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Magnetic Particle Imaging for Magnetic Hyperthermia Treatment: Visualization and Quantification of the Intratumoral Distribution and temporal change of Magnetic Nanoparticles in Vivo

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Open Journal of Medical Imaging 2016年第1期6卷 1-15页

作者： Tomomi Kuboyabu Isamu Yabata Marina Aoki Natsuo Banura Kohei Nishimoto Atsushi Mimura Kenya Murase Department of Medical Physics and Engineering Division of Medical Technology and Science Faculty of Health Science Graduate School of Medicine Osaka University Osaka Japan

Purpose: Magnetic hyperthermia treatment (MHT) is a strategy for cancer therapy using the tem-perature rise of magnetic nanoparticles (MNPs) under an alternating magnetic field (AMF). Re-cently, a new imaging method called magnetic particle imaging (MPI) has been introduced. MPI allows imaging of the spatial distribution of MNPs. The purpose of this study was to investigate the feasibility of visualizing and quantifying the intratumoral distribution and temporal change of MNPs and predicting the therapeutic effect of MHT using MPI. Materials and Methods: Colon-26 cells (1 × 106 cells) were implanted into the backs of eight-week-old male BALB/c mice. When the tumor volume reached approximately 100 mm3, mice were divided into untreated (n = 10) and treated groups (n = 27). The tumors in the treated group were directly injected with MNPs (Resovist?) with iron concentrations of 500 mM (A, n = 9), 400 mM (B, n = 8), and 250 mM (C, n = 10), respectively, and MHT was performed using an AMF with a frequency of 600 kHz and a peak amplitude of 3.5 kA/m. The mice in the treated group were scanned using our MPI scanner immediately before, immediately after, 7 days, and 14 days after MHT. We drew a region of interest (ROI) on the tumor in the MPI image and calculated the average, maximum, and total MPI values and the number of pixels by taking the threshold value for extracting the contour as 40% of the maximum MPI value (pixel value) within the ROI. These parameters in the untreated group were taken as zero. We also measured the relative tumor volume growth (RTVG) defined by (V-V0)/V0, where V0 and V are the tumor volumes immediately before and after MHT, respectively. Results: The average, maximum, and total MPI values decreased up to 7 days after MHT and remained almost constant thereafter in all groups, whereas the number of pixels tended to increase with time. The RTVG values in Groups A and B were significantly lower than those in the control group 3 days or more and 5 day

关键词： Magnetic Particle Imaging Magnetic Hyperthermia Treatment Magnetic Nanoparticles Intratumoral Distribution temporal change

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Analysis of temporal changes in land cover and landscape metrics of a managed forest in the west Black Sea region of northern Turkey: 1970–2010

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Journal of Forestry Research 2018年第1期29卷 139-150页

作者： Hayati Zengin Ahmet Salih Degermenci Pete Bettinger Department of Forest Management and Planning Faculty of Forestry Duzce University Warnell School of Forestry and Natural Resources University of Georgia

Forest structure changes continuously by natural and anthropogenic effects. Because the level of goods and services provided by forest ecosystems are related to this structure, some attributes have to be controlled while they are being managed. In this paper we describe the long-term temporal changes in land area and landscape metrics related to different land uses of a managed forest in Turkey. The study was carried out for the Daday Forest Planning Unit located in the west Black Sea region of northern Turkey. The total area is 16,813 ha and besides wood production, it is managed for erosion control, public health, aesthetics, and recreation. Stand type maps that were constructed in 1970,1989, 1999, and 2010 were used in this analysis. Transition matrixes that illustrate area changes among cover types and temporal changes on some landscape metrics were obtained using Geographic Information Systems. Stands were separated into small patches, and thus the number of patches increased nearly two-fold between 1970 and 2010. The total forest edge increased and through the associated fragmentation, the amount of core forest area decreased at the landscape scale. Landscape metrics were applied to digitized versions of historical maps to assess how forest area changed. Human use of the land has changed, forest management practices have evolved, and these along with natural forest growth have contributed to interesting changes in landscape character.

关键词： Landscape metrics Land cover change temporal change Turkey

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

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Frontiers of Agricultural Science and Engineering 2015年第3期2卷 266-275页

作者： Ruixia SHEN Chunyan TIAN Zhidan LIU Yuanhui ZHANG Baoming LI Haifeng LU Na DUAN Laboratory of Environment-Enhancing Energy(E2E)and Key Laboratory of Agricultural Engineering in Structure and Environment Ministry of AgricultureCollege of Water Resources and Civil EngineeringChina Agricultural UniversityBeijing 100083China Department of Agricultural and Biological Engineering University of Illinois at Urbana-ChampaignUrbanaIL 61801USA

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

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

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Analysis of temporal changes in Botanical Composition of a Long-term Grazing Experiment in Nixinasuno, Japan

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Journal of Northeast Agricultural University(English Edition) 2004年第1期11卷 47-51页

作者： YIRu-han MASAEShiyomi SHIGEOTakahashi TADAKATSUOkubo CollegeofScienceandEngineering JinanUniversityGuangzhou510632PRC IbarakiUniversity Mito310-0851Japan NationalInstituteofLivestockandGrasslandScience Tochigi329-2747Japan NasuUniversity Tochigi329-3121Japan

In order to understand the temporal changes of botanical composition in grassland ecosystem, and to clarify the relation between these changes and environmental impacts, such as climatic factors and artificial disturbance, a grazing trail was carried out during a 21-year period from 1974 at a sown grassland of the National Grassland Research Institute, located in Nishinasuno, the central area of Japan. The data sets of biomass for each mouth(from April to November)of the 21 year period were analyzed in this paper. The botanical composition of aboveground biomass varied greatly with both season and year. The biomass ratio of improved herbage species to invaded native plants gradually decreased each year. This may have been owing to meteorological factors, such as low air-temperature in winter, dry and hot summers, grassland management(including grazing intensity and fertilizer application), and inter-specific competition between native and introduced herbage plants.

关键词： botanical composition grazing intensity grazing pasture temporal change nitrogen application

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Exploration of spatial and temporal characteristics of PM2.5 concentration in Guangzhou, China using wavelet analysis and modified land use regression model

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Geo-Spatial Information Science 2018年第4期21卷 311-321页

作者： Fenglei Fan Runping Liu School of Geography South China Normal UniversityGuangzhouChina Joint Laboratory of Plateau Surface Remote Sensing Tibet UniversityLhasaChina

This article attempts to detail time series characteristics of PM2.5 concentration in Guangzhou(China)from 1 June 2012 to 31 May 2013 based on wavelet analysis tools,and discuss its spatial distribution using geographic information system software and a modified land use regression *** this modified model,an important variable(land use data)is substituted for impervious surface area,which can be obtained conveniently from remote sensing imagery through the linear spectral mixture analysis *** surface has higher precision than land use data because of its sub-pixel *** concentration pattern and day-by-day change feature of PM2.5 in Guangzhou with a micro-perspective are discussed and *** include:(1)the highest concentration of PM2.5 occurs in October and the lowest in July,respectively;(2)average concentration of PM2.5 in winter is higher than in other seasons;and(3)there are two high concentration zones in winter and one zone in spring.

关键词： PM2.5 temporal change spatial distribution wavelet analysis land use regression(LUR)model GIS

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Vegetation changes in the agricultural-pastoral areas of northern China from 2001 to 2013

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Journal of Integrative Agriculture 2016年第5期15卷 1145-1156页

作者： SU Wei YU De-yong SUN Zhong-ping ZHAN Jun-ge LIU Xiao-xuan LUO Qian State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Beijing 100875 P.R. China State Key Laboratory of Remote Sensing Science/School of Geography Beijing Normal University Beijing 100875 P.R.China Satelfite Environment Center Ministry of Environmental Protection Beijing 100094 PR.China College of Information and Electrical Engineering China Agricultural University Beijing 100083 P.R.China

Climate change and human activity have resulted in increasing change of vegetation growth globally. Numerous studies have been conducted on extreme climate events and analyses of ecological environment evolution. However, such studies have placed little emphasis on vegetation change and spatial variation in this type of ecotone. Accordingly, this study analyzed the changes in vegetation type and growth using the 16-d composite MOD13A1 product with 1-km resolution and MOD12Q1 product with 1-km resolution. We used the mean, maximum, standard deviation normalized-difference vegetation index（NDVI） values, and the rate of change（ROC） of NDVI value to explain vegetation changes within the studied ecotone. Our results showed that significant vegetation type and growth changes have occurred in the study area. From 2001 to 2013, for example, with the exception of 2001, 2004 and 2009, a certain extent of grassland area was converted to cropland. Drought severity index（DSI） results indicate that there exists drought in 2001, 2004 and 2009. Such temporal changes in cropland and grassland area confirmed the ecological vulnerability of the ecotone. At the same time, vegetation varied spatially from west to east and from south to north. The mean, maximum and standard deviation NDVI values were all sorted in descending order based on differences in latitude and longitude, as follows： NDVI_（2013）〉NDVI_（2009）〉NDVI_（2004）〉NDVI_（2001）

关键词： vegetation growth agricultural-pastoral area MODIS land cover change temporal change spatial variation

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Hydrological variability and long-term floristic-structural modifications in different habitats of a tropical semi-deciduous forest

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Journal of Forestry Research 2022年第3期33卷 801-811页

作者： Alisson Borges Miranda Santos Vinicius Andrade Maia Cléber Rodrigo de Souza Natália de Aguiar-Campos Aurélio de Jesus Rodrigues Pais Wilder Bento da Silva Nathalle Cristine Alencar Fagundes Jean Daniel Morel Rubens Manoel dos Santos Department of Forestry Sciences Federal University of LavrasCampus UniversitárioC.P.3037LavrasBrazil Faculty of Environmental Engineering and Natural Resources Zambeze UniversityChimoioC.P.2400Mozambique Biological Sciences Universidade do Estado de Minas GeraisUnidade ItuiutabaAv.Antônio Carlos 6627Ituiutaba31270-901Brazil Department of Biology Federal University of LavrasUniversity campusC.P.3037Lavras37200-000Brazil

Shifts in hydrological regimes alter river flow rates and flood pulses, decrease environmental heterogeneity and the floristic-structural complexity of associated plant communities. We tested the hypothesis that drought events affect plant community composition and structure at a small-scale within a riparian fragment towards a reduction in floristic-structural complexity. The tree community was sampled in three habitats (wet, transitional and dry) and monitored in seven inventories carried out between 1991 and 2018. Hydrological variations were evaluated through annual rainfalls, river flow rates and water level data. The species richness and the detrended correspondence analysis axes were used to characterise the temporal modifications in floristic composition. Community structure was described in terms of biomass: accumulated, growth of survivors, mortality and recruitment. Generalised linear mixed models were fitted to evaluate the effects of time and environment in community. It was concluded that the climate has become drier in recent years due to declining precipitation that has affected flow rates and water levels. The floristic-structural complexity of the study fragment was maintained during the monitoring period. However, prolonged and extreme drought events displayed the potential to impact floristic-structural patterns.

关键词： Forest dynamics Climate changes Semi-deciduous seasonal forest temporal change Functioning communities

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temporal Variations in Carbon Stock of Pinus roxburghii Sargent Forests of Himachal Pradesh,India

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Journal of Mountain Science 2014年第4期11卷 959-966页

作者： Shipra SHAH Dharam Prakash SHARMA Nazir A.PALA Priyanka TRIPATHI Munesh KUMAR Department of Silviculture & Agroforestry College of Forestry Dr YS Parmar University of Horticulture & Forestry Nauni Solan 173230 India Departments of Forestry Faculty of Horticulture UBKV Pundibari Cooch Behar 736165 India Department of Forestry and Natural Resources H.N.B. Garhwal University Srinagar-Garhwal Uttarakhand 249161 India

The present study was conducted in Solan Forest Division of Himachal Pradesh covering an area of about 57,158 ha. The aim was to estimate and assess the temporal change in carbon stock of the Chil Working Circle, in two forest ranges of the Division, Solan and Dharampur, over the period of 1956-2011. The inventory data of the working plans of Solan Forest Division from 1956-1957, 1984-1985 and 2002-2003 were used in the present study while field data for biomass estimation was collected for the year *** results showed a declining trend in carbon stock over 1956-1984 period, however, an increasing trend over 1984-2002 was observed, which showed a further increase for the period 2002-2011. These fluctuating trends in the forest carbon stock can be related to increasing anthropogenic pressure on forests and the subsequent introduction of a ban on green felling envisaging efficient forest management, both of which affect the forest carbon pool significantly.

关键词： Carbon stock temporal change Climatechange Forest inventory

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Diversity and seasonal variation of ground and understory spiders from a tropical mountain cloud forest

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Insect Science 2020年第4期27卷 826-844页

作者： Emmanuel F.Campuzano Guillermo Ibarra-Nunez Salima Machkour-M Rabet Alejandro Moron-Rios Maria Luisa Jimenez Colegio de la Frontera Sur(ECOSUR) Unidad TapachulaTapachulaChiapasMexico ECOSUR Unidad ChetumalChetumalQuintana RooMexico ECOSUR Unidad CampecheCampecheCampecheMexico Centro de Investigaciones Biologicas del Noroeste(CIBNOR) La PazBaja California SurMexico

We made intensive samplings to study the seasonal response of spiders across different forest strata(ground and understory)in a tropical mountain cloud forest from *** sampled spiders from ten plots in six sampling events during the dry and rainy season,to analyze their abundance,structure(distribution of abundance among species),diversity and the response of the five dominant species at each *** demonstrated that seasonal patterns of spider communities differed among strata,revealing a complex spatiotemporal ***,structure,diversity of ground spiders,as well as the responses of four dominant species at this stratum,showed low seasonal *** contrast,a strong seasonal variation was observed for the understory assemblage,with lowest abundance and highest diversity in the rainy season,and different assemblage structures for each *** patterns of each assemblage seem linked to the responses of their dominant *** found high co-occurrence among most of the ground dominant species with similar habitat use and with multivoltine patterns,contrasting with low co-occurrence among most of the understory dominant species with similar habitat use and univoltine *** results showed that the spiders’assemblages of tropical mountain cloud forest(opposed to what is found in temperate and boreal forests)increase their species richness with the height,and that their responses to seasonal change differ between *** programs of these habitats should consider the spatial and temporal variations found here,as a better understanding of their ecological dynamics is required to support their sustainable management.

关键词： community structure El Triunfo Biosphere Reserve interspecific competition Mexico temporal change vertical stratification

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Seasonal variability in free-living marine nematode community structure in a sandy beach of the Taiping Bay of Qingdao,China

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Acta Oceanologica Sinica 2008年第2期27卷 102-115页

作者： LIU Haibin ZHANG Zhinan FAN Shiliang HUA Er DENG Ke College of Marine Life Science Ocean University of China Qingdao 266003 China Liaoeheng Agriculture Bureau Liaocheng 252000 China

Nematode assemblage composition, trophic structure and biodiversity were followed over an annual cycle in a sandy beach of the Taiping Bay of Qingdao, China. Nematode assemblage in the sandy beach maintained a high genus diversity （75 genera）. Mlero- laimus and Bathylaimus were the dominant genus of the nematode assemblage, accounting for 66% of the total nematode abundance. The nematodes＇ dominant trophic structure changed seasonally as a response to the seasonal changes in food quality. Epigrowth-feeder nematodes （2A） were the dominant trophic groups in the trophic structure with the highest abundance in spring because of phytoplankton bloom, while the feeding type （ 1 B） showed higher abundance in summer that was due to the increasing of sediment detritus after spring bloom. Furthermore, species diversity and evenness calculated on nematodes identified to the genus level displayed significant temporal changes, which was also reflected by the index of trophic diversity. According to the cluster analysis, the nematode community structure of the whole year was clearly separated into two periods （A and B）. Biota-Envlron- ment matching （BIOENV） results showed that seawater temperature, sediment Chl a and grain size were responsible for the nema- tode community structure variation in spring and summer period （Period A）. However, seawater/interstitial water temperature, interstitial water dissolved oxygen concentration,interstitial water salinity, and sediment Ph a a were more important in constructing the autumn and winter period （Period B） nematode community structure.

关键词： nematode assemblage composition trophic structure temporal change Taiping Bay of Qingdao

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