55 research outputs found

    (Main Section: Ecological Planning)

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    Appropriate microclimate design for urban parks is important, as it impacts on thermal comfort and thereby influences the utilization of outdoor spaces by the public. Modifying the vegetation arrangement can improve the microclimate, especially under hot season conditions. However, it is difficult to measure microclimatic variations in the individual components within a park. Therefore, we combined in-situ measurements and a three-dimensional microclimate model ENVI-met, to examine variations in the microclimate of an urban neighborhood park in Seoul, Korea. Different vegetation arrangements were investigated with respect to their effects on microclimate and thermal comfort on a typical summer day. The study showed that: 1) the simulated results of ENVI-met were similar to the observed data, with an index of agreement of 0.69–0.88; 2) green spaces with multi-layered and dense canopy cover provided the most comfortable conditions. However, the cooling efficiency of vegetation may decrease when the plantation is too dense; and 3) the main factor affecting thermal comfort in the hot season was mean radiant temperature. The findings of this study provide useful information to guide planning of vegetation arrangements in future urban park designs

    (Main Section: Ecological Planning)

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    Sustainable spatial planning can be discussed in three categories based on the definition of sustainability; economic, social and ecological (environmental) aspects of planning. Therefore, having the perspective of ecological planning is a prerequisite to understanding all of the anthropogenic activities related to spatial development and conservation, at the local to global scales. To promote ecological planning concepts in practical cases, however, often faces conflict with economic and social benefits. This is the reason why our society still requires further evidence regarding the relevance of ecological planning and its way to incorporate with the existing planning context. This may be the responsibility of all researchers, planners, developers and administrators who are working with or for our environment

    Estimation of broad-leaved canopy growth in the urban forested area using multi-temporal airborne LiDAR datasets

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    Inter-annual canopy growth is one of the key indicators for assessing forest conditions, but the measurements require laborious field surveys. Up-to-date LiDAR remote sensing provides sufficient three-dimensional morphological information of the ground to monitor canopy heights on a broad scale. Thus, we attempted to use multi-temporal airborne LiDAR datasets in the estimation of vertical canopy growth, across various types of broad-leaved trees in a large urban park. The growth of broad-leaved canopies in the EXPO '70 urban forest in Osaka, Japan was assessed with 19 plots at the stand level and 39 selected trees at the individual-tree level. Airborne LiDAR campaigns repeatedly observed the park in the summers of 2004, 2008, and 2010. We acquired canopy height models (CHMs) for each year from the height values of the uppermost laser returns at every 0.5 m grid. The annual canopy growth was calculated by the differences in CHMs and validated with the annual changes in field-measured basal areas and tree heights. LiDAR estimations revealed that the average annual canopy growth from 2004 to 2010 was 0.26 ± 0.11 m m−2 yr−1 at the plot level and 0.26 ± 0.10 m m−2 yr−1 at the individual-tree level. This result showed that growing trends were consistent at different scales through 2004 to 2010 despite uncertainty in estimating short-term growth for small crown areas at the individual-tree level. This LiDAR-estimated canopy growth shows a moderate relation to field-measured increase of basal areas and average heights. The estimation uncertainties seem to result from the complex canopy structure and irregular crown shape of broad-leaved trees. Challenges still remain on how to incorporate the growth of understory trees, growth in the lateral direction, and gap dynamics inside the canopy, particularly in applying multi-temporal LiDAR datasets to the large-scale growth assessment

    (Main Section: Community Planning)

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    Urban ecosystem services (ESs) can moderate many common environmental issues in cities that are caused by the land use transformation central to urbanization. However, quantitative knowledge of historical changes in ES provisioning at various urban scales is limited. In this research, it is proposed to identify ESs, especially those generated by urban green space (UGS), and quantify their spatiotemporal variations at the regional scale in the southern part of Seoul City, Korea. Changes are first detected in landscape patterns, then one ES indicator — carbon sequestration (CS) — is chosen as a test case, and its spatial pattern explored using the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model. Total potential CS decreased by 41.2% from 1975 to 2015, with loss and fragmentation of landscapes occurring and patches becoming smaller and simpler in shape in the urban area, as indicated by landscape metrics. Moreover, strong decreases in urban forest and agricultural areas were the primary causes of loss of CS. On the other hand, a 120% increase in the grassland area somewhat offset these two factors. It is hoped that these results will contribute to cognizance of the potential of historical processes to inform future policy decisions related to green infrastructure and land-use planning

    The effect of alpha lipoic acid in a porcine in-stent restenosis model

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    SummaryBackgroundThe aim of this study was to investigate the effect of alpha lipoic acid (α-LA) on a porcine in-stent restenosis (ISR) model.MethodsIn protocol 1, porcine vascular smooth muscle cells (PVSMC) were stimulated by granulocyte-colony stimulating factor (G-CSF) in the presence or absence of α-LA. MTT (3-[4,5-dimethylthiazole-2-yl] 2,5-diphenyl tetrazolium bromide) assay and western blotting were used to determine the cell growth inhibitory rate and anti-inflammatory effect associated with nuclear factor-κb (NF-κb) and extracellular signal-regulated kinase (ERK). In protocol 2, 28 days after balloon overdilation injuries, 24 bare metal stents were placed in coronary artery of 12 pigs. The pigs were randomly divided to receive control diet with or without α-LA (100mg/kg). In protocol 3, 8 control stents and 8 α-LA coated stents were randomly implanted in 2 coronary arteries of 8 pigs and follow-up coronary angiogram and histopathologic assessment were performed 4 weeks after stenting.ResultsProtocol 1. The proliferation of PVSMC was inhibited and protein expression of NF-κb and ERK were attenuated by α-LA pretreatment. Protocol 2. On histopathologic analysis, the neointimal area (4.0±1.0mm2 vs. 1.5±0.7mm2, p<0.001) and histopathologic area of stenosis (66.7±10.7% vs. 24.2±9.7%, p<0.001) were reduced in the α-LA feeding group compared to controls. Protocol 3. On histopathologic analysis, the neointimal area (3.9±0.8mm2 vs. 1.0±0.4mm2, p<0.001), and the histopathologic area of stenosis (67.1±8.8% vs. 17.4±10.0%, p<0.001) were reduced in the α-LA coated stent group compared to the control stent group.Conclusionsα-LA feeding and α-LA coated stents inhibit neointimal hyperplasia in porcine ISR, possibly through inhibiting the activation of NF-κb pathway and proliferation of PVSMC

    Myocardial Infarction in a Young Man due to a Hypoplastic Coronary Artery

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    Hypoplastic coronary artery disease (HCAD) is a rare condition that may lead to myocardial infarction (MI) and sudden death. We discovered HCAD in a young man who developed chest pain after heavy drinking and who was found to have suffered an MI. His ECG showed ST-segment elevation with Q waves in the anterior leads, and echocardiography revealed apical dyskinesia with moderate left ventricular (LV) dysfunction. Coronary angiography showed hypoplasia of the left anterior descending (LAD) artery. 99mTc-tetrofosmin-gated myocardial perfusion scintigraphy showed a large, fixed perfusion defect in the anteroseptal and apical segments. Sixty-four-slice cardiac CT and cardiac MR imaging demonstrated thinning of the apical wall with calcification and delayed enhancement, supporting the diagnosis of long-standing MI. The patient was discharged symptom-free on medication for ischemic heart failure two weeks after admission. Although HCAD is very uncommon, it should be considered in children and young adults who suffer MI or sudden cardiac death

    A Long Road for Stem Cells to Cure Sick Hearts: Update on Recent Clinical Trials

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    The contribution of stem cells to cure damaged hearts has finally been unraveled. A large number of preclinical and clinical studies have showed beneficial outcomes after myocardial infarction. In this review, the current understanding of stem cell therapy in preclinical and clinical experiences is summarized. Stem cells from bone marrow have shown a potential to improve cardiac performance after myocardial infarction in animal and early clinical studies. Clinical trials from all over the world have provided safety assessments of stem cell therapy with marginal improvement of clinical outcomes. Thus, further investigations should be encouraged to resolve the discrepancies between studies, clinical issues, and unclear translational findings. This review provides information and commentary on key trials for stem cell-based treat-ment of cardiovascular disease

    Relation between Anemia and Vulnerable Coronary Plaque Components in Patients with Acute Coronary Syndrome: Virtual Histology-Intravascular Ultrasound Analysis

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    The aim of the present study was to evaluate the plaque components and the predictors of thin-cap fibroatheroma (TCFA) in anemic patients with acute coronary syndrome using virtual histology-intravascular ultrasound (VH-IVUS). Anemia was defined according to criteria of the World Health Organization, (i.e. , hemoglobin levels < 13 g/dL in men and < 12 g/dL in women) and we compared VH-IVUS findings between anemia group (171 patients, 260 lesions) and non-anemia group (569 patients, 881 lesions). Anemia group had greater % necrotic core (NC) volume (21% ± 9% vs 19% ± 9%, P = 0.001) compared with non-anemia group. Hemoglobin level correlated negatively with absolute NC volume (r = -0.235, P < 0.001) and %NC volume (r = -0.209, P < 0.001). Independent predictors of TCFA by multivariate analysis were diabetes mellitus (odds ratio [OR], 2.213; 95% confidence interval [CI], 1.403-3.612, P = 0.006), high-sensitivity C-reactive protein (OR, 1.143; 95% CI, 1.058-1.304, P = 0.012), microalbuminuria (albumin levels of 30 to 300 mg/g of creatinine) (OR, 2.124; 95% CI, 1.041-3.214, P = 0.018), and anemia (OR: 2.112; 95% CI 1.022-3.208, P = 0.028). VH-IVUS analysis demonstrates that anemia at the time of clinical presentation is associated with vulnerable plaque component in patients with acute coronary syndrome
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