138 results match your criteria: "the University of St. Andrews[Affiliation]"

Diamondites: evidence for a distinct tectono-thermal diamond-forming event beneath the Kaapvaal craton.

Contrib Mineral Petrol

August 2019

6Geophysical Laboratory, Carnegie Institution of Washington, Washington, DC USA.

The petrogenesis and relationship of diamondite to well-studied monocrystalline and fibrous diamonds are poorly understood yet would potentially reveal new aspects of how diamond-forming fluids are transported through the lithosphere and equilibrate with surrounding silicates. Of 22 silicate- and oxide-bearing diamondites investigated, most yielded garnet intergrowths ( = 15) with major element geochemistry (i.e.

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Bacteria use small molecules called siderophores to scavenge iron. Siderophore-Fe complexes are recognised by outer-membrane transporters and imported into the periplasm in a process dependent on the inner-membrane protein TonB. The siderophore enterobactin is secreted by members of the family Enterobacteriaceae, but many other bacteria including Pseudomonas species can use it.

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Clinical Implication: Alzheimer's Disease (AD) presents as a gradual decline in cognitive function, with its characteristic pathology consisting of Amyloid β (Aβ) accumulation and hyperphosphorylated tau. Impaired insulin signalling was recently found in the brain in AD, and shown to increase AD pathology. Similar insulin resistance is found in type 2 diabetes and is currently treated with insulin sensitizers (IS).

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C-C chemokine receptor type 5 (CCR5) serves as a co-receptor for Human immunodeficiency virus (HIV), enabling the virus to enter human CD4 T cells and macrophages. In the absence of CCR5, HIV strains that require CCR5 (R5 or M-tropic HIV) fail to successfully initiate infection. Various natural mutations of the CCR5 gene have been reported to interfere with the HIV-CCR5 interaction, which influences the rate of AIDS progression.

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The detection of an object in the visual field requires the visual system to integrate a variety of local features into a single object. How these local processes and their global integration is influenced by the presence of other shapes in the visual field is poorly understood. The detectability (contour integration) of a central target object in the form of a two dimensional Gaborized contour was compared in the presence or absence of nearby surrounding objects.

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Tax and the Right to Health.

Health Hum Rights

December 2018

Senior lecturer in the Division of Infection and Global Health at the University of St. Andrews's, UK, and the College of Medicine, Blantyre, Malawi.

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New strategies are urgently required to develop antibiotics. The siderophore uptake system has attracted considerable attention, but rational design of siderophore antibiotic conjugates requires knowledge of recognition by the cognate outer-membrane transporter. is a serious pathogen, which utilizes (pre)acinetobactin to scavenge iron from the host.

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Temperature regimes have multiple spatial and temporal dimensions that have different impacts on biodiversity. Signatures of warming across these dimensions may contribute uniquely to the large-scale species redistributions and abundance changes that underpin community dynamics. A comprehensive review of the literature reveals that 86% of studies were focused on community responses to temperature aggregated over spatial or temporal dimensions (e.

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Cultural revolutions reduce complexity in the songs of humpback whales.

Proc Biol Sci

November 2018

Cetacean Ecology and Acoustics Laboratory, School of Veterinary Science, The University of Queensland, Gatton, Queensland 4343, Australia.

Much evidence for non-human culture comes from vocally learned displays, such as the vocal dialects and song displays of birds and cetaceans. While many oscine birds use song complexity to assess male fitness, the role of complexity in humpback whale () song is uncertain owing to population-wide conformity to one song pattern. Although songs change gradually each year, the eastern Australian population also completely replaces their song every few years in cultural 'revolutions'.

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Capsules are surface layers of hydrated capsular polysaccharides (CPSs) produced by many bacteria. The human pathogen serovar Typhi produces "Vi antigen" CPS, which contributes to virulence. In a conserved strategy used by bacteria with diverse CPS structures, translocation of Vi antigen to the cell surface is driven by an ATP-binding cassette (ABC) transporter.

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Muscarinic modulation of the Xenopus laevis tadpole spinal mechanosensory pathway.

Brain Res Bull

May 2018

School of Psychology and Neuroscience, the University of St Andrews, St Mary's Quad,South Street, St Andrews, Fife, KY16 9JP, UK. Electronic address:

Muscarinic acetylcholine receptors (mAChRs) mediate effects of acetylcholine (ACh) in many systems, including those involved in spinal functions like locomotion. In Xenopus laevis tadpoles at two days old, a model vertebrate for motor control research, we investigated the role of mAChRs in the skin mechanosensory pathway. We found that mAChR activation by carbachol did not affect the sensory Rohon-Beard neuron properties.

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Hummingbirds feed from hundreds of flowers every day. The properties of these flowers provide these birds with a wealth of information about colour, space and time to guide how they forage. To understand how hummingbirds might use this information, researchers have adapted established laboratory paradigms for use in the field.

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Viruses cause significant yield and quality losses in a wide variety of cultivated crops. Hence, the detection and identification of viruses is a crucial facet of successful crop production and of great significance in terms of world food security. Whilst the adoption of molecular techniques such as RT-PCR has increased the speed and accuracy of viral diagnostics, such techniques only allow the detection of known viruses, i.

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Peptide macrocycles are promising therapeutic molecules because they are protease resistant, structurally rigid, membrane permeable, and capable of modulating protein-protein interactions. Here, we report the characterization of the dual function macrocyclase-peptidase enzyme involved in the biosynthesis of the highly toxic amanitin toxin family of macrocycles. The enzyme first removes 10 residues from the N-terminus of a 35-residue substrate.

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Moving to the Next Phase of Reform.

J Law Med Ethics

December 2016

Stuart M. Butler, Ph.D., is a Senior Fellow in Economic Studies at the Brookings Institute. He is an Adjunct Professor at Georgetown's McCourt School of Public Policy and a Visiting Fellow at the Convergence Center for Policy Resolution. He serves as a member of the editorial board for Health Affairs, is a member of the Board on Health Care Services at the National Academy of Medicine and is part of the Advisory Group for the Academy of Medicine's Culture of Health Program. He holds a Bachelor of Science degree in physics and mathematics, a Master of Arts degree in economics and history, and a Ph.D. in American economic history, all from the University of St. Andrews (St. Andrews, UK).

Better health requires sectors like housing and education, and healthcare, to collaborate. That needs three strategies. Make full use of waivers to foster experimentation.

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Different Mutations in a P-type ATPase Transporter in Leishmania Parasites are Associated with Cross-resistance to Two Leading Drugs by Distinct Mechanisms.

PLoS Negl Trop Dis

December 2016

Centre de Recherche en Infectiologie du Centre de Recherche du CHU de Québec and Département de Microbiologie, Infectiologie et Immunologie, Faculté de Médecine, Université Laval, Québec, Québec, Canada.

Leishmania infantum is an etiological agent of the life-threatening visceral form of leishmaniasis. Liposomal amphotericin B (AmB) followed by a short administration of miltefosine (MF) is a drug combination effective for treating visceral leishmaniasis in endemic regions of India. Resistance to MF can be due to point mutations in the miltefosine transporter (MT).

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Bacterial polysaccharide synthesis and export.

Curr Opin Struct Biol

October 2016

Biomedical Science Research Complex, North Haugh, The University of St Andrews, St Andrews, United Kingdom. Electronic address:

All domains of life make carbohydrate polymers and by anchoring them to lipid molecules they can decorate the outside of the cell. Polysaccharides are linked to proteins by glycosylation, a process found in both bacteria and in higher organisms. Bacteria do have other distinct uses for carbohydrate polymers; in gram-negative bacteria glycolipids form the outer leaflet of the outer membrane and in many pathogens (both gram-positive and gram-negative) sugar polymers are used to build a capsule or are secreted into the environment.

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Southeast Asia is a biodiversity hotspot where the risk of extinction for many vertebrates is high (Duckworth et al. 2012) due to the loss and degradation of habitats resulting from burgeoning human populations and economies, expansion of agricultural development, and unsustainable harvest of wildlife and other natural resources (Sodhi et al. 2010).

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Zeolite-derived hybrid materials with adjustable organic pillars.

Chem Sci

June 2016

J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic , v.v.i., Dolejškova 3 , CZ-182 23 Prague 8 , Czech Republic . Email:

Porous organic-inorganic materials with tunable textural characteristics were synthesized using the top-down process by intercalating silsesquioxanes and polyhedral oligomeric siloxanes of different types between crystalline zeolite-derived layers. The influence of key parameters such as (i) linker nature (pure hydrocarbon, S-, N-containing); (ii) chain length in alkyl- and aryl bis(trialkoxysilyl) derivatives; (iii) denticity of the organic precursor molecules; (iv) nature and size of side chain in mono(trialkoxysilyl) substrates; (v) rigidity of the chain (saturated unsaturated, aliphatic aromatic); (vi) nature and size of leaving group on the structural and textural properties of formed hybrids was carefully addressed. It was established, that the optimal silsesquioxane appropriate for the formation of zeolite-derived hybrids with high textural characteristics should possess short alkyl or long aryl chains, relatively small leaving groups and denticity larger than 3.

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Environmental cost-benefit analysis has traditionally assumed that the value of benefits is sensitive to their timing and that outcomes are valued higher, the sooner in time they occur following implementation of a project or policy. Though, this assumption might have important implications especially for the social desirability of interventions aiming at counteracting time-persistent environmental problems, whose impacts occur in the long- and very long-term, respectively involving the present and future generations. This study analyzes the time sensitivity of social preferences for preservation policies of adaptation to climate change stresses.

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Zeolites are an important class of materials that have wide ranging applications such as heterogeneous catalysts and adsorbents which are dependent on their framework topology. For new applications or improvements to existing ones, new zeolites with novel pore systems are desirable. We demonstrate a method for the synthesis of novel zeolites using the ADOR route.

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Indo-Pacific Humpback Dolphins in Borneo: A Review of Current Knowledge with Emphasis on Sarawak.

Adv Mar Biol

May 2016

Yayasan Konservasi RASI, Rare Aquatic Species of Indonesia, Komplek Pandan Harum Indah, Samarinda, Kalimantan Timur, Indonesia.

Indo-Pacific humpback dolphins (Sousa chinensis) are documented from various locations along Borneo's coast, including three sites in Sarawak, Malaysia, three sites in Sabah, Malaysia, three locations in Kalimantan, Indonesia and the limited coastal waters of the Sultanate of Brunei. Observations in all these areas indicate a similar external morphology, which seems to fall somewhere between that documented for Chinese populations known as S. chinensis, and that of Sousa sahulensis in Australia and Papua New Guinea.

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Humpback Dolphins in Hong Kong and the Pearl River Delta: Status, Threats and Conservation Challenges.

Adv Mar Biol

May 2016

South China Sea Bio-Resource Exploitation and Utilization Collaborative Innovation Center, School of Marine Sciences, Sun Yat-Sen University, Guangzhou, PR China. Electronic address:

In coastal waters of the Pearl River Delta (PRD) region, the Indo-Pacific humpback dolphin (Sousa chinensis) is thought to number approximately 2500 individuals. Given these figures, the putative PRD population may appear strong enough to resist demographic stochasticity and environmental pressures. However, living in close proximity to the world's busiest seaport/airport and several densely populated urban centres with major coastal infrastructural developments comes with challenges to the long-term survival of these animals.

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Development of a handheld fluorescence imaging device to investigate the characteristics of protoporphyrin IX fluorescence in healthy and diseased skin.

Photodiagnosis Photodyn Ther

December 2015

Organic Semiconductor Centre, SUPA, School of Physics and Astronomy, The University of St Andrews, North Haugh, St Andrews, Fife KY16 9SS, UK. Electronic address:

Background: Topical Photodynamic therapy (PDT) is an effective treatment for superficial non-melanoma skin cancers (NMSC) and dysplasia. During PDT light activates the photosensitiser (PpIX), metabolised from a topical pro-drug. A combination of PpIX, light and molecular oxygen results in inflammation and cell death.

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