3,172 research outputs found

    Beyond wasted and stunted—a major shift to fight child undernutrition

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    Child undernutrition refers broadly to the condition in which food intake is inadequate to meet a child's needs for physiological function, growth, and the capacity to respond to illness. Since the 1970s, nutritionists have categorised undernutrition in two major ways, either as wasted (ie, low weight for height, or small mid-upper arm circumference) or stunted (ie, low height for age). This approach, although useful for identifying populations at risk of undernutrition, creates several problems: the focus is on children who have already become undernourished, and this approach draws an artificial distinction between two idealised types of undernourished children that are widely interpreted as indicative of either acute or chronic undernutrition. This distinction in turn has led to the separation of programmatic approaches to prevent and treat child undernutrition. In the past 3 years, research has shown that individual children are at risk of both conditions, might be born with both, pass from one state to the other over time, and accumulate risks to their health and life through their combined effects. The current emphasis on identifying children who are already wasted or stunted detracts attention from the larger number of children undergoing the process of becoming undernourished. We call for a major shift in thinking regarding how we assess child undernutrition, and how prevention and treatment programmes can best address the diverse causes and dynamic biological processes that underlie undernutrition

    Electrically tunable Bragg gratings in single mode polymer optical fiber

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    We present what is to our knowledge the first demonstration of a tunable fiber Bragg grating device in polymer optical fiber that utilizes a thin-film resistive heater deposited on the surface of the fiber. The polymer fiber was coated via photochemical deposition of a Pd/Cu metallic layer with a procedure induced by vacuum-ultraviolet radiation at room temperature. The resulting device, when wavelength tuned via joule heating, underwent a wavelength shift of 2 nm for a moderate input power of 160 mW, a wavelength to input power coefficient of-13.4 pm/mW, and a time constant of 1.7 s-1

    Bridging the gap between omics and earth system science to better understand how environmental change impacts marine microbes

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    The advent of genomic-, transcriptomic- and proteomic-based approaches has revolutionized our ability to describe marine microbial communities, including biogeography, metabolic potential and diversity, mechanisms of adaptation, and phylogeny and evolutionary history. New interdisciplinary approaches are needed to move from this descriptive level to improved quantitative, process-level understanding of the roles of marine microbes in biogeochemical cycles and of the impact of environmental change on the marine microbial ecosystem. Linking studies at levels from the genome to the organism, to ecological strategies and organism and ecosystem response, requires new modelling approaches. Key to this will be a fundamental shift in modelling scale that represents micro-organisms from the level of their macromolecular components. This will enable contact with omics data sets and allow acclimation and adaptive response at the phenotype level (i.e. traits) to be simulated as a combination of fitness maximization and evolutionary constraints. This way forward will build on ecological approaches that identify key organism traits and systems biology approaches that integrate traditional physiological measurements with new insights from omics. It will rely on developing an improved understanding of ecophysiology to understand quantitatively environmental controls on microbial growth strategies. It will also incorporate results from experimental evolution studies in the representation of adaptation. The resulting ecosystem-level models can then evaluate our level of understanding of controls on ecosystem structure and function, highlight major gaps in understanding and help prioritize areas for future research programs. Ultimately, this grand synthesis should improve predictive capability of the ecosystem response to multiple environmental drivers

    Protected areas support more species than unprotected areas in Great Britain, but lose them equally rapidly

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    Protected areas are a key conservation tool, yet their effectiveness at maintaining biodiversity through time is rarely quantified. Here, we assess protected area effectiveness across sampled portions of Great Britain (primarily England) using regionalized (protected vs unprotected areas) Bayesian occupancy-detection models for 1238 invertebrate species at 1 km resolution, based on ~1 million occurrence records between 1990 and 2018. We quantified species richness, species trends, and compositional change (temporal beta diversity; decomposed into losses and gains). We report results overall, for two functional groups (pollinators and predators), and for rare and common species. Whilst we found that protected areas have 15 % more species on average than unprotected ones, declines in occupancy are of similar magnitude and species composition has changed 27 % across protected and unprotected areas, with losses dominating gains. Pollinators have suffered particularly severe declines. Still, protected areas are colonized by more locally-novel pollinator species than unprotected areas, suggesting that they might act as ‘landing pads’ for range-shifting pollinators. We find almost double the number of rare species in protected areas (although rare species trends are similar in protected and unprotected areas); whereas we uncover disproportionately steep declines for common species within protected areas. Our results highlight strong invertebrate reorganization and loss across both protected and unprotected areas. We therefore call for more effective protected areas, in combination with wider action, to bend the curve of biodiversity loss – where we provide a toolkit to quantify effectiveness. We must grasp the opportunity to effectively conserve biodiversity through time

    The multi-layered nature of the internet-based democratization of brand management

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    The evolution of the internet, including developments such as Web 2.0, has led to new relationship realities between organizations and their stakeholders. One manifestation of these complex new realities has been the emergence of an internet-based democratization of brand management. Research about this phenomenon has so far mainly focused on investigating just one or more individual themes and thereby disregarded the inherent multi-layered nature of the internet-based democratization of brand management as a holistic, socio-technological phenomenon. The aim of this paper is to address this limitation through an investigation of the various socio-technological democratization developments of the phenomenon. To achieve this aim, a balanced and stakeholder-oriented perspective on brand management has been adopted to conduct an integrative literature review. The review reveals three key developments, which together form the essential parts of the phenomenon: (I) the democratization of internet technology, (II) the democratization of information, and (III) the democratization of social capital. The insights gained help to clarify the basic structures of the multi-layered phenomenon. The findings contribute also to the substantiation of a call for a new brand management paradigm: one that takes not only company-initiated but also stakeholder-initiated brand management activities into accoun

    Sulfhydryl reactivity of human erythrocyte superoxide dismutase : On the origin of the unusual spectral properties of the protein when prepared by a procedure utilizing chloroform and ethanol for the precipitation of hemoglobin

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    1. 1.|During purification of human superoxide dismutase by the McCord-Fridovich procedure (McCord, J.M. and Fridovich, I. (1969) J. Biol. Chem. 244, 6049-6055) the `extra' sulfhydryl groups react with a variety of sulfur containing compounds including zero-valent sulfur to yield several dismutase fractions containing excess sulfur atoms and having a unique absorption band in the region of 325 nm. This is shown to be artefact of the purification procedure.2. 2.|Cysteine trisulfide and glutathione polysulfide were found to react with native human superoxide dismutase to yield derivatives having no reactive sulfhydryl groups and possessing spectral properties similar to the various fractions obtainable from the above purification procedure. A structure of the type protein-CH2-S-(S)nR is proposed to account for the results. The value of n is variable, and the additional sulfur reactive toward thiol reagents is thought to be due to persulfides (R = H). The 325 nm band is probably due to a n --> [sigma]ss* transition associated with a strained S-S bound.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/22486/1/0000027.pd
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