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Yimin Chen,1 Thanh N Nguyen,2 James E Siegler,3 Mohammad Mofatteh,4 Jack Wellington,5 Rongshen Yang,6,7 Lihong Zeng,1 Jiale Wu,6,7 Xi Sun,6,7 Daiyu Liang,6,7 Qiubi Tang,8 Sijie Chen,6,7 Xisheng Huang,6,7 Shuiquan Yang,1 Xuxing Liao9,10 1Department of Neurology and Advanced National Stroke Center, Foshan Sanshui District People’s Hospital, Foshan, People’s Republic of China; 2Department of Neurology, Radiology, Boston University School of Medicine, Boston, MA, USA; 3Cooper Neurological Institute, Cooper University Hospital, Camden, NJ, USA; 4School of Medicine, Dentistry and Biomedical Sciences, Queen’s University Belfast, Belfast, UK; 5School of Medicine, Cardiff University, Cardiff, UK; 6Medical Intern of Neurology Department, Foshan Sanshui District People’s Hospital, Foshan, People’s Republic of China; 7School of Medicine, Shaoguan University, Shaoguan, People’s Republic of China; 8Chronic Disease Department, The Affiliated Brain Hospital of Guangzhou Medical University, Guangzhou, People’s Republic of China; 9Dean Office and Advanced National Stroke Center, Foshan Sanshui District People’s Hospital, Foshan, People’s Republic of China; 10Department of Neurosurgery, First People’s Hospital of Foshan, Foshan, People’s Republic of ChinaCorrespondence: Shuiquan Yang, Department of Neurology and Advanced National Stroke Center, Foshan Sanshui District People’s Hospital, No. 16, Guanghaidadaoxi, Sanshui District, Foshan, People’s Republic of China, Email yangshuiquan1969@126.com Xuxing Liao, Dean Office and Advanced National Stroke Center, Foshan Sanshui District People’s Hospital, Foshan, People’s Republic of China, Email drliao210409@163.comPurpose: This study aimed to investigate the impact of characteristic ischemic stroke and outcomes during the first COVID-19 pandemic lockdown.Patients and Methods: A retrospective, observational cohort study of a comprehensive tertiary stroke center was conducted. Patients with ischemic stroke were divided into pre-COVID-19 lockdown (11/1/2019 to 1/30/2020) and COVID-19 lockdown (1/31/2020 to 4/30/2020) period groups. Patient data on stroke admission, thrombolysis, endovascular treatment, and 3-month routine follow-up were recorded. Data analysis was performed using SPSS according to values following a Gaussian distribution.Results: The pre-COVID-19 lockdown period group comprised 230 patients compared to 215 patients in the COVID-19 lockdown period group. Atrial fibrillation was more predominant in the COVID-19 lockdown period group (11.68% vs 5.65%, p=0.02) alongside patients who were currently smoking (38.8% vs 28.7%, p=0.02) and drinking alcohol (30.37% vs 20.00%, p=0.012) compared with that of the pre-COVID-19 lockdown period group. For patients receiving thrombolysis, the median door-to-CT time was longer in the COVID-19 lockdown period group (17.0 min (13.0, 24.0) vs 12.0 min (8.0, 17.3), p=0.012), median door to needle time was 48.0 minutes (35.5, 73.0) vs 43.5 minutes (38.0, 53.3), p=0.50, compared with that of the pre-COVID-19 lockdown period group. There were no differences for patients receiving mechanical thrombectomy. The median length of hospitalization (IQR) was no different. Discharge mRS scores (IQR) were higher in the COVID-19 lockdown period group (1.0 (1.0, 3.0) vs 1.0 (1.0, 2.0), p=0.022). Compared with the pre-COVID-19 lockdown period, hospitalization cost (Chinese Yuan) in the COVID-19 period group was higher (13,445.7 (11,009.7, 20,030.5) vs 10,799.2 (8692.4, 16,381.7), p=0.000). There was no difference observed in 3-month mRS scores.Conclusion: Patients presenting with ischemic stroke during the COVID-19 pandemic lockdown period had longer median door-to-CT time and higher hospitalization costs. There were no significant differences in 3-month outcomes. Multidisciplinary collaboration and continuous workflow optimization may maintain stroke care during the COVID-19 pandemic lockdown.Keywords: ischemic stroke, COVID-19 pandemic, thrombolysis, thrombectomy, hospitalization cost

To explore the associated factors of patient privacy protection behaviours among nursing interns.The patient privacy protection behaviours of nursing interns are closely related to information security incidents and the quality of clinical practice. However, little is known about the associated factors of patient privacy protection behaviours among nursing interns.A cross-sectional study.A comprehensive hospital in Hunan Province, China.Nursing interns in a comprehensive hospital from 30 different nursing schools were recruited using convenience sampling.Data on general information, patient privacy protection cognition, moral sensitivity, empathy and patient privacy protection behaviours were collected with a general information questionnaire and corresponding scales with good psychometric properties. U-test, spearman correlation analysis and multiple linear regression were used to determine the associated factors of patient privacy protection behaviours among nursing interns.This study showed that nursing interns in a college programme had better patient privacy protection behaviours than those nursing interns in a baccalaureate programme. Nursing interns who have more knowledge of privacy laws and whose clinical nursing teachers excelled in patient privacy protection might show better patient privacy protection behaviours. Nursing interns with better patient privacy protection cognition, higher moral sensitivity and greater empathy might have better patient privacy protection behaviours.Strengthening nursing interns' knowledge of privacy laws and patient privacy protection cognition, improving their moral sensitivity and empathy and standardising the patient privacy protection behaviours of clinical nursing teachers may can improve the patient privacy protection behaviours of nursing interns. Also, clinical teachers should pay close attention to nursing interns in baccalaureate programmes who are likely to have a lower level of patient privacy protection behaviours and act as role models for them in protecting patient privacy in clinical nursing education.

To investigate the level of stigma and identify its influencing factors among women with termination of pregnancy for fetal anomaly(TOPFA) in China.This was a cross-sectional study design.A total of 469 women with TOPFA were recruited from a tertiary care hospital in China using a convenience sampling method.Women with TOPFA participating in the study completed the Demographic Characteristics Questionnaire, Individual Level Abortion Stigma Scale(ILASS), Acceptance and Action Questionnaire- II scale(AQQ- II), Cognitive Fusion Questionnaire scale (CFQ), Multidimensional Perceived Social Support Scale(MPSS), Responses to Stress Questionnaire (RSQ). Women with TOPFA reported moderate levels of stigma(1.49±0.60). Multiple linear regression showed that correlates influencing their stigma included gestational age (β =0.103, P0.05), psychological flexibility (β =-0.319, P0.01), social support(β =-0.190, P0.01), and disengagement coping(β =0.148, P0.05).Gestational age and disengagement coping are positive predictors of stigma, but psychological flexibility and social support are negative predictors of stigma. Further attention should focus on developing targeted intervention strategies to improve protective and reduce harmful factors to confront the stigma-related challenges faced by women with TOPFA.

This study aimed to investigate whether the impact of workplace violence (WPV) on nurses' mental health varies with mental resilience and coping strategies.Workplace violence is a serious threat to nurses' mental health, and its impact on nurses' mental health is influenced by many factors.A cross-sectional study involving 349 participants was conducted over 12 months. The data were analyzed using SPSS 25.0 and SPSS PROCESS macro.In total, 82.52% of nurses were exposed to WPV. WPV not only affects mental health directly but also indirectly through mental resilience. Coping strategies had a moderating effect among WPV, mental resilience and mental health. When nurses coped with psychological violence with intolerance, WPV had a stronger negative effect on their mental health. When nurses coped with psychological violence with tolerance but coped with physical violence with intolerance, mental resilience had a stronger positive effect on their mental health.Good mental resilience and coping with psychological violence with tolerance while coping with physical violence with intolerance can help buffer WPV and promote mental health.Employers who have a "zero tolerance" policy regarding WPV need to re-examine how they currently operate.

Background Gonorrhoea, caused by Neisseria gonorrhoeae, has spread worldwide. Strains resistant to most antibiotics, including ceftriaxone and azithromycin, have emerged to an alarming level. Rapid testing for N. gonorrhoeae and its antimicrobial resistance will therefore contribute to clinical decision making for early diagnosis and rational drug use. Methods A Cas13a-based assay (specific high-sensitivity enzymatic reporter unlocking; SHERLOCK) was developed for N. gonorrhoeae detection (porA gene) and azithromycin resistance identification (A2059G, C2611T). Assays were evaluated for sensitivity with purified dsDNA and specificity with 17 non-gonococcal strains. Performance of SHERLOCK (porA) was compared with Roche Cobas 4800 using 43 urine samples. Identification of azithromycin resistance mutations (A2059G, C2611T) was evaluated using a total of 84 clinical isolates and 18 urine samples. Lateral flow was tested for this assay as a readout tool. Moreover, we directly assayed 27 urethral swabs from patients with urethritis to evaluate their status in terms of N. gonorrhoeae infection and azithromycin resistance. Results The SHERLOCK assay was successfully developed with a sensitivity of 10 copies/reaction, except 100 copies/reaction for A2059G, and no cross-reaction with other species. Comparison of the SHERLOCK assay with the Cobas 4800 revealed 100% concordance within 18 positive and 25 negative urine samples. Of the 84 isolates, 21 strains with azithromycin resistance mutations were distinguished and further verified by sequencing and MIC determination. In addition, 62.96% (17/27) strains from swab samples were detected with no mutant strains confirmed by sequencing. Conclusions The SHERLOCK assay for rapid N. gonorrhoeae detection combined with azithromycin resistance testing is a promising method for application in clinical practice.

Background: Clinical learning environment is an important stage for nursing students, it will affect the cultivation of professional identity of nursing students. This study to explore the factors influencing the cultivation of professional identity among nursing students in a clinical learning environment. Methods: This was a cross-sectional study.Convenience sampling was applied to recruit 398 nursing students from The Third Xiangya Hospital of Central South University in Hunan Province. After the nursing students completed their clinical learning, data on the participants’ characteristics, professional identification and nursing clinical learning environment were collected. Descriptive statistics, including the mean ± standard deviation, were calculated. The data were analysed by t-test, one-way analysis of variance, Pearson’s correlation analysis and multiple linear regression. Results: The results showed that the nursing students’ highest professional identity score was in professional cognition (16.07±2.78). The nursing students’ professional identity was significantly related to educational background, willingness to choose the nursing major and school level (PConclusion: The clinical learning environment and nursing’ students personal characteristics are the most important factors influencing the professional identity of nursing students. Based on these results, hospitals should flexibly adapt teaching methods according to students’ personal characteristics, improve the professional skills of teachers, and create a good working atmosphere. In addition, faculty members should reform their teaching methods and encourage students to establish good interpersonal relationships to provide more learning opportunities for nursing students and to enhance the recognition of nursing students in the nursing profession.

Background: Subacute thyroiditis (SAT) is a transient and self-limiting inflammatory thyroid disease. There is no clear evidence for specific etiology, but it is generally thought to occur after viral infection. Characteristics of SAT include severe pain of the anterior neck, enlarged firm thyroid, disordered thyroid function, elevated erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), typical ultrasound findings (hypoechoic areas) and low thyroid uptake of radioactive iodine or technetium-99 m because of the destructive etiology of the hyperthyroidism. Evidences showed Xiaochaihu decoction (XCHD) has a significant effect on improving the symptoms of SAT patients. The purpose of this study is to assess the safety and effectiveness of XCHD for patients with SAT. Methods and analysis: The literature that has been identified via searching 6 Chinese electronic databases and eight English electronic databases from inception to September 21, 2020 will be included in the study. Research selection, data extraction as well as research quality assessment will be completed by 2 experienced researchers independently. The primary outcome is remission rate. Data analysis will be conducted by the RevMan 5 software, and GRADE will help to assess the level of evidence. The heterogeneity of data will be investigated by a heterogeneity x2 test, as well as the Higgins I2 test. A subgroup analyses and sensitivity analysis will be conducted to explore the sources of heterogeneity. Results: The results of this study will be published in a peer-reviewed journal. Conclusion: This study will draw a conclusion about whether XCHD is safe and effective in treating SAT on the basis of evidence-based medicine. This conclusion will provide areliable scientific evidence for the alternative treatment for the management of SAT. OSF registration number: https://osf.io/8hbue.

Casticin, an active compound isolated from Vitex Fructus, has been reported to have anti-inflammatory effects in previous studies. The present study was designed to evaluate the protective effects of casticin on lipopolysaccharide (LPS)-induced acute lung injury (ALI) and clarify the underlying mechanisms. ALI was induced by intratracheal instillation of LPS. Casticin was administrated 1 h before or after LPS challenge. The results showed that casticin decreased LPS-induced lung histopathological changes, MPO activity, and lung wet/dry weight ratio. Casticin also inhibited the numbers of inflammatory cells and the levels of inflammatory cytokines TNF-α, IL-6, and IL-1β production. Furthermore, casticin suppressed LPS-induced NF-κB activation, and NLRP3, ASC, and caspase-1 expression. In conclusion, the results suggested that casticin had a protective effect against LPS-induced ALI. Casticin protected against LPS-induced ALI by inhibiting inflammatory cytokines production through the inhibition of NF-κB and NLRP3 signaling pathways.

Tuberculosis (TB) is a serious disease that is characterized by Mycobacterium tuberculosis (M.tb)-triggered immune system impairment and lung tissue damage shows limited treatment options. MicroRNAs (miRNAs) are regulators of gene expression that play critical roles in many human diseases, and can be up- or downregulated by M.tb infection in macrophage. Recently, tissue inhibitor of matrix metalloproteinase (TIMP) 3 has been found to play roles in regulating macrophage inflammation. Here, we found that TIMP3 expression was regulated by miR-206 in M.tb-infected THP-1 human macrophages. In THP-1 cells infected with M.tb, the miR-206 level was significantly upregulated and the expression of TIMP3 was markedly decreased when the secretion of inflammatory cytokines was increased. Inhibition of miR-206 markedly suppressed inflammatory cytokine secretion and upregulated the expression of TIMP3. In contrast, the upregulation of miR-206 promoted the matrix metalloproteinase (MMP) 9 levels and inhibited TIMP3 levels. Using a dual-luciferase reporter assay, a direct interaction between miR-206 and the 3'-untranslated region (UTR) of TIMP3 was confirmed. SiTIMP3, the small interfering RNA (siRNA) specific for TIMP3, significantly attenuated the suppressive effects of miR-206-inhibitor on inflammatory cytokine secretion and MMP9 expression. Our data suggest that miR-206 may function as an inflammatory regulator and drive the expression of MMP9 in M.tb-infected THP-1 cells by targeting TIMP3, indicating that miR-206 is a potential therapeutic target for patients with TB.

Objectives The aim of this study is to understand the feelings and experiences of nursing undergraduates who participate in pre-hospital first aid and to explore the training programme of pre-hospital first aid for nursing undergraduates. The main objective is to provide a reference for the reform of pre-hospital first aid teaching in undergraduate colleges. Methods Semi-structured interviews were conducted with 16 nursing undergraduates who had participated in pre-hospital first aid in an ambulance from a teaching hospital in Hunan, China. The interview data were transcribed, and Colaizzi's seven-step method was used for subject analysis. Results The experiences of undergraduate nursing interns can be summarized into five themes: helplessness and fear of death, uncertainty of unknown events, satisfaction with self-improvement, need for professional competence, and the perception of a gap in pre-hospital emergency resources. Conclusions Nursing colleges and teaching hospitals should pay attention to death education and pre-hospital first aid training. Teachers should be able to apply situational teaching methods to pre-hospital first-aid teaching and should focus on cultivating the comprehensive abilities of nursing students. At the same time, schools and teaching hospitals should also strengthen the cultivation of professional identity during pre-hospital first aid practice to reduce the rate of nursing personnel turnover. It's very important to supplement and retain professional nurses for the pre-hospital first aid.

Tenuigenin (TEN), the main active component of Polygala tenuifolia, has been reported to have anti-inflammatory effects. However, the effects of TEN on IL-1β-stimulated osteoarthritis chondrocytes have not been reported. The purpose of this study was to investigate the anti-inflammatory effects and mechanism of TEN on IL-1β-stimulated human osteoarthritis chondrocytes. Human osteoarthritis chondrocytes were pretreated with or without TEN for 1 h and then stimulated with IL-1β. The production of NO and PGE2 were detected by the Griess reagent and ELISA. The expression of NF-κB and MAPKs (p38, JNK, ERK) were measured by Western blot analysis. The production of MMP-1, MMP3, and MMP13 were measured by ELISA. The results showed that treatment of TEN significantly inhibited IL-1β-induced NO and PGE2 production. TEN also suppressed IL-1β-induced MMP-1, MMP3, and MMP13 expression. Furthermore, TEN was found to inhibit IL-1β-induced NF-κB activation, PI3K, and AKT phosphorylation. In conclusion, these results suggest that TEN inhibits IL-1β-induced inflammation in human osteoarthritis chondrocytes by inhibiting PI3K/AKT/NF-κB signaling pathway.

There is a need for improved and up-to-date land use/land cover (LULC) data sets over an intensively changing area in the Amur River Basin (ARB) in support of science and policy applications focused on understanding of the role and response of the LULC to environmental change issues. The main goal of this study was to map LULC in the ARB using MODIS 250-m Normalized Difference Vegetation Index (NDVI), Land Surface Vegetation Index (LSWI), and reflectance time series data for 2001 and 2007. Another goal was to test the consistency of the classification results using relatively coarse resolution MODIS imagery data in order to develop a methodology for rapid production of an up-to-date LULC data set. The results on MODIS land cover were evaluated using existing land use/cover data as derived from Landsat TM data. It was found that the MODIS 250-m NDVI data sets featured sufficient spatial, spectral and temporal resolution to detect unique multi-temporal signatures for the region’s major land cover types. It turned out that MODIS 250 NDVI time series data have high potential for large-basin land use/land cover monitoring and information updating for purposes of environmental basin research and management.

In this study, we present spectral measurements of corn chlorophyll content in Changchun (eight times in 2003) and Hailun (five time in 2004), both of which lie in the Songnen Plain, China. Corn canopy reflectance and its derivative reflectance were subsequently used in a linear regression analysis against Chl-a concentration on one by one spectral reflectance. It was found that determination coefficient for Chl-a concentration was high in blue, red and near infrared spectral region, and it was low in green and red edge spectral region, however Chl-a concentration obtained its high determination coefficient in blue, green and red edge spectral region, especially in red edge region with derivative reflectance. Regression models were established based upon 6 spectral vegetation indices and wavelet coefficient, reflectance principal components as well. It was found that wavelet transforms is an effective method of hyperspectral reflectance feature extraction for corn Chl-a estimation, and the best multivariable regressions obtain determination coefficient (R 2 ) up to 0.87 for Chl-a concentration. Finally, neural network algorithms with both specific band reflectance and wavelet coefficient as input variables were applied to estimate corn chlorophyll concentration. The results indicate that estimation accuracy improved with nodes number increasing in the hidden layer, and neural network performs better with wavelet coefficient than that with specific band reflectance as input variables, determination coefficient was up to 0.96 for Chl-a concentration. Further studies are still needed to refine the methods for determining and estimating corn bio-physical/chemical parameters or other vegetation as well in the future.

In this study, we present spectral measurements of soybean LAI and their estimation from reflectance spectra data in Songnen Plain. Soybean canopy reflectance and its derivative were subsequently used in a linear regression analysis against LAI on one by one spectral reflectance. It was found that determination coefficient for LAI was high in blue, red and near infrared spectral region, and it was low in green spectral region, however LAI obtained its high determination coefficient in blue, green and red edge spectral region, especially in red edge region. Regression models were established based upon spectral vegetation indices and wavelet energy coefficient. It was found that wavelet transforms is an effective method for hyperspectral reflectance variables extraction to retrieve LAI, and the best multivariable regressions R2 up to 0.90 for LAI. Further studies are still needed to refine the methods for determining and estimating corn bio-physical/chemical parameters or other physiological parameters of different vegetation as well in the future.

The Heilongjiang Basin (HLB) located between N43° to N57° and E108° to E141° is a seasonal snow covered region. The monitoring of snow covered areas (SCA) and snow water equivalent (SWE) at regional scale are essential for climate and hydrological applications. Optical and microwave remote sensing have their own advantages and disadvantages for monitoring snow covered areas. In this study, we present the preliminary validation results of snow cover product produced by National Snow and Ice Data Centre (NSIDC) of USA using satellite data from Advanced Microwave Scanning Radiometer-EOS (AMSR-E) on board Aqua satellite and optical remote sensing data from Terra/MODIS over the HLB region. The data consist of snow cover and snow water equivalent product for the winters from 2002 to 2008 of coarse resolution and relative fine resolution of MODIS snow cover data for the winter of 2007-08. Our primary result indicates that AMSR-E snow product tends to overestimate snow covered area of the region, and snow cover extent derived from MOD10A2 more objectively reflects the truth. Our result also indicates that elevation is not a significant factor affecting snow covered area distribution in our study region, however, land use/cover do affect the accuracy of the snow cover product, especially in forested distribution areas. In the future, we will have several more test sites in Northeast China, representing the two main types of land-cover categories: forested and agricultural areas for accurately snow cover monitoring.

China has witnessed fast urban growth in recent decades. In this study, remote sensing data from both Landsat-5 TM and Landsat-7 ETM+ were utilized to assess the spatial-temporal characteristics of the urban area in Shenyang in northeast China. To quantitatively determine urban land use extents and development densities, land use/cover were mapped for 8 periods from 1986 to 2007 around the urban and suburban area in Shenyang. The urban-rural boundaries and urban development densities were defined by selecting certain imperviousness threshold values and Landsat thermal bands were used to investigate the thermal patterns of urban surface. Analysis results suggest that urban surface thermal characteristics and patterns can be identified qualitatively based on the urban land use and development density data. Results show that the urban area of Shenyang has an obvious daytime heating effect (heat-source). These thermal effects are strongly correlated with urban development densities i.e. higher percentage imperviousness is usually associated with higher surface temperature. Using vegetation canopy coverage information, the spatial and temporal distributions of urban impervious surface and associated thermal characteristics were demonstrated to be very useful source in quantifying urban land use, development intensity, and urban thermal patterns.

Improved and up-to-date land use/land cover (LULC) data sets are needed over intensively land use/cover change area in the Amur River Basin (ARB) to support science and policy applications focused on understanding of the role and response of the LULC to environmental change issues. The main goal of this study was to map LULC in the Amur River Basin using MODIS 250 m Normalized Difference Vegetation Index (NDVI) and Land Surface Water Index (LSWI) time series data in 2001 and 2007. A combination of unsupervised ISODATA and hierarchical decision tree classification were performed on 12-month time-series of MODIS NDVI data over the study region. The MODIS land cover result of Northeast China was evaluated using existing land use/cover data, and the rest part was evaluated by LULC information derived from LANDSAT-TM. MODIS 250m NDVI, LSWI and reflectance datasets were found to have sufficient spatial, spectral, and temporal resolutions to detect unique multitemporal signatures of the major land cover types over the region. The overall classification accuracy was 0.81 and the kappa coefficient is 0.64. In conclusion, this method has been used successively for LULC change monitoring in the year 2001 and 2007. The result indicate that MODIS 250 NDVI time series data can derive relatively accurate LULC information for hydrological and climate modeling.

This study focused on actual Evapotranspiration (ET) characterization in Coleambally Irrigation Area (CIA), Murrubidgee Irrigation Area (MIA) and its ambient region using the SEBAL model with remotely sensed TERRA/MODIS, NOAA/AVHRR and Landsat-5 TM data in the Area Of Interest (AOI) for the National Airborne Field Experimentation (NAFE06) campaign in 2006. Results showed that actual ET estimated from NOAA AVHRR 18 was always overestimating as comparison to Eddy system (on average 38%) during the image acquisition dates. However, for the same image acquisition dates, TERRA/MODIS ET ranges from 3.7% lower to 21.7% higher than the Eddy system. Landsat 5 TM modeled ET results were comparable to the Eddy Covariance system having a minor error with an average of 4.09%. It was proven possible to simultaneously use SEBAL for different sensors with the combination of high spatial and temporal resolution to estimate ET spatial distribution characteristics though the accuracy of NOAA-AVHRR derived result is not ideal. Considering the lack of high spatial resolution thermal satellite and need of time-series ET dynamics, the MODIS data could be used to provide seasonal actual ET for regional studies. The combination of MODIS and Landsat can be a better choice for future ET study at catchments scale.

Improved and up-to-date land use/land cover (LULC) data sets are needed over the whole country of Australia to support science and policy applications focused on understanding the role and response of the LULC to environmental change. The main goal of this study was to map LULC in Australia using MODIS 250 m Normalized Difference Vegetation Index (NDVI), Land Surface Vegetation Index (LSWI) and reflectance time series data of 2000 and 2003. NDVI time-series were filtered by the Savitzky-Golay algorithm in the present study to smooth out noise. A combination of unsupervised ISODATA and a hierarchical decision tree classification were performed on 2 years 12-month time-series MODIS data. Also, Australian Vegetation Map and other land use/land cover data set were used as labeling reference during the classification process. The MODIS land cover products were evaluated using existing land use/cover data derived from Landsat TM as reference data (AUS-2000), also LULC information derived from 11 scenes of Landsat-5 TM data were used as validation data source. The overall classification accuracy was 76.4%. It turned out that our result is acceptable because the relative high resolution of MODIS data and more prior knowledge was applied.

The Songnen Plain is an important commodity grain product base in China for which a spatiotemporal pattern of actual evapotranspiration (ETa) would provide critical important information to evaluate crop growth status and water use efficiency. ETa over the Songnen Plain in the 2008 growing season (from May to September) was mapped using the moderate resolution imaging spectroradiometer time-series products based on the surface energy balance algorithm for land model and the Penman-Monteith equation. The estimated ETa was validated using eddy covariance surface data. The calculated and observed ETa values were highly consistent with a total difference of 18.26% in the whole growing season. Therefore, the ETa retrieval method based on remote sensing technology could satisfy the requirements for regional ETa estimation over the Songnen Plain. The total ETa over the Songnen Plain in the 2008 growing season ranged from 182.7 to 1002.4 mm, and the average value for the whole study area was 591.1 ± 122.2 mm (standard deviation). ETa exhibited obvious spatial variation, gradually increasing from low values in the southwest to higher values in the east and northeast. Monthly ETa varied with meteorological conditions, land covers, root-zone soil moisture, and vegetation phenology. Higher monthly ETa values appeared in June, July, and August with a maximum value of 139.5 mm observed in July. The average monthly ETa for water-body, woodland, and wetland was much higher than cropland and grassland during the growing season. Grassland obtained the lowest monthly ETa due to the scarcity of rainfall and lower groundwater level.