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Seasonal constraint of dynamic water temperature on riverine dissolved inorganic nitrogen transport in land surface modeling
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作者 Shuang Liu Kaiheng Hu +1 位作者 Zhenghui Xie Yan Wang 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第4期35-40,共6页
水体温度变化对河流可溶性无机氮(DIN)输送有着强烈控制作用.然而,在全球尺度上河流DIN输送量对水温度变化的响应尚不清楚.因此,本文基于陆面过程模式,耦合河流水温估算和DIN传输方案,设定有,无动态水温情景,对比研究陆面模拟中水温变... 水体温度变化对河流可溶性无机氮(DIN)输送有着强烈控制作用.然而,在全球尺度上河流DIN输送量对水温度变化的响应尚不清楚.因此,本文基于陆面过程模式,耦合河流水温估算和DIN传输方案,设定有,无动态水温情景,对比研究陆面模拟中水温变化对河流DIN通量变化的影响.结果表明:在考虑水温动态变化后,在30°N和30°S之间, DIN通量年振幅减小5%–25%.在中国东部地区,水温动态变化使河流DIN通量在夏季减少1%–3%,在冬季增加1%–5%,对DIN通量具有明显的季节性约束作用,表明动态水温的表达在河流DIN输送模拟中的重要性. 展开更多
关键词 陆面模拟 河流氮输送 水温变化 季节变化 全球尺度
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Improvement and Evaluation of the Latest Version of WRF-Lake at a Deep Riverine Reservoir
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作者 Shibo GUO Dejun ZHU Yongcan CHEN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第4期682-696,共15页
The WRF-lake vertically one-dimensional(1D)water temperature model,as a submodule of the Weather Research and Forecasting(WRF)system,is being widely used to investigate water-atmosphere interactions.But previous appli... The WRF-lake vertically one-dimensional(1D)water temperature model,as a submodule of the Weather Research and Forecasting(WRF)system,is being widely used to investigate water-atmosphere interactions.But previous applications revealed that it cannot accurately simulate the water temperature in a deep riverine reservoir during a large flow rate period,and whether it can produce sufficiently accurate heat flux through the water surface of deep riverine reservoirs remains uncertain.In this study,the WRF-lake model was improved for applications in large,deep riverine reservoirs by parametric scheme optimization,and the accuracy of heat flux calculation was evaluated compared with the results of a better physically based model,the Delft3D-Flow,which was previously applied to different kinds of reservoirs successfully.The results show:(1)The latest version of WRF-lake can describe the surface water temperature to some extent but performs poorly in the large flow period.We revised WRF-lake by modifying the vertical thermal diffusivity,and then,the water temperature simulation in the large flow period was improved significantly.(2)The latest version of WRF-lake overestimates the reservoir-atmosphere heat exchange throughout the year,mainly because of underestimating the downward energy transfer in the reservoir,resulting in more heat remaining at the surface and returning to the atmosphere.The modification of vertical thermal diffusivity can improve the surface heat flux calculation significantly.(3)The longitudinal temperature variation and the temperature difference between inflow and outflow,which cannot be considered in the 1D WRF-lake,can also affect the water surface heat flux. 展开更多
关键词 Weather Research and Forecasting(WRF)system water–atmosphere interactions riverine reservoir inflow-outflow thermal diffusivity
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Static Stretching Combined with Conscious Slower Breathing May Increase Parasympathetic Activity and Reduce Stress in Adult Women
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作者 Mami Sakurai Yasushi Ikarashi +3 位作者 Masahiro Tabuchi Ailing Hu Takuji Yamaguchi Hiroyuki Kobayashi 《Health》 2024年第3期242-256,共15页
Background: Women are thought to be more susceptible to stress than men in a stressful society, and reducing stress is crucial for women to maintain their health. Static stretching (SST) is applied in various fields t... Background: Women are thought to be more susceptible to stress than men in a stressful society, and reducing stress is crucial for women to maintain their health. Static stretching (SST) is applied in various fields to not only increase muscle flexibility but also reduce stress. Additionally, conscious slower breathing (CSB) predominates parasympathetic activity, causing a relaxing effect. These results indicate that combining SST and CSB may be more useful in reducing stress. However, to the best of our knowledge, the effect of this combination remains unclear. Objective: This study aimed to elucidate the effects of the combination of SST and CSB on autonomic activity and stress in adult women. Methods: Eleven healthy Japanese adult female participants performed SST with nonconscious natural breathing for 20 min. The same participants performed SST in combination with CSB (2 s inspiratory and 4 s expiratory) for 20 min on another day. Salivary cortisol and chromogranin A levels were measured before and after stretching as stress markers of the hypothalamic-pituitary-adrenal axis and sympathetic nervous system. The coefficient of variation of the R-R interval (CVR-R) and high-frequency component (HF), which reflect parasympathetic nerve activity, and heart rate and low-frequency component (LF)/HF ratio, which reflect sympathetic nerve activity, were measured before, during, and after stretching. Results: SST decreased cortisol levels but with no significant changes in chromogranin A, heart rate, CVR-R, HF, or LF/HF ratio. The combination of SST and CSB increased CVR-R and HF levels in addition to decreasing cortisol levels but with no significant changes in chromogranin A, heart rate, or LF/HF levels. Conclusion: These results indicate that the combination of SST and CSB may increase parasympathetic activity and reduce stress. However, future randomized controlled trials with larger sample sizes should support this conclusion. 展开更多
关键词 Static Stretching Conscious Slower breathing Autonomic Activity Heart Rate Variability STRESS
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Evaluation of urea breath test as a diagnostic tool for Helicobacter pylori infection in adult dyspeptic patients
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作者 Zeinab Nabil Ahmed Said Asmaa Mohamed El-Nasser 《World Journal of Gastroenterology》 SCIE CAS 2024年第17期2302-2307,共6页
In this editorial,we discuss the article in the World Journal of Gastroenterology.The article conducts a meta-analysis of the diagnostic accuracy of the urea breath test(UBT),a non-invasive method for detecting Helico... In this editorial,we discuss the article in the World Journal of Gastroenterology.The article conducts a meta-analysis of the diagnostic accuracy of the urea breath test(UBT),a non-invasive method for detecting Helicobacter pylori(H.pylori)infection in humans.It is based on radionuclide-labeled urea.Various methods,both invasive and non-invasive,are available for diagnosing H.pylori infection,inclu-ding endoscopy with biopsy,serology for immunoglobulin titers,stool antigen analysis,and UBT.Several guidelines recommend UBTs as the primary choice for diagnosing H.pylori infection and for reexamining after eradication therapy.It is used to be the first choice non-invasive test due to their high accuracy,specificity,rapid results,and simplicity.Moreover,its performance remains unaffected by the distribution of H.pylori in the stomach,allowing a high flow of patients to be tested.Despite its widespread use,the performance characteristics of UBT have been inconsistently described and remain incompletely defined.There are two UBTs available with Food and Drug Administration approval:The 13C and 14C tests.Both tests are affordable and can provide real-time results.Physicians may prefer the 13C test because it is non-radioactive,compared to 14C which uses a radioactive isotope,especially in young children and pregnant women.Although there was heterogeneity among the studies regarding the diagnostic accuracy of both UBTs,13C-UBT consistently outperforms the 14C-UBT.This makes the 13C-UBT the preferred diagnostic approach.Furthermore,the provided findings of the meta-analysis emphasize the significance of precise considerations when choosing urea dosage,assessment timing,and measurement techniques for both the 13C-UBT and 14C-UBT,to enhance diagnostic precision. 展开更多
关键词 Helicobacter pylori Urea breath test DIAGNOSIS Diagnostic test accuracy META-ANALYSIS
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Advancements in breath-based diagnostics for pancreatic cancer:Current insights and future perspectives
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作者 Mesut Tez Eda Sahingoz Huseyin Fahri Martli 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第6期2300-2303,共4页
Recent decades have seen a concerning surge in carcinogenic diseases,with cancer cases and deaths on the rise globally.Conventional diagnostic methods are often invasive and time-consuming,highlighting the need for fa... Recent decades have seen a concerning surge in carcinogenic diseases,with cancer cases and deaths on the rise globally.Conventional diagnostic methods are often invasive and time-consuming,highlighting the need for fast,accurate,and painless alternatives.Non-invasive exhaled breath analysis emerges as a promising solution,with over 200 volatile organic compounds(VOCs)detected in exhaled air,showing potential as biomarkers for various diseases,including cancer.Despite the lack of standardized methodologies,advancements in analytical instruments have expanded detection capabilities,reaching 3500 VOCs.Studies have identified specific VOC patterns associated with different cancers,offering hope for non-invasive diagnosis.Techniques such as gas chromatography-mass spectrometry and electronic noses show promise in distinguishing between healthy individuals and cancer patients.However,further research and standardization are needed to realize the full clinical potential of breath-based diagnostics,particularly in the early detection of challenging cancers like pancreatic cancer. 展开更多
关键词 PANCREAS Volatile organic compounds Diagnosis Cancer breath
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Identification of breath volatile organic compounds to distinguish pancreatic adenocarcinoma,pancreatic cystic neoplasm,and patients without pancreatic lesions
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作者 Kasenee Tiankanon Nuttanit Pungpipattrakul +2 位作者 Thanikan Sukaram Roongruedee Chaiteerakij Rungsun Rerknimitr 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第3期894-906,共13页
BACKGROUND Volatile organic compounds(VOCs)are a promising potential biomarker that may be able to identify the presence of cancers.AIM To identify exhaled breath VOCs that distinguish pancreatic ductal adenocar-cinom... BACKGROUND Volatile organic compounds(VOCs)are a promising potential biomarker that may be able to identify the presence of cancers.AIM To identify exhaled breath VOCs that distinguish pancreatic ductal adenocar-cinoma(PDAC)from intraductal papillary mucinous neoplasm(IPMN)and healthy volunteers.METHODS We collected exhaled breath from histologically proven PDAC patients,radiological diagnosis IPMN,and healthy volunteers using the ReCIVA®device between 10/2021-11/2022.VOCs were identified by thermal desorption-gas chromatography/field-asymmetric ion mobility spectrometry and compared between groups.RESULTS A total of 156 participants(44%male,mean age 62.6±10.6)were enrolled(54 PDAC,42 IPMN,and 60 controls).Among the nine VOCs identified,two VOCs that showed differences between groups were dimethyl sulfide[0.73 vs 0.74 vs 0.94 arbitrary units(AU),respectively;P=0.008]and acetone dimers(3.95 vs 4.49 vs 5.19 AU,respectively;P<0.001).After adjusting for the imbalance parameters,PDAC showed higher dimethyl sulfide levels than the control and IPMN groups,with adjusted odds ratio(aOR)of 6.98(95%CI:1.15-42.17)and 4.56(1.03-20.20),respectively(P<0.05 both).Acetone dimer levels were also higher in PDAC compared to controls and IPMN(aOR:5.12(1.80-14.57)and aOR:3.35(1.47-7.63),respectively(P<0.05 both).Acetone dimer,but not dimethyl sulfide,performed better than CA19-9 in PDAC diagnosis(AUROC 0.910 vs 0.796).The AUROC of acetone dimer increased to 0.936 when combined with CA19-9,which was better than CA19-9 alone(P<0.05).CONCLUSION Dimethyl sulfide and acetone dimer are VOCs that potentially distinguish PDAC from IPMN and healthy participants.Additional prospective studies are required to validate these findings. 展开更多
关键词 Volatile organic compound PANCREAS ADENOCARCINOMA Pancreatic intraductal neoplasms breathing
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Urea breath test for Helicobacter pylori infection in adult dyspeptic patients: A meta-analysis of diagnostic test accuracy
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作者 Fabian Fellipe Bueno Lemos Caroline Tianeze de Castro +9 位作者 Marcel Silva Luz Gabriel Reis Rocha Gabriel Lima Correa Santos Luís Guilherme de Oliveira Silva Mariana Santos Calmon Cláudio Lima Souza Ana Carla Zarpelon-Schutz Kádima Nayara Teixeira Dulciene Maria de Magalhães Queiroz Fabrício Freire de Melo 《World Journal of Gastroenterology》 SCIE CAS 2024年第6期579-598,共20页
BACKGROUND Helicobacter pylori(H.pylori)infection has been well-established as a significant risk factor for several gastrointestinal disorders.The urea breath test(UBT)has emerged as a leading non-invasive method for... BACKGROUND Helicobacter pylori(H.pylori)infection has been well-established as a significant risk factor for several gastrointestinal disorders.The urea breath test(UBT)has emerged as a leading non-invasive method for detecting H.pylori.Despite numerous studies confirming its substantial accuracy,the reliability of UBT results is often compromised by inherent limitations.These findings underscore the need for a rigorous statistical synthesis to clarify and reconcile the diagnostic accuracy of the UBT for the diagnosis of H.pylori infection.AIM To determine and compare the diagnostic accuracy of 13C-UBT and 14C-UBT for H.pylori infection in adult patients with dyspepsia.METHODS We conducted an independent search of the PubMed/MEDLINE,EMBASE,and Cochrane Central databases until April 2022.Our search included diagnostic accuracy studies that evaluated at least one of the index tests(^(13)C-UBT or ^(14)C-UBT)against a reference standard.We used the QUADAS-2 tool to assess the methodo-logical quality of the studies.We utilized the bivariate random-effects model to calculate sensitivity,specificity,positive and negative test likelihood ratios(LR+and LR-),as well as the diagnostic odds ratio(DOR),and their 95%confidence intervals.We conducted subgroup analyses based on urea dosing,time after urea administration,and assessment technique.To investigate a possible threshold effect,we conducted Spearman correlation analysis,and we generated summary receiver operating characteristic(SROC)curves to assess heterogeneity.Finally,we visually inspected a funnel plot and used Egger’s test to evaluate publication bias.endorsing both as reliable diagnostic tools in clinical practice.CONCLUSION In summary,our study has demonstrated that ^(13)C-UBT has been found to outperform the ^(14)C-UBT,making it the preferred diagnostic approach.Additionally,our results emphasize the significance of carefully considering urea dosage,assessment timing,and measurement techniques for both tests to enhance diagnostic precision.Nevertheless,it is crucial for researchers and clinicians to evaluate the strengths and limitations of our findings before implementing them in practice. 展开更多
关键词 Helicobacter pylori Urea breath test DIAGNOSIS Diagnostic test accuracy META-ANALYSIS
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Analysis of the Effect of Psychological Nursing Combined with Breathing Exercises in Improving Lung Function in Patients with Pneumoconiosis
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作者 Jing Huang 《Occupational Diseases and Environmental Medicine》 2024年第1期35-40,共6页
Objective: To analyze the effect of psychological nursing combined with breathing exercises on lung function of patients with pneumoconiosis, and to analyze the methods. A total of 64 cases of pneumoconiosis admitted ... Objective: To analyze the effect of psychological nursing combined with breathing exercises on lung function of patients with pneumoconiosis, and to analyze the methods. A total of 64 cases of pneumoconiosis admitted from January 2020 to December 2022 were divided into the reference group and the experimental group by random numerical table. On the basis of symptomatic treatment, the control group was combined with conventional nursing measures and breathing exercises, while the experimental group was treated with psychological nursing on the basis of the control group, and the pulmonary function indexes and adverse mood of the two groups before and after nursing were compared. Results: There was no difference in SAS score, SDS score and pulmonary function indexes between the two groups before intervention (P > 0.05), and the SAS score in the experimental group was the SDS score was lower than that of the control group, and FEV1, FEV1% and FEV1/FVC were higher than those of the control group, and the P < 0.05 was lower. 展开更多
关键词 PNEUMOCONIOSIS Psychological Nursing breathing Exercises Lung Function
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Effects of relaxation breathing exercise on fatigue and cortisol level among Indonesian gynecological cancer patients undergoing chemotherapy:a pilot study
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作者 Mulhaeriah Mulhaeriah Mohammad Syafar Sangkala +1 位作者 Syahrul Syahrul Rezki Wahyuni 《Frontiers of Nursing》 2024年第2期201-208,共8页
Objective:This study aimed to determine the effect of the relaxation breathing exercise(RBE)on fatigue and cortisol levels among Indonesian women with gynecological cancer undergoing chemotherapy.Methods:This pilot st... Objective:This study aimed to determine the effect of the relaxation breathing exercise(RBE)on fatigue and cortisol levels among Indonesian women with gynecological cancer undergoing chemotherapy.Methods:This pilot study consecutively recruited 44 gynecological cancer patients to receive RBE(22)or usual care(22).Cortisol level was measured before and after completion of the intervention(day 8).Fatigue was measured using the Piper Fatigue Scale(PFS).Anxiety and depression were assessed using the Hospital Anxiety and Depression Scale(HADS)at the baseline days of the study for days 1,4,and 8.The obtained data were analyzed using Fisher’s exact test,the independent t-test,and the Mann-Whitney U test.Results:There were significant increases in cortisol levels within the groups,either the intervention or control groups,respectively(P-value=0.0003 and 0.001).Despite there being no statistical significance between the intervention and control groups,there were noticeable differences in the cortisol levels,indicating the extreme increase in cortisol levels in the control group(Median[IQR1-IQR3]:2.30[0.99-9.09];Min-Max:0.43-23.38)compared with the intervention group(Median[IQR1-IQR3]=2.97[1.26-5.18];Min-Max=0.39-6.91).Conclusions:RBE helps prevent a significant increase in cortisol levels that can alleviate fatigue for women with gynecological cancer.Further research was recommended to compare several intervention modalities for fatigue and cancer-related symptom management based on cortisol level changes. 展开更多
关键词 ANXIETY CORTISOL FATIGUE gynecological cancer relaxation breathing exercise
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The Importance of Breathing Training in Folk Dance Teaching
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作者 Xiaowei Sun 《Journal of Contemporary Educational Research》 2024年第4期187-192,共6页
The importance of breathing training in dance teaching is reflected in the two aspects of enhancing the quality of dance movements and sublimating the connotation of dance movements.For example,high-quality breathing ... The importance of breathing training in dance teaching is reflected in the two aspects of enhancing the quality of dance movements and sublimating the connotation of dance movements.For example,high-quality breathing can help performers complete the dance movements and improve the coordination of the movements;at the same time,the unique body rhythm formed by breathing can strengthen the visual effect of the performance and convey its spirit and soul to the audience.This requires folk dance teachers to carry out relevant training and teaching activities based on the categories and skills of dance breathing,such as changing students’ideological cognition,developing periodic breathing training courses,providing personalized guidance to students,and allowing students to adjust their learning and practice methods in the evaluation. 展开更多
关键词 Folk dance teaching breathing training IMPORTANCE Training methods
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Testing coral paleothermometers(B/Ca, Mg/Ca, Sr/Ca, U/Ca and δ^(18)O) under impacts of large riverine runoff 被引量:4
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作者 CHEN Tianran YU Kefu +4 位作者 ZHAO Jianxin YAN Hongqiang SONG Yinxian FENG Yuexing CHEN Tegu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第8期20-26,共7页
Sea surface temperature (SST) proxies including B/Ca, Mg/Ca, St/Ca, U/Ca and δ180 were analyzed in the skeleton of a Porites coral collected from the Zhujiang River (Pearl River) Estuary (ZRE). These geochemica... Sea surface temperature (SST) proxies including B/Ca, Mg/Ca, St/Ca, U/Ca and δ180 were analyzed in the skeleton of a Porites coral collected from the Zhujiang River (Pearl River) Estuary (ZRE). These geochemical proxies are influenced by river runoff and this area of the northern South China Sea is strongly affected by seasonal freshwater floods. We assessed the robustness of each SST proxy through comparison with the local instrumental SST. Coral St/Ca shows the highest correlation with SST variations (r2=0.59), suggesting St/Ca is the most robust SST proxy. In contrast, coral δ180 (r2=0.46), B/Ca (r2=0.43) and U/Ca (r2=0.41) ratios were only moderately correlated with SST variations, suggesting that they are disturbed by some other factors in addition to SST. The poor correlation (r2=0.27) between SST and Mg/Ca indicates that Mg/Ca in coral skeletons is not a simple function of SST variations. This may ultimately limit the use of Mg/Ca as a coral paleothermometer. 展开更多
关键词 Porites coral SST proxies coral paleothermometers riverine runoff Zhujiang River (Pearl River) Estuary northern South China Sea
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Sand source and formation mechanism of riverine sand dunes: a case study in Xiangshui River, China 被引量:1
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作者 WANG Yong YAN Ping +2 位作者 HAN Guang WU Wei ZHANG Run 《Journal of Arid Land》 SCIE CSCD 2019年第4期525-536,共12页
Riverine sand dunes develop as a result of fluvial-aeolian interactions. The primarily barchan dune chains along the Xiangshui River(a branch of the Xar Moron River in the western part of the Horqin Sandy Land of Chin... Riverine sand dunes develop as a result of fluvial-aeolian interactions. The primarily barchan dune chains along the Xiangshui River(a branch of the Xar Moron River in the western part of the Horqin Sandy Land of China) form a typical riverine dune field. We collected a series of samples from the riverine sand dunes parallel to the direction of the prevailing wind and investigated the sand sources and formation mechanisms of these dunes by determining the grain size, heavy mineral content and optically stimulated luminescence(OSL) of the samples. The sand of the near-river dunes was coarser than the sand of the dunes distant from the river, indicating that coarse sand of the valley mainly deposited on near-river dunes. The heavy mineral analysis suggested that wind-sand activity levels were intense on the upwind dunes, but relatively weak on the downwind dunes. This indicated that the sand sources for the near-river dunes were more abundant than those of the distant dunes. Our OSL analysis of samples suggested that the deposition rates on dunes near the river were greater than the deposition rates on dunes distant from the river. The development of dunes along the river indicated that the river played an important role in dune formation and development. In addition, airflow fluctuation and the formation of the waveform dunes had a type of feedback relationship. Grain size, heavy mineral and OSL analyses are widely used methods in wind-sand research. Sand dune grain size characteristics reflect the effects of airflow on the transport and separation of sand materials, as well as the physical characteristics of the sand sources. Heavy mineral characteristics are often used to investigate the relationships between sediments and sand sources. OSL indicates dune age, revealing formation of dunes. Therefore, it is useful to explore dune sand sources, as well as the mechanisms underlying dune formation, by determining grain size, heavy mineral content and OSL. This study investigated the sand sources of riverine dunes and provided new information about riverine dune formation and development. 展开更多
关键词 riverine DUNE grain size heavy MINERAL optically stimulated luminescence(OSL) Horqin SANDY Land
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Centrifugal model test on a riverine landslide in the Three Gorges Reservoir induced by rainfall and water level fluctuation 被引量:3
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作者 Fasheng Miao Yiping Wu +2 位作者 Ákos Török Linwei Li Yang Xue 《Geoscience Frontiers》 SCIE CAS CSCD 2022年第3期196-209,共14页
Frequent soil landslide events are recorded in the Three Gorges Reservoir area,China,making it necessary to investigate the failure mode of such riverside landslides.Geotechnical centrifugal test is considered to be t... Frequent soil landslide events are recorded in the Three Gorges Reservoir area,China,making it necessary to investigate the failure mode of such riverside landslides.Geotechnical centrifugal test is considered to be the most realistic laboratory model,which can reconstruct the required geo-stress.In this study,the Liangshuijing landslide in the Three Gorgers Reservoir area is selected for a scaled centrifugal model experiment,and a water pump system is employed to retain the rainfall condition.Using the techniques of digital photography and pore water pressure transducers,water level fluctuation is controlled,and multi-physical data are thus obtained,including the pore water pressure,earth pressure,surface displacement and deep displacement.The analysis results indicate that:Three stages were set in the test(waterflooding stage,rainfall stage and drainage stage).Seven transverse cracks with wide of 1–5 mm appeared during the model test,of which 3 cracks at the toe landslide were caused by reservoir water fluctuation,and the cracks at the middle and rear part were caused by rainfall.During rainfall process,the maximum displacement of landslide model reaches 3 cm.And the maximum deformation of the model exceeds 12 cm at the drainage stage.The failure process of the slope model can be divided into four stages:microcracks appearance and propagation stage,thrust-type failure stage,retrogressive failure stage,and holistic failure stage.When the thrust-type zone caused by rainfall was connected or even overlapped with the retrogressive failure zone caused by the drainage,the landslide would start,which displayed a typical composite failure pattern.The failure mode and deformation mechanism under the coupling actions of water level fluctuation and rainfall are revealed in the model test,which could appropriately guide for the analysis and evaluation of riverside landslides. 展开更多
关键词 riverine landslide The Three Gorges Reservoir Centrifugal model test RAINFALL Fluctuation of water level
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RIVERINE SEDIMENTS AND CHINESE COASTLINE CHANGES
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作者 李从先 张桂甲 《Chinese Geographical Science》 SCIE CSCD 1997年第3期201-207,共7页
The tectonic uplifting and depression in the coastal zones results in the anormal distribution of riverine sediments. The coastal zones of tectonic depression areas received about 95% of the riveine sediments, whereas... The tectonic uplifting and depression in the coastal zones results in the anormal distribution of riverine sediments. The coastal zones of tectonic depression areas received about 95% of the riveine sediments, whereas the tectonic uplift belts received only 5% of that, which is the main reason for the variety of the coastline types and the changes in the coastline. On the basis of this anormal distribution of riverine sediments in Chinese coastline, this paper discusses the scope and time of the maximum transgression, the trend, rate and period of the coastline changes, and the impact of riverine sediments on the future changes in coastline. 展开更多
关键词 COASTLINE COASTAL environment riverine SEDIMENTS SEA level RISE
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Spatial Distribution of Plant-Associated Invertebrates and Environmental Bioassessment in a Natural Riverine Lake (Lake Fibreno, Central Italy)
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作者 Luciana Mastrantuono Valentina Di Vito Marcello Bazzanti 《Journal of Water Resource and Protection》 2014年第10期916-929,共14页
Lake Fibreno is a Mediterranean riverine lake located in Central Italy and fed by large flows of groundwater and characterized by the presence of a wide reed stand area and of the only floating island of the South Eur... Lake Fibreno is a Mediterranean riverine lake located in Central Italy and fed by large flows of groundwater and characterized by the presence of a wide reed stand area and of the only floating island of the South Europe. It is enclosed in a Natural Reserve recognized as Special Area of Conservation (SAC-IT6050015) for the presence of habitats and species (92/43/EEC) of relevant scientific interest. In this paper, we compare the plant-associated meio-macrobenthic invertebrates among sites with different environmental characteristics. Both vegetation and invertebrates of Lake Fibreno were well diversified and abundant and were composed of a mixing of species typical of lentic and lotic waters. Our results show that a gradient of orthophosphate and nitrite contents and current velocity appeared to be the driver factors affecting the flora and fauna spatial distribution at the sampling sites. To obtain a bioassessment of the ecological quality of the vegetation zone, we compared the riverine Lake Fibreno with typical lentic lakes previously studied in Central Italy. We selected metrics, such as macrophyte belt extent and taxa richness, invertebrate species richness and Shannon diversity, ETOM (Ephemeropta + Trichoptera + Odonata + Mollusca), ETOC (Ephemeropta + Trichoptera + Odonata + Coleoptera) and LCrM (Large Crustacea + Mollusca). The comparison indicated a good ecological status of the vegetation zone of Lake Fibreno mainly due to the continuous washout effects (dilution and fast water removal) which reduce the nutrient content available for phytoplankton and maintain the high transparency and good oxygenation of the lake waters. 展开更多
关键词 MACROPHYTES Meio- and MACROINVERTEBRATES Mediterranean riverine LAKE Ecological BIOASSESSMENT
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Wuzhen -- "the Last Riverine Town in China"
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作者 Vivian Guan 《China's Foreign Trade》 2017年第6期60-63,共4页
Wuzhen is a typical riverine town south of the Yangtze River.Due to the World Internet Conference being held there,it seems to have become a place where CEOs a nd bosses of inter net compa n ies working on plans for t... Wuzhen is a typical riverine town south of the Yangtze River.Due to the World Internet Conference being held there,it seems to have become a place where CEOs a nd bosses of inter net compa n ies working on plans for the industry’s development gather. 展开更多
关键词 In the Last riverine Town in China Wuzhen
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Fluxes of riverine nutrient to the Zhujiang River Estuary and its potential eutrophication effect
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作者 Li Zhang Yumin Yang +2 位作者 Weihong He Jie Xu Ruihuan Li 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2022年第6期88-98,共11页
The Zhujiang River Estuary is becoming eutrophic due to the impact of anthropogenic activities in the past decades.To understand nutrient dynamics and fluxes to the Lingdingyang water via four outlets(Humen,Jiaomen,Ho... The Zhujiang River Estuary is becoming eutrophic due to the impact of anthropogenic activities in the past decades.To understand nutrient dynamics and fluxes to the Lingdingyang water via four outlets(Humen,Jiaomen,Hongqimen and Hengmen),we investigated the spatial distribution and seasonal variation of dissolved nutrients in the Zhujiang River Estuary,based on fourteen cruises conducted from March 2015 to October 2017,covering both wet(April to September)and dry(October to March next year)seasons.Our results showed that riverine fluxes of dissolved inorganic nitrogen(DIN)and dissolved silicate(DSi)into the Lingdingyang water through four outlets varied seasonally due to the influence of river discharge,with the highest in spring and the lowest in winter.However,riverine flux of phosphate exhibited little significant seasonal variability.Riverine nutrients into the Lingdingyang water most resulted through Humen Outlet.The estuarine export fluxes of DIN out of the Zhujiang River Estuary derived from a box model were higher than fluxes of riverine nutrients in May,likely due to the influence of local sewage,while lower than riverine flux in August.The export fluxes of phosphate were higher than the fluxes of riverine phosphate in May and August.In contrast,large amounts of DSi were buried in the estuary in May and August.Although excess DIN was delivered into the Zhujiang River Estuary,eutrophication effect was not as severe as expected in the Zhujiang River Estuary,since the light limitation restricted the utilization of nutrients by phytoplankton. 展开更多
关键词 riverine nutrient FLUX Lingdingyang Zhujiang River Estuary EUTROPHICATION
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Prevalence and risk assessment of antibiotics in riverine estuarine waters of Larut and Sangga Besar River, Perak
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作者 Kyleyoung LOW Layching CHAI +4 位作者 Choonweng LEE Gan ZHANG Ruijie ZHANG Vaezzadeh VAHAB Chuiwei BONG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2021年第1期122-134,共13页
Antibiotics released into the environment through anthropogenic activities exert selective pressure,driving bacteria towards increasing antimicrobial resistance.The prevalence of antibiotics and the ecological risks p... Antibiotics released into the environment through anthropogenic activities exert selective pressure,driving bacteria towards increasing antimicrobial resistance.The prevalence of antibiotics and the ecological risks posed in the riverine estuarine of Larut River and Sangga Besar River,which included wastewater effl uents from hospital,zoo,and poultry slaughterhouse sources were investigated.Solid phase extraction(SPE)followed by high-performance liquid chromatography tandem mass chromatography(HPLC-MS/MS)were used to extract and quantify the antibiotic residues from 22 antibiotics belonging to six major antibiotic classes(sulfonamide,macrolide,fl uoroquinolone,phenicol,trimethoprim,and tetracycline).Sixteen antibiotic residues were detected with concentrations ranging from limit of detection(LOD)to 1262.3 ng/L.Fluoroquinolones and macrolides were the most frequently detected compounds.Erythromycin,clarithromycin,and ofl oxacin detected in hospital and zoo effl uents posed a high risk to algae while tetracycline had low to medium ecological risks toward all the relevant organisms from aquatic environments(algae,invertebrate Daphnia magna,and fi sh). 展开更多
关键词 antibiotic residues PREVALENCE ecological risk anthropogenic pollution riverine ESTUARINE
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RIVERINE INORGANIC CARBON DYNAMICS:OVERVIEW AND PERSPECTIVE
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作者 YAO Guan-rong GAO Quan-zhou 《Chinese Geographical Science》 SCIE CSCD 2006年第2期183-191,共9页
Inorganic carbon, the great part of the riverine carbon exported to the ocean, plays an important role in the global carbon cycle and ultimately impacts the coupled carbon-climate system. An overview was made on both ... Inorganic carbon, the great part of the riverine carbon exported to the ocean, plays an important role in the global carbon cycle and ultimately impacts the coupled carbon-climate system. An overview was made on both methods and results of the riverine inorganic carbon researches. In addition to routine in situ survey, measurement and calculation, the direct precipitation method and the gas evolution technique were commonly used to analyze dissolved inorganic carbon in natural water samples. Soil CO2, carbonate minerals and atmospheric CO2 incorporated into riverine inorganic carbon pool via different means, with bicarbonate ion being the dominant component. The concentration of inorganic carbon, the composition of carbon isotopes (δ13C and Δ14C), and their temporal or spatial variations in the streams were controlled by carbon input, output and changes of carbon biogeochemistry within the riverine system. More accurate flux estimation, better understanding of different influential processes, and quantitative determination of various inputs or outputs need to be well researched in future. 展开更多
关键词 河流 无机成分 溶解气体 气候变化
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Ability of lactulose breath test results to accurately identify colorectal polyps through the measurement of small intestine bacterial overgrowth 被引量:1
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作者 Lan Li Xue-Yuan Zhang +5 位作者 Jin-Sheng Yu Hui-Min Zhou Yan Qin Wen-Rui Xie Wen-Jing Ding Xing-Xiang He 《World Journal of Gastrointestinal Surgery》 SCIE 2023年第6期1138-1148,共11页
BACKGROUND While colorectal polyps are not cancerous,some types of polyps,known as adenomas,can develop into colorectal cancer over time.Polyps can often be found and removed by colonoscopy;however,this is an invasive... BACKGROUND While colorectal polyps are not cancerous,some types of polyps,known as adenomas,can develop into colorectal cancer over time.Polyps can often be found and removed by colonoscopy;however,this is an invasive and expensive test.Thus,there is a need for new methods of screening patients at high risk of developing polyps.AIM To identify a potential association between colorectal polyps and small intestine bacteria overgrowth(SIBO)or other relevant factors in a patient cohort with lactulose breath test(LBT)results.METHODS A total of 382 patients who had received an LBT were classified into polyp and non-polyp groups that were confirmed by colonoscopy and pathology.SIBO was diagnosed by measuring LBTderived hydrogen(H)and methane(M)levels according to 2017 North American Consensus recommendations.Logistic regression was used to assess the ability of LBT to predict colorectal polyps.Intestinal barrier function damage(IBFD)was determined by blood assays.RESULTS H and M levels revealed that the prevalence of SIBO was significantly higher in the polyp group than in the non-polyp group(41%vs 23%,P<0.01;71%vs 59%,P<0.05,respectively).Within 90 min of lactulose ingestion,the peak H values in the adenomatous and inflammatory/hyperplastic polyp patients were significantly higher than those in the non-polyp group(P<0.01,and P=0.03,respectively).In 227 patients with SIBO defined by combining H and M values,the rate of IBFD determined by blood lipopolysaccharide levels was significantly higher among patients with polyps than those without(15%vs 5%,P<0.05).In regression analysis with age and gender adjustment,colorectal polyps were most accurately predicted with models using M peak values or combined H and M values limited by North American Consensus recommendations for SIBO.These models had a sensitivity of≥0.67,a specificity of≥0.64,and an accuracy of≥0.66.CONCLUSION The current study made key associations among colorectal polyps,SIBO,and IBFD and demonstrated that LBT has moderate potential as an alternative noninvasive screening tool for colorectal polyps. 展开更多
关键词 Lactulose breath test Colorectal polyp Small intestine bacteria overgrowth Intestinal barrier function Retrospective study
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