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Centennial Analysis of Human Activity Intensity and Associated Historical Events in Heilongjiang River Sino-Russo Watershed
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作者 SONG Chaoxue LI Xiaoling +1 位作者 HE Hongshi Michael SUNDE 《Chinese Geographical Science》 SCIE CSCD 2024年第2期280-293,共14页
Human activities in a transborder watershed are complex under the influence of domestic policies,international relations,and global events.Understanding the forces driving human activity change is important for the de... Human activities in a transborder watershed are complex under the influence of domestic policies,international relations,and global events.Understanding the forces driving human activity change is important for the development of transborder watershed.In this study,we used global historical land cover data,the hemeroby index model,and synthesized major historical events to analyze how human activity intensity changed in the Heilongjiang River(Amur River in Russia)watershed(HLRW).The results showed that there was a strong spatial heterogeneity in the variation of human activity intensity in the HLRW over the past century(1900-2016).On the Chinese side,the human activity intensity change shifted from the plain areas for agricultural reclamation to the mountainous areas for timber extraction.On the Russian side,human activity intensity changes mostly concentrated along the Trans-Siberian Railway and the Baikal-Amur Mainline.Localized variation of human activity intensity tended to respond to regional events while regionalized variation tends to reflect national policy change or broad international events.The similarities and differences between China and Russia in policies and positions in international events resulted in synchronous and asynchronous changes in human activity intensity.Meanwhile,policy shifts were often confined by the natural features of the watershed.These results reveal the historical origins and fundamental connotations of watershed development and contribute to formulating regional management policies that coordinate population,eco-nomic,social,and environmental activities. 展开更多
关键词 human activity intensity changes hemeroby index centennial scale Heilongjiang River(Amur River in Russia)watershed China RUSSIA
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Influence of Human Activity Intensity on Habitat Quality in Hainan Tropical Rainforest National Park,China
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作者 HAN Nianlong YU Miao +2 位作者 JIA Peihong ZHANG Yucheng HU Ke 《Chinese Geographical Science》 SCIE CSCD 2024年第3期519-532,共14页
Due to long-term human activity interference,the Hainan Tropical Rainforest National Park(HTRNP)of China has experienced ecological problems such as habitat fragmentation and biodiversity loss,and with the expanding s... Due to long-term human activity interference,the Hainan Tropical Rainforest National Park(HTRNP)of China has experienced ecological problems such as habitat fragmentation and biodiversity loss,and with the expanding scope and intensity of human activity impact,the regional ecological security is facing serious challenges.A scientific assessment of the interrelationship between human activity intensity and habitat quality in the HTRNP is a prerequisite for achieving effective management of ecological disturbances caused by human activities and can also provide scientific strategies for the sustainable development of the region.Based on the land use change data in 2000,2010,and 2020,the spatial and temporal variations and the relationship between habitat quality(HQ)and human activity intensity(HAI)in the HTRNP were explored using the integrated valuation of ecosystem services and trade-offs(InVEST)model.System dynamics and land use simulation models were also combined to conduct multi-scenario simulations of their relationships.The results showed that during 2000–2020,the habitat quality of the HTRNP improved,the intensity of human activities decreased each year,and there was a negative correlation between the two.Second,the system dynamic model could be well coupled with the land use simulation model by combining socio-economic and natural factors.The simulation scenarios of the coupling model showed that the harmonious development(HD)scenario is effective in curbing the increasing trend of human activity intensity and decreasing trend of habitat quality,with a weaker trade-off between the two compared with the baseline development(BD)and investment priority oriented(IPO)scenarios.To maintain the authenticity and integrity of the HTRNP,effective measures such as ecological corridor construction,ecological restoration,and the implementation of ecological compensation policies need to be strengthened. 展开更多
关键词 human activity intensity(HAI) habitat quality(HQ) bivariate spatial autocorrelation system dynamics model integrated valuation of ecosystem services and trade-offs(InVEST)model Hainan Tropical Rainforest National Park(HTRNP)of China
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Assessing the dynamics of human activity intensity and its natural and socioeconomic determinants in Qinghai-Tibet Plateau
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作者 Hanchu Liu Jie Fan +4 位作者 Kan Zhou Xin Xu Haipeng Zhang Rui Guo Shaofeng Chen 《Geography and Sustainability》 CSCD 2023年第4期294-304,共11页
Investigating the spatiotemporal variation of human activity intensity and its determinants is a crucial basis for further revealing the mechanism of human-environment interaction and optimizing the human development ... Investigating the spatiotemporal variation of human activity intensity and its determinants is a crucial basis for further revealing the mechanism of human-environment interaction and optimizing the human development mode.In this study,the human activity intensity on the Qinghai-Tibet Plateau(QTP)from 1990 to 2020 was measured based on the quantitative model of land use data and the actual regional background,and the under-lying natural and socioeconomic determinants were investigated using spatial econometric methods.The results demonstrate that(1)the human activity intensity in QTP has increased by 11.96%,and there are differences in different spatial scales;the areas with high human activity intensity are distributed in the Hehuang Valley where Xining City and its surrounding areas are located,as well as the One-River and Two-River Area where Lhasa City and surrounding areas are located.(2)Human activity intensity has significant positive spatial spillover,suggesting that local changes will cause changes in the same direction in adjacent areas.(3)The human activ-ity intensity in QTP is affected by various determinants.Concerning socioeconomic factors,the economic level has no significant impact on the human activity intensity in QTP,which differs from the general regional law.Both urbanization and traffic conditions have a significant positive effect,and the impact intensity continues to increase.Concerning natural factors,topographic relief has a significant positive effect;the impacts of temper-ature and vegetation coverage have changed from insignificant to a significant positive effect;the impacts of precipitation and river network density have not been verified;there is no linear relationship between altitude and human activity intensity in the entire QTP,while it exists in local regions.Finally,this study proposes three policy implications for the realization of a more harmonious human-environment relationship in QTP. 展开更多
关键词 Human activity intensity Spatiotemporal dynamics Natural and socioeconomic determinants Spatial econometric model Qinghai-Tibet Plateau
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Discussion of the Horizontal Intensity of Late Quaternary Fault Activity Along the Tianjingshan Fault Zone in Different Time Intervals and Fault Segments 被引量:1
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作者 Chai Chizhang,Zhang Weiqi,and Jiao DechengSeismological Bureau of Ningxia Hui Autonomous Region,Yinchuan 750001,China 《Earthquake Research in China》 1997年第3期25-32,共8页
By computing and classifying the data of gully offset obtained from field surveys along the Tianjingshan fault zone and estimating the ages of three types of gullies,the strike-slip rates along the fault zone are disc... By computing and classifying the data of gully offset obtained from field surveys along the Tianjingshan fault zone and estimating the ages of three types of gullies,the strike-slip rates along the fault zone are discussed in different time intervals and fault segments.The results suggest that the intensity of activity along the fault zone is not strong,but the differences between different time intervals and fault segments since the late Pleistocene have been obvious.The average rates range from 0.23 mm/a to 1.62 mm/a.The largest average rate is 1.40 mm/a,which occurred in the early and middle of late Pleistocene along the western segment of the fault zone.Since the late stage of the late Pleistocene,the center of faulting activity of the fault zone has shifted to the middle segment,and the average slip rates range have changed from 1.30 mm/a to 1.63 mm/a. 展开更多
关键词 Discussion of the Horizontal intensity of Late Quaternary Fault Activity Along the Tianjingshan Fault Zone in Different Time Intervals and Fault Segments Activity
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Evolution characteristics of seismic intensity in Tangshan seismic zone
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作者 王泽皋 乔子云 《Acta Seismologica Sinica(English Edition)》 CSCD 1998年第5期124-127,共4页
1TheuseddataTwocopiesofChinaEarthquakeCatalogueseditedbyProfesorGONGXUGUwereusedforthedatabefore1979;ChinaEa... 1TheuseddataTwocopiesofChinaEarthquakeCatalogueseditedbyProfesorGONGXUGUwereusedforthedatabefore1979;ChinaEarthquakeCatalogu... 展开更多
关键词 Tangshan earthquake long term activity intensity evolution
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Pressure and velocity cross-spectrum of normal modes in low-frequency acoustic vector field of shallow water and its application 被引量:2
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作者 Yun Yu Qing Ling Jiang Xu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第2期241-249,共9页
The pressure and horizontal particle velocity combined descriptions in the very low frequency acoustic field of shallow wa- ter integrated with the concept of effective depth of Pekeris wave- guide is proposed, especi... The pressure and horizontal particle velocity combined descriptions in the very low frequency acoustic field of shallow wa- ter integrated with the concept of effective depth of Pekeris wave- guide is proposed, especially the active component of the pressure and horizontal particle velocity cross-spectrum, also called ho- rizontal complex cross acoustic intensity, when only two normal modes are trapped in the waveguide. Both the approximate theo- retic analysis and the numerical results show that the sign of the horizontal complex cross acoustic intensity active component is independent of the range when vertically deployed receiving dual sensors are placed in appropriate depths, the sum of which is equal to the waveguide effective depth, so it can be used to tell whether the sound source is near the surface or underwater; while the range rate is expected to be measured by utilizing the sign distribution characteristic of the reactive component. The further robustness analysis of the depth classification algorithm shows that the existence of shear waves in semi infinite basement and the change of acoustic velocity profiles have few effects on the application of this method, and the seabed attenuation will limit the detection range, but the algorithm still has a good robustness in the valid detection range. 展开更多
关键词 low frequency acoustic vector field effective depth complex cross acoustic intensity active component target depth classificatio
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Space-division multiple access for CDMA multiuser underwater acoustic communications
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作者 Jingwei Yin Pengyu Du +1 位作者 Guang Yang Huanling Zhou 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第6期1184-1190,共7页
Time reversal mirror (TRM) can use the physical characteristics of the underwater acoustic (UWA) channel to focus on the desired user in multi-user UWA communication. The active average sound intensity (AASI) de... Time reversal mirror (TRM) can use the physical characteristics of the underwater acoustic (UWA) channel to focus on the desired user in multi-user UWA communication. The active average sound intensity (AASI) detector can estimate all azimuths of users with the same frequency band at the same time in order to achieve directional communication by vector combination. Space-division multiple access (SDMA) based on TRM combined with the AASI detector is proposed in this paper, which can make the capacity of the code division multiple access (CDMA) UWA system significantly increase. The simulation and lake test results show that the 7-user UWA multi-user system can achieve low bit error communication. 展开更多
关键词 underwater acoustic (UWA) communication space-division multiple access (SDMA) time reversal mirror (TRM) active average sound intensity (AASI) detector.
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Nutritional supplement drink reduces inflammation and postoperative depression in patients after off-pump coronary artery bypass surgery
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作者 Satoshi Matsushita Akie Shimada +4 位作者 Taira Yamamoto Kazuo Minematsu Hirotaka Inaba Kenji Kuwaki Atsushi Amano 《World Journal of Cardiology》 2021年第8期348-360,共13页
BACKGROUND Coronary artery bypass grafting is a surgical treatment for ischemic heart disease.Although development in surgical technique and improvement of perioperative management reduced the postoperative complicati... BACKGROUND Coronary artery bypass grafting is a surgical treatment for ischemic heart disease.Although development in surgical technique and improvement of perioperative management reduced the postoperative complications,some patients still delayed in progress of postoperative rehabilitation.In this study,we aimed to investigate the effect of daily intake of an herbal medicine-containing drink for rehabilitation after surgery in patients with ischemic heart disease.AIM To investigate the effect of taking an herbal medicine-containing,commercially available drink for postoperative rehabilitation in those patients.METHODS Patients who underwent isolated off-pump coronary artery bypass(OPCAB)surgery were divided into two groups depend on the timing of the admission to the hospital:the Yunker(YKR)group,that consumed one bottle of a caffeine-free nutritional supplement drink on a daily basis and the control group(CTL)that underwent regular rehabilitation.RESULTS A total of 229 patients(CTL=130,YKR=99)were enrolled.No significant differences were observed in the baseline characteristics between the two groups.The YKR group had a significantly increased number of daily steps postoperatively(P<0.05)and had significantly lower postoperative serum tumor necrosis factor-alpha levels(P<0.01),while no significant differences were observed in the levels of other inflammatory or stress-related cytokines(interleukin-6,adiponectin,superoxide dismutase,and urine 8-hydroxy-2′-deoxyguanosine)between the two groups.Also,the YKR group showed a significant improvement in the Hospital Anxiety and Depression Score(P<0.05).Moreover,there were no differences in postoperative complications and the duration of postoperative hospital stay between the two groups.CONCLUSION Our results demonstrated that the daily intake of an herbal medicine-containing drink after OPCAB surgery may have beneficial effects on cardiac rehabilitation by reducing inflammation markers and depression. 展开更多
关键词 Herbal medicine INFLAMMATION Cardiac rehabilitation Moderate-to-vigorous intensity physical activity Off-pump coronary artery bypass
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Identifying the spatio-temporal variability of human activity intensity and associated drivers: a case study on the Tibetan Plateau
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作者 Cai LIU Haiyan ZHANG +4 位作者 Fuping GAN Yunge LU Hao WANG Jiahong ZHANG Xing JU 《Frontiers of Earth Science》 SCIE CSCD 2022年第3期744-756,共13页
Human activities have significantly degraded ecosystems and their associated services.By understanding the spatio-temporal variability and drivers of human activity intensity(HAI),we can better evaluate the interactio... Human activities have significantly degraded ecosystems and their associated services.By understanding the spatio-temporal variability and drivers of human activity intensity(HAI),we can better evaluate the interactions between human and terrestrial ecosystems,which is essential for land-use related decision making and eco-environmental construction.As the“third pole,”the Tibetan Plateau(TP)plays a strong role in shaping the global environment,and acts as an important ecological security barrier for China.Based on land-use/cover change data,environmental geographic data,and socioeconomic data,we adopted a method for converting different land use/cover types into construction land equivalent to calculate the HAI value and applied the Getis-Ord Gi*statistic to analyze the spatio-temporal dynamics associated with HAI since 1980 on the TP.Thereafter,we explored the forces driving the HAI changes using GeoDetector software and a correlation analysis.The main conclusions are as follows:It was observed that HAI increased slowly from 3.52%to 3.65%during the 1980-2020 period,with notable increases in the western part of the Qaidam Basin and Hehuang Valley.Spatially,HAI was associated with a significant agglomeration effect,which was mainly concentrated in the regions of the Yarlung Zangbo and Yellow-Huangshui rivers.Both natural and anthropogenic factors were identified as important driving forces behind the spatial changes in HAI,of which soil type,gross domestic product,and population density had the greatest influence.Meanwhile,the temporal changes in HAI were largely driven by economic development.This information provides crucial guidance for territory development planning and ecological-protection policy decisions. 展开更多
关键词 Tibetan Plateau human activity intensity GeoDetector spatio-temporal variability driving factors
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GUIDING STUDENTS TO READ ACTIVELY THROUGH INTENSIVE READING 被引量:1
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作者 Chi Guangming 《Chinese Journal of Applied Linguistics》 2001年第4期36-38,24,共4页
This article reviews the background and problems in theteaching of intensive reading (IR) to the students with non-English majors and proposes some activities for improving theteaching and learning process of the IR c... This article reviews the background and problems in theteaching of intensive reading (IR) to the students with non-English majors and proposes some activities for improving theteaching and learning process of the IR classroom. It is expectedthat with some applicable and effective activities, the teachercan help students read actively and grow into effective andindependent readers. 展开更多
关键词 GUIDING STUDENTS TO READ activeLY THROUGH INTENSIVE READING
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Canopy structure:An intermediate factor regulating grassland diversity-function relationships under human disturbances
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作者 Xiaoxia Zhao Yuhao Feng +9 位作者 Kexin Xu Mengqi Cao Shuya Hu Qiuli Yang Xiaoqiang Liu Qin Ma Tianyu Hu Maggi Kelly Qinghua Guo Yanjun Su 《Fundamental Research》 CAS CSCD 2023年第2期179-187,共9页
Grasslands are one of the largest coupled human-nature terrestrial ecosystems on Earth,and severe anthropogenic-induced grassland ecosystem function declines have been reported recently.Understanding factors influenci... Grasslands are one of the largest coupled human-nature terrestrial ecosystems on Earth,and severe anthropogenic-induced grassland ecosystem function declines have been reported recently.Understanding factors influencing grassland ecosystem functions is critical for making sustainable management policies.Canopy structure is an important factor influencing plant growth through mediating within-canopy microclimate(e.g.,light,water,and wind),and it is found coordinating tightly with plant species diversity to influence forest ecosystem functions.However,the role of canopy structure in regulating grassland ecosystem functions along with plant species diversity has been rarely investigated.Here,we investigated this problem by collecting field data from 170 field plots distributed along an over 2000 km transect across the northern agro-pastoral ecotone of China.Aboveground net primary productivity(ANPP)and resilience,two indicators of grassland ecosystem functions,were measured from field data and satellite remote sensing data.Terrestrial laser scanning data were collected to measure canopy structure(represented by mean height and canopy cover).Our results showed that plant species diversity was positively correlated to canopy structural traits,and negatively correlated to human activity intensity.Canopy structure was a significant indicator for ANPP and resilience,but their correlations were inconsistent under different human activity intensity levels.Compared to plant species diversity,canopy structural traits were better indicators for grassland ecosystem functions,especially for ANPP.Through structure equation modeling analyses,we found that plant species diversity did not have a direct influence on ANPP under human disturbances.Instead,it had a strong indirect effect on ANPP by altering canopy structural traits.As to resilience,plant species diversity had both a direct positive contribution and an indirect contribution through mediating canopy cover.This study highlights that canopy structure is an important intermediate factor regulating grassland diversity-function relationships under human disturbances,which should be included in future grassland monitoring and management. 展开更多
关键词 Grassland ecosystem function Canopy structure Plant species diversity Human activity intensity Northern agro-pastoral ecotone
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陆地表层人类活动强度——概念、方法及应用(英文) 被引量:15
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作者 徐勇 徐小任 汤青 《Journal of Geographical Sciences》 SCIE CSCD 2016年第9期1349-1361,共13页
Human activity intensity is a synthesis index for describing the effects and influences of human activities on land surface. This paper presents the concept of human activity intensity of land surface and construction... Human activity intensity is a synthesis index for describing the effects and influences of human activities on land surface. This paper presents the concept of human activity intensity of land surface and construction land equivalent, builds an algorithm model for human activity intensity, and establishes a method for converting different land use/cover types into construction land equivalent as well. An application in China based on the land use data from 1984 to 2008 is also included. The results show that China's human activity intensity rose slowly before 2000, while rapidly after 2000. It experienced an increase from 7.63% in 1984 to 8.54% in 2008. It could be generally divided into five levels: Very High, High, Medium, Low, and Very Low, according to the human activity intensity at county level in 2008, which is rated by above 27%, 16%-27%, 10%-16%, 6%-10%, and below 6%. China's human activity intensity was spatially split into eastern and western parts by the line of Helan Mountains-Longmen Mountains-Jinghong. The eastern part was characterized by the levels of Very High, High, and Medium, and the levels of Low and Very Low were zonally distributed in the mountainous and hilly areas. In contrast, the western part was featured by the Low and Very Low levels, and the levels of Medium and High were scattered in Gansu Hexi Corridor, the east of Qinghai, and the northern and southern slopes of Tianshan Mountains in Xinjiang. 展开更多
关键词 human activity intensity land surface construction land equivalent land use/cover types China
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天山北坡人类活动强度与地表温度的时空关联性 被引量:3
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作者 陈泓瑾 刘琳 +5 位作者 张正勇 刘亚 田浩 康紫薇 王统霞 张雪莹 《Journal of Geographical Sciences》 SCIE CSCD 2022年第10期1935-1955,共21页
Research on the spatio-temporal correlation between the intensity of human activities and the temperature of earth surfaces is of great significance in many aspects,including fully understanding the causes and mechani... Research on the spatio-temporal correlation between the intensity of human activities and the temperature of earth surfaces is of great significance in many aspects,including fully understanding the causes and mechanisms of climate change,actively adapting to climate change,pursuing rational development,and protecting the ecological environment.Taking the north slope of Tianshan Mountains,located in the arid area of northwestern China and extremely sensitive to climate change,as the research area,this study retrieves the surface temperature of the mountain based on MODIS data,while characterizing the intensity of human activities thereby data on the night light,population distribution and land use.The evolution characteristics of human activity intensity and surface temperature in the study area from 2000 to 2018 were analyzed,and the spatio-temporal correlation between them was further explored.It is found that:(1)The average human activity intensity(0.11)in the research area has kept relatively low since this century,and the overall trend has been slowly rising in a stepwise manner(0.0024·a-1);in addition,the increase in human activity intensity has lagged behind that in construction land and population by 1-2 years.(2)The annual average surface temperature in the area is 7.18℃with a pronounced growth.The rate of change(0.02℃·a-1)is about 2.33 times that of the world.The striking boost in spring(0.068℃·a-1)contributes the most to the overall warming trend.Spatially,the surface temperature is low in the south and high in the north,due to the prominent influence of the underlying surface characteristics,such as elevation and vegetation coverage.(3)The intensity of human activity and the surface temperature are remarkably positively correlated in the human activity areas there,showing a strong distribution in the east section and a weak one in the west section.The expression of its spatial differentiation and correlation is comprehensively affected by such factors as scopes of human activities,manifestations,and land-use changes.Vegetation-related human interventions,such as agriculture and forestry planting,urban greening,and afforestation,can effectively reduce the surface warming caused by human activities.This study not only puts forward new ideas to finely portray the intensity of human activities but also offers a scientific reference for regional human-land coordination and overall development. 展开更多
关键词 human activity intensity surface temperature nighttime light data spatio-temporal correlation north slope of Tianshan Mountains
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An executive review of sludge pretreatment by sonication 被引量:6
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作者 Ngoc Tuan Le Carine Julcour-Lebigue Henri Delmas 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2015年第11期139-153,共15页
Ultrasonication(US), which creates hydro-mechanical shear forces in cavitation, is an advanced technology in sludge pretreatment. However, there are many factors affecting the efficacy of cavitation and ultrasonicat... Ultrasonication(US), which creates hydro-mechanical shear forces in cavitation, is an advanced technology in sludge pretreatment. However, there are many factors affecting the efficacy of cavitation and ultrasonication disintegration of sludge as a consequence.The objective of this work is to present an extensive review of evaluation approaches of sludge US pretreatment efficiency. Besides, optimization methodologies of related parameters,the differences of optimum values and the similarities of affecting trends on cavitation and sludge pretreatment efficiency were specifically pointed out, including ambient conditions,ultrasonic properties, and sludge characteristics. The research is a prerequisite for optimization of sludge US pretreatment efficiency in lab-scale and practical application. There is not-yet a comprehensive method to evaluate the efficiency of sludge US pretreatment, but some main parameters commonly used for this purpose are degree of sludge disintegration, proteins,particle size reduction, etc. Regarding US parameters, power input PUS, intensity IUS, and frequency FSseem to have significant effects. However, the magnitude of the effect of PUSand probe size in terms of IUShas not been clearly detailed. Investigating very low FSseems interesting but has not yet been taken into consideration. In addition, static pressure effect has been marginally studied only and investigation on the effect of pH prior to US process has been restricted. Their effects therefore should be varied separately and simultaneously with other related parameters, i.e. process conditions, ultrasonic properties, and sludge characteristics, to optimize sludge US pretreatment process. 展开更多
关键词 Ultrasonic pretreatment Waste activated sludge Sludge disintegration Acoustic frequency intensity effect Pressure effect
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Habitual sedentary time and stationary time are inversely related to aerobic fitness
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作者 Myles W.O'Brien Madeline E.Shivgulam +4 位作者 Jennifer L.Petterson Yanlin Wua Ryan J.Frayne Said Mekari Derek S.Kimmerly 《Sports Medicine and Health Science》 2022年第4期260-266,共7页
A one metabolic-equivalent-of-task increase in peak aerobic fitness(peak MET)is associated with a clinically relevant improvement in survival risk and all-cause mortality.The co-dependent impact of free-living physica... A one metabolic-equivalent-of-task increase in peak aerobic fitness(peak MET)is associated with a clinically relevant improvement in survival risk and all-cause mortality.The co-dependent impact of free-living physical behaviours on aerobic fitness are poorly understood.The purpose of this study was to investigate the impact of theoretically re-allocating time spent in physical behaviours on aerobic fitness.We hypothesized that substituting sedentary time with any physical activity(at any intensity)would be associated with a predicted improvement in aerobic fitness.Peak volume rate of oxygen uptake(VO_(2)peak)was assessed via indirect calorimetry during a progressive,maximal cycle ergometer protocol in 103 adults(52 females;[38±21]years;[25.0±3.8]kg/m^(2);VO_(2)peak:[35.4±11.5]ml⋅kg^(-1)⋅min^(-1)).Habitual sedentary time,standing time,light-(LPA),moderate-(MPA),and vigorous-physical activity(VPA)were assessed 24-h/day via thigh-worn inclinometry for up to one week(average:[6.3±0.9]days).Isotemporal substitution modelling examined the impact of replacing one physical behaviour with another.Sedentary time(β=0.8,95%CI:[-1.3,-0.2])and standing time(β=0.9,95%CI:[-1.6,-0.2])were negatively associated with VO_(2)peak,whereas VPA was positively associated with relative VO_(2)peak(β=9.2,95%CI:[0.9,17.6]).Substituting 30-min/day of VPA with any other behaviour was associated with a 2.4–3.4 higher peak MET.Higher standing time was associated with a lower aerobic fitness.As little as 10-min/day of VPA predicted a clinically relevant 0.8–1.1 peak MET increase.Theoretically,replacing any time with relatively small amounts of VPA is associated with improvements in aerobic fitness. 展开更多
关键词 Physical activity intensity Cardiorespiratory fitness Objective activity monitoring Sedentary activity Isotemporal substitution modelling
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