The effects of long-term drainage on processes governing CO2 und CH4 fluxes on an Arctic floodplain in Siberia

Arctic ecosystems have acted as a carbon sink, accumulating >1000 Pg of carbon in soils. However, increasing air temperatures and associated degradation of ice-rich permafrost in the Arctic hold the potential to modify soil topography and hydrology, with significant effects on carbon cycling. This study investigates how long-term drainage modifies ecosystem properties in an Arctic floodplain in northeastern Siberia, namely plant and microbial community structures and soil temperatures, and quantifies the net effects on CO2 and CH4 fluxes. Our study site has two areas in parallel: one that has been drained since 2004 and the other that has not been manipulated. A decade-long drainage decreased the abundance of cotton sedges, and consequently, tussock-forming sedges took the dominance. In addition, drainage increased soil temperatures at shallow layers due to lower heat capacity, but lowered them at deep layers due to lower thermal conductivity. Moreover, fractions of methanogens and methanotrophs were reduced following drainage. These changes in ecosystem properties considerably affected carbon cycle processes in multiple ways: 1) shifts in vegetation weakened CO2 uptake strength, and warmer surface soils accelerated CO2 emission rates; 2) a decrease in the abundance of aerenchymatous plants, changes in soil temperatures that potentially decrease methanogenesis rates and increase CH4 oxidation rates, and reduced fractions of CH4-associated microorganisms all contributed to a strong reduction in CH4 flux rates; and 3) CO2 and CH4 flux rates in the nongrowing season were higher in the drained area by four times and 10%, respectively, although the magnitude of fluxes was lower compared to the growing season. These findings emphasize the relevance of drainage effects for predicting Arctic ecosystems response to climate change, and the importance of long-term studies that include changes in ecosystem properties that affect CO2 and CH4 fluxes

Changes in intravenous hydration frequency and emergency department length of stay after implementation of oral ondansetron therapy in children with dehydration due to acute gastroenteritis

Purpose Oral ondansetron is a safe and effective antiemetic drug to facilitate oral rehydration therapy in acute gastroenteritis (AGE) with mild dehydration. We investigated the effect of oral ondansetron therapy on intravenous (IV) hydration frequency and emergency department length of stay (EDLOS) in dehydrated children with AGE. Methods We reviewed 15,813 children aged 12-60 months with primary diagnosis of AGE who visited a tertiary care university-affiliated hospital emergency department. The enrolled children were divided into the pre- (from January 2009 to June 2011) and post- (from January 2016 to June 2018) ondansetron groups according to the implementation of oral ondansetron therapy in the emergency department. As primary outcomes, IV hydration frequency, EDLOS, and hospitalization rate were compared between the 2 groups. As secondary outcomes, EDLOS and hospitalization rate were compared between the children in the post-ondansetron group who underwent the therapy, and those who did not. Results Of 7,990 enrolled children, 3,300 (41.3%) were designated as the post-ondansetron group, and among them 1,093 (33.1%) underwent oral ondansetron therapy. This group showed a lower IV hydration frequency, a shorter median EDLOS compared to the other group (61.9% vs. 55.8%, P < 0.001; 223.0 minutes vs. 175.0 minutes, P < 0.001, respectively), and a higher hospitalization rate (7.9% vs. 9.9%, P < 0.001). The children in the post-ondansetron group who underwent the therapy showed a shorter median EDLOS and a lower hospitalization rate compared to those who did not (142.0 vs 205.0 minutes, P < 0.001; 2.9% vs. 13.4%, P < 0.001, respectively). Conclusion Oral ondansetron therapy may reduce IV hydration frequency and EDLOS in dehydrated children with AGE, and can be considered in those having severe vomiting

H2B ubiquitylation enhances H3K4 methylation activities of human KMT2 family complexes

In mammalian cells, distinct H3K4 methylation states are created by deposition of methyl groups by multiple complexes of histone lysine methyltransferase 2 (KMT2) family proteins. For comprehensive analyses that directly compare the catalytic properties of all six human KMT2 complexes, we employed a biochemically defined system reconstituted with recombinant KMT2 core complexes (KMT2CoreCs) containing minimal components required for nucleosomal H3K4 methylation activity. We found that each KMT2CoreC generates distinct states and different levels of H3K4 methylation, and except for MLL3 all are stimulated by H2Bub. Notably, SET1BCoreC exhibited the strongest H3K4 methylation activity and, to our surprise, did not require H2B ubiquitylation (H2Bub); in contrast, H2Bub was required for the H3K4me2/3 activity of the paralog SET1ACoreC. We also found that WDR5, RbBP5, ASH2L and DPY30 are required for efficient H3K4 methyltransferase activities of all KMT2CoreCs except MLL3, which could produce H3K4me1 in the absence of WDR5. Importantly, deletion of the PHD2 domain of CFP1 led to complete loss of the H3K4me2/3 activities of SET1A/BCoreCs in the presence of H2Bub, indicating a critical role for this domain in the H2Bub-stimulated H3K4 methylation. Collectively, our results suggest that each KMT2 complex methylates H3K4 through distinct mechanisms in which individual subunits differentially participate

Production of He-4 and (4) in Pb-Pb collisions at root(NN)-N-S=2.76 TeV at the LHC

Results on the production of He-4 and (4) nuclei in Pb-Pb collisions at root(NN)-N-S = 2.76 TeV in the rapidity range vertical bar y vertical bar <1, using the ALICE detector, are presented in this paper. The rapidity densities corresponding to 0-10% central events are found to be dN/dy4(He) = (0.8 +/- 0.4 (stat) +/- 0.3 (syst)) x 10(-6) and dN/dy4 = (1.1 +/- 0.4 (stat) +/- 0.2 (syst)) x 10(-6), respectively. This is in agreement with the statistical thermal model expectation assuming the same chemical freeze-out temperature (T-chem = 156 MeV) as for light hadrons. The measured ratio of (4)/He-4 is 1.4 +/- 0.8 (stat) +/- 0.5 (syst). (C) 2018 Published by Elsevier B.V.Peer reviewe

25th annual computational neuroscience meeting: CNS-2016

The same neuron may play different functional roles in the neural circuits to which it belongs. For example, neurons in the Tritonia pedal ganglia may participate in variable phases of the swim motor rhythms [1]. While such neuronal functional variability is likely to play a major role the delivery of the functionality of neural systems, it is difficult to study it in most nervous systems. We work on the pyloric rhythm network of the crustacean stomatogastric ganglion (STG) [2]. Typically network models of the STG treat neurons of the same functional type as a single model neuron (e.g. PD neurons), assuming the same conductance parameters for these neurons and implying their synchronous firing [3, 4]. However, simultaneous recording of PD neurons shows differences between the timings of spikes of these neurons. This may indicate functional variability of these neurons. Here we modelled separately the two PD neurons of the STG in a multi-neuron model of the pyloric network. Our neuron models comply with known correlations between conductance parameters of ionic currents. Our results reproduce the experimental finding of increasing spike time distance between spikes originating from the two model PD neurons during their synchronised burst phase. The PD neuron with the larger calcium conductance generates its spikes before the other PD neuron. Larger potassium conductance values in the follower neuron imply longer delays between spikes, see Fig. 17.Neuromodulators change the conductance parameters of neurons and maintain the ratios of these parameters [5]. Our results show that such changes may shift the individual contribution of two PD neurons to the PD-phase of the pyloric rhythm altering their functionality within this rhythm. Our work paves the way towards an accessible experimental and computational framework for the analysis of the mechanisms and impact of functional variability of neurons within the neural circuits to which they belong

Glucoregulatory actions of leptin in rodent models of diabetes

The hormone leptin reduces food intake and increases energy expenditure; leptin deficient rodents and humans are severely obese with impaired glucose homeostasis, and leptin therapy reverses these metabolic abnormalities. Based on this, leptin gained significant interest as a potential therapeutic agent to combat obesity; however, it was soon discovered that most obese humans are resistant to its anorectic actions and the initial excitement over the therapeutic applicability of leptin dwindled. It is now evident that leptin regulates glucose metabolism independent of its actions on body weight. Underlining this, leptin displays the remarkable ability to reverse hyperglycemia in rodent models of type 1 diabetes. These findings sparked interest in leptin as a therapy for type 1 diabetes. The overarching goal of this thesis was to perform pre-clinical studies to elucidate the mechanism by which leptin lowers blood glucose levels in insulin deficient mice and assess whether resistance to these effects of leptin can occur. To this end, we assessed the plasma metabolomic profile of leptin-treated insulin deficient mice, which revealed global alterations in amino acid metabolism. Thus, we characterized amino acid utilization in leptin-treated mice, tested the mechanistic role of amino acid catabolism genes, and extensively characterized the metabolic changes in the liver using an 'omics' based approach. In addition, we assessed whether recapitulating leptin-mediated changes in the liver using a small molecule can mimic the glucose lowering actions of leptin. Lastly, we assessed whether hyperleptinemia or high-fat intake, which are reported to cause resistance to the weight reducing actions of leptin, also impede glucose lowering effects of leptin. This thesis revealed that leptin globally alters the liver metabolic profile to suppress the utilization of amino acids for glucose production and recapitulating the transcriptomic profile of leptin therapy with a novel small molecule can lower blood glucose levels in insulin deficient mice. Furthermore, dietary fats, but not hyperleptinemia, causes resistance to the glucose lowering actions of leptin in insulin deficient mice. Collectively, these investigations help elucidate the mechanism by which leptin reverses hyperglycemia in insulin deficient mice and shed insight into the suitability of leptin as a therapy for diabetes.Medicine, Faculty ofCellular and Physiological Sciences, Department ofGraduat

Exploring Categories of Self-Development of Novice Physical Education Teachers through Teacher Learning Community Activities

This study aims to discuss sustainable re-education of physical education teachers by deriving the types of self-development through novice physical education teachers&rsquo; experiences of teacher learning community activities. A qualitative research method was used with six physical education teachers from six middle schools located in the Seoul metropolitan area (Seoul, Gyeonggi, and Incheon) in Korea, from which the following types of self-development were obtained: The first category of self-development is &ldquo;to copy.&rdquo; They accept everything as new and follow along. The second category is &ldquo;to critique.&rdquo; They compare, analyze and criticize each other&rsquo;s classes with their community members. The third category is &ldquo;to share.&rdquo; They proactively share their ideas to transform &ldquo;what is mine&rdquo; into &ldquo;what is ours.&rdquo; The fourth category is &ldquo;to create.&rdquo; They build a new community that is suitable for them and create a process of giving and receiving help. In conclusion, we emphasized that teacher community learning activities of novice physical education teachers in Korea can provide an environment for the re-education of teachers that supports not only continuous self-development but also continuous professional development. As a follow-up study, we suggest a longitudinal study that will enable the understanding of physical education teachers&rsquo; continuous teacher learning community activities based on their stage of career growth as teachers. It will include a study on the continuity of re-education of physical education teachers according to the size of a teacher learning community or the relationships between members

Regeneration-associated macrophages: a novel approach to boost intrinsic regenerative capacity for axon regeneration

Axons in central nervous system (CNS) do not regenerate spontaneously after injuries such as stroke and traumatic spinal cord injury. Both intrinsic and extrinsic factors are responsible for the regeneration failure. Although intensive research efforts have been invested on extrinsic regeneration inhibitors, the extent to which glial inhibitors contribute to the regeneration failure in vivo still remains elusive. Recent experimental evidence has rekindled interests in intrinsic factors for the regulation of regeneration capacity in adult mammals. In this review, we propose that activating macrophages with pro-regenerative molecular signatures could be a novel approach for boosting intrinsic regenerative capacity of CNS neurons. Using a conditioning injury model in which regeneration of central branches of dorsal root ganglia sensory neurons is enhanced by a preceding injury to the peripheral branches, we have demonstrated that perineuronal macrophages surrounding dorsal root ganglia neurons are critically involved in the maintenance of enhanced regeneration capacity. Neuron-derived chemokine (C-C motif) ligand 2 (CCL2) seems to mediate neuron-macrophage interactions conveying injury signals to perineuronal macrophages taking on a soley pro-regenerative phenotype, which we designate as regeneration-associated macrophages (RAMs). Manipulation of the CCL2 signaling could boost regeneration potential mimicking the conditioning injury, suggesting that the chemokine-mediated RAM activation could be utilized as a regenerative therapeutic strategy for CNS injuries

Evaluating integrative medicine acute stroke inpatient care in South Korea

High demand for traditional Korean medicine led to a policy change in 2010 allowing hospitals to provide Integrative medicine care that combines Western medicine and Korean medicine. This study evaluated the effects of Integrative medicine compared to Western medicine-only for managing acute stroke in South Korean hospitals. A retrospective matched case-control observational study was conducted for acute stroke patients admitted nationwide in 2012 and 2013. Propensity score matching was used to adjust for the likelihood of selecting Integrative medicine. Hierarchical generalized linear models were used to control for patient characteristics at the episode of care (level 1) and cluster effects from the hospitals (level 2). A total of 1182 patients and 65 hospitals were matched and analyzed. Receiving Integrative medicine significantly increased the average length of stay (OR 1.27; 95% CI 1.13–1.42), total cost of inpatient care (OR 1.93; 95% CI 1.62–2.31), and per-day cost (OR 1.34; 95% CI 1.21–1.47). Receiving Integrative medicine did not affect all-cause 3-month emergency readmissions (OR 1.36; 95% CI 0.92–2.02). However, Integrative medicine was associated with a reduced risk of all-cause mortality at 3 months (OR 0.36; 90% CI 0.13–0.99) and 12 months (OR 0.34; 95% CI 0.15–0.75) after admission. Receiving Integrative medicine was associated with improved 3-month and 12-month survival, greater healthcare utilization and higher costs. Further economic evaluations are needed to guide policy for efficient integration of Korean medicine and Western medicine