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Disclosing of Thousand Years' Mystery-- Origin of the Book of Changes 被引量:2
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作者 Jinzhong Yan 《Journal of Physical Science and Application》 2017年第1期8-20,共13页
The Book of Changes is a huge system, including (1) Taiji Yin-yang five elements system; (2) Taiji-2 status-4 images-8 hexagrams--64 hexagrams, internal 8 hexagrams and external 8 hexagrams; (3) moral system, "... The Book of Changes is a huge system, including (1) Taiji Yin-yang five elements system; (2) Taiji-2 status-4 images-8 hexagrams--64 hexagrams, internal 8 hexagrams and external 8 hexagrams; (3) moral system, "Tao generates one, one generates two, two generate three and three generate everything"; (4) heavenly stems and earthly branches system; (5) Hetu, Luoshu and 9 grid pattern systems; (6) 60 Jiazi system (a cycle of 60 years) of year, month, day and hour; (7) TCM five evolutive phases and six climatic factors system, including host evolutive phase and host climatic factor, guest evolutive phase and guest climatic factor. The Book of Changes is stemmed fi'om accurate recognition and description on life system and movement, e.g. it can (1) describe the structure, movements and changes of life core system--five abdominal Zang organs and five abdominal Fu organs with Yin-yang four-season five elements, 10 heavenly stems, Hetu, internal 8 hexagrams and host evolutive phase of five evolutive phases; (2) describe the structure, movements and changes of outside system of life form with Yin-yang six climatic factors five elements, 12 earthly branches, Luoshu, external 8 hexagrams, host climatic factor of six climatic factors; (3) describe the system of life form core structure combined with outside system with 12 energy channels system and 64 hexagrams system; (4) describe the four gradations in life form with Taiji-2 status-4 images-8 hexagrams system and moral system; (5) describe the power system of development and growth--longitudinal four seasons of life form via 60 Jiazi system (a cycle of 60 years) of year, month, day and hour; (6) the horizontal four-season movements of life form generate TCM host evolutive phase and host climatic factor, whilst the longitudinal four-season movements generate TCM guest evolutive phase and guest climatic factor. With the disclosing of origin of The Book of Changes, the universe secretes are being fully discovered. 展开更多
关键词 the book of changes ORIGIN LIFE SYSTEM movement.
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Analysis of Imaging Characteristics and Dynamic Changes of 3 Cases of Severe Novel Coronavirus Pneumonia in Qinghai Province
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作者 Yingfang Yu Ruiyun Zhao +3 位作者 Changde Li Fuqiang Ma Lingyun Guo Yang Li 《Journal of Clinical and Nursing Research》 2024年第3期120-126,共7页
Objective:To analyze the characteristics,dynamic changes,and outcomes of the first imaging manifestations of 3 patients with severe COVID-19 in our hospital.Methods:Computed tomography(CT)findings of 3 patients with s... Objective:To analyze the characteristics,dynamic changes,and outcomes of the first imaging manifestations of 3 patients with severe COVID-19 in our hospital.Methods:Computed tomography(CT)findings of 3 patients with severe COVID-19 who tested positive by the nucleic acid test in our hospital were selected,mainly focusing on the morphology,distribution characteristics,and dynamic changes of the first CT findings.Results:3 patients with severe pneumonia were older,with one aged 80.The first chest CT examination for all 3 patients differed.Imaging showed a leafy distribution of consolidation,primarily affecting the lower lobes of both lungs and extending subpleurally.A grid-like pattern was observed,along with changes in the consolidation and air bronchogram.These changes had slower absorption,especially in patients with underlying diseases.Conclusion:CT manifestations of severe COVID-19 have specific characteristics and the analysis of their characteristics and dynamic changes provide valuable insights for clinical treatment. 展开更多
关键词 COVID-19 IMAGING CT findings Dynamic changes
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Analysis of New Senior English for China Student’s Book 1
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作者 Xia Qian 《语言与文化研究》 2024年第4期128-132,共5页
This article will firstly discuss the context overview of English teaching and learning in China. Under thiscircumstance, a problematic element will be examined of the New Senior English for China Student’s Book 1 an... This article will firstly discuss the context overview of English teaching and learning in China. Under thiscircumstance, a problematic element will be examined of the New Senior English for China Student’s Book 1 and critical appraisal ofhow this element relates to other elements of curriculum development will be analyzed. The recommended changes and demonstrationmechanisms for evaluating the changes are put forward in the last two parts. 展开更多
关键词 New Senior English for China Student’s book 1 Assessment Critical appraisal Curriculum development changes
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Responses of Alpine Wetlands to Climate Changes on the Qinghai-Tibetan Plateau Based on Remote Sensing 被引量:3
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作者 WANG Rui HE Min NIU Zhenguo 《Chinese Geographical Science》 SCIE CSCD 2020年第2期189-201,共13页
The alpine wetlands in QTP(Qinghai-Tibetan Plateau)have been profoundly impacted along with global climate changes.We employ satellite datasets and climate data to explore the relationships between alpine wetlands and... The alpine wetlands in QTP(Qinghai-Tibetan Plateau)have been profoundly impacted along with global climate changes.We employ satellite datasets and climate data to explore the relationships between alpine wetlands and climate changes based on remote sensing data.Results show that:1)the wetland NDVI(Normalized Difference Vegetation Index)and GPP(Gross Primary Production)were more sensitive to air temperature than to precipitation rate.The wetland ET(evapotranspiration)across alpine wetlands was greatly correlated with precipitation rate.2)Alpine wetlands responses to climate changes varied spatially and temporally due to different geographic environments,variety of wetland formation and human disturbances.3)The vegetation responses of the Zoige wetland was the most noticeable and related to the temperature,while the GPP and NDVI of the Qiangtang Plateau and Gyaring-Ngoring Lake were significantly correlated with both temperature and precipitation.4)ET in the Zoige wetland showed a significantly positive trend,while ET in Maidika wetland and the Qiangtang plateau showed a negative trend,implying wetland degradation in those two wetland regions.The complexities of the impacts of climate changes on alpine wetlands indicate the necessity of further study to understand and conserve alpine wetland ecosystems. 展开更多
关键词 Qinghai-Tibetan Plateau(QTP) ALPINE WETLANDS climate change Moderate-resolution Imaging Spectroradiometer(MODIS) remote sensing
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Changes in the Shoreline Position Caused by Natural Processes for Coastline of Marsa Alam – Hamata, Red Sea, Egypt 被引量:3
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作者 Khalid Dewidar 《International Journal of Geosciences》 2011年第4期523-529,共7页
The probability of storms and ice-drift events and their impact on coasts is expected to increase as result of climate change. Multi-years shoreline mapping is considered a valuable task for coastal monitoring and ass... The probability of storms and ice-drift events and their impact on coasts is expected to increase as result of climate change. Multi-years shoreline mapping is considered a valuable task for coastal monitoring and assessment. This paper presents shoreline maps illustrating the shoreline erosion accretion pattern in the coastal area between Marsa Alam – Hamata of Red Sea coastline by using different sources of remote sensing data. In the present study, Landsat MSS (1972), Landsat TM (1990), Landsat ETM+ (1998, 2000) and Terra Aster (2007) satellite images were used. In this study, two techniques were used to estimate rate of shoreline retreat. The first technique is corresponding to the formation of automated shoreline positions and the second one is for estimating rate of shoreline change based on data of remote sensing applying Digital Shoreline Analysis System (DSAS) software. In this study, the End Point Rate (EPR) was calculated by dividing the distance of shoreline movement by the time elapsed between the earliest and latest measurements at each transect. Alongshore rate changes shows that there are changes of erosion and accretion pattern due to coastal processes and climate changes. 展开更多
关键词 SHORELINE changes Red Sea Satellite images Climate changes COASTAL Processes
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Monitoring of coastline changes along the Red Sea,Yemen based on remote sensing technique 被引量:7
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作者 Aref A.Sagheer Ahmed Humade Aref M.O.Al-Jabali 《Global Geology》 2011年第4期241-248,共8页
The coastline changes along Yemen's the Red Sea (Al-muka, Al-khohah, Al-tiaf, Ras Katib and Al- Urji spits) were studied using a series of landsat images (MSS, TM and ETM + , 1972, 1989, 2000, 2006), coupled wit... The coastline changes along Yemen's the Red Sea (Al-muka, Al-khohah, Al-tiaf, Ras Katib and Al- Urji spits) were studied using a series of landsat images (MSS, TM and ETM + , 1972, 1989, 2000, 2006), coupled with geomorphological, sedimentological and meteorological findings. Comparison of satellite images provided a viable means for establishing long-term coastal changes (accretion and erosion) as observed in the studied spits (Al-Urj, Ras Sham, Ras Maemoon, Ras Katib, Al-Mandar, Nukhaylah, Mujamilah, Ras Ashab Abu-Zahr and Mukha). The rate of the spit accretion has the greatest value up to 89 pixel/year corresponding to 72 290 m2/year in Mukha, while the spit erosion shows greatest value up to 131 pixel/year corresponding to 106 404 m2/year in Mujamilab. The patterns of accretion and erosion along the spits depend on the spit direction, natural processes mainly of wave-induced longshore currents, the sediments supply and depth of sea. 展开更多
关键词 coastline change landsat images Yemen Red Sea
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Spatial assessment of forest cover and land-use changes in the Hindu-Kush mountain ranges of northern Pakistan 被引量:5
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作者 Sami ULLAH Muhammad FAROOQ +3 位作者 Muhammad SHAFIQUE Muhammad Afra SIYAB Fazli KAREEM Matthias DEES 《Journal of Mountain Science》 SCIE CSCD 2016年第7期1229-1237,共9页
Anthropogenic activities and natural processes are continuously altering the mountainous environment through deforestation, forest degradation and other land-use changes. It is highly important to assess, monitor and ... Anthropogenic activities and natural processes are continuously altering the mountainous environment through deforestation, forest degradation and other land-use changes. It is highly important to assess, monitor and forecast forest cover and other land-use changes for the protection and conservation of mountainous environment. The present study deals with the assessment of forest cover and other land-use changes in the mountain ranges of Dir Kohistan in northern Pakistan, using high resolution multi-temporal SPOT-5 satellite images. The SPOT-5 satellite images of years 2004, 2007, 2010 and 2013 were acquired and classified into land-cover units. In addition, forest cover and land-use change detection map was developed using the classified maps of 2004 and 2013. The classified maps were verified through random field samples and Google Earth imagery(Quick birds and SPOT-5). The results showed that during the period 2004 to 2013 the area of forest land decreased by 6.4%, however, area of range land and agriculture land have increased by 22.1% and 2.9%, respectively. Similarly, barren land increased by 1.1%, whereas, area of snow cover/glacier is significantly decreased by 21.3%. The findings from the study will be useful for forestry and landscape planning and can be utilized by the local, provincial and national forest departments; and REDD+ policy makers in Pakistan. 展开更多
关键词 Forest cover changes Land use changes Remote sensing Hindu-Kush Mountain regions SPOT satellite images
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An Investigation of the Dimensional Changes of Polymer Mixture Tablets Containing a Soluble Drug, Using an Image Analysis Method. Influence of These Characteristics on Drug Release and Its Mechanism 被引量:1
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作者 Manuel Efentakis Despina Tavoulari 《Journal of Biomaterials and Nanobiotechnology》 2012年第2期200-207,共8页
The properties and characteristics of the polymer used for the preparation of matrix drug delivery systems considerably influence their performance and the extent of drug release and its mechanism. The objective of th... The properties and characteristics of the polymer used for the preparation of matrix drug delivery systems considerably influence their performance and the extent of drug release and its mechanism. The objective of this research was to examine the dimensional changes, and gel evolution of polymer matrices consisting of three different polymers Polyox, sodium alginate (hydrophilic) and Ethocel (hydrophobic), using an image analysis method. Furthermore to explore how these changes influence the release rate of a soluble drug namely, venlafaxine. All tablets displayed marked dimensional expansion and gel growth particularly those consisting of two hydrophilic polymers Polyox/sodium alginate (POL/SA/V) compared to those consisting of the hydrophilic/hydrophobic Polyox/Ethocel (POL/ET/V). Similarly the thickness of the gel layer in POL/SA/V matrices increased considerably with time up to 8 hours. In general our findings show that the POL/SA/V matrices, due to their thicker gel layer produced a more effective barrier which results in a more pronounced sustained release delivery. This accounts for the slower and smaller overall drug release observed with the POL/SA/V matrices compared to those containing POL/ET/V and indicates that the formation of a thick and durable gel barrier is a characteristic necessary for the preparation of sustained drug release systems. Moreover the solubility of venlafaxine in combination with the polymer’s properties appears to play an important role on the extent of drug release and the release mechanism. Overall the polymer mixtures examined comprise a useful and promising combination of materials for the development and manufacture of sustained release preparations based on these polymers. 展开更多
关键词 Polymer MIXTURE DRUG Release Image Analysis DIMENSIONAL changes
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Study of Forest Cover Change Dynamics between 2000 and 2015 in the Ikongo District of Madagascar Using Multi-Temporal Landsat Satellite Images 被引量:1
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作者 Aimé Richard Hajalalaina Arisetra Razafinimaro Nicolas Ratolotriniaina 《Advances in Remote Sensing》 2021年第3期78-91,共14页
Satellite images are considered reliable data that preserve land cover information. In the field of remote sensing, these images allow relevant analyses of changes in space over time through the use of computer tools.... Satellite images are considered reliable data that preserve land cover information. In the field of remote sensing, these images allow relevant analyses of changes in space over time through the use of computer tools. In this study, we have applied the “discriminant” change detection algorithm. In this, we have verified its effectiveness in multi-temporal studies. Also, we have determined the change in forest dynamics in the Ikongo district of Madagascar between 2000 and 2015. During the treatments, we have used the Landsat TM satellite images for the years 2000, 2005 and 2010 as well as ETM+ for 2015. Thus, analyses carried out have allowed us to note that between 2000-2005, 1.4% of natural forest disappeared. And, between 2005-2010, forests degradation<span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">was 1.8%. Also, between 2010-2015, about 0.5% of the natural forest conserved in 2010 disappeared. Furthermore, we have found that the discriminant algorithm is considerably efficient in terms of monitoring the dynamics of forest cover change.</span></span></span> 展开更多
关键词 Remote Sensing Image Processing Change Detect MULTI-TEMPORAL LANDSAT Forest Covert
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Age-related changes of lateral ventricular width and periventricular white matter in the human brain: a diffusion tensor imaging study 被引量:1
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作者 Yong Hyun Kwon Sung Ho Jang Sang Seok Yeo 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第9期986-989,共4页
Introduction Aging is the accumulation of multidimensional deterioration of process- ing of biological, psychological, and social changes with expansion over time (Bowen and Atwood, 2004; Grady, 2012). Aging-related... Introduction Aging is the accumulation of multidimensional deterioration of process- ing of biological, psychological, and social changes with expansion over time (Bowen and Atwood, 2004; Grady, 2012). Aging-related changes are typically accompanied by decline in cognitive function, urinary control, sensory-motor function, and gait ability (Bradley et al., 1991; Bowen and Atwood, 2004; Hedden and Gabrieli, 2004; Grady, 2012; Moran et al., 2012). In addition, a number of studies have suggested changes in brain structure with normal aging, such as decrease in cortical thickness or increase in ventricular width (Blatter et al., 1995; Tang et al., 1997; Uylings and de Brabander, 2002; Preul et al., 2006; Apostolova et al., 2012). In particular, ventricular enlargement has been suggested as a structural biomarker for normal aging and progression of some illnesses, such as Alzheimer's disease (Blatter et al., 1995; Tang et al., 展开更多
关键词 Age-related changes of lateral ventricular width and periventricular white matter in the human brain a diffusion tensor imaging study
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Dynamic Changes of the CT Perfusion Parameters in the Embolic Model of Cerebral Ischemia
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作者 陈唯唯 漆剑频 +2 位作者 张进华 黄文华 宋金梅 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2004年第6期615-617,共3页
Summary: To study the dynamic changes of CT perfusion parameters during the first 12 h in the embolic cerebral ischemia models. Local cerebral ischemia model were established in 7 New Zealand white rabbits. All CT sca... Summary: To study the dynamic changes of CT perfusion parameters during the first 12 h in the embolic cerebral ischemia models. Local cerebral ischemia model were established in 7 New Zealand white rabbits. All CT scans were performed with a GE Lightspeed 16 multislice CT. Following the baseline scan, further CT perfusion scans were performed at the same locations 20 min, 1-6 h and 8, 10 and 12 h after the embolus delivery. Maps of all parameters were obtained by CT perfusion software at each time point. The brains, taken 12 h after the scan, were sliced corresponding to the positions of the CT slices and stained by 2,3,5-triphenyltetrazolium chloride (TTC). On the basis of the TTC results, the ischemic sides were divided into 3 regions: core, penumbra and the relatively normal region. The changes of all parameters were then divided into 3 stages. In the first two hours (the first stage), the CBV dropped more remarkably in the core than in the penumbra but rose slightly in the relatively normal region while the CBF decreased and MTT, TTP extended in all regions to varying degrees. In the 2nd-5th h (the second stage), all the parameters fluctuated slightly around a certain level. In the 5th-12th h (the third stage), the CBV and CBF dropped, and MTT and TTP were prolonged or shortened slightly in the core and penumbra though much notably in the former while the CBV, CBF rose and MTT, TTP were shortened remarkably in the relatively normal region. We experimentally demonstrated that the location and extent of cerebral ischemia could be accurately assessed by CT perfusion imaging. The pathophysiology of the ischemia could be reflected by the CT perfusion to varying degrees. 展开更多
关键词 acute stroke CT perfusion imaging dynamic changes
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Thermoacoustic assessment of hematocrit changes in human forearms
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作者 Xue Wang Rui Zhao +5 位作者 Yi-Tong Peng Zi-Hui Chi Zhu Zheng En Li Lin Huang Hua-Bei Jian 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第9期284-289,共6页
Abnormal hematocrit(Hct)is associated with an increased risk of pre-hypertension and all-cause death in general population,and people with a high Hct value are susceptible to arterial cardiovascular disease and venous... Abnormal hematocrit(Hct)is associated with an increased risk of pre-hypertension and all-cause death in general population,and people with a high Hct value are susceptible to arterial cardiovascular disease and venous thromboembolism.In this study,we report for the first time on the ability of thermoacoustic imaging(TAI)for in vivo evaluating Hct changes in human forearms.In vitro blood samples with different Hct values from healthy volunteers(n=3)were prepared after centrifugation.TAI was performed using these samples in comparison with the direct measurements of conductivity.In vivo TAI was conducted in the forearm of healthy volunteers(n=7)where Hct changes were produced through a vascular occlusion stimulation over a period of time.The results of in vitro blood samples obtained from the 3 healthy subjects show that the thermoacoustic(TA)signals changes due to the variation of blood conductivity are closely related to the changes in Hct.In addition,the in vivo TA signals obtained from the 7 healthy subjects consistently increase in the artery/muscle and decrease in the vein during venous or arterial occlusion because of the changed Hct value in their forearms.These findings suggest that TAI has the potential to become a new tool for monitoring Hct changes for a variety of pre-clinical and clinical applications. 展开更多
关键词 thermoacoustic imaging hematocrit change human forearm
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Geographic Object-Based Image Analysis of Changes in Land Cover in the Coastal Zones of the Red River Delta (Vietnam)
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作者 Simona Niculescu Chi Nguyen Lam 《Journal of Environmental Protection》 2019年第3期413-430,共18页
The majority of the population and economic activity of the northern half of Vietnam is clustered in the Red River Delta and about half of the country’s rice production takes place here. There are significant problem... The majority of the population and economic activity of the northern half of Vietnam is clustered in the Red River Delta and about half of the country’s rice production takes place here. There are significant problems associated with its geographical position and the intensive exploitation of resources by an overabundant population (population density of 962 inhabitants/km2). Some thirty years after the economic liberalization and the opening of the country to international markets, agricultural land use patterns in the Red River Delta, particularly in the coastal area, have undergone many changes. Remote sensing is a particularly powerful tool in processing and providing spatial information for monitoring land use changes. The main methodological objective is to find a solution to process the many heterogeneous coastal land use parameters, so as to describe it in all its complexity, specifically by making use of the latest European satellite data (Sentinel-2). This complexity is due to local variations in ecological conditions, but also to anthropogenic factors that directly and indirectly influence land use dynamics. The methodological objective was to develop a new Geographic Object-based Image Analysis (GEOBIA) approach for mapping coastal areas using Sentinel-2 data and Landsat 8. By developing a new segmentation, accuracy measure, in this study was determined that segmentation accuracies decrease with increasing segmentation scales and that the negative impact of under-segmentation errors significantly increases at a large scale. An Estimation of Scale Parameter (ESP) tool was then used to determine the optimal segmentation parameter values. A popular machine learning algorithms (Random Forests-RFs) is used. For all classifications algorithm, an increase in overall accuracy was observed with the full synergistic combination of available data sets. 展开更多
关键词 COASTAL ZONES Red River Delta Land COVER changes Remote Sensing GEOGRAPHIC Object-Based images Analysis
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Spectral Features for the Detection of Land Cover Changes
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作者 Ram C. Sharma Hoan Thanh Nguyen +3 位作者 Saeid Gharechelou Xiulian Bai Luong Viet Nguyen Ryutaro Tateishi 《Journal of Geoscience and Environment Protection》 2019年第5期81-93,共13页
Derivation of more sensitive spectral features from the satellite data is immensely important for better retrieving land cover information and change monitoring, such as changes in snow covered area, forests, and barr... Derivation of more sensitive spectral features from the satellite data is immensely important for better retrieving land cover information and change monitoring, such as changes in snow covered area, forests, and barren lands as some examples from local to the global scale. The major objectives of this paper are to present the potential of water-resistant snow index (WSI) for the detection of snow cover changes in the Himalayas, extant two composite images, biophysical image composite (BIC) and forest cover composite (FCC) for the detection of changes in barren lands and forested areas respectively, and two newly designed composite images, water cover composite (WCC) and urban cover composite (UCC) for the detection of changes in water and urban areas respectively. This research implemented the image compositing technique for the detection and visualization of land cover changes (water, forest, barren, and urban) with respect to local administrative areas where a significant land cover change occurred from 2001 to 2016. A case study was also conducted in the Himalayan region to identify snow cover changes from 2001 to 2015 using the WSI. Analysis of the annual variation of the snow cover in the Himalayas indicated a decreasing trend of the snow cover. Consequently, the downstream areas are more likely to suffer from snow related hazards such as glacial outbursts, avalanches, landslides and floods. The changes in snow cover in the Himalayas may bring significant hydrophysical and livelihood changes in the downstream area including the Mekong Delta. Therefore, the countries sharing the Himalayan region should focus on adapting the severe impacts of snow cover changes. The image compositing approach presented in the research demonstrated promising performance for the detection and visualization of other land cover changes as well. 展开更多
关键词 Land COVER Water COVER COMPOSITE Urban COVER COMPOSITE SNOW COVER COMPOSITE BIOPHYSICAL Image COMPOSITE Forest COVER COMPOSITE HIMALAYAS MODIS Change DETECTION
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Integration of remotely sensed indices for land cover changes caused by the 2009 Victorian bushfires using Landsat TM imagery
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作者 GUO Li LI Xiao-jing +1 位作者 XU Xian-lei GE Lin-lin 《Journal of Coal Science & Engineering(China)》 2010年第4期400-407,共8页
In order to minimise the bushfires negative impacts on society, an efficient andreliable bushfire detection system was proposed to assess the devastated effects of the2009 Victorian bushfires.It is possible to utilise... In order to minimise the bushfires negative impacts on society, an efficient andreliable bushfire detection system was proposed to assess the devastated effects of the2009 Victorian bushfires.It is possible to utilise the repetitive capability of satellite remotesensing imagery to identify the location of change to the Earth's surface and integrate thedifferent remotely sensed indices.The results confirm that the procedure can offer essentialspatial information for bushfire assessment. 展开更多
关键词 the 2009 Victorian bushfires landsat TM land cover change detection image differencing post-classification comparison remotely sensed indices
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Relationship Between Land Use Changes and the Production of Dust Sources in Kermanshah Province,Iran
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作者 AHMADI-MOLAVERDI Majid JABBARI Iraj FATHNIA Amanollah 《Chinese Geographical Science》 SCIE CSCD 2021年第6期1057-1069,共13页
Recognizing land use changes(LUC)and evaluating their relationship with producing dust sources are considered effective to manage the environment.Taking Kermanshah Province,Iran as study area,dusty days from 2008 to 2... Recognizing land use changes(LUC)and evaluating their relationship with producing dust sources are considered effective to manage the environment.Taking Kermanshah Province,Iran as study area,dusty days from 2008 to 2015 were selected and dust sources were identified applying thermal-infrared dust index(TDI),hybrid single-particle lagrangian integrated trajectory(HYSPLIT),false color composite(FCC)and true color composite(TCC)of MODerate resolution Imaging Spectroradiometer(MODIS)images.Afterwards,the land use change map was produced using Landsat images in 2000 and 2015.Then,the distribution and frequency of the sources in each land-use change class and important dust production areas were specified.Eventually,two non-parametric tests including Chisquare and Kruskal-Wallis were applied to examine the relationship between LUC and dust sources.Results indicated that the distribution of dust sources was not identical in the study area,and the sources were mainly generated in the areas where land-use change had occurred.In fact,different classes of LUC have different contributions to dust production,and the highest contribution refers to the deflation in gentle slope areas and lowlands where the rangeland has been converted into agriculture land.The findings from this study are useful to manage and control dust in the identified sources. 展开更多
关键词 dust source hybrid single-particle lagrangian integrated trajectory(HYSPLIT) land use change(LUC) MODerate resolution imaging spectroradiometer(MODIS) thermal-infrared dust index(TDI) Kermanshah Province Iran Iran
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Diffusion kurtosis imaging of microstructural changes in brain tissue affected by acute ischemic stroke in different locations 被引量:27
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作者 Liu-Hong Zhu Zhong-Ping Zhang +2 位作者 Fu-Nan Wang Qi-Hua Cheng Gang Guo 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第2期272-279,共8页
The location of an acute ischemic stroke is associated with its prognosis. The widely used Gaussian model-based parameter, apparent diffusion coefficient(ADC), cannot reveal microstructural changes in different locati... The location of an acute ischemic stroke is associated with its prognosis. The widely used Gaussian model-based parameter, apparent diffusion coefficient(ADC), cannot reveal microstructural changes in different locations or the degree of infarction. This prospective observational study was reviewed and approved by the Institutional Review Board of Xiamen Second Hospital, China(approval No. 2014002).Diffusion kurtosis imaging(DKI) was used to detect 199 lesions in 156 patients with acute ischemic stroke(61 males and 95 females), mean age 63.15 ± 12.34 years. A total of 199 lesions were located in the periventricular white matter(n = 52), corpus callosum(n = 14), cerebellum(n = 29), basal ganglia and thalamus(n = 21), brainstem(n = 21) and gray-white matter junctions(n = 62). Percentage changes of apparent diffusion coefficient(ΔADC) and DKI-derived indices(fractional anisotropy [ΔFA], mean diffusivity [ΔMD], axial diffusivity [ΔD_a], radial diffusivity ΔDr, mean kurtosis [ΔMK], axial kurtosis [ΔK_a], and radial kurtosis [ΔK_r]) of each lesion were computed relative to the normal contralateral region. The results showed that(1) there was no significant difference in ΔADC, ΔMD, ΔD_a or ΔD_r among almost all locations.(2) There was significant difference in ΔMK among almost all locations(except basal ganglia and thalamus vs. brain stem; basal ganglia and thalamus vs. gray-white matter junctions; and brainstem vs. gray-white matter junctions.(3) The degree of change in diffusional kurtosis in descending order was as follows: corpus callosum > periventricular white matter > brainstem > gray-white matter junctions > basal ganglia and thalamus > cerebellum. In conclusion, DKI could reveal the differences in microstructure changes among various locations affected by acute ischemic stroke, and performed better than diffusivity among all groups. 展开更多
关键词 nerve REGENERATION APPARENT DIFFUSION coefficient DIFFUSION weighted IMAGING DIFFUSION KURTOSIS IMAGING acute ischemic stroke mean KURTOSIS microstructure changes white matter 1.5 TESLA magnetic resonance system neural REGENERATION
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In vivo imaging of structural,metabolic and functional brain changes in glaucoma 被引量:3
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作者 Anisha Kasi Muneeb A.Faiq Kevin C.Chan 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第3期446-449,共4页
Glaucoma, the world's leading cause of irreversible blindness, is a condition for which elevated intraocular pressure is currently the only modifiable risk factor. However, the disorder can continue to progress ev... Glaucoma, the world's leading cause of irreversible blindness, is a condition for which elevated intraocular pressure is currently the only modifiable risk factor. However, the disorder can continue to progress even at reduced intraocular pressure. This indicates additional key factors that contribute to the etiopathogenesis. There has been a growing amount of literature suggesting glaucoma as a neurodegenerative disease of the visual system. However, it remains debatable whether the observed pathophysiological conditions are causes or consequences. This review summarizes recent in vivo imaging studies that helped advance the understanding of early glaucoma involvements and disease progression in the brains of humans and experimental animal models. In particular, we focused on the non-invasive detection of early structural and functional brain changes before substantial clinical visual field loss in glaucoma patients; the eye-brain interactions across disease severity; the metabolic changes occurring in the brain's visual system in glaucoma; and, the widespread brain involvements beyond the visual pathway as well as the potential behavioral relevance. If the mechanisms of glaucomatous brain changes are reliably identified, novel neurotherapeutics that target parameters beyond intraocular pressure lowering can be the promise of the near future, which would lead to reduced prevalence of this irreversible but preventable disease. 展开更多
关键词 GLAUCOMA INTRAOCULAR pressure eye-brain-behavior relationship irreversible BLINDNESS magnetic resonance imaging METABOLIC BRAIN changes sensitivity disease progression
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Development of a large-scale remote sensing ecological index in arid areas and its application in the Aral Sea Basin 被引量:12
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作者 WANG Jie LIU Dongwei +2 位作者 MA Jiali CHENG Yingnan WANG Lixin 《Journal of Arid Land》 SCIE CSCD 2021年第1期40-55,共16页
The Aral Sea Basin in Central Asia is an important geographical environment unit in the center of Eurasia.It is of great significance to the ecological protection and sustainable development of Central Asia to carry o... The Aral Sea Basin in Central Asia is an important geographical environment unit in the center of Eurasia.It is of great significance to the ecological protection and sustainable development of Central Asia to carry out dynamic monitoring and effective evaluation of the eco-environmental quality of the Aral Sea Basin.In this study,the arid remote sensing ecological index(ARSEI)for large-scale arid areas was developed,which coupled the information of the greenness index,the salinity index,the humidity index,the heat index,and the land degradation index of arid areas.The ARSEI was used to monitor and evaluate the eco-environmental quality of the Aral Sea Basin from 2000 to 2019.The results show that the greenness index,the humidity index and the land degradation index had a positive impact on the quality of the ecological environment in the Aral Sea Basin,while the salinity index and the heat index exerted a negative impact on the quality of the ecological environment.The eco-environmental quality of the Aral Sea Basin demonstrated a trend of initial improvement,followed by deterioration,and finally further improvement.The spatial variation of these changes was significant.From 2000 to 2019,grassland and wasteland(saline alkali land and sandy land)in the central and western parts of the basin had the worst ecological environment quality.The areas with poor ecological environment quality are mainly distributed in rivers,wetlands,and cultivated land around lakes.During the period from 2000 to 2019,except for the surrounding areas of the Aral Sea,the ecological environment quality in other areas of the Aral Sea Basin has been improved in general.The correlation coefficients between the change in the eco-environmental quality and the heat index and between the change in the eco-environmental quality and the humidity index were–0.593 and 0.524,respectively.Climate conditions and human activities have led to different combinations of heat and humidity changes in the eco-environmental quality of the Aral Sea Basin.However,human activities had a greater impact.The ARSEI can quantitatively and intuitively reflect the scale and causes of large-scale and long-time period changes of the eco-environmental quality in arid areas;it is very suitable for the study of the eco-environmental quality in arid areas. 展开更多
关键词 eco-environmental quality arid remote sensing ecological index Moderate Resolution Imaging Spectroradiometer(MODIS) landscape changes remote sensing monitoring Central Asia
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Land Use and Land Cover Change Detection in the Saudi Arabian Desert Cities of Makkah and Al-Taif Using Satellite Data 被引量:3
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作者 Abdullah F. Alqurashi Lalit Kumar 《Advances in Remote Sensing》 2014年第3期106-119,共14页
Land use/land cover (LULC) changes have become a central issue in current global change and sustainability research. Saudi Arabia has undergone significant change in land use and land cover since the government embark... Land use/land cover (LULC) changes have become a central issue in current global change and sustainability research. Saudi Arabia has undergone significant change in land use and land cover since the government embarked on a course of intense national development 30 years ago, as a result of huge national oil revenues. This study evaluates LULC change in Makkah and Al-Taif, Saudi Arabia from 1986 to 2013 using Landsat images. Maximum likelihood and object-oriented classification were used to develop LULC maps. The change detection was executed using post-classification comparison and GIS. The results indicated that urban areas have increased over the period by approximately 174% in Makkah and 113% in Al-Taif. Analysis of vegetation cover over the study area showed a variable distribution from year to year due to changing average precipitation in this environment. Object-based classification provided slightly greater accuracy than maximum likelihood classification. Information provided by satellite remote sensing can play an important role in quantifying and understanding the relationship between population growth and LULC changes, which can assist future planning and potential environmental impacts of expanding urban areas. 展开更多
关键词 LAND Use/Cover Patterns LANDSAT IMAGERY Makkah Al-Taif Urban Growth Image Classification Change Detection
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