Vitamin D and respiratory health Hughes, D.A; Norton, R
Clinical and experimental immunology,
October 2009, Letnik:
158, Številka:
1
Journal Article
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Vitamin D is now known to be of physiological importance outside of bone health and calcium homeostasis, and there is mounting evidence that it plays a beneficial role in the prevention and/or ...treatment of a wide range of diseases. In this brief review the known effects of vitamin D on immune function are described in relation to respiratory health. Vitamin D appears capable of inhibiting pulmonary inflammatory responses while enhancing innate defence mechanisms against respiratory pathogens. Population-based studies showing an association between circulating vitamin D levels and lung function provide strong justification for randomized controlled clinical trials of vitamin D supplementation in patients with respiratory diseases to assess both efficacy and optimal dosage.
•This paper presents an assessment of the key challenges of COVID-19 through an IS and IM lens.•The pandemic has forced governments and decision makers to reassess the use of IS and technology.•AI ...could engender better, more informed decision making during crisis management scenarios.•Privacy and security are key underlying concerns for many citizens during the pandemic.•In developing countries, the digital divide is most apparent due to social and cultural barriers.
The COVID-19 pandemic has forced many organisations to undergo significant transformation, rethinking key elements of their business processes and use of technology to maintain operations whilst adhering to a changing landscape of guidelines and new procedures. This study offers a collective insight to many of the key issues and underlying complexities affecting organisations and society from COVID-19, through an information systems and technological perspective. The views of 12 invited subject experts are collated and analysed where each articulate their individual perspectives relating to: online learning, digital strategy, artificial intelligence, information management, social interaction, cyber security, big data, blockchain, privacy, mobile technology and strategy through the lens of the current crisis and impact on these specific areas. The expert perspectives offer timely insight to the range of topics, identifying key issues and recommendations for theory and practice.
Organosulfates are secondary organic aerosol (SOA) products that form from
reactions of volatile organic compounds (VOC), such as isoprene, in the
presence of sulfate that is primarily emitted by ...fossil fuel combustion. This
study examines the anthropogenic influence on biogenic organosulfate
formation at an urban site in Atlanta, Georgia (GA) in the southeastern
United States (US). Organosulfates were analyzed in fine particulate matter
(PM2.5) collected during August 2015 in Atlanta using hydrophilic
interaction liquid chromatography (HILIC), tandem mass spectrometry (MS/MS),
and high-resolution time-of-flight (ToF) mass spectrometry. By their MS/MS
response, 32 major organosulfate species were identified, selected species
were quantified, and other species were semi-quantified using surrogate
standards. Organosulfates accounted for 16.5 % of PM2.5 organic carbon
(OC). Isoprene-derived organosulfates were the most abundant, dominated by
methyltetrol sulfate which accounted for 12.6 % of PM2.5 OC.
Together, the isoprene-derived organosulfates accounted for the majority of
the isoprene-derived SOA that had been previously observed in Atlanta, but
had not been identified at the molecular level. Other major species included
seven monoterpene-derived organosulfates, five diesel and/or
biodiesel-derived organosulfates, and three new organosulfates that are also
expected to derive from isoprene. Organosulfate species and concentrations in
Atlanta were compared to those in a rural forested site in Centreville,
Alabama (AL) during summer 2013, which were also dominated by
isoprene-derived organosulfates. In Atlanta, isoprene-derived organosulfate
concentrations were 2–6 times higher and accounted for twice as much
OC. The greatest enhancement in concentration was observed for
2-methylglyceric acid sulfate whose formation is enhanced in the presence of
nitrogen oxides (NO and NO2; NOx) and is a tracer for isoprene
high-NOx SOA. The isoprene-derived organosulfates indicated a stronger
influence of NOx in Atlanta compared to Centreville. Overall, these
results suggest that SOA in the southeastern US can be reduced by controlling
NOx and SO2 emissions from fossil fuel combustion. This study gives
insights into the major organosulfate species that should be targets for
future measurements in urban environments and standard development.
•Huge potential for marketers that implement AI, VR technologies.•Customer engagement behaviors and customer journeys enhanced via SMM.•Importance of ethical practice and explainability in use of AI ...and ML.•Trust is positively impacted via the cultivation of customer engagement.•eWOM overload can be mitigated by applying new tools and mechanisms.
The use of the internet and social media have changed consumer behavior and the ways in which companies conduct their business. Social and digital marketing offers significant opportunities to organizations through lower costs, improved brand awareness and increased sales. However, significant challenges exist from negative electronic word-of-mouth as well as intrusive and irritating online brand presence. This article brings together the collective insight from several leading experts on issues relating to digital and social media marketing. The experts’ perspectives offer a detailed narrative on key aspects of this important topic as well as perspectives on more specific issues including artificial intelligence, augmented reality marketing, digital content management, mobile marketing and advertising, B2B marketing, electronic word of mouth and ethical issues therein. This research offers a significant and timely contribution to both researchers and practitioners in the form of challenges and opportunities where we highlight the limitations within the current research, outline the research gaps and develop the questions and propositions that can help advance knowledge within the domain of digital and social marketing.
A twofold decrease to an unexplored scale of 5 nm was produced in Cu by applying a large sliding load in liquid nitrogen. Statistical and universal scaling analyses of deformation induced high angle ...boundaries, dislocation boundaries, and individual dislocations observed by high resolution electron microscopy reveal that dislocation processes still dominate. Dislocation based plasticity continues far below the transition suggested by experiment and molecular dynamics simulations, with a limit below 5 nm. Very high strength metals may emerge based on this enhanced structural refinement.
Abstract Cationic antimicrobial peptides (AMPs) are an intrinsic part of the human innate immune system. Over 100 different human AMPs are known to exhibit broad-spectrum antibacterial activity. ...Because of the increased frequency of resistance to conventional antibiotics there is an interest in developing AMPs as an alternative antibacterial therapy. Several cationic peptides that are derivatives of AMPs from the human innate immune system are currently in clinical development. There are also ongoing clinical studies aimed at modulating the expression of AMPs to boost the human innate immune response. In this review we discuss the potential problems associated with these therapeutic approaches. There is considerable experimental data describing mechanisms by which bacteria can develop resistance to AMPs. As for any type of drug resistance, the rate by which AMP resistance would emerge and spread in a population of bacteria in a natural setting will be determined by a complex interplay of several different factors, including the mutation supply rate, the fitness of the resistant mutant at different AMP concentrations, and the strength of the selective pressure. Several studies have already shown that AMP-resistant bacterial mutants display broad cross-resistance to a variety of AMPs with different structures and modes of action. Therefore, routine clinical administration of AMPs to treat bacterial infections may select for resistant bacterial pathogens capable of better evading the innate immune system. The ramifications of therapeutic levels of exposure on the development of AMP resistance and bacterial pathogenesis are not yet understood. This is something that needs to be carefully studied and monitored if AMPs are used in clinical settings.
It has long been known that mountain glaciers and continental ice sheets around the globe reached their respective maximum extent at different times during the last glacial cycle, often well before ...the global Last Glacial Maximum (LGM; c. 23–19ka), which is formally defined by peaks in global sea-level and marine oxygen isotope records. However, there is increasing evidence from around the world that it was not only mountain glaciers which were asynchronous with the global LGM but also some regions of the large continental glaciers. The Barents–Kara Ice Sheet in northern Eurasia together with a majority of ice masses throughout Asia and Australasia reached their maximum early in the last glacial cycle, a few thousand years before the global LGM period. The East Antarctic Ice Sheet also reached its maximum extent several millennia before the global LGM. In numerous mountainous regions at high-, mid- and low-latitudes across the world, glaciers reached their maximum extent before Marine Isotope Stage (MIS) 2, in MIS 5, 4 and 3. This is in contrast to most sectors of the Laurentide Ice Sheet, the Cordilleran Ice Sheet, the SE sector of the Fennoscandinavian Ice Sheet and the Alpine Ice Sheet in central Europe, which appear to have reached their maximum close to the global LGM in MIS 2. The diachronous maximum extents of both mountain glaciers and continental ice sheets during the last glacial cycle, means that the term and acronym Last Glacial Maximum (LGM) has limited chronostratigraphical meaning when correlating glacial deposits and landforms.
Water-soluble organic fluorophores are widely used as labels in biological systems. However, in many cases these fluorophores can interact strongly with lipid bilayers, influencing the interaction of ...the target with the bilayer and/or leading to misleading fluorescent signals. Here, we quantify the interaction of 32 common water-soluble dyes with model lipid bilayers to serve as an additional criterion when selecting a dye label.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Thermally induced bleaching has caused a global decline in corals and the frequency of such bleaching events will increase. Thermal bleaching severely disrupts the trophic behaviour of the coral ...holobiont, reducing the photosynthetically derived energy available to the coral host. In the short term this reduction in energy transfer from endosymbiotic algae results in an energy deficit for the coral host. If the bleaching event is short-lived then the coral may survive this energy deficit by depleting its lipid reserves, or by increasing heterotrophic energy acquisition. We show for the first time that the coral animal is capable of increasing the amount of heterotrophic carbon incorporated into its tissues for almost a year following bleaching. This prolonged heterotrophic compensation could be a sign of resilience or prolonged stress. If the heterotrophic compensation is in fact an acclimatization response, then this physiological response could act as a buffer from future bleaching by providing sufficient heterotrophic energy to compensate for photoautotrophic energy losses during bleaching, and potentially minimizing the effect of subsequent elevated temperature stresses. However, if the elevated incorporation of zooplankton is a sign that the effects of bleaching continue to be stressful on the holobiont, even after 11 months of recovery, then this physiological response would indicate that complete coral recovery requires more than 11 months to achieve. If coral bleaching becomes an annual global phenomenon by mid-century, then present temporal refugia will not be sufficient to allow coral colonies to recover between bleaching events and coral reefs will become increasingly less resilient to future climate change. If, however, increasing their sequestration of zooplankton-derived nutrition into their tissues over prolonged periods of time is a compensating mechanism, the impacts of annual bleaching may be reduced. Thus, some coral species may be better equipped to face repeated bleaching stress than previously thought.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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