Characterisation of bacteria from the cultures of a Chlorella strain isolated from textile wastewater and their growth enhancing effects on the axenic cultures of Chlorella vulgaris in low nutrient media

There is increasing interest in the use of microalgae grown on wastewater to provide useful metabolites. Several bacteria have been shown to affect the growth rate and quality of the algae, but it is not clear if this is specific to a particular group of bacteria or if nutrient conditions can also influence this interaction. The bacterial community associated with a freshwater Chlorella sp. isolated from open pond textile factory wastewater was characterised and a diverse group of bacteria isolated. We provide evidence that nutrient concentrations affect bacterial community composition. When grown in BG11 medium, the community was dominated by Pseudomonas sp., but when grown in Chu 10 medium (which contains lower nitrogen and phosphorus), the relative abundance of a Brevundimonas spp. increased. Several of the bacteria isolated were able to influence the growth of an axenic Chlorella vulgaris culture. The Pseudomonas sp. had a negative effect in all media tested whereas several isolates enhanced C. vulgaris growth, but only in Chu 10 medium. This supports the theory that bacterial stimulation of algal growth is not limited to species-specific interactions but is influenced by environmental conditions. In low nutrient conditions, Chlorella sp. may be increasingly dependent on bacteria for growth

Legacy Effects of Canopy Disturbance on Ecosystem Functioning in Macroalgal Assemblages

Macroalgal assemblages are some of the most productive systems on earth and they contribute significantly to nearshore ecosystems. Globally, macroalgal assemblages are increasingly threatened by anthropogenic activities such as sedimentation, eutrophication and climate change. Despite this, very little research has considered the potential effects of canopy loss on primary productivity, although the literature is rich with evidence showing the ecological effects of canopy disturbance. In this study we used experimental removal plots of habitat-dominating algae (Order Fucales) that had been initiated several years previously to construct a chronosequence of disturbed macroalgal communities and to test if there were legacy effects of canopy loss on primary productivity. We used in situ photo-respirometry to test the primary productivity of algal assemblages in control and removal plots at two intertidal elevations. In the mid tidal zone assemblage, the removal plots at two sites had average primary productivity values of only 40% and 60% that of control areas after 90 months. Differences in productivity were associated with lower biomass and density of the fucoid algal canopy and lower taxa richness in the removal plots after 90 months. Low-shore plots, established three years earlier, showed that the loss of the large, dominant fucoid resulted in at least 50% less primary productivity of the algal assemblage than controls, which lasted for 90 months; other smaller fucoid species had recruited but they were far less productive. The long term reduction in primary productivity following a single episode of canopy loss of a dominant species in two tidal zones suggests that these assemblages are not very resilient to large perturbations. Decreased production output may have severe and long-lasting consequences on the surrounding communities and has the potential to alter nutrient cycling in the wider nearshore environment

The contribution of diet and genotype to iron status in women:a classical twin study

This is the first published report examining the combined effect of diet and genotype on body iron content using a classical twin study design. The aim of this study was to determine the relative contribution of genetic and environmental factors in determining iron status. The population was comprised of 200 BMI- and age-matched pairs of MZ and DZ healthy twins, characterised for habitual diet and 15 iron-related candidate genetic markers. Variance components analysis demonstrated that the heritability of serum ferritin (SF) and soluble transferrin receptor was 44% and 54% respectively. Measured single nucleotide polymorphisms explained 5% and selected dietary factors 6% of the variance in iron status; there was a negative association between calcium intake and body iron (p = 0.02) and SF (p = 0.04)

High survivability of micrometeorites on Mars: Sites with enhanced availability of limiting nutrients

NASA's strategy in exploring Mars has been to follow the water, because water is essential for life, and it has been found that there are many locations where there was once liquid water on the surface. Now perhaps, to narrow down the search for life on a barren basalt‐dominated surface, there needs to be a refocusing to a strategy of “follow the nutrients.” Here we model the entry of metallic micrometeoroids through the Martian atmosphere, and investigate variations in micrometeorite abundance at an analogue site on the Nullarbor Plain in Australia, to determine where the common limiting nutrients available in these (e.g., P, S, Fe) become concentrated on the surface of Mars. We find that dense micrometeorites are abundant in a range of desert environments, becoming concentrated by aeolian processes into specific sites that would be easily investigated by a robotic rover. Our modeling suggests that micrometeorites are currently far more abundant on the surface of Mars than on Earth, and given the far greater abundance of water and warmer conditions on Earth and thus much more active weather system, this was likely true throughout the history of Mars. Because micrometeorites contain a variety of redox sensitive minerals including FeNi alloys, sulfide and phosphide minerals, and organic compounds, the sites where these become concentrated are far more nutrient rich, and thus more compatible with chemolithotrophic life than most of the Martian surface. Plain Language Summary NASA's exploration program has allowed the scientific community to demonstrate clearly that Mars had a watery past, so the search for life needs to move on to identifying the places where water and nutrients coincided. We have investigated the relative abundance of micrometeorites on Mars compared to the Earth because these contain key nutrients that the earliest life forms on Earth used, and because their contained minerals can be used to investigate past atmospheric chemistry. We suggest that micrometeorites should be far more abundant on the Martian surface than on Earth's, and that wind‐driven modification of sediments is expected to concentrate micrometeorites, and their contained nutrients, in gravel beds and cracks in exposed bedrock

Modulation of Polar Lipid Profiles in Chlorella sp. in Response to Nutrient Limitation

We evaluate the effects of nutrient limitation on cellular composition of polar lipid classes/species in Chlorella sp. using modern polar lipidomic profiling methods (Liquid Chromatography-Tandem Mass Spectrometry; LC-MS/MS). Total polar lipid concentration was highest in nutrient-replete (HN) cultures with a significant reduction in monogalactosyldiacylglycerol (MGDG), phosphatidylglycerol (PG), phosphatidylcholine (PC) and phosphatidylethanolamine (PE) class concentrations for nutrient-deplete (LN) cultures. Moreover, reductions in the abundance of MGDG relative to total polar lipids versus an increase in the relative abundance of digalactosyldiacylglycerol (DGDG) were recorded in LN cultures. In HN cultures, polar lipid species composition remained relatively constant throughout culture with high degrees of unsaturation associated with acyl moieties. Conversely, in LN cultures lipid species composition shifted towards greater saturation of acyl moieties. Multivariate analyses revealed that changes in the abundance of a number of species contributed to the dissimilarity between LN and HN cultures but with dominant effects from certain species e.g. reduction in MGDG 34:7 (18:3/16:4). Results demonstrate that Chlorella sp. significantly alters its polar lipidome in response to nutrient limitation and this is discussed in terms of physiological significance and polar lipids production for applied microalgal production systems

Developing a local framework for quality in an online learning environment: a case study

This paper describes a quality framework for the development of a set of online learning resources, namely worked examples with audio enhancement and simulations, used to improve the offering of a level one business mathematics course at Central Queensland University. The framework centres around five criteria that emerged as the resources were developed. They were a primary reference determining the quality of the learning environment created

The pestivirus N terminal protease N(pro) redistributes to mitochondria and peroxisomes suggesting new sites for regulation of IRF3 by N(pro.)

The N-terminal protease of pestiviruses, N(pro) is a unique viral protein, both because it is a distinct autoprotease that cleaves itself from the following polyprotein chain, and also because it binds and inactivates IRF3, a central regulator of interferon production. An important question remains the role of N(pro) in the inhibition of apoptosis. In this study, apoptotic signals induced by staurosporine, interferon, double stranded RNA, sodium arsenate and hydrogen peroxide were inhibited by expression of wild type N(pro), but not by mutant protein N(pro) C112R, which we show is less efficient at promoting degradation of IRF3, and led to the conclusion that N(pro) inhibits the stress-induced intrinsic mitochondrial pathway through inhibition of IRF3-dependent Bax activation. Both expression of N(pro) and infection with Bovine Viral Diarrhea Virus (BVDV) prevented Bax redistribution and mitochondrial fragmentation. Given the role played by signaling platforms during IRF3 activation, we have studied the subcellular distribution of N(pro) and we show that, in common with many other viral proteins, N(pro) targets mitochondria to inhibit apoptosis in response to cell stress. N(pro) itself not only relocated to mitochondria but in addition, both N(pro) and IRF3 associated with peroxisomes, with over 85% of N(pro) puncta co-distributing with PMP70, a marker for peroxisomes. In addition, peroxisomes containing N(pro) and IRF3 associated with ubiquitin. IRF3 was degraded, whereas N(pro) accumulated in response to cell stress. These results implicate mitochondria and peroxisomes as new sites for IRF3 regulation by N(pro), and highlight the role of these organelles in the anti-viral pathway

What motivates British parents to consent for research? A questionnaire study

BACKGROUND: Informed consent is the backbone of a clinical trial. In children this is given by their parents. There have been many studies in the neonatal population but little is known about the views of the parents of infants and young children from within the United Kingdom. The objectives of this study were to assess what motivates parents to consent to a randomised clinical trial (RCT), their feelings on consent and participation and the factors that would influence their decision to take part in a future study. METHODS: The setting was a multi-centre randomised but non-blinded equivalence trial of oral versus intravenous (IV) treatment for community acquired pneumonia in previously well children aged 6 months to 16 years in the UK (PIVOT Study). Parents were sent a postal questionnaire at the end of the study which included open and closed-ended questions. Fishers Exact Test was used to analyse associations in non parametric categorical data. RESULTS: 243 children were recruited into the PIVOT study. Of a possible 235, 136 questionnaires were returned (response rate 59%). Of those questionnaires returned; 98% of parents remembered consenting, 95% felt they were given enough time to make their decision and 96% felt they received enough information. Major reasons for participation were benefit to other children in the future 31%, contribution to science 27%, benefit to their own child 18%. Most parents (85%) did not feel obliged to participate. 62% felt there was an advantage to taking part and 18% felt there was a disadvantage. 91% of parents said they would take part in a similar study in the future, stating influences on their decision being benefit to their own child (91%) and benefit to all children (89%). CONCLUSION: The major motivation in parents consenting for their previously well child to participate in an RCT of therapy for an acute medical illness was to increase medical knowledge in the future. Most saw an advantage in taking part in the trial and did not feel obliged to participate

DRAM-3 modulates autophagy and promotes cell survival in the absence of glucose

Macroautophagy is a membrane-trafficking process that delivers cytoplasmic constituents to lysosomes for degradation. The process operates under basal conditions as a mechanism to turnover damaged or misfolded proteins and organelles. As a result, it has a major role in preserving cellular integrity and viability. In addition to this basal function, macroautophagy can also be modulated in response to various forms of cellular stress, and the rate and cargoes of macroautophagy can be tailored to facilitate appropriate cellular responses in particular situations. The macroautophagy machinery is regulated by a group of evolutionarily conserved autophagy-related (ATG) proteins and by several other autophagy regulators, which either have tissue-restricted expression or operate in specific contexts. We report here the characterization of a novel autophagy regulator that we have termed DRAM-3 due to its significant homology to damage-regulated autophagy modulator (DRAM-1). DRAM-3 is expressed in a broad spectrum of normal tissues and tumor cells, but different from DRAM-1, DRAM-3 is not induced by p53 or DNA-damaging agents. Immunofluorescence studies revealed that DRAM-3 localizes to lysosomes/autolysosomes, endosomes and the plasma membrane, but not the endoplasmic reticulum, phagophores, autophagosomes or Golgi, indicating significant overlap with DRAM-1 localization and with organelles associated with macroautophagy. In this regard, we further proceed to show that DRAM-3 expression causes accumulation of autophagosomes under basal conditions and enhances autophagic flux. Reciprocally, CRISPR/Cas9-mediated disruption of DRAM-3 impairs autophagic flux confirming that DRAM-3 is a modulator of macroautophagy. As macroautophagy can be cytoprotective under starvation conditions, we also tested whether DRAM-3 could promote survival on nutrient deprivation. This revealed that DRAM-3 can repress cell death and promote long-term clonogenic survival of cells grown in the absence of glucose. Interestingly, however, this effect is macroautophagy-independent. In summary, these findings constitute the primary characterization of DRAM-3 as a modulator of both macroautophagy and cell survival under starvation conditions

EAES Recommendations for Recovery Plan in Minimally Invasive Surgery Amid COVID-19 Pandemic

Background: COVID-19 pandemic presented an unexpected challenge for the surgical community in general and Minimally Invasive Surgery (MIS) specialists in particular. This document aims to summarize recent evidence and experts’ opinion and formulate recommendations to guide the surgical community on how to best organize the recovery plan for surgical activity across diferent sub-specialities after the COVID-19 pandemic. Methods: Recommendations were developed through a Delphi process for establishment of expert consensus. Domain topics were formulated and subsequently subdivided into questions pertinent to diferent surgical specialities following the COVID-19 crisis. Sixty-fve experts from 24 countries, representing the entire EAES board, were invited. Fifty clinicians and six engineers accepted the invitation and drafted statements based on specifc key questions. Anonymous voting on the statements was performed until consensus was achieved, defned by at least 70% agreement. Results: A total of 92 consensus statements were formulated with regard to safe resumption of surgery across eight domains, addressing general surgery, upper GI, lower GI, bariatrics, endocrine, HPB, abdominal wall and technology/research. The statements addressed elective and emergency services across all subspecialties with specifc attention to the role of MIS during the recovery plan. Eighty-four of the statements were approved during the frst round of Delphi voting (91.3%) and another 8 during the following round after substantial modifcation, resulting in a 100% consensus. Conclusion: The recommendations formulated by the EAES board establish a framework for resumption of surgery following COVID-19 pandemic with particular focus on the role of MIS across surgical specialities. The statements have the potential for wide application in the clinical setting, education activities and research work across diferent healthcare systems