316 research outputs found
Influence of Gamma-Ray Emission on the Isotopic Composition of Clouds in the Interstellar Medium
We investigate one mechanism of the change in the isotopic composition of
cosmologically distant clouds of interstellar gas whose matter was subjected
only slightly to star formation processes. According to the standard
cosmological model, the isotopic composition of the gas in such clouds was
formed at the epoch of Big Bang nucleosynthesis and is determined only by the
baryon density in the Universe. The dispersion in the available cloud
composition observations exceeds the errors of individual measurements. This
may indicate that there are mechanisms of the change in the composition of
matter in the Universe after the completion of Big Bang nucleosynthesis. We
have calculated the destruction and production rates of light isotopes (D, 3He,
4He) under the influence of photonuclear reactions triggered by the gamma-ray
emission from active galactic nuclei (AGNs). We investigate the destruction and
production of light elements depending on the spectral characteristics of the
gamma-ray emission. We show that in comparison with previous works, taking into
account the influence of spectral hardness on the photonuclear reaction rates
can increase the characteristic radii of influence of the gamma-ray emission
from AGNs by a factor of 2-8. The high gamma-ray luminosities of AGNs observed
in recent years increase the previous estimates of the characteristic radii by
two orders of magnitude. This may suggest that the influence of the emission
from AGNs on the change in the composition of the medium in the immediate
neighborhood (the host galaxy) has been underestimated.Comment: 13 pages, 13 figures, 3 table
The effects of maintenance schedules following pulmonary rehabilitation in patients with chronic obstructive pulmonary disease: a randomised controlled trial.
OBJECTIVES: Pulmonary rehabilitation (PR) provides benefit for patients with chronic obstructive pulmonary disease (COPD) in terms of quality of life (QoL) and exercise capacity; however, the effects diminish over time. Our aim was to evaluate a maintenance programme for patients who had completed PR. SETTING: Primary and secondary care PR programmes in Norfolk. PARTICIPANTS: 148 patients with COPD who had completed at least 60% of a standard PR programme were randomised and data are available for 110 patients. Patients had greater than 20 pack year smoking history and less than 80% predicted forced expiratory volume in 1 s but no other significant disease or recent respiratory tract infection. INTERVENTIONS: Patients were randomised to receive a maintenance programme or standard care. The maintenance programme consisted of 2 h (1 h individually tailored exercise training and 1 h education programme) every 3 months for 1 year. PRIMARY AND SECONDARY OUTCOME MEASURES: The Chronic Respiratory Questionnaire (CRQ) (primary outcome), endurance shuttle walk test (ESWT), EuroQol (EQ5D), hospital anxiety and depression score (HADS), body mass index (BMI), body fat, activity levels (overall score and activity diary) and exacerbations were assessed before and after 12 months. RESULTS: There was no statistically significant difference between the groups for the change in CRQ dyspnoea score (primary end point) at 12 months which amounted to 0.19 (-0.26 to 0.64) units or other domains of the CRQ. There was no difference in the ESWT duration (-10.06 (-191.16 to 171.03) seconds), BMI, body fat, EQ5D, MET-minutes, activity rating, HADS, exacerbations or admissions. CONCLUSIONS: A maintenance programme of three monthly 2 h sessions does not improve outcomes in patients with COPD after 12 months. We do not recommend that our maintenance programme is adopted. Other methods of sustaining the benefits of PR are required. TRIAL REGISTRATION NUMBER: NCT00925171.This paper presents independent research funded by the National Institute for Health Research (NIHR) under its Research for Patient Benefit (RfPB) Programme (Grant Reference Number PB-PG-0408-16225). The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR or the Department of Health.This is the final published version. It first appeared at http://bmjopen.bmj.com/content/5/3/e005921.full?g=w_thorax_open_tab
Ecosystem-bedrock interaction changes nutrient compartmentalization during early oxidative weathering
Ecosystem-bedrock interactions power the biogeochemical cycles of Earth's
shallow crust, supporting life, stimulating substrate transformation, and
spurring evolutionary innovation. While oxidative processes have dominated half
of terrestrial history, the relative contribution of the biosphere and its
chemical fingerprints on Earth's developing regolith are still poorly
constrained. Here, we report results from a two-year incipient weathering
experiment. We found that the mass release and compartmentalization of major
elements during weathering of granite, rhyolite, schist and basalt was
rock-specific and regulated by ecosystem components.
A tight interplay between physiological needs of different biota, mineral
dissolution rates, and substrate nutrient availability resulted in intricate
elemental distribution patterns. Biota accelerated CO2 mineralization over
abiotic controls as ecosystem complexity increased, and significantly modified
stoichiometry of mobilized elements. Microbial and fungal components inhibited
element leaching (23.4% and 7%), while plants increased leaching and biomass
retention by 63.4%. All biota left comparable biosignatures in the dissolved
weathering products. Nevertheless, the magnitude and allocation of weathered
fractions under abiotic and biotic treatments provide quantitative evidence for
the role of major biosphere components in the evolution of upper continental
crust, presenting critical information for large-scale biogeochemical models
and for the search for stable in situ biosignatures beyond Earth.Comment: 41 pages (MS, SI and Data), 16 figures (MS and SI), 6 tables (SI and
Data). Journal article manuscrip
Ultramafic geoecology of South and Southeast Asia
Globally, ultramafic outcrops are renowned for hosting floras with high levels of endemism, including plants with specialised adaptations such as nickel or manganese hyperaccumulation. Soils derived from ultramafic regoliths are generally nutrient-deficient, have major cation imbalances, and have concomitant high concentrations of potentially phytotoxic trace elements, especially nickel. The South and Southeast Asian region has the largest surface occurrences of ultramafic regoliths in the world, but the geoecology of these outcrops is still poorly studied despite severe conservation threats. Due to the paucity of systematic plant collections in many areas and the lack of georeferenced herbarium records and databased information, it is not possible to determine the distribution of species, levels of endemism, and the species most threatened. However, site-specific studies provide insights to the ultramafic geoecology of several locations in South and Southeast Asia. The geoecology of tropical ultramafic regions differs substantially from those in temperate regions in that the vegetation at lower elevations is generally tall forest with relatively low levels of endemism. On ultramafic mountaintops, where the combined forces of edaphic and climatic factors intersect, obligate ultramafic species and hyperendemics often occur. Forest clearing, agricultural development, mining, and climate change-related stressors have contributed to rapid and unprecedented loss of ultramafic-associated habitats in the region. The geoecology of the large ultramafic outcrops of Indonesia’s Sulawesi, Obi and Halmahera, and many other smaller outcrops in South and Southeast Asia, remains largely unexplored, and should be prioritised for study and conservation
Opera and poison : a secret and enjoyable approach to teaching and learning chemistry
The storyline of operas, with historical or fictional characters, often include potions and poisons. This has prompted a study of the chemistry behind some operatic plots. The results were originally presented as a lecture given at the University of Minho in
Portugal, within the context of the International Year of Chemistry.
The same lecture was subsequently repeated at other universities as an invited lecture for science students and in public theaters for wider audiences. The lecture included a multimedia and interactive
content that allowed the audience to listen to arias and to watch video clips with selected scenes extracted from operas. The present article, based on the lecture, demonstrates how chemistry and opera
can be related and may also serve as a source of motivation and inspiration for chemistry teachers looking for alternative pedagogical approaches. Moreover, the lecture constitutes a vehicle that transports chemistry knowledge to wider audiences through examples of everyday molecules, with particular emphasis on natural products.The author is pleased to express his gratitude to Jorge Calado and Michael John Smith for useful discussions. The author also thanks the reviewers of the manuscript for their helpful comments and suggestions. Thanks are due to the Foundation for Science and Technology (FCT,Portugal), QREN and FEDER/EU for financial support through the research centers, CQ/UM PEst-C/QUI/UI0686/2011. Ciencia Viva, Portugal, is also acknowledged for financial support of the activities organized by the University of Minho during the International Year of Chemistry. The author also expresses his gratitude to Ana Paula Ferreira and Andre Cunha Leal from RTP Antena 2 who contributed immensely to the popularization of the lecture on which this paper is based on
The role of Prototyping in Ergonomic Practice and Research to Anticipate New Products and Services
This article argues for the dual role of prototyping in facilitating abductive thinking in research and practice within “Ergonomics” and “Design”. Moreover, this duality also pertains to the development of innovative commodities, as well as in the acquisition of new knowledge.
Since PE investigates real-life scenarios the aim of the researcher is to understand the nature and complexity of the future state of the system. In this sense prototypes can be used as probes into that future state due to the fact that once implemented they unveil real interactions and transformations of the system. Based on the act of design as a critical inquiry in itself, prototypes and prototyping are then being more and more perceived as carriers of reflection and argumentation
From a pedagogical perspective, prototyping exposes students to larger issues around creating and testing operational models of knowledge. Reversely, when being engaged in collaborative project with industry, prototyping can play an expanded as well as a more effective role in conceptualizing innovative solutions in an efficient manner.acceptedVersionPublisher embargo applies until August 13, 201
Combined approaches, including long-read sequencing, address the diagnostic challenge of HYDIN in primary ciliary dyskinesia
Primary ciliary dyskinesia (PCD), a disorder of the motile cilia, is now recognised as an underdiagnosed cause of bronchiectasis. Accurate PCD diagnosis comprises clinical assessment, analysis of cilia and the identification of biallelic variants in one of 50 known PCD-related genes, including HYDIN. HYDIN-related PCD is underdiagnosed due to the presence of a pseudogene, HYDIN2, with 98% sequence homology to HYDIN. This presents a significant challenge for Short-Read Next Generation Sequencing (SR-NGS) and analysis, and many diagnostic PCD gene panels do not include HYDIN. We have used a combined approach of SR-NGS with bioinformatic masking of HYDIN2, and state-of-the-art long-read Nanopore sequencing (LR_NGS), together with analysis of respiratory cilia including transmission electron microscopy and immunofluorescence to address the underdiagnosis of HYDIN as a cause of PCD. Bioinformatic masking of HYDIN2 after SR-NGS facilitated the detection of biallelic HYDIN variants in 15 of 437 families, but compromised the detection of copy number variants. Supplementing testing with LR-NGS detected HYDIN deletions in 2 families, where SR-NGS had detected a single heterozygous HYDIN variant. LR-NGS was also able to confirm true homozygosity in 2 families when parental testing was not possible. Utilising a combined genomic diagnostic approach, biallelic HYDIN variants were detected in 17 families from 242 genetically confirmed PCD cases, comprising 7% of our PCD cohort. This represents the largest reported HYDIN cohort to date and highlights previous underdiagnosis of HYDIN-associated PCD. Moreover this provides further evidence for the utility of LR-NGS in diagnostic testing, particularly for regions of high genomic complexity.</p
Combined approaches, including long-read sequencing, address the diagnostic challenge of HYDIN in primary ciliary dyskinesia
Primary ciliary dyskinesia (PCD), a disorder of the motile cilia, is now recognised as an underdiagnosed cause of bronchiectasis. Accurate PCD diagnosis comprises clinical assessment, analysis of cilia and the identification of biallelic variants in one of 50 known PCD-related genes, including HYDIN. HYDIN-related PCD is underdiagnosed due to the presence of a pseudogene, HYDIN2, with 98% sequence homology to HYDIN. This presents a significant challenge for Short-Read Next Generation Sequencing (SR-NGS) and analysis, and many diagnostic PCD gene panels do not include HYDIN. We have used a combined approach of SR-NGS with bioinformatic masking of HYDIN2, and state-of-the-art long-read Nanopore sequencing (LR_NGS), together with analysis of respiratory cilia including transmission electron microscopy and immunofluorescence to address the underdiagnosis of HYDIN as a cause of PCD. Bioinformatic masking of HYDIN2 after SR-NGS facilitated the detection of biallelic HYDIN variants in 15 of 437 families, but compromised the detection of copy number variants. Supplementing testing with LR-NGS detected HYDIN deletions in 2 families, where SR-NGS had detected a single heterozygous HYDIN variant. LR-NGS was also able to confirm true homozygosity in 2 families when parental testing was not possible. Utilising a combined genomic diagnostic approach, biallelic HYDIN variants were detected in 17 families from 242 genetically confirmed PCD cases, comprising 7% of our PCD cohort. This represents the largest reported HYDIN cohort to date and highlights previous underdiagnosis of HYDIN-associated PCD. Moreover this provides further evidence for the utility of LR-NGS in diagnostic testing, particularly for regions of high genomic complexity
The Vehicle, 1964, Vol. 6
Vol. 6
Table of Contents
Milepostspage 2
John Fitzgerald Kennedy Memorial Pagepage 4
Sadness No. 4 (Sorgen)Sherry S. Frypage 5
Christian BurialRoger J. Barrypage 7
The World of BeautyDavid Helmpage 9
The Song of the LarksDon Kapraunpage 10
ContrastKeith Haierpage 13
PanoramaDaun Alan Leggpage 13
A Child\u27s View of DeathCherie Brondellpage 14
RegretLiz Puckettpage 16
Brutal WarMary H. Soukuppage 17
aloneLiz Puckettpage 18
MadgeLinda Galeypage 19
Moon WatchingJoel E. Hendrickspage 20
AnalysisLiz Puckettpage 21
UniverseRick Talleypage 21
Anyone Can Be A LuniticRick Towsonpage 22
I, Too, Have A Rendezvous with DeathElaine Lancepage 23
The ReturnRobert D. Thomaspage 24
NamesLarry Gatespage 25
Eternal MomentsDavid Helmpage 25
The Last DaysPauline B. Smithpage 26
BeliefRichard J. Wiesepage 27
StormPauline B. Smithpage 28
ExplosionLiz Puckettpage 29
Autumn EveJoel E. Hendrickspage 29
The Girl On the White PonyLarry Gatespage 31
HoffnungTerry Michael Salempage 33
Stone WallsDaun Alan Leggpage 34
AdorationGail M. Barenfangerpage 37
MirageRoy L. Carlsonpage 38
Nature and NonsenseRick Talleypage 39
A Step Through A Looking GlassMarilyn Henrypage 40
Thoughts of a Summer PastPauline B Smithpage 42
Indiana GrassLarry Gatespage 43
RedondillaRoberta Matthewspage 44
Summer LoveDaun Alan Leggpage 45
To Youth Reaching For MaturityDavid Helmpage 45
Thanksgiving DayJoel E. Hendrickspage 46
Sadness No. 6 (Schatten)Sherry S. Frypage 48https://thekeep.eiu.edu/vehicle/1012/thumbnail.jp
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