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The temporal changes of the concentration level of typical toxic organics in the river sediments around

Qiang Li, Xiong Xu, Yaoyao Fang, Ruiyang Xiao, Donghong Wang, Wenjue Zhong

《环境科学与工程前沿(英文)》 2018年 第12卷 第6期 doi: 10.1007/s11783-018-1054-7

摘要:

The current situation of typical organics in the sediments around Beijing was unclear.

56 kinds of typical toxic organics were detected in this article.

Historical data was compared with the data in this study.

The change of different organics in the sediments around Beijing was concluded.

关键词: Organic compounds     Endocrine disrupters     Sediments     Concentration     Temporal changes    

Temporal changes in the characteristics of algae in Dianchi Lake, Yunnan Province, China

Ruixia SHEN,Chunyan TIAN,Zhidan LIU,Yuanhui ZHANG,Baoming LI,Haifeng LU,Na DUAN

《农业科学与工程前沿(英文)》 2015年 第2卷 第3期   页码 266-275 doi: 10.15302/J-FASE-2015064

摘要: Algal blooms have become a worldwide environmental concern due to water eutrophication. Dianchi Lake in Yunnan Province, China is suffering from severe eutrophication and is listed in the Three Important Lakes Restoration Act of China. Hydrothermal liquefaction allows a promising and direct conversion of algal biomass into biocrude oil. In this study, algal samples were collected from Dianchi Lake after a separation procedure including dissolved air flotation with polyaluminum chloride and centrifugation during four months, April, June, August and October. The algal biochemical components varied over the period; lipids from 0.7% to 2.1% ash-free dry weight (afdw), protein from 20.9% to 33.4% afdw and ash from 36.6% to 45.2% dry weight. The algae in June had the highest lipid and protein concentrations, leading to a maximum biocrude oil yield of 24.3% afdw. Biodiversity analysis using pyrosequencing revealed different distributions of microbial communities, specifically in April (89.0%), June (63.7%) and August (84.0%), and in April (2.2%), June (12.0%) and August (1.0%). This study demonstrated remarkable temporal changes in the biochemical composition and biodiversity of algae harvested from Dianchi Lake and changes in biocrude oil production potential.

关键词: algal blooms     temporal change     biochemical property     biodiversity     hydrothermal liquefaction    

Changes in hourly precipitation may explain the sharp reduction of discharge in the middle reach of the

Lin LUO, Zhongjing WANG

《环境科学与工程前沿(英文)》 2013年 第7卷 第5期   页码 756-768 doi: 10.1007/s11783-013-0563-7

摘要: The Hekou-Longmen reach, together with local floods, is the main source area for coarse sedimentations into the Yellow River. When total rainfall slightly increased in the area, discharge dramatically decreased by 40%–70% after the year of 2000, and attracting extensive attention in the context of global climate change. High temporal resolution precipitation (timescales between 1 and 4 h) data from the June to September period from 270 rain gauges over the past three decades was mined in order to help explain the phenomenon. Each rainfall event was classified as light/moderate rain, large rain, heavy rain or rainstorm by the event’s rainfall amount, and further classified as low intensity rain, medium intensity rain and high intensity rain by the event’s rainfall intensity. The Mann-Kendall trend test was applied to detect the presence and significance of monotonic trends, and to find the change points in the mean and variance of the precipitation characteristics series, including the amount, intensity, frequency and duration of each rainfall category. Results show that although the total amount of precipitation has slightly increased, the average rainfall intensity has significantly decreased. The larger change happened in light/moderate rain events and low/medium intensity rain events, and the intensity changes have a great extent occurred around the threshold of Non-Runoff Rainfall regime, which was proposed for the approximate calculation of initial losses. Changes in rainfall distribution between different classes of the Runoff Rainfall regime in the 2000s could lead to 0.9 mm less runoff depth (17.3% of the total reduction) than the 1980–1999 period. The study indicates that changes in hourly precipitation may be responsible for the sharp reduction of discharge.

关键词: precipitation intensity     Mann-Kendall rank statistic     spatial and temporal distribution     climatic change    

Cellular changes in bronchoalveolar lavage fluid in hyperoxia-induced lung injury

HE Xinbiao, ZHAO Wei

《医学前沿(英文)》 2008年 第2卷 第4期   页码 370-373 doi: 10.1007/s11684-008-0071-5

摘要: It is well known that high concentration oxygen exposure is a model of acute lung injury (ALI). However, controversy exists over the mechanism. This study was designed to clarify the cellular characteristics in bronchoalveolar lavage fluid (BALF) and body weight loss of rats exposed to oxygen(> 90%). Young male Wistar rats, aged 6 weeks, were divided into three groups: (1) room air group (exposed to room air, = 22); (2) hyperoxia < 48 h group (exposed to over 90% oxygen for less than 48 h, = 18); (3) hyperoxia 66–72 h group (exposed to over 90% oxygen for 66–72 h group, = 7). Compared to the room air group, the total cell counts in the hyperoxia 66–72 h group decreased, whereas the neutrophils increased significantly. The body weights of the rats exposed to room air continued to increase. However, the body weights of oxygen-exposed rats increased slightly on the first day and weight loss was seen from the second day. All rats were noted to have bilateral pleural effusion in the hyperoxia 66–72 h group. The data suggests that (1) an increase in neutrophil count is an evident feature of hyperoxia-induced lung injury; (2) high concentration oxygen exposure can give rise to anorexia and malnutrition, which may play a role in hyperoxia-induced lung injury. Blocking neutrophil influx into lung tissue in the early phase and improving malnutrition are two effective methods to reduce hyperoxic lung injury.

Elucidate long-term changes of ozone in Shanghai based on an integrated machine learning method

《环境科学与工程前沿(英文)》 2023年 第17卷 第11期 doi: 10.1007/s11783-023-1738-5

摘要:

● A novel integrated machine learning method to analyze O3 changes is proposed.

关键词: Ozone     Integrated method     Machine learning    

From gut changes to type 2 diabetes remission after gastric bypass surgeries

null

《医学前沿(英文)》 2013年 第7卷 第2期   页码 191-200 doi: 10.1007/s11684-013-0258-2

摘要:

Increasing evidence suggests that the gut may influence the host’s metabolism and ultimately change the outcomes of type 2 diabetes mellitus (T2DM). We review the evidence on the relationship between the gut and T2DM remission after gastric bypass surgery, and discuss the potential mechanisms underlying the above relationship: gut anatomical rearrangement, microbial composition changes, altered gut cells, and gut hormone modulation. However, the exact changes and their relative importance in the metabolic improvements after gastric bypass surgery remain to be further clarified. Elucidating the precise metabolic mechanisms of T2DM resolution after bypass surgery will help to reveal the molecular mechanisms of pathogenesis, and facilitate the development of novel diagnoses and preventative interventions for this common disease.

关键词: gastric bypass     T2DM     gut    

Study on microbial protein and the mechanism of solid-state fermentation with periodical dynamic changes

FU Xiaoguo, CHEN Hongzhang, LI Hongqiang, MA Runyu

《化学科学与工程前沿(英文)》 2007年 第1卷 第2期   页码 113-117 doi: 10.1007/s11705-007-0021-9

摘要: The effect of different extraction and purification conditions on the microbial protein obtained from solid-state fermentation (SSF) and the effect of periodical dynamic changes of air on protein have been studied. The mechanism of solid-state fermentation with periodical dynamic changes of air is also discussed. Compared with static solid-state fermentation, periodical dynamic changes of air afford a higher protein mass; from 1 g of the fermentation microbe, 5.3 mg of the intracellular protein (an increase of 34.63%) and 9.09 mg of the extracellular protein (an increase of 17.8%) were obtained on the sixth day of fermentation. The filter paper activity and carboxymethyl cellulose activity (FPA and CMCase) of the extracellular protein are 1.739 μmol/s and 109.592 μmol/s, respectively, which represent increases of 60.1% and 21.2% over the corresponding values for static solid-state fermentation. The FPA and CMCase of the intracellular protein are 0.245 μmol/s and 6.392 μmol/s, respectively, which represent decreases of 22.2% and 38.7% over the corresponding values for static solid-state fermentation. The enzyme activity of the microbial extracellular protein in solid-state fermentation with periodical dynamic changes of air on the fifth day is nearly equal to that on the sixth day without periodical dynamic changes of air, so the period of fermentation can be shortened. The sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) experiments suggest that pulsating air pressure stimulation leads to a decrease in the amount of protein component with molecule mass of about 80400Da, and an increase in the amount of protein component with molecule mass of about 28520Da.

Realtime prediction of hard rock TBM advance rate using temporal convolutional network (TCN) with tunnel

Zaobao LIU; Yongchen WANG; Long LI; Xingli FANG; Junze WANG

《结构与土木工程前沿(英文)》 2022年 第16卷 第4期   页码 401-413 doi: 10.1007/s11709-022-0823-3

摘要: Real-time dynamic adjustment of the tunnel bore machine (TBM) advance rate according to the rock-machine interaction parameters is of great significance to the adaptability of TBM and its efficiency in construction. This paper proposes a real-time predictive model of TBM advance rate using the temporal convolutional network (TCN), based on TBM construction big data. The prediction model was built using an experimental database, containing 235 data sets, established from the construction data from the Jilin Water-Diversion Tunnel Project in China. The TBM operating parameters, including total thrust, cutterhead rotation, cutterhead torque and penetration rate, are selected as the input parameters of the model. The TCN model is found outperforming the recurrent neural network (RNN) and long short-term memory (LSTM) model in predicting the TBM advance rate with much smaller values of mean absolute percentage error than the latter two. The penetration rate and cutterhead torque of the current moment have significant influence on the TBM advance rate of the next moment. On the contrary, the influence of the cutterhead rotation and total thrust is moderate. The work provides a new concept of real-time prediction of the TBM performance for highly efficient tunnel construction.

关键词: hard rock tunnel     tunnel bore machine advance rate prediction     temporal convolutional networks     soft computing     construction big data    

Temporal trend of mortality from major cancers in Xuanwei, China

null

《医学前沿(英文)》 2015年 第9卷 第4期   页码 487-495 doi: 10.1007/s11684-015-0413-z

摘要:

Although a number of studies have examined the etiology of lung cancer in Xuanwei County, China, other types of cancer in this county have not been reported systematically. This study aimed to investigate the temporal trend of eight major cancers in Xuanwei County using data from three mortality surveys (1973–1975, 1990–1992, and 2004–2005). The Chinese population in 1990 was used as a standard population to calculate age-standardized mortality rates. Cancers of lung, liver, breast, brain, esophagus, leukemia, rectum, and stomach were identified as the leading cancers in this county in terms of mortality rate. During the three time periods, lung cancer remained as the most common type of cancer. The mortality rates for all other types of cancer were lower than those of the national average, but an increasing trend was observed for all the cancers, particularly from 1990–1992 to 2004–2005. The temporal trend could be partly explained by changes in risk factors, but it also may be due to the improvement in cancer diagnosis and screening. Further epidemiological studies are warranted to systematically examine the underlying reasons for the temporal trend of the major cancers in Xuanwei County.

关键词: cancer     mortality     Xuanwei     temporal trend    

Innate immune responses in RNA viral infection

Qian Xu, Yuting Tang, Gang Huang

《医学前沿(英文)》 2021年 第15卷 第3期   页码 333-346 doi: 10.1007/s11684-020-0776-7

摘要: RNA viruses cause a multitude of human diseases, including several pandemic events in the past century. Upon viral invasion, the innate immune system responds rapidly and plays a key role in activating the adaptive immune system. In the innate immune system, the interactions between pathogen-associated molecular patterns and host pattern recognition receptors activate multiple signaling pathways in immune cells and induce the production of pro-inflammatory cytokines and interferons to elicit antiviral responses. Macrophages, dendritic cells, and natural killer cells are the principal innate immune components that exert antiviral activities. In this review, the current understanding of innate immunity contributing to the restriction of RNA viral infections was briefly summarized. Besides the main role of immune cells in combating viral infection, the intercellular transfer of pathogen and host-derived materials and their epigenetic and metabolic interactions associated with innate immunity was discussed. This knowledge provides an enhanced understanding of the innate immune response to RNA viral infections in general and aids in the preparation for the existing and next emerging viral infections.

关键词: innate immune     viral infection     intercellular signaling     metabolic changes     epigenetic changes    

Spatio-temporal variations of water quality in Yuqiao Reservoir Basin, North China

Yuan XU,Ruqin XIE,Yuqiu WANG,Jian SHA

《环境科学与工程前沿(英文)》 2015年 第9卷 第4期   页码 649-664 doi: 10.1007/s11783-014-0702-9

摘要: Fuzzy comprehensive assessment and multivariate statistical techniques including cluster analysis, discriminant analysis, principal component analysis, and factor analysis were applied to analyze the water quality status of Yuqiao Reservoir Basin, North China, for assessing its spatio-temporal variations and identifying potential pollution sources. In this paper, we considered data for 14 water quality parameters collected during 1990–2004 at 7 water quality monitoring sites. The results of fuzzy comprehensive assessment revealed that water quality in Yuqiao Reservoir Basin showed a downtrend from 1990 to 2001 with fluctuation, and a slowly upward trend after 2001. The major water quality belonged to Class III and IV. Besides, hierarchical cluster analysis divided 7 monitoring sites into two groups (Group A and B), and 12 months into three periods (low-flow (LF), normal-flow (NF), and high-flow (HF) period). Temp, pH, SS, T-har, DO, NO -N and TP were identified as significant variables affecting spatial variations, and Temp, pH and NO -N were identified as significant variables affecting temporal variations by discriminant analysis. Factor analysis identified four latent pollution sources for water quality variations: nutrient pollution, organic pollution, inorganic pollution, and natural pollution. Moreover, for Group A regions, pollution inputs mainly came from domestic wastewater and industrial sewage. For Group B regions, it is more likely that water pollution resulted from the combined effects of domestic wastewater, hospital wastewater, agriculture runoff, and fishpond discharge, as well as the incoming water from upstream.

关键词: Fuzzy comprehensive assessment     multivariate statistical analysis     water quality    

The effect of texture and irrigation on the soil moisture vertical-temporal variability in an urban artificial

Xiaofeng ZHANG,Xu ZHANG,Guanghe LI

《环境科学与工程前沿(英文)》 2015年 第9卷 第2期   页码 269-278 doi: 10.1007/s11783-014-0672-y

摘要: Soil moisture variability in natural landscapes has been widely studied; however, less attention has been paid to its variability in the urban landscapes with respect to the possible influence of texture stratification and irrigation management. Therefore, a case study was carried out in the Beijing Olympic Forest Park to continuously monitor the soil in three typical profiles from 26 April to 11 November 2010. The texture stratification significantly affected the vertical distribution of moisture in the non-irrigated profile where moisture was mostly below field capacity. In the profile where irrigation was sufficient to maintain moisture above field capacity, gravity flow led to increased moisture with depth and thus eliminated the influence of texture. In the non-irrigated sites, the upper layer (above 80 cm) exhibited long-term moisture persistence with the time scale approximating the average rainfall interval. However, a coarse-textured layer weakened the influence of rainfall, and a fine-textured layer weakened the influence of evapotranspiration, both of which resulted in random noise-like moisture series in the deeper layers. At the irrigated site, frequent irrigation neutralized the influence of evapotranspiration in the upper layer (above 60 cm) and overshadowed the influence of rainfall in the deeper layer. As a result, the moisture level in the upper layer also behaved as a random noise-like series; whereas due to deep transpiration, the moisture of the deep layer had a persistence time-scale longer than a month, consistent with characteristic time-scales found for deep transpiration.

关键词: moisture vertical distribution     moisture temporal variation     texture stratification     irrigation     meteorological forcing     urban landscape    

Spatial and Temporal Distribution of PM

Xiao-hong Chen,Xiang-bo Tang

《工程管理前沿(英文)》 2016年 第3卷 第2期   页码 171-181 doi: 10.15302/J-FEM-2016017

摘要: Utilizing the initial hourly monitoring data of PM concentrations at 23 monitoring sites across the Chang-Zhu-Tan city cluster between January 2013 and February 2014 that released in Real-time Air Quality Reporting System in Hunan Province, this paper draws diagrams and analyzes the change rule of the pollutants concentration over time. In addition, this paper studies the regional distribution of PM seasonal pollution in the vicinity of the monitoring sites using ArcGIS geographic information system with the Kriging interpolation method. On this basis, this paper puts forward some effective control strategies to cope with regional PM pollution combined with the information of industry distribution and development status in the Chang-Zhu-Tan city cluster.

关键词: PM2.5     spatial and temporal distribution     ArcGIS     the chang-Zhu-Tan city cluster    

CLIMATE-CHANGE-INDUCED TEMPORAL VARIATION IN PRECIPITATION INCREASES NITROGEN LOSSES FROM INTENSIVE CROPPING

《农业科学与工程前沿(英文)》 2022年 第9卷 第3期   页码 457-464 doi: 10.15302/J-FASE-2022452

摘要:

● A simple model was used to evaluate how increasing temporal variability in precipitation influences crop yields and nitrogen losses.

关键词: crop yield     fertilizer timing     nitrogen loss     precipitation variability     toy model    

Anaerobic digestion of sludge by different pretreatments: Changes of amino acids and microbial community

《环境科学与工程前沿(英文)》 2022年 第16卷 第2期 doi: 10.1007/s11783-021-1458-7

摘要:

•Tryptophan protein, and aromatic protein I/II were the key identified proteins.

关键词: Sludge pretreatments     Dissolved organic nitrogen     Proteins     Amino acids     Structural equation model     Metagenomic sequencing analysis.    

标题 作者 时间 类型 操作

The temporal changes of the concentration level of typical toxic organics in the river sediments around

Qiang Li, Xiong Xu, Yaoyao Fang, Ruiyang Xiao, Donghong Wang, Wenjue Zhong

期刊论文

Temporal changes in the characteristics of algae in Dianchi Lake, Yunnan Province, China

Ruixia SHEN,Chunyan TIAN,Zhidan LIU,Yuanhui ZHANG,Baoming LI,Haifeng LU,Na DUAN

期刊论文

Changes in hourly precipitation may explain the sharp reduction of discharge in the middle reach of the

Lin LUO, Zhongjing WANG

期刊论文

Cellular changes in bronchoalveolar lavage fluid in hyperoxia-induced lung injury

HE Xinbiao, ZHAO Wei

期刊论文

Elucidate long-term changes of ozone in Shanghai based on an integrated machine learning method

期刊论文

From gut changes to type 2 diabetes remission after gastric bypass surgeries

null

期刊论文

Study on microbial protein and the mechanism of solid-state fermentation with periodical dynamic changes

FU Xiaoguo, CHEN Hongzhang, LI Hongqiang, MA Runyu

期刊论文

Realtime prediction of hard rock TBM advance rate using temporal convolutional network (TCN) with tunnel

Zaobao LIU; Yongchen WANG; Long LI; Xingli FANG; Junze WANG

期刊论文

Temporal trend of mortality from major cancers in Xuanwei, China

null

期刊论文

Innate immune responses in RNA viral infection

Qian Xu, Yuting Tang, Gang Huang

期刊论文

Spatio-temporal variations of water quality in Yuqiao Reservoir Basin, North China

Yuan XU,Ruqin XIE,Yuqiu WANG,Jian SHA

期刊论文

The effect of texture and irrigation on the soil moisture vertical-temporal variability in an urban artificial

Xiaofeng ZHANG,Xu ZHANG,Guanghe LI

期刊论文

Spatial and Temporal Distribution of PM

Xiao-hong Chen,Xiang-bo Tang

期刊论文

CLIMATE-CHANGE-INDUCED TEMPORAL VARIATION IN PRECIPITATION INCREASES NITROGEN LOSSES FROM INTENSIVE CROPPING

期刊论文

Anaerobic digestion of sludge by different pretreatments: Changes of amino acids and microbial community

期刊论文