provided profound insights into drivers for, and ecosystem responses to, eutrophication. Subsequent estuarine research has largely been stimulated by management questions arising from Australia’s increasing coastal development for residential purposes. The research has shown that some of the beliefs extant at the time of the blooms were incorrect. For example, it is now clear that stratification and light penetration, not nutrient availability, are the triggers for blooms in the impounded rivers of southeastern Australia, although nutrient exhaustion limits the biomass of blooms. Again, nitrogen seems to play as important a role as phosphorus does in controlling the biomass of these freshwater blooms. The research has also shown that aspects of eutrophication, such as nutrient transport, are dominated by different processes in different parts of Australia. Many of the biophysical processes involved in eutrophication have now been quantified sufficiently for models to be developed of such processes as sediment-nutrient release, stratification, turbidity and algal growth in both freshwater and estuarine systems. In some cases the models are reliable enough for the knowledge gained in particular waterbodies to be applied elsewhere. Thus, there is now a firm scientific foundation for managers to rely upon when managing algal blooms. Whilst these findings have already been presented to managers and communities throughout Australia, there is still a considerable way to go before they are absorbed into their modus operandi.

The rhizostome jellyfishes, Catostylus mosaicus and Phyllorhiza punctata abound in estuaries in New South Wales, Australia. P. punctata contains symbiotic zooxanthellae but C. mosaicus contains few or no zooxanthellae. Our experiment measured the rates at which NH 3 , PO 4 and NO x were taken up or excreted by each species and in two controls: a “water only” control and a “mucus” control. Rates of uptake or excretion were measured as changes in the nutrient concentration of the water in the containers housing the animals over periods of 6 h. Experiments were repeated twice during the day and twice at night, under both ambient and enriched nutrient conditions. Under ambient nutrient conditions, the flux of NH 3 in the P. punctata treatment did not differ from the controls but under enriched conditions P. punctata excreted NH 3 during the night (49 μg kg −1 WW (wet weight) h −1 ) and took up NH 3 during the day (123 μg kg −1 WW h −1 ). In contrast, C. mosaicus excreted NH 3 at a rate of 1555 μg kg −1 WW h −1 during the day and 1004 μg kg −1 WW h −1 during the night under both enriched and ambient nutrient conditions. P. punctata neither took up nor excreted PO 4 but C. mosaicus excreted PO 4 at a faster rate during the day than night (173 μg kg −1 WW h −1 cf. 104 μg kg −1 WW h −1 ). Both C. mosaicus and P. punctata excreted NO x and, although the rate of excretion for P. punctata varied between the two experiments conducted during the day, the rate of excretion was consistently greater than for C. mosaicus (52 and 80 μg kg −1 WW h −1 cf. 26 μg kg −1 WW h −1) . Tubs containing P. punctata had a much greater concentration of dissolved oxygen at the end of the experiments conducted during the day (152% saturation) than night (60% saturation) but tubs containing C. mosaicus had a greater dissolved oxygen concentration during the night (47% saturation) than day (39%). Overall, C. mosaicus appears to recycle more inorganic nutrients to estuaries than P. punctata . Calculations of the importance of inorganic nitrogen excreted by this species during times of peak biomass in Lake Illawarra suggest that it can meet about 8% of the phytoplankton primary production requirements of N and that its inorganic N excretion rate is about 11% of measured inorganic ammonia fluxes from sediments in that system. Since the biomass of C. mosaicus often exceeds several thousand tonnes, the contribution of inorganic nutrients by this species is substantial.

The results are reported of an experimental study of the gas holdup, EG, large bubble diameter, d Lb , and large bubble rise velocity, V Lb , in a 0.1 m wide, 0.02 m deep and 0.95 m high rectangular slurry bubble column operated at ambient temperature and pressure conditions. The superficial gas velocity U was varied in the range of 0-0.2 m/s, spanning both the homogeneous and heterogeneous flow regimes. Air was used as the gas phase. The liquid phase used was C 9 -C 11 Paraffin oil containing varying volume fractions (e s = 0, 0.05. 0.10, 0.15, 0.20 and 0.25) of porous catalyst (alumina catalyst support, 10% 0.05 and U > 0.1 m/s. The measured large bubble rise velocity V Lb agrees with the predictions of a modified Davis-Taylor relationship.

We report the results of an experimental study of the gas holdup, e G , and volumetric mass transfer coefficient, k L a, in a bubble column slurry reactor of 0.1 m diameter operated at ambient temperature and pressure conditions. The superficial gas velocity U was varied in the range 0-0.4m/s, spanning both the homogeneous and churn-turbulent flow regimes. Air was used as the gas phase. The liquid phase used was C 9 -C 11 Paraffin oil containing varying volume fractions (e S = 0, 0.05, 0.10, 0.15, 0.20 and 0.25) of porous catalyst (alumina catalyst support, 10% 0.10m/s the volumetric mass transfer coefficient per unit volume, k L a/e G , was found to be practically independent of U and has values in the range 0.36-0.55 s -1 . From estimations of the sizes of the bubble size from literature correlation it is found that the large bubble mass transfer coefficient is about one order of magnitude higher than predicted by literature correlations.

Predictions from AUSRIVAS were used to compare macroinvertebrate data from samples collected over several years from two nearby river sites in the Hunter Valley Region in NSW, Australia. One of the sites was in agricultural land and the other one was in a National Park. Both sites had good water quality and a diverse range of macroinvertebrate habitats. The AUSRIVAS output most commonly used for assessing river condition is the Observed/Expected (O/E50) value. Only relatively common taxa, ie those that have greater than 50% probability of occurrence are included in the calculation of O/E50 values. T-tests used to test differences between the mean O/E50 values for the individual samples showed no significant differences between the two sites. When similar analyses were performed on outputs calculated using rare taxa, significant differences were found between the two sites for the riffle habitat but not for the edge habitat. Including the rare taxa in calculating AUSRIVAS outputs and utilising multiple-year outputs for assessing site condition may allow detection of impacts not detected by examining the commonly used outputs.