The lack of long-term PM2.5 measurements in developing countries makes it difficult to quantify the overall PM2.5 pollution exposures and health impacts in these countries where the PM2.5 ...concentrations are often very high. Moreover, it is also difficult for traditional fixed-site monitoring to capture the substantial spatial variability of PM2.5 over dense urban areas or regions with significant topography. Hence, recent developments in satellite-based remote-sensing allowing the reconstruction of long-term, wide-area and high-resolution estimates of current and historical PM2.5 concentration is an important step forward, allowing the quantification of the long-term pollution exposure of PM2.5 in developing cities and in dense urban areas using the satellite-derived PM2.5 data. In this study, instead of just looking at the spatial average PM2.5 concentrations, we have studied the long-term population exposure of PM2.5 by analyzing the population-weighted PM2.5 concentrations at regional, city and district scales by combining 1km×1km satellite-derived PM2.5 and population density data sets. The variation of population exposure to PM2.5 across the urban areas in the Pearl River Delta (PRD) region from 2000 to 2014 was studied. Our result shows that the PM2.5 concentrations over the PRD increased steadily from 2000 to 2004, remained at quite a high level through 2008 and then started to decline after 2009. More importantly, our analysis also shows that, at regional, city and district levels, the population-weighted mean PM2.5 concentrations from data with 1km resolutions are typically the highest, followed by the population-weighted mean PM2.5 concentrations from data with 10km resolutions and then the simple spatial PM2.5 averages. This suggests that the use of simple spatial concentrations can lead to systematic underestimation of the overall population exposure and the associated health impacts. This systematic difference is related to the positive correlation between PM2.5 pollutant concentration and population density, and shows the usefulness of using high-resolution satellite-retrieved PM2.5 concentrations to quantify the overall population exposure. The higher population-weighted mean PM2.5 concentration in comparison with simple spatial average indicates that, for more effective reduction of overall population exposure and protection of public health, control efforts must be further targeted at high-population high-pollution areas, and land-use and city planning should also encourage population to redistribute away from the highly polluted areas.
•PM2.5 in 15years with high spatial resolution of 1-km was derived from MODIS.•Study the long-term exposure (E) to PM2.5 on the regional, city and district scales•Decrease the spatial correlation between PM2.5 and population density can reduce E.•Long-term exposure will be systematic underestimated with lower resolution datasets.•Control efforts must be targeted in high-pollution and high-population density areas.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
A new naphthalene-2(3
H
)-one, yuzhenone (
1
), was isolated from the seed shells of
Michelia champaca
L. (Magnoliaceae). The structure of the new naphthalene-2(3
H
)-one derivative was elucidated by ...chemical and physical evidence.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
A new ketone, volubilisone (
1
), was isolated from the seed shells of
Plukenetia volubilis
L. (Euphorbiaceae). The structure of the new 4-hydroxy-4-methoxybutan-2-one derivative was elucidated by ...chemical and physical evidence.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
• Water-mediated fertilization is ubiquitous in early land plants. This ancestral mode of fertilization has, however, generally been considered to have been lost during the evolutionary history of ...terrestrial flowering plants.
• We investigated reproductive mechanisms in the subtropical ginger Cautleya gracilis (Zingiberaceae), which has two pollen conditions – granular and filiform masses – depending on external conditions. We tested whether rain transformed granular pollen into filiform masses and whether this then promoted pollen-tube growth and fertilization of ovules. Using experimental manipulations in the field we investigated the contribution of water-mediated fertilization to seed production.
• Rain caused granular pollen to form filiform masses of germinating pollen tubes, which transported sperm to ovules, resulting in fertilization and seed set. Flowers exposed to rain produced significantly more seeds than those protected from the rain, which retained granular pollen. Insect pollination made only a limited contribution to seed set because rainy conditions limited pollinator service.
• Our results reveal a previously undescribed fertilization mechanism in flowering plants involving water-mediated fertilization stimulated by rain. Water-mediated fertilization is likely to be adaptive in the subtropical monsoon environments in which C. gracilis occurs by ensuring reproductive assurance when persistent rain prevents insect-mediated pollination.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NMLJ, NUK, OILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
•Develop an automatic indoor thermal comfort and energy consumption optimization algorithm.•Integrate CFD simulation tool, back-propagation neural network (BPNN) and adaptive grey wolf optimizer ...(GWO) algorithm.•High predictive accuracy of the BPNN-based adaptive GWO model.•The BPNN-based adaptive GWO algorithm has low computational consumption and strong ability to automatically balance the indoor thermal comfort and energy consumption.
Heating ventilation and air conditioning (HVAC) systems provide a comfortable indoor thermal environment, but in the process of attaining appropriate indoor thermal comfort levels, they usually entail high energy consumptions. It is therefore imperative to balance thermal comfort value with energy consumption. However, such research currently faces two problems: one, it is difficult to obtain accurate parameters pertaining to the indoor environment of buildings, particularly near heat source areas; two, it is the diametrical nature of having to simultaneously maintain thermal comfort and keep energy consumption low. Therefore, this study aims to propose a rapid thermal comfort level prediction and optimization algorithm, as well as a method to minimize the energy consumption using only a computational fluid dynamic (CFD) database that is compact in size. Firstly, CFD is used to implement the database that stores data on indoor airflow and temperature distributions of different building structures and indoor conditions. Next, using the database as a basis, a back-propagation neural network (BPNN) is developed to predict the thermal comfort level. The adaptive grey wolf optimizer (GWO) algorithm is then applied to optimize the thermal comfort value, and the latest control methods: the artificial neural network (ANN)-genetic algorithm (GA) and ANN-particle swarm optimizer (PSO) algorithm are compared against the BPNN-based adaptive GWO method. The results show that the BPNN-based adaptive GWO algorithm can rapidly predict the thermal comfort level and have strong optimization ability. Meanwhile, 1.01% of energy savings are achieved.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
A new apocarotenoid, fasciculatol (
1
) was isolated from the stems of
Capsicum annuum
var. fasciculatum (Sturtev.) Irish (Solanaceae). The structure of the new apocarotenoid was elucidated by ...chemical and physical evidence.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Controlled blasting for loosening coal seams is one of the most important measures to enhance gas drainage and thus prevent coal and gas outbursts. The formation and development of blasting-induced ...damage zone, as well as the gas flow in damaged coal seams, can be considered as a coupled process among gas flow, solid deformation and damage. In this work, a coupled multiphysical model for the interaction between blasting damage of coal seam and gas flow is proposed, based on which, the effect of destress blasting on draining gas in coal seam is numerically simulated and the associated mechanisms for enhanced gas drainage induced by blasting damage are clarified. The loosening of coal seam induced by blasting is considered as a damage process that is dominated by the combined contribution of blasting stress wave and blasting-induced gas pressure, in this respect, the blasting damage of rock and coal seam is numerically simulated and compared with the existing experimental observations. Then, by considering the effect of coal seam damage on the gas permeability, the gas drainage enhanced by blasting damage is quantified based on the numerical simulations. It is demonstrated that the blasting damage around the borehole can not only alleviate the stress concentration at the perimeter of the borehole but also enhance the gas drainage due to the increase of the gas permeability in the damaged coal seam.
► A coupled coal–gas interaction model before and after destress blasting is proposed. ► Evolution of damaged and permeability after destress blasting is numerically examined. ► The coalbed gas drainage enhanced by destress blasting is numerically quantified.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Compared with young children who have acute lymphoblastic leukaemia (ALL), adolescents with ALL have unfavourable disease profiles and worse survival. However, limited data are available regarding ...the characteristics and outcomes of adolescents with ALL who underwent treatment in clinical trials. The aim of this study was to investigate the causes of treatment failure in adolescents with ALL.
We retrospectively analysed the outcomes of 711 children with ALL, aged 1-18 years, who were enrolled in five clinical trials of paediatric ALL treatment between 1993 and 2015.
Among the 711 children with ALL, 530 were young children (1-9 years at diagnosis) and 181 were adolescents (including 136 younger adolescents 10-14 years and 45 older adolescents 15-18 years). Compared with young children who had ALL, adolescents with ALL were less likely to have favourable genetic features and more likely to demonstrate poor early response to treatment. The 10-year overall survival and event-free survival rates were significantly lower among adolescents than among young children (77.9% vs 87.6%, P=0.0003; 69.7% vs 76.5%, P=0.0117). There were no significant differences in the 10-year cumulative incidence of relapse, but the 10-year cumulative incidence of treatment-related death (TRD) was significantly greater among adolescents (7.2%) than among young children (2.3%; P=0.002). Multivariable analysis showed that both younger and older adolescents (vs young children) had worse survival and greater incidence of TRD.
Adolescents with ALL had worse survival because they experienced a greater incidence of TRD. There is a need to investigate optimal treatment adjustments and novel targeted agents to achieve better survival rates (without excessive toxicity) among adolescents with ALL.
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FFLJ, NUK, ODKLJ, UL, UM, UPUK
Objective
To investigate whether hemodynamic features of symptomatic intracranial atherosclerotic stenosis (sICAS) might correlate with the risk of stroke relapse, using a computational fluid ...dynamics (CFD) model.
Methods
In a cohort study, we recruited patients with acute ischemic stroke attributed to 50 to 99% ICAS confirmed by computed tomographic angiography (CTA). With CTA‐based CFD models, translesional pressure ratio (PR = pressurepoststenotic/pressureprestenotic) and translesional wall shear stress ratio (WSSR = WSSstenotic − throat/WSSprestenotic) were obtained in each sICAS lesion. Translesional PR ≤ median was defined as low PR and WSSR ≥4th quartile as high WSSR. All patients received standard medical treatment. The primary outcome was recurrent ischemic stroke in the same territory (SIT) within 1 year.
Results
Overall, 245 patients (median age = 61 years, 63.7% males) were analyzed. Median translesional PR was 0.94 (interquartile range IQR = 0.87–0.97); median translesional WSSR was 13.3 (IQR = 7.0–26.7). SIT occurred in 20 (8.2%) patients, mostly with multiple infarcts in the border zone and/or cortical regions. In multivariate Cox regression, low PR (adjusted hazard ratio HR = 3.16, p = 0.026) and high WSSR (adjusted HR = 3.05, p = 0.014) were independently associated with SIT. Patients with both low PR and high WSSR had significantly higher risk of SIT than those with normal PR and WSSR (risk = 17.5% vs 3.0%, adjusted HR = 7.52, p = 0.004).
Interpretation
This work represents a step forward in utilizing computational flow simulation techniques in studying intracranial atherosclerotic disease. It reveals a hemodynamic pattern of sICAS that is more prone to stroke relapse, and supports hypoperfusion and artery‐to‐artery embolism as common mechanisms of ischemic stroke in such patients. Ann Neurol 2019;85:752–764
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
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