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Improvement, Comparison, and Application of Field Measurement Methods for Grassland Vegetation Fractional Coverage

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Journal of Integrative Plant Biology 2005年第9期47卷 1074-1083页

作者： Xiao-bing li Yun-Hao chen Hua YANG Yun-Xia ZHANG College of Resources Sciences and Technology Key Laboratory of Environmental Change and Natural Disaster of the Ministry of Education Beijing Normal University Beijing 100875 China

As one of the important vegetation parameters, vegetation fractional coverage （VFC） is more difficult to measure accurately among a good many parameters of plant communities. The temperate typical steppe in the north of China was chosen for investigation in the present study and a digital camera was used to measure herb community coverage in the field, adopting methods of ocular estimation, gridding measurement, visual interpretation, supervised classification, and information extraction of color spatial transformation to calculate the VFC of images captured by the digital camera. In addition VFC calculated by various methods was analyzed and compared VFC, enabling us to propose an effective method for measuring VFC using a digital camera. The results of the present study indicate that：（i） as two common useful and effective methods of measuring VFC with a digital camera, not only does the error of estimated values of visual estimation and supervised classification vary considerably, but the degree of automatization is very low and depends, to a great extent, on the manipulator; （ii） although the method of visual interpretation may assure the precision of the calculated VFC and enable the precision of results obtained using other methods to be determined, as far as large quantities of data are concerned, this method has the disadvantages of wasting time and energy, and the applications of this method are limited; （iii） the precision and stability of VFC calculated using the grid and node method are superior to those of visual estimation and supervised classification and inferior to those of visual interpretation, but, as for visual interpretation and supervised classification, gridding measurements are difficult to apply in practice because they are not time efficient; and （iv） in terms of the precision of calculation of the VFC, an information-extracting model based on an intensity, hue, saturation （IHS） color space-multi-component series segmentation strategy is s

关键词： color space transformation digital camera field measurement grassland vegetationfractional coverage.

BOTTOM SHEAR STRESS UNDER WAVE-CURRENT INTERACTION

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Journal of Hydrodynamics 2008年第1期20卷 88-95页

作者： liANG bing-chen li Hua-jun LEE Dong-yong College of Engineering Ocean University of China Qingdao 266100 China Coastal and Harbour Engineering Research Center Korea Ocean Research and Developmcnt Institute Ansan Korea

The present work adopts the COHERENS-SWAN model developed by the first author through coupling three-dimensional hydrodynamic model （COHERENS） and third-generation wave model （SWAN）. Inside the COHERENS-SWAN, the SWAN is regarded as a subroutine and the time- and space-varying current velocity and surface elevation are obtained from the COHERENS. Wave-enhanced bottom shear stress, wave induced surface mixing length and wave dependent surface drag coefficient have been introduced into the COHERENS. Secondly, as wave-enhanced bottom shear stress （＂bottom shear stress＂ described as BSS sometimes in this article） is concerned, a modified bottom shear stress Grant and Madsen model which introduces random wave field is given and introduced to COHERENS-SWAN. COHERENS-SWAN is also adopted to simulate three-dimensional flow in the Yellow River Delta with wave-current co-existing. Four numerical experiments were given to study the effects of wave-current interaction on enhancing bottom shear stress. The simulated current velocities, wave height and wave period match well with field measurement data. The simulated significant wave height and wave period for the case with considering the effects of current can give better agreement with measurement data than the case without involving the effects of current. The introduction of random wave generates lower the bottom shear stress than the case without introducing it. There are obvious differences between bottom shear stress of two way interaction and one way interaction. Velocity field obtained by the COHERENS-SWAN is reasonable according to previous studies and measurements.

关键词： Yellow River Delta COHERENS SWAN wave-current interaction bottom shear stress

RNA interference and its application in plants

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Forestry Studies in China 2008年第4期10卷 280-284页

作者： ZHOU bing-bin li Wei chen Xiao-yang Key Laboratory for Genetics and Breeding in Forest Trees and Ornamental Plants of Ministry of Education Beijing Forestry University Beijing 100083 P. R. China

RNA interference （RNAi）, a process that inhibits gene expression by the double-stranded RNA （dsRNA）, causes the degradation of target messenger RNA molecules. RNAi exists in almost all organisms. We review the recent history of RNAi studies, RNAi molecular mechanisms, characteristics and RNAi applications in higher plants. At the same time, the prospect of RNAi applications in functional genomics and genetic improvement of higher plants and possible future problems and possibilities are also discussed.

关键词： RNA interference functional genomics genetic improvement antivirus

Extensive identification of landslide boundaries using remote sensing images and deep learning method

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China Geology 2024年第2期7卷 277-290页

作者： Chang-dong li Peng-fei Feng Xi-hui Jiang Shuang Zhang Jie Meng bing-chen li Faculty of Engineering China University of GeoscienceWuhan 430074China Badong National Observation and Research Station of Geohazards China University of GeosciencesWuhan 430074China School of Mechanical Engineering and Electronic Information China University of GeosciencesWuhan 430074China College of Geology Engineering and Geomatics Chang’an UniversityXi’an 710054China

The frequent occurrence of extreme weather events has rendered numerous landslides to a global natural disaster *** is crucial to rapidly and accurately determine the boundaries of landslides for geohazards evaluation and emergency ***,the Skip Connection DeepLab neural network(SCDnn),a deep learning model based on 770 optical remote sensing images of landslide,is proposed to improve the accuracy of landslide boundary *** SCDnn model is optimized for the over-segmentation issue which occurs in conventional deep learning models when there is a significant degree of similarity between topographical geomorphic *** exhibits notable improvements in landslide feature extraction and semantic segmentation by combining an enhanced Atrous Spatial Pyramid Convolutional Block(ASPC)with a coding structure that reduces model *** experimental results demonstrate that SCDnn can identify landslide boundaries in 119 images with MIoU values between 0.8and 0.9;while 52 images with MIoU values exceeding 0.9,which exceeds the identification accuracy of existing *** work can offer a novel technique for the automatic extensive identification of landslide boundaries in remote sensing images in addition to establishing the groundwork for future inve stigations and applications in related domains.

关键词： Geohazard Landslide boundary detection Remote sensing image Deep learning model Steep slope Large annual rainfall Human settlements Infrastructure Agricultural land Eastern Tibetan Plateau Geological hazards survey engineering

Differential diagnosis and laparoscopic treatment of adrenal pheochromocytoma and ganglioneuroma

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Chinese Medical Journal 2009年第15期122卷 1790-1793页

作者： SHI bing-bing li Han-zhong chen cheng RONG Shi FAN Hua WEN Jin li Hong-jun Department of Urology Peking Union Medical College Hospital Chinese Academy of Medical Sciences Beijing 100730 China

Background Adrenal ganglioneuroma is a rare adrenal pathogenic disease with difficult differential diagnosis from adrenal pheochromocytoma. Currently, very limited literature is available to allow a differential diagnosis of these two conditions from each other. This study aimed to evaluate the clinical profile, differential diagnosis and surgical treatments of both conditions. Methods Clinical characteristics of 36 patients with adrenal pheocheomocytoma and 18 patients with adrenal ganglioneuroma were analyzed. Data from CT scans and surgical treatments from 1999 to 2007 were collected. Endocrine hormone tests and ^131I-metaiodobenzylguanidine （MIBG） were performed. Neither ^131I-MIBG nor endocrine hormone tests were available in 9 cases of asymptomatic adrenal ganglioneuroma with tumor size less than 4 cm and there were negative findings from contrast enhanced CT scans. The level of urine catecholamine of patients was compared by one-way analysis of variance. Results The mean age of patients in the adrenal ganglioneuroma group was 41.2 years （16-67 year） and in the adrenal pheochromocytoma patients 38 years （17-74 year）. Contrast enhanced CT showed that the foci were intensified in 5 cases （27.8%） of adrenal ganglioneuroma and there were obvious contrast indications in 30 （83.3%） of the pheochromocytoma. Catecholamine levels in a 24-hour urine sample were normal in 4 patients with adrenal ganglioneuroma and increased in 36 （100%） cases with adrenal pheochromocytoma. ^131I-MIBG nuclear scan showed negative results in 4 patients （100%） with adrenal ganglioneuroma and positive results in 25 （96.2%） with adrenal pheochromocytom. Laparoscopy for adrenal tumors was performed through a transperitoneal or retroperitoneal approach during a follow-up period of （43±6） months, and all cases survived well. Conclusions CT, urinary catecholamine and ^131I-MIBG are standard and efficient tools for differential diagnosis of adrenal ganglioneuroma from pheochromocytoma. Laparoscopi

关键词： pheochromocytoma ganglioneuroma, laparoscopy

“Focusing on Treating the Spirit(神)”in Acupuncture and Moxibustion:The Dialectical Unity of Regulating the Body and the Spirit

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Chinese Medicine and Culture 2021年第1期4卷 19-24页

作者： bing-li chen Qian Fan li-Xin Guan Wen-Guang Hou Yue-Lai chen Acupuncture Department Yueyang Hospital of Integrated Traditional Chinese and Western MedicineShanghai University of Traditional Chinese MedicineShanghai 200437China

“Focusing on treating the spirit(神)”is an important principle in acupuncture and *** is a unique psychosomatic therapy involving the doctor and the patient,which includes regulating the spirit and the *** Chinese medicine attaches great importance to *** on treating the spirit is also a component of the standards of medical *** when doctors have noble medical ethics can they achieve clinical treatment of the mind and give full play to their skills to cure *** on treating the spirit runs through the entire clinical process of acupuncture and *** the treatment,it is necessary to focus on the spirit to distinguish the spirit and *** the treatment,attention should be paid to the mind to regulate the spirit and *** is the premise of clinical diagnosis and treatment of acupuncture and moxibustion and the key to the curative *** on treating the spirit is also in the realm of doctor-patient double treatment,which requires doctor-patient communication before treatment and the preservation of the body and spirit after ***,concentration of the mind is the key to acupuncture and moxibustion treatment.

关键词： Acupuncture and moxibustion regulating the body regulating the spirit(神) treating the spirit(神)

Peripheral blood RNA biomarkers can predict lesion severity in degenerative cervical myelopathy

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Neural Regeneration Research 2025年第6期20卷 1764-1775页

作者： Zhenzhong Zheng Jialin chen Jinghong Xu Bin Jiang Lei li Yawei li Yuliang Dai bing Wang Department of Spine Surgery The Second Xiangya Hospital of Central South UniversityChangshaHunan ProvinceChina

Degenerative cervical myelopathy is a common cause of spinal cord injury,with longer symptom duration and higher myelopathy severity indicating a worse *** numerous studies have investigated serological biomarkers for acute spinal cord injury,few studies have explored such biomarkers for diagnosing degenerative cervical *** study involved 30 patients with degenerative cervical myelopathy(51.3±7.3 years old,12 women and 18 men),seven healthy controls(25.7±1.7 years old,one woman and six men),and nine patients with cervical spondylotic radiculopathy(51.9±8.6 years old,three women and six men).Analysis of blood samples from the three groups showed clear differences in transcriptomic *** analysis identified 128 differentially expressed genes that were enriched in patients with neurological *** least absolute shrinkage and selection operator analysis,we constructed a five-gene model(TBCD,TPM2,PNKD,EIF4G2,and AP5Z1)to diagnose degenerative cervical myelopathy with an accuracy of 93.5%.One-gene models(TCAP and SDHA)identified mild and severe degenerative cervical myelopathy with accuracies of 83.3%and 76.7%,*** of two immune cell types(memory B cells and memory-activated CD4^(+)T cells)predicted levels of lesions in degenerative cervical myelopathy with 80%*** results suggest that peripheral blood RNA biomarkers could be used to predict lesion severity in degenerative cervical myelopathy.

关键词： biomarkers candidate genes degenerative cervical myelopathy gene expression analysis immune cell types neurological disabilities peripheral blood RNA profiles spinal cord injury

Cell polarization in ischemic stroke: molecular mechanisms and advances

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Neural Regeneration Research 2025年第3期20卷 632-645页

作者： Yuanwei li Xiaoxiao Xu Xuan Wu Jiarui li Shiling chen Danyang chen Gaigai li Zhouping Tang Department of Neurology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

Ischemic stroke is a cerebrovascular disease associated with high mortality and disability rates. Since the inflammation and immune response play a central role in driving ischemic damage, it becomes essential to modulate excessive inflammatory reactions to promote cell survival and facilitate tissue repair around the injury site. Various cell types are involved in the inflammatory response, including microglia, astrocytes, and neutrophils, each exhibiting distinct phenotypic profiles upon stimulation. They display either proinflammatory or anti-inflammatory states, a phenomenon known as ‘cell polarization.’ There are two cell polarization therapy strategies. The first involves inducing cells into a neuroprotective phenotype in vitro, then reintroducing them autologously. The second approach utilizes small molecular substances to directly affect cells in vivo. In this review, we elucidate the polarization dynamics of the three reactive cell populations(microglia, astrocytes, and neutrophils) in the context of ischemic stroke, and provide a comprehensive summary of the molecular mechanisms involved in their phenotypic switching. By unraveling the complexity of cell polarization, we hope to offer insights for future research on neuroinflammation and novel therapeutic strategies for ischemic stroke.

关键词： astrocyte polarization immune regulation inflammation ischemic injury microglia polarization neutrophil polarization signaling pathways stroke

Engineering atomic Rb-N configurations to tune radical pathways for highly selective photocatalytic H2O2 synthesis coupled with biomass valorization

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Journal of Energy Chemistry 2025年第1期100卷 215-225页

作者： Jiaye li Shuang Pan Yihuang chen Qiong liu College of Chemistry and Materials Engineering Wenzhou University Guangdong Provincial Key Laboratory of Chemical Measurement and Emergency Test Technology (China) Institute of Analysis Guangdong Academy of Sciences (China National Analytical CenterGuangzhou)

Photocatalytic oxygen reduction for hydrogen peroxide （H2O2） synthesis presents a green and costeffective production ***,achieving highly selective H2O2synthesis remains challenging,necessitating precise control over free radical reaction pathways and minimizing undesirable oxidative ***,we report for the visible light-driven simultaneous co-photocatalytic reduction of O2to H2O2and oxidation of biomass using the atomic rubidium-nitride modified carbon nitride（CNRb）.The optimized CNRb catalyst demonstrates a record photoreduction rate of 8.01 mM h-1for H2O2generation and photooxidation rate of 3.75 mM h-1for furfuryl alcohol to furoic acid,achieving a remarkable solar-to-chemical conversion （SCC） efficiency of up to 2.27%.Experimental characterizations and DFT calculation disclosed that the introducing atomic Rb–N configurations allows for the high-selective generation of superoxide radicals while suppressing hydroxyl free radical *** is because the Rb–N serves as the new alternative site to perceive a stronger connection position for O2adsorption and reinforce the capability to extract protons,thereby triggering a high selective redox product *** study holds great potential in precisely regulating reactive radical processes at the atomic level,thereby paving the way for efficient synthesis of H2O2coupled with biomass valorization.

关键词： Atomic economy Radical pathway regulation Rubidium atom coordination Biomass valorization