The biodiversity benefits of kelp aquaculture and afforestation are increasingly acclaimed as the industry continues to grow and develop globally, however, whether farmed kelp can provide this ...ecosystem service remains unclear. Using peer-reviewed literature, we evaluated whether kelp farms provide biodiversity benefits, and identified only 23 studies that discussed the effects of kelp aquaculture on biodiversity, half of which were broad reviews that only assessed the concept of ‘biodiversity’ peripherally (e.g. did not focus on specific responses or taxa). There is also a general lack of experimental research on the topic. Based on the evidence, it seems that kelp farms can create habitat via changes to the local environment, particularly through the provision of structure and changed nutrient cycling. While this can lead to increased abundance and diversity among certain taxa (e.g. fouling organisms), it seems that kelp farms typically create novel habitats that support distinct communities not equivalent to natural kelp forests. Moreover, the potential for kelp farms to support biodiversity depends on a range of operational factors, many of which may be at odds with farming objectives that require the harvest and removal of the habitat that farms provide. While more work needs to be done to address the complexity of comparisons between kelp farms and forests, especially at appropriate experimental scales, it currently seems unlikely that kelp farms will act as kelp forests and deliver meaningful biodiversity outcomes. We should instead recognise farms for providing their own valuable services and support restoration and conservation practices of kelp forests to pursue biodiversity outcomes.
Kelp forests provide habitat for many species, but it remains uncertain whether specific kelp forest types support distinct biodiversity. Surface canopy-forming giant kelp (
Macrocystis pyrifera
) ...forests in Tasmania, Australia, have declined significantly due to climate change, and have been widely replaced by forests dominated by smaller stipitate kelps like
Ecklonia radiata
. However, there is limited knowledge of the community composition of
Macrocystis
forests and how this may differ from the stipitate kelp forest community. Underwater visual census surveys were conducted of the fishes and macroinvertebrates (> 2.5 cm length) in remnant
Macrocystis
forests in south-eastern Tasmania, and in adjacent stipitate kelp forests. 18 sites (9 of each forest type) were surveyed across two regions during the period of peak growth and canopy cover (i.e. winter-spring). Faunal community composition varied little between forest types, although
Macrocystis
forests supported more than double the abundance and biomass of mobile fishes, while cryptic fishes differed by forest type depending on region. Macroinvertebrate assemblages did not differ between forest types nor regions. Thus, for the taxa and time period examined, Tasmanian
Macrocystis
and stipitate kelp forests supported mostly similar faunal communities. Kelp forest communities showed spatial variation and were also likely influenced by a variety of other habitat characteristics, such as the relatively small patch sizes and/or ephemeral state of the remnant
Macrocystis
forests. Quantifying the community structure of these endangered communities informs the ecological changes that have occurred and will serve as an important reference for ongoing conservation and restoration activities.
Marine kelp forests cover 1/3 of our world's coastlines, are heralded as a nature-based solution to address socio-environmental issues, connect hundreds of millions of people with the ocean, and ...support a rich web of biodiversity throughout our oceans. But they are increasingly threatened with some areas reporting over 90% declines in kelp forest cover in living memory. Despite their importance and the threats they face, kelp forests are entirely absent from the international conservation dialogue. No international laws, policies, or targets focus on kelp forests and very few countries consider them in their national policy. The Kelp Forest Challenge addresses that gap. Together with 252 kelp experts, professionals, and citizens from 25 countries, the Kelp Forest Challenge was developed as a grassroots vision of what the world can achieve for kelp forest conservation. It is a global call to restore 1 million and protect 3 million hectares of kelp forests by 2040. This is a monumental challenge, that will require coordination across multiple levels of society and the mobilization of immense resources. Pledges may therefore include area for protection or restoration, enabling pledges which assist in conservation (funding, equipment, professional expertise, capacity building), or awareness-based pledges which increase awareness or education about kelp forests. Correspondingly, participants may be from government, scientific institutions, private sector, NGOs, community groups, or individuals. This challenge is the beginning of a 17-year mission to save our kelp forests and anyone and any organisation is invited to participate.
In a text designed for students and health professionals, the broad base of nutrition knowledge is presented. With an emphasis on total health promotion, section 1 examines the practical aspects of ...normal nutrition, for example, sound eating habits, guidelines for food planning and purchasing, and the safe storage and preparation of nutritious food. Section 2 deals with the contribution of nutrients to body structure and function, considering such topics as metabolism and the roles of nutrients as fuel; regulators; and agents of body maintenance, repair, and growth. Section 3 guides the student in the development of skills for the provision of nutritional care, while section 4 covers diet therapy from a physiological perspective. Appendices include detailed information on Federal nutrition programs, tables of food composition, and a food guide for modified diets
The enzyme α-isopropylmalate synthase (IPMS) catalyses the reaction between acetyl coenzyme A (AcCoA) and α-ketoisovalerate (KIV) to produce free coenzyme A and α isopropylmalate (IPM). This reaction ...is a key control point in the biosynthesis of a leucine, a pathway absent in animals but present in plants, fungi and bacteria. As a result, IPMS is a antibiotic and herbicidal target that has been validated by knockout studies for M. tuberculosis, the causative agent of tuberculosis. Engineered IPMSs have also been used in the fermentative production of long chain alcohols for use as fuels.
IPMS belongs to a family of related enzymes called α-ketoacid: AcCoA re-aldolases (KARAs), with each subfamily differing in the specific α-ketoacid that AcCoA is reacted with. The known KARA subfamilies are IPMS, citramalate synthases (CMSs), homocitrate synthases (HCSs), methylthioalkylmalate synthases (MAMSs) and re-citrate synthases (RCSs), respectively involved in the biosynthesis of isoleucine, lysine, glucosinolates and TCA cycle intermediates.
This thesis describes work aimed at improving understanding of both specific subfamilies of KARA enzymes and also the genetic and functional relationships between the subfamilies. A particular emphasis is placed on relating primary structure to function, allowing the inference of function from a very small subset of residues.
IPMSs are divided into two classes, the Mtu-like IPMSs and the much less studied Eco-like IPMSs. Chapter 2 details the expression and characterisation of the Eco like IPMS from N. meningitidis (NmeIPMS). Overall NmeIPMS showed similar properties to MtuIPMS, but unlike that enzyme NmeIPMS is inhibited by high divalent metal ion concentrations, does not require monovalent metal ions, and shows some activity with the α-ketoacid 3-methyl α ketovalerate. Several previous results showing inhibitory activity of Zn2+, Cd2+ and bromopyruvate were also found to be the results of interference with the assay system and all three were found to be much weaker inhibitors than previously determined.
Phylogenetic analysis of the different KARA subfamilies revealed certain specific positions that were believed to control substrate specificity. Chapter 3 details mutagenesis experiments on MtuIPMS that probe the function of these residues. Once the importance of the residues had been established, substitutions were made in which IPMS residues were replaced with their equivalents from HCSs and CMSs in order to change substrate specificity. The most successful result was the Y169L substitution based on HCS, which decreased the specificity constant with KIV by four orders of magnitude while improving other activities, successfully shifting the best activity to the unbranched α-ketoacid α-ketobutyrate.
Chapter 4 of this thesis details the purification and functional testing of the RCS from C. saccharolyticus (CscRCS), the first thermophilic RCS characterised. CscRCS was found to have an extremely low Km for its substrate oxaloacetate (1.7 µM), believed to be an adaptation to the instability of oxaloacetate at the temperatures CscRCS operates at in vivo. The enzyme also showed competitive affinity by α-ketoglutarate, the end product of the pathway. Unlike other characterised RCSs, CscRCS showed no oxygen sensitivity.
The phylogenetic analysis conducted for this thesis identified a subfamily of KARAs dubbed pseudo-IPMSs (PIPMSs) that showed no substantial homology to any studied subfamily. In Chapter 5 the PIPMS from T. thermophilus (TthPIPMS) was expressed and characterised. TthPIPMS showed many features of a CMS, being most active with the same substrate (pyruvate) and sensitive to the same inhibitor (isoleucine). Unlike the previously studied CMS subfamilies, TthPIPMS possesses a nanomolar IC50 for its inhibitor, and also shows substantial activity as an RCS.
The results of these chapters are then drawn together in Chapter 6 to create a picture of the relationships between the KARA enzymes, in terms of their functional characteristics as well as the sequence and evolutionary relationships between them that have bought about their diverse functions.
This thesis describes an action research investigation of improvements to instruction in General Chemistry at Purdue University. Specifically, the study was conducted to guide continuous reform of ...curriculum materials delivered via the World Wide Web by involving students, instructors, and curriculum designers. The theoretical framework for this study was based upon constructivist learning theory and knowledge claims were developed using an inductive analysis procedure. This results of this study are assertions made in three domains: learning chemistry content via the World Wide Web, learning about learning via the World Wide Web, and learning about participation in an action research project. In the chemistry content domain, students were able to learn chemical concepts that utilized 3-dimensional visualizations, but not textual and graphical information delivered via the Web. In the learning via the Web domain, the use of feedback, the placement of supplementary aids, navigation, and the perception of conceptual novelty were all important to students' use of the Web. In the participation in action research domain, students learned about the complexity of curriculum. development, and valued their empowerment as part of the process.
Summary
Background
Autochthonous (locally acquired) hepatitis E is increasingly recognised in developed countries, and is thought to be a porcine zoonosis. A range of extra‐hepatic manifestations of ...hepatitis E infection have been described, but have never been systematically studied.
Aim
To report the extra‐hepatic manifestations of hepatitis E virus.
Methods
Retrospective review of data of 106 cases of autochthonous hepatitis E (acute n = 105, chronic n = 1).
Results
Eight (7.5%) cases presented with neurological syndromes, which included brachial neuritis, Guillain‐Barré syndrome, peripheral neuropathy, neuromyopathy and vestibular neuritis. Patients with neurological syndromes were younger (median age 40 years, range 34–92 years, P = 0.048) and had a more modest transaminitis (median ALT 471 IU/L, P = 0.015) compared to cases without neurological symptoms median age 64 years (range 18–88 years), median ALT 1135 IU/L. One patient presented with a cardiac arrhythmia,twelve patients (11.3%) presented with thrombocytopenia, fourteen (13.2%) with lymphocytosis and eight (7.5%) with a lymphopenia, none of which had any clinical consequence. Serum electrophoresis was performed in 65 patients at presentation, of whom 17 (26%) had a monoclonal gammopathy of uncertain significance. Two cases developed haematological malignancies, acute myeloid leukaemia and duodenal plasmacytoma, 18 and 36 months after presenting with acute hepatitis E infection.
Conclusions
A range of extra‐hepatic manifestations can occur with hepatitis E. Neurological and haematological features of hepatitis E infection are relatively frequent in this UK cohort, and result in significant morbidity which warrants further study.
Abstract Background In a prospective, multicenter, randomized controlled trial, 4,146 patients were randomized to receive standard care or standard care plus coronary computed tomography angiography ...(CCTA). Objectives The purpose of this study was to explore the consequences of CCTA-assisted diagnosis on invasive coronary angiography, preventive treatments, and clinical outcomes. Methods In post hoc analyses, we assessed changes in invasive coronary angiography, preventive treatments, and clinical outcomes using national electronic health records. Results Despite similar overall rates (409 vs. 401; p = 0.451), invasive angiography was less likely to demonstrate normal coronary arteries (20 vs. 56; hazard ratios HRs: 0.39 95% confidence interval (CI): 0.23 to 0.68; p < 0.001) but more likely to show obstructive coronary artery disease (283 vs. 230; HR: 1.29 95% CI: 1.08 to 1.55; p = 0.005) in those allocated to CCTA. More preventive therapies (283 vs. 74; HR: 4.03 95% CI: 3.12 to 5.20; p < 0.001) were initiated after CCTA, with each drug commencing at a median of 48 to 52 days after clinic attendance. From the median time for preventive therapy initiation (50 days), fatal and nonfatal myocardial infarction was halved in patients allocated to CCTA compared with those assigned to standard care (17 vs. 34; HR: 0.50 95% CI: 0.28 to 0.88; p = 0.020). Cumulative 6-month costs were slightly higher with CCTA: difference $462 (95% CI: $303 to $621). Conclusions In patients with suspected angina due to coronary heart disease, CCTA leads to more appropriate use of invasive angiography and alterations in preventive therapies that were associated with a halving of fatal and non-fatal myocardial infarction. (Scottish COmputed Tomography of the HEART Trial SCOT-HEART; NCT01149590 )
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