220 research outputs found
Numerical investigation for the impact of CO2 geologic sequestration on regional groundwater flow
Large-scale storage of carbon dioxide in saline aquifers may cause considerable pressure perturbation and brine migration in deep rock formations, which may have a significant influence on the regional groundwater system. With the help of parallel computing techniques, we conducted a comprehensive, large-scale numerical simulation of CO{sub 2} geologic storage that predicts not only CO{sub 2} migration, but also its impact on regional groundwater flow. As a case study, a hypothetical industrial-scale CO{sub 2} injection in Tokyo Bay, which is surrounded by the most heavily industrialized area in Japan, was considered, and the impact of CO{sub 2} injection on near-surface aquifers was investigated, assuming relatively high seal-layer permeability (higher than 10 microdarcy). A regional hydrogeological model with an area of about 60 km x 70 km around Tokyo Bay was discretized into about 10 million gridblocks. To solve the high-resolution model efficiently, we used a parallelized multiphase flow simulator TOUGH2-MP/ECO2N on a world-class high performance supercomputer in Japan, the Earth Simulator. In this simulation, CO{sub 2} was injected into a storage aquifer at about 1 km depth under Tokyo Bay from 10 wells, at a total rate of 10 million tons/year for 100 years. Through the model, we can examine regional groundwater pressure buildup and groundwater migration to the land surface. The results suggest that even if containment of CO{sub 2} plume is ensured, pressure buildup on the order of a few bars can occur in the shallow confined aquifers over extensive regions, including urban inlands
Comparison and characterization of α-amylase inducers in Aspergillus nidulans based on nuclear localization of AmyR
AmyR, a fungal transcriptional activator responsible for induction of amylolytic genes in Aspergillus nidulans, localizes to the nucleus in response to the physiological inducer isomaltose. Maltose, kojibiose, and d-glucose were also found to trigger the nuclear localization of GFP-AmyR. Isomaltose- and kojibiose-triggered nuclear localization was not inhibited by the glucosidase inhibitor, castanospermine, while maltose-triggered localization was inhibited. Thus, maltose itself does not appear to be an direct inducer, but its degraded or transglycosylated product does. Non-metabolizable d-glucose analogues were also able to trigger the nuclear localization, implying that these sugars, except maltose, directly function as the inducers of AmyR nuclear entry. The inducing activity of d-glucose was 4 orders-of-magnitude weaker compared with isomaltose. Although d-glucose has the ability to induce α-amylase production, this activity would generally be masked by CreA-dependent carbon catabolite repression. Significant induction of α-amylase by d-glucose was observed in creA-defective A. nidulans
Serum homocysteine is weakly associated with von Willebrand factor and soluble vascular cell adhesion molecule 1, but not with C-reactive protein in type 2 diabetic and nondiabetic subjects: the Hoorn Study.
Background: Hyperhomocysteinaemia may constitute an independent risk factor for cardiovascular disease, but it is still unclear by which pathophysiological mechanisms homocysteine (tHcy) may promote atherothrombosis. The aim of this study was firstly to examine whether tHcy is associated with endothelial dysfunction, increased adherence of leukocytes, and/or chronic low-grade inflammation, as estimated from plasma levels of von Willebrand factor (vWf), soluble vascular cell adhesion molecule 1 (sVCAM-1) and C-reactive protein (CRP), respectively. Secondly we investigated whether the presence of type 2 diabetes modifies these associations. Materials and Methods: Six hundred and ten subjects of a general population of middle-aged and elderly subjects, 170 of whom had type 2 diabetes, participated in this cross-sectional study. Linear regression analyses were used to study whether tHcy was associated with vWf, sVCAM-1 and CRP, and whether the presence of diabetes modified these associations. Results: After adjustment for confounders, tHcy was significantly but weakly associated with vWf (β=0·15, P=0·05) and sVCAM-1 (β=0·082, P=0·04). tHcy was not significantly associated with CRP (β=0·02, P=0·91). The presence of diabetes did not significantly modify these associations. Conclusions: This study provides evidence that tHcy is, at most, weakly associated with endothelial dysfunction as estimated from plasma vWf, and with leukocyte adhesion as estimated from plasma sVCAM-1. tHcy was not significantly associated with chronic low-grade inflammation as estimated from plasma CRP. Our data thus suggest that the link between tHcy and atherothrombosis cannot be explained by associations of tHcy with vWf, sVCAM-1 or CRP
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The cascade of chaos: from early adversity to interpersonal aggression
We developed a cascade model to reconstruct the hypothesized developmental progression from (1) increased resource instability during childhood to (2) decreased maternal sensitivity during childhood to (3) social vulnerability cognitive schemata to (4) faster life history strategies to (5) decreased behavioral regulation to (6) more pronounced “Dark Triad” personalities to (7) higher levels of interpersonal aggression in adulthood. The hypothesized cascade model also evaluated the cross-cultural generality of this theoretically-specified developmental progression across a sampling of different societies: (1) the United States of America (N=144); (2) Mexico (N=118); (3) Brazil (N=1091, distributed across 3 data collection sites); (4) Sweden (N=144); and (5) the United Kingdom (N=260). Out of 21 interactive tests of the cross-cultural robustness of the main model parameters, only five reached statistical significance, and were relatively small in magnitude compared to their main effects. In no case did the magnitude and direction of the interaction completely reverse that of the corresponding main effect of the predictor, but merely either augmented or attenuated it somewhat across the affected study sites. We conclude that the results generally supported both the configural and metric invariance of the cascade model to a relatively high, albeit imperfect, degree
Managing (Un)certainty in the Japanese Antique Art Trade - How Economic and Social Factors Shape a Market
Market actors are commonly faced with solving three distinct coordination problems as sources of uncertainty. How should they value the objects of their trade, how can they shield themselves from the competition, and with whom and how do they cooperate? This article investigates how Japanese antique art dealers confront these issues. While offering a rich description and analysis of a hitherto understudied Japanese market, the article shows how economic and social issues are closely intertwined. It contributes to our understanding of behaviour in a Japanese market in three ways: Firstly, it underscores how inclusion/exclusion, status, reputation, networks and hierarchies constitute a field that allows market exchanges to exist in the first place, while also channelling, and being impacted by these market exchanges. Secondly, contrary to neoclassical economic theory, where the idea of value has largely been abandoned, the findings highlight the importance of distinguishing between notions of value and price in the understanding of markets. Thirdly, the article shows how market actors actively shape market arrangements to address the specific challenges of their domain. In the case of the Japanese antique art market these challenges include high risks of fakes, a limited quantity of high quality material, market outsiders, and dealers with deep pockets
Protective effects of a compound herbal extract (Tong Xin Luo) on free fatty acid induced endothelial injury: Implications of antioxidant system
<p>Abstract</p> <p>Background</p> <p>Tong-Xin-Luo (TXL) – a mixture of herbal extracts, has been used in Chinese medicine with established therapeutic efficacy in patients with coronary artery disease.</p> <p>Methods</p> <p>We investigated the protective role of TXL extracts on endothelial cells injured by a known risk factor – palmitic acid (PA), which is elevated in metabolic syndrome and associated with cardiovascular complications. Human aortic endothelial cells (HAECs) were preconditioned with TXL extracts before exposed to PA for 24 hours.</p> <p>Results</p> <p>We found that PA (0.5 mM) exposure induced 73% apoptosis in endothelial cells. However, when HAECs were preconditioned with ethanol extracted TXL (100 μg/ml), PA induced only 7% of the endothelial cells into apoptosis. Using antibody-based protein microarray, we found that TXL attenuated PA-induced activation of p38-MAPK stress pathway. To investigate the mechanisms involved in TXL's protective effects, we found that TXL reduced PA-induced intracellular oxidative stress. Through AMPK pathway, TXL restored the intracellular antioxidant system, which was depressed by the PA treatment, with an increased expression of thioredoxin and a decreased expression of the thioredoxin interacting protein.</p> <p>Conclusion</p> <p>In summary, our study demonstrates that TXL protects endothelial cells from PA-induced injury. This protection is likely mediated by boosting intracellular antioxidant capacity through AMPK pathway, which may account for the therapeutic efficacy in TXL-mediated cardiovascular protection.</p
The regulation and deregulation of Wnt signaling by PARK genes in health and disease
Wingless/Int (Wnt) signaling pathways are signal transduction mechanisms that have been widely studied in the field of embryogenesis. Recent work has established a critical role for these pathways in brain development, especially of midbrain dopaminergic neurones. However, the fundamental importance of Wnt signaling for the normal function of mature neurones in the adult central nervous system has also lately been demonstrated by an increasing number of studies. Parkinson's disease (PD) is the second most prevalent neurodegenerative disease worldwide and is currently incurable. This debilitating disease is characterized by the progressive loss of a subset of midbrain dopaminergic neurones in the substantia nigra leading to typical extrapyramidal motor symptoms. The aetiology of PD is poorly understood but work performed over the last two decades has identified a growing number of genetic defects that underlie this condition. Here we review a growing body of data connecting genes implicated in PD--most notably the PARK genes--with Wnt signaling. These observations provide clues to the normal function of these proteins in healthy neurones and suggest that deregulated Wnt signaling might be a frequent pathomechanism leading to PD. These observations have implications for the pathogenesis and treatment of neurodegenerative diseases in general
Similar NF-κB Gene Signatures in TNF-α Treated Human Endothelial Cells and Breast Tumor Biopsies
BACKGROUND: Endothelial dysfunction has been implicated in the pathogenesis of diverse pathologies ranging from vascular and immune diseases to cancer. TNF-α is one of the mediators of endothelial dysfunction through the activation of transcription factors, including NF-κB. While HUVEC (macrovascular cells) have been largely used in the past, here, we documented an NF-κB gene signature in TNFα-stimulated microvascular endothelial cells HMEC often used in tumor angiogenesis studies. METHODOLOGY/PRINCIPAL FINDINGS: We measured mRNA expression of 55 NF-κB related genes using quantitative RT-PCR in HUVEC and HMEC. Our study identified twenty genes markedly up-regulated in response to TNFα, including adhesion molecules, cytokines, chemokines, and apoptosis regulators, some of them being identified as TNF-α-inducible genes for the first time in endothelial cells (two apoptosis regulators, TNFAIP3 and TNFRSF10B/Trail R2 (DR5), the chemokines GM-CSF/CSF2 and MCF/CSF1, and CD40 and TNF-α itself, as well as NF-κB components (RELB, NFKB1 or 50/p105 and NFKB2 or p52/p100). For eight genes, the fold induction was much higher in HMEC, as compared to HUVEC. Most importantly, our study described for the first time a connection between NF-κB activation and the induction of most, if not all, of these genes in HMEC as evaluated by pharmacological inhibition and RelA expression knock-down by RNA interference. Moreover, since TNF-α is highly expressed in tumors, we further applied the NF-κB gene signature documented in TNFα-stimulated endothelial cells to human breast tumors. We found a significant positive correlation between TNF and the majority (85 %) of the identified endothelial TNF-induced genes in a well-defined series of 96 (48 ERα positive and 48 ERα negative) breast tumors. CONCLUSION/SIGNIFICANCE: Taken together these data suggest the potential use of this NF-κB gene signature in analyzing the role of TNF-α in the endothelial dysfunction, as well as in breast tumors independently of the presence of ERα
Reducing salt intake for prevention of cardiovascular diseases in high-risk patients by advanced health education intervention (RESIP-CVD study), Northern Thailand: study protocol for a cluster randomized trial
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