77,539 research outputs found
Iron: the forgotten driver of nitrous oxide production in agricultural soil.
In response to rising interest over the years, many experiments and several models have been devised to understand emission of nitrous oxide (N2O) from agricultural soils. Notably absent from almost all of this discussion is iron, even though its role in both chemical and biochemical reactions that generate N2O was recognized well before research on N2O emission began to accelerate. We revisited iron by exploring its importance alongside other soil properties commonly believed to control N2O production in agricultural systems. A set of soils from California's main agricultural regions was used to observe N2O emission under conditions representative of typical field scenarios. Results of multivariate analysis showed that in five of the twelve different conditions studied, iron ranked higher than any other intrinsic soil property in explaining observed emissions across soils. Upcoming studies stand to gain valuable information by considering iron among the drivers of N2O emission, expanding the current framework to include coupling between biotic and abiotic reactions
Carbon dioxide level and form of soil nitrogen regulate assimilation of atmospheric ammonia in young trees.
The influence of carbon dioxide (CO2) and soil fertility on the physiological performance of plants has been extensively studied, but their combined effect is notoriously difficult to predict. Using Coffea arabica as a model tree species, we observed an additive effect on growth, by which aboveground productivity was highest under elevated CO2 and ammonium fertilization, while nitrate fertilization favored greater belowground biomass allocation regardless of CO2 concentration. A pulse of labelled gases ((13)CO2 and (15)NH3) was administered to these trees as a means to determine the legacy effect of CO2 level and soil nitrogen form on foliar gas uptake and translocation. Surprisingly, trees with the largest aboveground biomass assimilated significantly less NH3 than the smaller trees. This was partly explained by declines in stomatal conductance in plants grown under elevated CO2. However, unlike the (13)CO2 pulse, assimilation and transport of the (15)NH3 pulse to shoots and roots varied as a function of interactions between stomatal conductance and direct plant response to the form of soil nitrogen, observed as differences in tissue nitrogen content and biomass allocation. Nitrogen form is therefore an intrinsic component of physiological responses to atmospheric change, including assimilation of gaseous nitrogen as influenced by plant growth history
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Love fighting hate violence: an anti-violence program for martial arts and combat sports
This chapter outlines the Love Fighting Hate Violence (LFHV) project: an anti-violence initiative aimed at inspiring reflection and generating pedagogical interventions within martial arts and combat sports. The goal of LFHV is to harness the potential of these activities for educating people about violence, specifically with respect to understanding the principles of consent and violation. The chapter provides a theoretical overview of the project’s core philosophy by way of an interactionist reading of fights as social encounters. It then turns to discussing some of the practical materials already developed for use within LFHV. These draw on the aforementioned theory, as well as a values-based teaching methodology, to frame the potential contribution that this project can make to anti-violence education
Understanding sports violence: revisiting foundational explorations
Within this paper we discuss the importance of attending to definitions of ‘violence’. Through a return to a selection of important foundational works, we attempt to unpack the fundamental meanings of violence in a general sense, and sport violence in particular. With a specific focus on the need for definitional clarity, and particular attention to the ‘ritual’ dimensions of sport violence, we argue that engaging with these concepts is essential when conducting research in ‘violent’ contexts. Based on a critical reading of a small selection of relatively recent scholarship in sports settings, we ultimately argue that without careful consideration of what can constitute ‘violence’, scholars risk misrepresenting the social worlds they investigate. In conclusion we call for researchers to enter into a dialogue with foundational explorations of violence and to pays far greater heed to the definitions favoured by practitioners who engage with apparent ‘violence’ on a regular basis
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Nicholas Walters, boxing, and 'quitting': a case of the violence of interpretation
Mass storage technologies for libraries & information centres
To overcome growing requirements for additional space and for archival storage
of less used, old and important documents, libraries have been using compact or
dormitory storage and microfilming techniques. Of late, information technologies
have come to their rescue. Many technologies-magnetic as well as optical have
been tried for the past many years for mass storage of information. While magnetic
drum and tape are, heading towards obsolescence, optical' technologies with their
enormous storage capacities are trying to fill the gap.
This paper overviews the various 'technologies available for mass storage in the
library environment. The paper covers the magnetic storage devices including
magnetic tape, magnetic disc, cartridge tape and digital audio tape. The optical disc
storage technologies including read-only, write once read many and erasable/rewritable
media have been described. The role of optical discs in making electronic
publishing a popular technology has also been described. Future trends in the mass
storage technologies like volume holographic technology, electronic trap and
proximal probe technologies, and fluorescent multi-layered technology which are
under various stages of development have also been briefly discussed. Applications
of these technologies in library and information centres. have been listed
Serratiopeptidase reduces the invasion of osteoblasts by Staphylococcus aureus
Finding new strategies to counteract periprosthetic infection and implant failure is a main target in orthopedics. Staphylococcus aureus, the leading etiologic agent of orthopedic implant infections, is able to enter and kill osteoblasts, to stimulate pro-inflammatory chemokine secretion, to recruit osteoclasts, and to cause inflammatory osteolysis. Moreover, by entering eukaryotic cells, staphylococci hide from the host immune defenses and shelter from the extracellular antibiotics. Thus, infection persists, inflammation thrives, and a highly destructive osteomyelitis occurs around the implant. The ability of serratiopeptidase (SPEP), a metalloprotease by Serratia marcescens, to control S. aureus invasion of osteoblastic MG-63 cells and pro-inflammatory chemokine MCP-1 secretion was evaluated. Human osteoblast cells were infected with staphylococcal strains in the presence and in the absence of SPEP. Cell proliferation and cell viability were also evaluated. The release of pro-inflammatory chemokine MCP-1 was evaluated after the exposure of the osteoblast cells to staphylococcal strains. The significance of the differences in the results of each test and the relative control values was determined with Student’s t-test. SPEP impairs their invasiveness into osteoblasts, without affecting the viability and proliferation of bone cells, and tones down their production of MCP-1. We recognize SPEP as a potential tool against S. aureus bone infection and destruction
Evidence of a high incidence of subclinically affected calves in a herd of cattle with fatal cases of Bovine Neonatal Pancytopenia (BNP).
BACKGROUND: Bovine Neonatal Pancytopenia (BNP) is a disease of calves characterised by bone marrow trilineage hypoplasia, mediated by ingestion of alloantibodies in colostrum. Suspected subclinical forms of BNP have been reported, suggesting that observed clinical cases may not represent the full extent of the disease. However to date there are no objective data available on the incidence of subclinical disease or its temporal distribution. This study aimed to 1) ascertain whether subclinical BNP occurs and, if so, to determine the incidence on an affected farm and 2) determine whether there is evidence of temporal clustering of BNP cases on this farm. To achieve these aims, haematological screening of calves born on the farm during one calving season was carried out, utilising blood samples collected at defined ages. These data were then analysed in comparison to data from both known BNP-free control animals and histopathologically confirmed BNP cases. An ordinal logistic regression model was used to create a composite haematology score to predict the probabilities of calves being normal, based on their haematology measurements at 10–14 days old. RESULTS: This study revealed that 15% (21 of 139) of the clinically normal calves on this farm had profoundly abnormal haematology (<5% chance of being normal) and could be defined as affected by subclinical BNP. Together with clinical BNP cases, this gave the study farm a BNP incidence of 18%. Calves with BNP were found to be distributed throughout the calving period, with no clustering, and no significant differences in the date of birth of cases or subclinical cases were found compared to the rest of the calves. This study did not find any evidence of increased mortality or increased time from birth to sale in subclinical BNP calves but, as the study only involved a single farm and adverse effects may be determined by other inter-current diseases it remains possible that subclinical BNP has a detrimental impact on the health and productivity of calves under certain circumstances. CONCLUSIONS: Subclinical BNP was found to occur at a high incidence in a herd of cattle with fatal cases of BNP
Do frailty and comorbidity indices improve risk prediction of 28-day ED reattendance? Reanalysis of an ED discharge nomogram for older people
Background: In older people, quantification of risk of reattendance after emergency department (ED) discharge is important to provide adequate post ED discharge care in the community to appropriately targeted patients at risk.
Methods: We reanalysed data from a prospective observational study, previously used for derivation of a nomogram for stratifying people aged 65 and older at risk for ED reattendance. We investigated the potential effect of comorbidity load and frailty by adding the Charlson or Elixhauser comorbidity index and a ten-item frailty measure from our data to develop four new nomograms. Model I and model F built on the original nomogram by including the frailty measure with and without the addition of the Charlson comorbidity score; model E adapted for efficiency in the time-constrained environment of ED was without the frailty measure; and model P manually constructed in a purposeful stepwise manner and including only statistically significant variables. Areas under the ROC curve of models were compared. The primary outcome was any ED reattendance within 28 days of discharge.
Results: Data from 1357 patients were used. The point estimate of the respective areas under ROC were 0.63 (O), 0.63 (I), 0.68 (E), 0.71 (P) and 0.63 (F).
Conclusion: Addition of a comorbidity index to our previous model improves stratifying elderly at risk of ED reattendance. Our frailty measure did not demonstrate any additional predictive benefit
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