Cyclic hypoxia exposure accelerates the progression of amoebic gill disease

Amoebic gill disease (AGD), caused by the amoeba Neoparamoeba perurans, has led to considerable economic losses in every major Atlantic salmon producing country, and is increasing in frequency. The most serious infections occur during summer and autumn, when temperatures are high and poor dissolved oxygen (DO) conditions are most common. Here, we tested if exposure to cyclic hypoxia at DO saturations of 40–60% altered the course of infection with N. perurans compared to normoxic controls maintained at ≥90% DO saturation. Although hypoxia exposure did not increase initial susceptibility to N. perurans, it accelerated progression of the disease. By 7 days post-inoculation, amoeba counts estimated from qPCR analysis were 1.7 times higher in the hypoxic treatment than in normoxic controls, and cumulative mortalities were twice as high (16 ± 4% and 8 ± 2%), respectively. At 10 days post-inoculation, however, there were no differences between amoeba counts in the hypoxic and normoxic treatments, nor in the percentage of filaments with AGD lesions (control = 74 ± 2.8%, hypoxic = 69 ± 3.3%), or number of lamellae per lesion (control = 30 ± 0.9%, hypoxic = 27.9 ± 0.9%) as determined by histological examination. Cumulative mortalities at the termination of the experiment were similarly high in both treatments (hypoxic = 60 ± 2%, normoxic = 53 ± 11%). These results reveal that exposure to cyclic hypoxia in a diel pattern, equivalent to what salmon are exposed to in marine aquaculture cages, accelerated the progression of AGD in post-smolts

Tincurrin : a new biscuit wheat

Although a demand has existed both locally and overseas for soft wheat suitable for biscuits, cakes and various confectioneries, production has been very limited. In 1978 farmers in the soft wheat area will be able to grow the higher yielding variety Tincurrin. It is recommended for general sowing to replace all varieties grown at present in the soft wheat areas as defined.Exceptions may prevail in areas prone to rust snd septoria problems

Climatic controls on diffuse groundwater recharge across Australia

Reviews of field studies of groundwater recharge have attempted to investigate how climate characteristics control recharge, but due to a lack of data have not been able to draw any strong conclusions beyond that rainfall is the major determinant. This study has used numerical modelling for a range of Köppen-Geiger climate types (tropical, arid and temperate) to investigate the effect of climate variables on recharge for different soil and vegetation types. For the majority of climate types, the correlation between the modelled recharge and total annual rainfall is weaker than the correlation between recharge and the annual rainfall parameters reflecting rainfall intensity. Under similar soil and vegetation conditions for the same annual rainfall, annual recharge in regions with winter-dominated rainfall is greater than in regions with summer-dominated rainfall. The importance of climate parameters other than rainfall in recharge estimation is highest in the tropical climate type. Mean annual values of solar radiation and vapour pressure deficit show a greater importance in recharge estimation than mean annual values of the daily mean temperature. Climate parameters have the lowest relative importance in recharge estimation in the arid climate type (with cold winters) and the temperate climate type. For 75% of all soil, vegetation and climate types investigated, recharge elasticity varies between 2 and 4 indicating a 20% to 40% change in recharge for a 10% change in annual rainfall. Understanding how climate controls recharge under the observed historical climate allows more informed choices of analogue sites if they are to be used for climate change impact assessments

Surface water numerical modelling for the Clarence-Moreton bioregion. Product 2.6.1 from the Clarence-Moreton Bioregional Assessment

No abstract available

Surface water numerical modelling for the Clarence-Moreton bioregion. Product 2.6.1 from the Clarence-Moreton Bioregional Assessment

No abstract available

Radiofrequency ablation for the treatment of haemorrhoidal disease: a minimally invasive and effective treatment modality

BACKGROUND: Haemorrhoidal disease (HD) is a common colorectal condition that often requires surgical treatment. Less invasive procedures are usually more acceptable to patients. The aim of this study was to report the outcome of a novel and minimally invasive technique employing a radiofrequency ablation (RFA) energy (Rafaelo®) to treat HD. // METHODS: A total number of 27 patients who had RFA for the treatment of HD were recruited to this study. The procedure was performed under deep sedation and local anaesthesia. Patients' demographics; haemorrhoid severity score (HSS); quality of life; pain and satisfaction scores; and recurrence rate were recorded. // RESULTS: The mean age of the patients was 46 (SD 14) years, 18 (67%) males and 9 (33%) females. The mean body mass index was 25 (SD 4) kg/m2. The predominant symptom of all patients was per-rectal bleeding. HSS improved from 7.2 (SD 1.9) before the procedure to 1.6 (SD 1) after the procedure (p < 0.0001). Postoperative pain scores on a scale of 0-10 were 0, 2 (SD 2), 1 (SD 2), and 0 on immediate, day-1, day-3, and 2-month follow-up questionnaire. The mean satisfacion score was 9 (SD 1.5) out of 10 on 2-month follow-up. Mean time until patients returned to normal daily activity was 3 (SD 1) days following the procedure. Quality-of-life assessments including: visual analogue scale scores (before: mean 70, SD 23; after: mean 82, SD 16; p < 0.001) and EQ-5D-5L (before: mean 0.84, SD 0.15; after: mean 0.94, SD 0.13; p < 0.05) were significantly improved. The mean length of follow-up for recurrence of symptoms was 20 months (range 12-32 months). One patient (4%) reported the recurrence of rectal bleeding 12 months after the procedure. // CONCLUSIONS: RFA for the treatment of HD is safe and effective in achieving symptomatic relief. It is associated with minimal postoperative pain and low incidence of recurrence

Photosynthetic and growth response of freshwater picocyanobacteria are strain-specific and sensitive to photoacclimation

We investigated the effect of different light conditions on primary production and growth rates of three closely related freshwater picocyanobacterial strains from three different ribotypes in laboratory cultures. The primary goal was to test whether not only different pigment types (PC-rich versus PE-rich) but also other physiological characteristics suggested by different phylogenetic positions could affect growth and photosynthetic rates of picocyanobacteria. Secondly, we tested whether photacclimation is strain specific. Experiments were conducted over light intensities ranging from 6 to 1500 μmol photons m−2 s−1 with cultures that were acclimated to low (10 μmol photons m−2 s−1) and moderate (100 μmol photons m−2 s−1) irradiance. The PE-rich strain was sensitive to high light conditions and reached highest photosynthesis and growth rates at low light intensities. The relative effect of photoacclimation was different between the two PC-rich strains, with one strain showing only moderate changes in growth rates in response to the light level used during the acclimation period. Overall, growth rates differed widely in response to light intensity and photoacclimation. Photoacclimation significantly affected both primary production and growth rates of all three strains investigated. We conclude that strain-specific photoacclimation adds to the niche partitioning among closely related freshwater picocyanobacteria

Hadronic and Electromagnetic Interactions of Quarkonia

We examine the hadronic interactions of quarkonia, focusing on the decays psi(2s)->psi pi pi and upsilon(2s)-> upsilon pi pi. The leading gluonic operators in the multipole expansion are matched onto the chiral lagrangian with the coefficients fit to available data, both at tree-level and loop-level in the chiral expansion. A comparison is made with naive expectations loosely based on the large-$N_c$ limit of QCD in an effort to determine the reliability of this limit for other observables, such as the binding of \ps to nuclei. Crossing symmetry is used to estimate the cross-section for inelastic \pi\ps\to\pi\pss scattering, potentially relevant for heavy ion collisions. The radiative decays psi(2s)->psi pi pi gamma and upsilon(2s)-> upsilon pi pi gamma are determined at tree-level in the chiral lagrangian. Measurement of such decays will provide a test of the multipole and chiral expansions. We briefly discuss decays from the upsilon(3s) and also the contribution from pions to the electromagnetic polarizability of quarkonia.Comment: 20 pages, 11 figures, late

The transcriptional repressor bs69 is a conserved target of the e1a proteins from several human adenovirus species

Early region 1A (E1A) is the first viral protein produced upon human adenovirus (HAdV) infection. This multifunctional protein transcriptionally activates other HAdV early genes and reprograms gene expression in host cells to support productive infection. E1A functions by interacting with key cellular regulatory proteins through short linear motifs (SLiMs). In this study, the molecular determinants of interaction between E1A and BS69, a cellular repressor that negatively regulates E1A transactivation, were systematically defined by mutagenesis experiments. We found that a minimal sequence comprised of MPNLVPEV, which contains a conserved PXLXP motif and spans residues 112–119 in HAdV-C5 E1A, was necessary and sufficient in binding to the myeloid, Nervy, and DEAF-1 (MYND) domain of BS69. Our study also identified residues P113 and L115 as critical for this interaction. Furthermore, the HAdV-C5 and-A12 E1A proteins from species C and A bound BS69, but those of HAdV-B3,-E4,-D9,-F40, and-G52 from species B, E, D, F, and G, respectively, did not. In addition, BS69 functioned as a repressor of E1A-mediated transactivation, but only for HAdV-C5 and HAdV-A12 E1A. Thus, the PXLXP motif present in a subset of HAdV E1A proteins confers interaction with BS69, which serves as a negative regulator of E1A mediated transcriptional activation

Is there an aerosol signature of chemical cloud processing?

The formation of sulfate and secondary organic aerosol mass in the aqueous phase (aqSOA) of cloud and fog droplets can significantly contribute to ambient aerosol mass. While tracer compounds give evidence that aqueous-phase processing occurred, they do not reveal the extent to which particle properties have been modified in terms of mass, chemical composition, hygroscopicity, and oxidation state. We analyze data from several field experiments and model studies for six air mass types (urban, biogenic, marine, wild fire biomass burning, agricultural biomass burning, and background air) using aerosol size and composition measurements for particles 13–850&thinsp;nm in diameter. We focus on the trends of changes in mass, hygroscopicity parameter κ, and oxygen-to-carbon (O&thinsp;∕&thinsp;C) ratio due to chemical cloud processing. We find that the modification of these parameters upon cloud processing is most evident in urban, marine, and biogenic air masses, i.e., air masses that are more polluted than very clean air (background air) but cleaner than heavily polluted plumes as encountered during biomass burning. Based on these trends, we suggest that the mass ratio (Rtot) of the potential aerosol sulfate and aqSOA mass to the initial aerosol mass can be used to predict whether chemical cloud processing will be detectable. Scenarios in which this ratio exceeds Rtot ∼ 0.5 are the most likely ones in which clouds can significantly change aerosol parameters. It should be noted that the absolute value of Rtot depends on the considered size range of particles. Rtot is dominated by the addition of sulfate (Rsulf) in all scenarios due to the more efficient conversion of SO2 to sulfate compared to aqSOA formation from organic gases. As the formation processes of aqSOA are still poorly understood, the estimate of RaqSOA is likely associated with large uncertainties. Comparison to Rtot values as calculated for ambient data at different locations validates the applicability of the concept to predict a chemical cloud-processing signature in selected air masses.</p