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Design of Low-Power Data Logger of Deep Sea for Long-Term Field Observation 被引量:1
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作者 赵伟 陈鹰 +2 位作者 杨灿军 曹建伟 顾临怡 《China Ocean Engineering》 SCIE EI 2009年第1期133-144,共12页
This paper describes the implementation of a data logger for the real-time in-situ monitoring of hydrothermal systems. A compact mechanical structure ensures the security and reliability of data logger when used under... This paper describes the implementation of a data logger for the real-time in-situ monitoring of hydrothermal systems. A compact mechanical structure ensures the security and reliability of data logger when used under deep sea. The data logger is a battery powered instrument, which can connect chemical sensors (pH electrode, H2S electrode, H2 electrode) and temperature sensors. In order to achieve major energy savings, dynamic power management is implemented in hardware design and software design. The working current of the data logger in idle mode and active mode is 15 μA and 1.44 mA respectively, which greatly extends the working time of battery. The data logger has been successftdly tested in the first Sino-American Cooperative Deep Submergence Project from August 13 to September 3, 2005. 展开更多
关键词 data logger low-power design deep sea long-term monitoring
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The Long-Term Field Experiment Observatory and Preliminary Analysis of Land-Atmosphere Interaction over Hilly Zone in the Subtropical Monsoon Region of Southern China 被引量:2
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作者 LIU Jian-Guo XIE Zheng-Hui +8 位作者 JIA Bing-Hao TIAN Xiang-Jun QIN Pei-Hua ZOU Jing YU Yan SUN Qin WANG Yuan-Yuan XIE Jin-Bo XIE Zhi-Peng 《Atmospheric and Oceanic Science Letters》 CSCD 2013年第4期203-209,共7页
To improve current understanding of the water cycle,energy partitioning and CO2 exchange over hilly zone vegetative land surfaces in the subtropical monsoon environment of southern China,a long-term field experiment o... To improve current understanding of the water cycle,energy partitioning and CO2 exchange over hilly zone vegetative land surfaces in the subtropical monsoon environment of southern China,a long-term field experiment observatory was set up at Ningxiang,eastern Hunan Province.This paper presents a preliminary analysis of the field observations at the observatory collected from August to November 2012.Results show that significant diurnal variations in soil temperature occur only in shallow soil layers(0.05,0.10,and 0.20 m),and that heavy rainfall affects soil moisture in the deep layers(≥ 0.40 m).During the experimental period,significant diurnal variations in albedo,radiation components,energy components,and CO2 flux were observed,but little seasonal variation.Strong photosynthesis in the vegetation canopy enhanced the CO2 absorption and the latent heat released in daylight hours;Latent heat of evaporation was the main consumer of available energy in late summer.Because the field experiment data are demonstrably reliable,the observatory will provide reliable long-term measurements for future investigations of the land-atmosphere interaction over hilly land surfaces in the subtropical monsoon region of southern China. 展开更多
关键词 field observation subtropical monsoon reion hilly zone surface flux land-atmosohere interaction
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Study of contents of selenium and arsenic in soil—A long-term field experiment
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作者 Béla Kovács Eva Széles +1 位作者 József Prokisch Zoltán Gyori 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期198-198,共1页
关键词 ICP-MS 土壤化学 化学元素
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Imperative for long-term management and surveillance in Kawasaki disease
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作者 Yan Pan Fu-Yong Jiao 《World Journal of Clinical Cases》 SCIE 2025年第4期61-63,共3页
Kawasaki disease(KD)is a significant pediatric vasculitis known for its potential to cause severe coronary artery complications.Despite the effectiveness of initial treatments,such as intravenous immunoglobulin,KD pat... Kawasaki disease(KD)is a significant pediatric vasculitis known for its potential to cause severe coronary artery complications.Despite the effectiveness of initial treatments,such as intravenous immunoglobulin,KD patients can experience long-term cardiovascular issues,as evidenced by a recent case report of an adult who suffered a ST-segment elevation myocardial infarction due to previous KD in the World Journal of Clinical Cases.This editorial emphasizes the critical need for long-term management and regular surveillance to prevent such complications.By drawing on recent research and case studies,we advocate for a structured approach to follow-up care that includes routine cardiac evaluations and preventive measures. 展开更多
关键词 Kawasaki disease long-term management Coronary artery aneurysm SURVEILLANCE Preventive care
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Effects of Long-Term Organic Amendments on Soil Organic Carbon in a Paddy Field: A Case Study on Red Soil 被引量:9
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作者 HUANG Qing-hai LI Da-ming +8 位作者 LIU Kai-lou YU Xi-chu YE Hui-cai HU Hui-wen XU Xiao-lin WANG Sai-lian ZHOU Li-jun DUAN Ying-hua ZHANG Wen-ju 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第3期570-576,共7页
Soil organic carbon (SOC) is one of the main carbon reservoirs in the terrestrial ecosystem. It is important to study SOC dynamics and effects of organic carbon amendments in paddy fields because of their vest expan... Soil organic carbon (SOC) is one of the main carbon reservoirs in the terrestrial ecosystem. It is important to study SOC dynamics and effects of organic carbon amendments in paddy fields because of their vest expansion in south China. A study was carried out to evaluate the relationship between the SOC content and organic carbon input under various organic amendments at a long-term fertilization experiment that was established on a red soil under a double rice cropping system in 1981. The treatments included non-fertilization (CK), nitrogen-phosphorus-potassium fertilization in early rice only (NPK), green manure (Astragalus sinicus L.) in early rice only (OM1), high rate of green manure in early rice only (OM2), combined green manure in early rice and farmyard manure in late rice (OM3), combined green manure in early rice, farmyard manure in late rice and rice straw mulching in winter (OM4), combined green manure in early rice and rice straw mulching in winter (OMS). Our data showed that the SOC content was the highest under OM3 and OM4, followed by OM1, OM2 and OM5, then NPK fertilization, and the lowest under non-fertilization. However, our analyses in SOC stock indicated a significant difference between OM3 (33.9 t ha^-1) and OM4 (31.8 t ha^-1), but no difference between NPK fertilization (27 t ha^-1) and nonfertilization (28.1 t ha^-1). There was a significant linear increase in SOC over time for all treatments, and the slop of linear equation was greater in organic manure treatments (0.276-0.344 g kg-1 yr^-1) than in chemical fertilizer (0.216 g kg^-1 yr^-1) and no fertilizer (0.127 g kg^-1 yr^-1). 展开更多
关键词 long-term field experiment organic amendments soil organic carbon paddy soil derived from red earth
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Effects of Long-term Fertilization on Soil M icrobial Com m unity Structure,Labile Organic Carbon and Nitrogen and Enzym e Activity in Paddy Field and Upland 被引量:4
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作者 Wang Guiyue Su Ting +3 位作者 Han Hailiang Tan Heping Bao Fei Zhao Fucheng 《Meteorological and Environmental Research》 CAS 2019年第5期105-111,共7页
To investigate the effects of long-term fertilization systems on soil microbial community structure,labile organic carbon and nitrogen and enzyme activity in yellow sand paddy field and upland,a field experiment was c... To investigate the effects of long-term fertilization systems on soil microbial community structure,labile organic carbon and nitrogen and enzyme activity in yellow sand paddy field and upland,a field experiment was conducted at the experimental station of Dongyang Institute of Maize Research in Zhejiang Province,China in 2009.The experiment consisted of six treatments with three replicates,and they were arranged in a completely randomized design,including no fertilization in paddy field (PCK),conventional fertilization in paddy field (PCF),formulated fertilization by soil testing in paddy field (PSTF),formulated fertilization by soil testing with organic manure in paddy field (PSTF+OF),conventional fertilization on upland (DCF),and formulated fertilization by soil testing with organic manure on upland (DSTF+OF).Soil nutrients,enzyme activity,microbial biomass and community structure were determined in 2015.The results showed that compared with no fertilization in paddy field (PCK),fertilization increased soil phosphorus and potassium content,and decreased pH value.No fertilization in paddy field (PCK) had no significant effect on soil culturable microorganisms in paddy field and upland,but formulated fertilization by soil testing with organic manure on upland (DSTF+OF) significantly increased the number of fungi.Formula fertilization by soil testing with organic manure (PSTF+OF) also significantly increased soil microbial biomass carbon and nitrogen in paddy field and upland.Moreover,fertilization had no significant effect on soil cellulase activity,but formula fertilization by soil testing with organic manure (PSTF+OF) significantly increased soil dehydrogenase and catalase activity.Therefore,long-term application of chemical fertilizer with organic fertilizer can effectively improve soil fertility. 展开更多
关键词 long-term fertilization Paddy field UPLAND Microbial community STRUCTURE SOIL enzyme ACTIVITY
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The mechanisms underlying long-term potentiation of C-fiber evoked field potentials in spinal dorsal horn 被引量:7
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作者 LIU Xian-Guo 《生理学报》 CAS CSCD 北大核心 2008年第5期653-663,共11页
Long-term potentiation(LTP) of C-fiber evoked field potentials in spinal dorsal horn is first reported in 1995.Since then,the mechanisms underlying the long-lasting enhancement in synaptic transmission between primary... Long-term potentiation(LTP) of C-fiber evoked field potentials in spinal dorsal horn is first reported in 1995.Since then,the mechanisms underlying the long-lasting enhancement in synaptic transmission between primary afferent C-fibers and neurons in spinal dorsal horn have been investigated by different laboratories.In this article,the related data were summarized and discussed. 展开更多
关键词 脊髓 电位 临床分析 神经纤维
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Effects of electric field treatment on microstructures of GH4199 superalloy after long-term aging 被引量:2
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作者 刘杨 王磊 +2 位作者 王帅 乔雪璎 王延庆 《中国有色金属学会会刊:英文版》 CSCD 2006年第A03期1953-1957,共5页
The effects of electric field intensity and treatment temperature on the microstructures of GH4199 superalloy after long-term aging were investigated. The results show that the number and size of carbides and TCP(σph... The effects of electric field intensity and treatment temperature on the microstructures of GH4199 superalloy after long-term aging were investigated. The results show that the number and size of carbides and TCP(σphase andμphase) phase in the alloy increase with increasing electric field intensity at the same heat treatment temperature and holding time. While the number and size of carbides and TCP phase are weekly influenced by treatment temperature with lower electric field intensity of 2 kV/cm. When the treat temperature is up to 1 093 K, annealing twins appear in the alloy, and the number of twins increases with increasing holding time. Since the electric field can provide the enough energy for the movement of vacancies and atom, it is considered that the nucleus of the twins formed with formation stack faults due to the mismatch of local atom in crystal caused by the vacancies, and the twins will grow with the increase of holding time. Meanwhile, such promoting effects on atom movement of the electric field increase with the increase of the electric field intensity, meantime the carbides and TCP phase grow fast with the increase of electric field intensity. 展开更多
关键词 电场 高温合金 时效分析 微观结构
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Electric stimulation at sciatic nerve evokes long-term potentiation of cornu dorsale medullae spinalis field potential in rats at various developmental phases 被引量:1
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作者 Jiang Wu Dan Shu Qisheng Hu 《Neural Regeneration Research》 SCIE CAS CSCD 2007年第7期385-389,共5页
BACKGROUND: Long-term potentiation of cornu dorsale medullae spinalis field potential in adult rats has already been reported; however, there is lack of correlated researches on naenonate, infant and adult rats which... BACKGROUND: Long-term potentiation of cornu dorsale medullae spinalis field potential in adult rats has already been reported; however, there is lack of correlated researches on naenonate, infant and adult rats which have different responses to pain conduction information.OBJECTIVE: To observe the various effects of electric stimulation at sciatic nerve on long-term potentiation of evoked field potential at superficial layer of cornu dorsale medullae spinalis of rats at various developmental phases and analyze manifestations of pain conduction information at superficial layers ( Ⅰ - Ⅱ)of cornu dorsale medullae spinalis in immature rats.DESIGN: Grouping controlled study.SETTING: Department of Physiology, Medical College of Wuhan University.MATERIALS: The experiment was carried out in the Laboratory of Physiology (provincial laboratory),Medical College of Wuhan University from March 2006 to May 2007. A total of 27 healthy male Sprague-Dawley (SD) rats, 17- 90 days old, SPF grade, weighing 41 -200 g, were provided by Experimental Animal Center, Medical College of Wuhan University.METHODS: Based on their birthdays, rats were divided into naenonate group (17 - 20 days old, weighing 41-52 g, n =10), infant group (35 - 50 days old, weighing 87 - 125 g, n =10) and adult group (60 - 90 days old, weighing 180 -200 g, n =7). Left sciatic nerve was separated and stimulated with single square wave (15 V, 0.5 ms). Meanwhile, evoked field potential was recorded at superficial layers of lateral T13 - L1 cornu dorsale medullae spinalis and then stimulated with high-frequent and high-intensive tetanizing current (30 -40 V, 0.5 ms, 100 Hz, 1s per bundle, 10s in bundle interval) four times. After the operation, onset of long-term potentiation was observed; meanwhile, amplitude changes and latency of field potential were analyzed.MAIN OUTCOME MEASURES: Amplitude and latency changes of field potential at superficial layers of cornu dorsale medullae spinalis of rats in the three groups.RESULTS: A total of 27 accepted rats were involved in the final analysis. ① Amplitude changes: Electric stimulation at sciatic nerve with high-frequent and high-intensive tetanizing current could induce evoked field potential at superficial layers (Ⅰ-Ⅱ ) of cornu dorsale medullae spinalis in the three groups.Long-term potentiation in the naenonate group manifested that amplitude of A-kind never fiber was raised and there was significant difference (P〈0.05). In addition, average amplitude was increased and there was obviously significant difference (P〈0.01). Long-term potentiation in the infant group manifested that amplitude of C-kind never fiber was raised and there was significant difference (P〈0.01); while, long-term potentiation in the adult group manifested that amplitude of C-kind never fiber was raised and there was significant difference (P〈0.01). Otherwise, latencies in the three groups were all shortened. ② Latency changes: Average latency of A-kind nerve fiber in the naenonate group was shortened and there was significant difference (P〈0.01); in addition, evoked potential of C-kind nerve fiber was low and latency was immovable. There was no significant difference before and after high-frequent and high-intensive electric stimulation (P〉0.05). Average latency of C-kind nerve fiber in the infant group was shortened and there was significant difference (P〈0.01); in addition, evoked potential of A-kind nerve fiber was stable and latency was immovable. There was no significant difference before and after high-frequent and high-intensive electric stimulation (P〉0.05). Average latency of C-kind nerve fiber in the adult group was shortened and there was significant difference (P〈0.01); in addition, evoked potential of A-kind nerve fiber was stable and latency was immovable. There was no significant difference before and after high-frequent and high-intensive electric stimulation.CONCLUSION: Evoked field potential at superficial layer of comu dorsale medullae spinalis can be recorded through electric stimulation at sciatic nerve. Single stimulation and tetanizing electric stimulation can cause different characteristics of evoked field potential in rats at various developmental phases.Superficial layer of cornu dorsale medullae spinalis of naenonate rats is mainly caused by A-kind nerve fiber which participants in pain conduction and formation of pain sensitivity; however, that of infant and adult rats mainly depends on C-kind nerve fiber. 展开更多
关键词 long-term potentiation spinal cord electric stimulation
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Assessment of Long-Term Compost Application on Physical, Chemical, and Biological Properties, as Well as Fertility, of Soil in a Field Subjected to Double Cropping 被引量:5
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作者 Yukiko Yanagi Haruo Shindo 《Agricultural Sciences》 2016年第1期30-43,共14页
The aim of this article was to assess the influence of long-term application of compost on the physical, chemical, and biological properties, as well as the fertility, of soil in a field subjected to double cropping (... The aim of this article was to assess the influence of long-term application of compost on the physical, chemical, and biological properties, as well as the fertility, of soil in a field subjected to double cropping (paddy rice and barley), mainly by integrating previous studies of the effects of compost and manure on soil qualities. Continuous compost application, especially at a high level (30 Mg·ha<sup>-1</sup>·y<sup>-1</sup>), into the double cropping soils increased the activities of organic C-, N-, and P-decomposing enzymes and the contents of organic C, total N, and microbial biomass N, as well as the cation exchange capacity, thereby contributing to the enhancement of soil fertility. Also, the compost application increased the degree of water-stable soil macroaggregation (>0.25 mm), which was correlated significantly (r > 0.950, p < 0.05) with the contents of hydrolyzable carbohydrates (with negative charge) and active Al (with positive charge), and resulted in the modification of soil physical properties. Furthermore, the application increased the amount of soil organic matter, including humic acid with a low degree of darkening and fulvic acid, and contributed to C sequestration and storage. Physical fractionation of soil indicated that about 60% of soil organic C was distributed in the silt-sized (2 - 20 μm) aggregate and clay-sized (<2 μm) aggregate fractions, while about 30% existed in the decayed plant fractions (53 - 2000 μm). The results obtained unambiguously indicate that long-term application of compost can improve soil qualities in the field subjected to double cropping, depending on the amount applied. 展开更多
关键词 Beneficial Effect Double Cropping Soil long-term Compost Application Soil Quality
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Long-term field measurement and analysis of the natural wind characteristics at the site of Xi-hou-men Bridge 被引量:2
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作者 Ming LIU Hai-li LIAO +2 位作者 Ming-shui LI Cun-ming MA Mei YU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2012年第3期197-207,共11页
In order to investigate the wind characteristics of coastal areas of China, a long-term field measurement of natural wind was carried out. Based on the field measurement results, this paper presents the natural wind c... In order to investigate the wind characteristics of coastal areas of China, a long-term field measurement of natural wind was carried out. Based on the field measurement results, this paper presents the natural wind characteristics of typhoons and strong monsoons at the site of Xi-hou-men Bridge, including mean wind speed, mean wind direction, mean wind elevation angle, turbulent intensity, gust factor, turbulence integral length scales, power spectrum of wind speed and spatial correlation of gusty wind, the profiles of mean wind speed and turbulent intensity, etc. The correlation among wind characteristics is analyzed in detail, and the similarities and differences of wind characteristics between typhoons and monsoons are analyzed. These results can pro- vide detailed wind characteristics of coastal areas of China. 展开更多
关键词 Wind characteristics field measurement Wind spectrum Wind profiles Spatial correlation
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Spatio-temporal variations of shallow seismic velocity changes in Salton Sea Geothermal Field,California in response to large regional earthquakes and long-term geothermal activities 被引量:1
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作者 Chengyuan Zhang Zhigang Peng +1 位作者 Xiaoyan Liu Chenyu Li 《Earthquake Research Advances》 CSCD 2023年第2期15-23,共9页
We measure spatio-temporal variations of seismic velocity changes in Salton Sea Geothermal Field,California based on cross correlations of daily seismic traces recorded by a borehole seismic network from December 2007... We measure spatio-temporal variations of seismic velocity changes in Salton Sea Geothermal Field,California based on cross correlations of daily seismic traces recorded by a borehole seismic network from December 2007 to January 2014.We find clear co-seismic velocity reductions during the 2010 M 7.2 El Mayor–Cucapah,Mexico earthquake at~100 km further south,followed by long-term recoveries.The co-seismic reductions are larger with longer post-seismic recoveries in higher frequency bands,indicating that material damage and healing process mostly occurred in the shallow depth.In addition,the co-seismic velocity reductions are larger for ray paths outside the active fluid injection/extraction regions.The ray paths inside injection/extraction regions are associated with smaller co-seismic reductions,but subtle long-term velocity increases.We also build 3D transient water flow models based on monthly injection/extraction rates,and find correlations between several water flow parameters and co-seismic velocity reductions.We interpret the relative lack of co-seismic velocity changes within the geothermal region as unclogging of fracture network due to persistent fluid flows of geothermal production.The long-term velocity increase is likely associated with the ground water depletion and subsidence due to net production. 展开更多
关键词 Seismic velocity changes Salton Sea Geothermal field Ambient noises Induced earthquakes Qinghai-Tibetan Plateau
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Clinical manifestations,diagnosis and long-term prognosis of adult autoimmune enteropathy:Experience from Peking Union Medical College Hospital 被引量:2
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作者 Mu-Han Li Ge-Chong Ruan +9 位作者 Wei-Xun Zhou Xiao-Qing Li Sheng-Yu Zhang Yang Chen Xiao-Yin Bai Hong Yang Yu-Jie Zhang Peng-Yu Zhao Ji Li Jing-Nan Li 《World Journal of Gastroenterology》 SCIE CAS 2024年第19期2523-2537,共15页
BACKGROUND Autoimmune enteropathy(AIE)is a rare disease whose diagnosis and long-term prognosis remain challenging,especially for adult AIE patients.AIM To improve overall understanding of this disease’s diagnosis an... BACKGROUND Autoimmune enteropathy(AIE)is a rare disease whose diagnosis and long-term prognosis remain challenging,especially for adult AIE patients.AIM To improve overall understanding of this disease’s diagnosis and prognosis.METHODS We retrospectively analyzed the clinical,endoscopic and histopathological characteristics and prognoses of 16 adult AIE patients in our tertiary medical center between 2011 and 2023,whose diagnosis was based on the 2007 diagnostic criteria.RESULTS Diarrhea in AIE patients was characterized by secretory diarrhea.The common endoscopic manifestations were edema,villous blunting and mucosal hyperemia in the duodenum and ileum.Villous blunting(100%),deep crypt lymphocytic infiltration(67%),apoptotic bodies(50%),and mild intraepithelial lymphocytosis(69%)were observed in the duodenal biopsies.Moreover,there were other remarkable abnormalities,including reduced or absent goblet cells(duodenum 94%,ileum 62%),reduced or absent Paneth cells(duodenum 94%,ileum 69%)and neutrophil infiltration(duodenum 100%,ileum 69%).Our patients also fulfilled the 2018 diagnostic criteria but did not match the 2022 diagnostic criteria due to undetectable anti-enterocyte antibodies.All patients received glucocorticoid therapy as the initial medication,of which 14/16 patients achieved a clinical response in 5(IQR:3-20)days.Immunosuppressants were administered to 9 patients with indications of steroid dependence(6/9),steroid refractory status(2/9),or intensified maintenance medication(1/9).During the median of 20.5 months of followup,2 patients died from multiple organ failure,and 1 was diagnosed with non-Hodgkin’s lymphoma.The cumulative relapse-free survival rates were 62.5%,55.6%and 37.0%at 6 months,12 months and 48 months,respectively.CONCLUSION Certain histopathological findings,including a decrease or disappearance of goblet and Paneth cells in intestinal biopsies,might be potential diagnostic criteria for adult AIE.The long-term prognosis is still unsatisfactory despite corticosteroid and immunosuppressant medications,which highlights the need for early diagnosis and novel medications. 展开更多
关键词 Autoimmune enteropathy Clinical manifestations Diagnostic criteria Pathological features long-term prognosis
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Drilling-based measuring method for the c-φ parameter of rock and its field application 被引量:3
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作者 Bei Jiang Fenglin Ma +5 位作者 Qi Wang Hongke Gao Dahu Zhai Yusong Deng Chuanjie Xu Liangdi Yao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第1期65-76,共12页
The technology of drilling tests makes it possible to obtain the strength parameter of rock accurately in situ. In this paper, a new rock cutting analysis model that considers the influence of the rock crushing zone(R... The technology of drilling tests makes it possible to obtain the strength parameter of rock accurately in situ. In this paper, a new rock cutting analysis model that considers the influence of the rock crushing zone(RCZ) is built. The formula for an ultimate cutting force is established based on the limit equilibrium principle. The relationship between digital drilling parameters(DDP) and the c-φ parameter(DDP-cφ formula, where c refers to the cohesion and φ refers to the internal friction angle) is derived, and the response of drilling parameters and cutting ratio to the strength parameters is analyzed. The drillingbased measuring method for the c-φ parameter of rock is constructed. The laboratory verification test is then completed, and the difference in results between the drilling test and the compression test is less than 6%. On this basis, in-situ rock drilling tests in a traffic tunnel and a coal mine roadway are carried out, and the strength parameters of the surrounding rock are effectively tested. The average difference ratio of the results is less than 11%, which verifies the effectiveness of the proposed method for obtaining the strength parameters based on digital drilling. This study provides methodological support for field testing of rock strength parameters. 展开更多
关键词 Digital drilling Rock crushing zone c-u parameter Measurement method field application
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Long-term and inter-annual mass changes of Patagonia Ice Field from GRACE
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作者 Jin Li Jianli Chen +2 位作者 Shengnan Ni Lu Tang Xiaogong Hu 《Geodesy and Geodynamics》 2019年第2期100-109,共10页
Using more than 14 years of GRACE(Gravity Recovery and Climate Experiment) satellite gravimetry observations, we estimate the ice loss rate for the Patagonia Ice Field(PIF) of South America. After correcting the effec... Using more than 14 years of GRACE(Gravity Recovery and Climate Experiment) satellite gravimetry observations, we estimate the ice loss rate for the Patagonia Ice Field(PIF) of South America. After correcting the effects of glacier isostatic adjustment(GIA) and hydrological variations, the ice loss rate is -23.5 ± 8.1 Giga ton per year(Gt/yr) during the period April 2002 through December 2016, equivalent to an average ice thickness change of-1.3 m/yr if evenly distributed over PIF. The PIF ice mass change series also show obvious inter-annual variations during the entire period. For the time spans April 2002 to December 2007, January 2008 to December 2012 and January 2013 to December 2016, the ice loss rates are -26.4,-9.0 and -25.0 Gt/yr, respectively, indicating that the ice melting experienced significant slowing down and accelerating again in the past decade. Comparison with time series from temperature and precipitation data over PIF suggests that the inter-annual ice losses might not be directly correlated with the temperature changes and precipitation anomalies, and thus their interrelation is intricate. However, the dramatic ice loss acceleration in 2016(with more than 100 Gt within the first half of the year) appears closely related with the evident temperature increase and severe precipitation shortage over 2016, which are likely correlated with the strong E1 Nino event around 2016. Moreover, we compare the GRACE spherical harmonic(SH) and mass concentration(Mascon) solutions in estimating the PIF ice loss rate, and find that the Mascon result has larger uncertainty in leakage error correction,while the SH solutions can better correct leakage errors based on a constrained forward modeling iterative method. Thus the GRACE SH solutions with constrained forward modeling recovery are recommended to evaluating the ice mass change of PIF or other glacier regions with relatively smaller spatial scales. 展开更多
关键词 GRACE SPHERICAL HARMONIC SOLUTION Mascon SOLUTION PATAGONIA Ice field INTER-ANNUAL mass change
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Strong coupling and catenary field enhancement in the hybrid plasmonic metamaterial cavity and TMDC monolayers 被引量:2
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作者 Andergachew Mekonnen Berhe Khalil As’ham +2 位作者 Ibrahim Al-Ani Haroldo T.Hattori Andrey E.Miroshnichenko 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第5期20-32,共13页
Strong coupling between resonantly matched surface plasmons of metals and excitons of quantum emitters results in the formation of new plasmon-exciton hybridized energy states.In plasmon-exciton strong coupling,plasmo... Strong coupling between resonantly matched surface plasmons of metals and excitons of quantum emitters results in the formation of new plasmon-exciton hybridized energy states.In plasmon-exciton strong coupling,plasmonic nanocavities play a significant role due to their ability to confine light in an ultrasmall volume.Additionally,two-dimensional transition metal dichalcogenides(TMDCs) have a significant exciton binding energy and remain stable at ambient conditions,making them an excellent alternative for investigating light-matter interactions.As a result,strong plasmon-exciton coupling has been reported by introducing a single metallic cavity.However,single nanoparticles have lower spatial confinement of electromagnetic fields and limited tunability to match the excitonic resonance.Here,we introduce the concept of catenary-shaped optical fields induced by plasmonic metamaterial cavities to scale the strength of plasmon-exciton coupling.The demonstrated plasmon modes of metallic metamaterial cavities offer high confinement and tunability and can match with the excitons of TMDCs to exhibit a strong coupling regime by tuning either the size of the cavity gap or thickness.The calculated Rabi splitting of Au-MoSe_2 and Au-WSe_2 heterostructures strongly depends on the catenary-like field enhancement induced by the Au cavity,resulting in room-temperature Rabi splitting ranging between 77.86 and 320 me V.These plasmonic metamaterial cavities can pave the way for manipulating excitons in TMDCs and operating active nanophotonic devices at ambient temperature. 展开更多
关键词 catenary-shaped field enhancement strong coupling PLASMON EXCITON Rabi splitting
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Constructing Built-In Electric Fields with Semiconductor Junctions and Schottky Junctions Based on Mo-MXene/Mo-Metal Sulfides for Electromagnetic Response 被引量:3
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作者 Xiaojun Zeng Xiao Jiang +2 位作者 Ya Ning Yanfeng Gao Renchao Che 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第10期453-473,共21页
The exploration of novel multivariate heterostructures has emerged as a pivotal strategy for developing high-performance electromagnetic wave(EMW)absorption materials.However,the loss mechanism in traditional heterost... The exploration of novel multivariate heterostructures has emerged as a pivotal strategy for developing high-performance electromagnetic wave(EMW)absorption materials.However,the loss mechanism in traditional heterostructures is relatively simple,guided by empirical observations,and is not monotonous.In this work,we presented a novel semiconductor-semiconductor-metal heterostructure sys-tem,Mo-MXene/Mo-metal sulfides(metal=Sn,Fe,Mn,Co,Ni,Zn,and Cu),including semiconductor junctions and Mott-Schottky junctions.By skillfully combining these distinct functional components(Mo-MXene,MoS_(2),metal sulfides),we can engineer a multiple heterogeneous interface with superior absorption capabilities,broad effective absorption bandwidths,and ultrathin matching thickness.The successful establishment of semiconductor-semiconductor-metal heterostructures gives rise to a built-in electric field that intensifies electron transfer,as confirmed by density functional theory,which collaborates with multiple dielectric polarization mechanisms to substantially amplify EMW absorption.We detailed a successful synthesis of a series of Mo-MXene/Mo-metal sulfides featuring both semiconductor-semiconductor and semiconductor-metal interfaces.The achievements were most pronounced in Mo-MXene/Mo-Sn sulfide,which achieved remarkable reflection loss values of-70.6 dB at a matching thickness of only 1.885 mm.Radar cross-section calculations indicate that these MXene/Mo-metal sulfides have tremendous potential in practical military stealth technology.This work marks a departure from conventional component design limitations and presents a novel pathway for the creation of advanced MXene-based composites with potent EMW absorption capabilities. 展开更多
关键词 Semiconductor-semiconductor-metal heterostructure Semiconductor junctions Mott-Schottky junctions Built-in electric field Electromagnetic wave absorption
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Development of a new Cox model for predicting long-term survival in hepatitis cirrhosis patients underwent transjugular intrahepatic portosystemic shunts 被引量:1
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作者 Yi-Fan Lv Bing Zhu +8 位作者 Ming-Ming Meng Yi-Fan Wu Cheng-Bin Dong Yu Zhang Bo-Wen Liu Shao-Li You Sa Lv Yong-Ping Yang Fu-Quan Liu 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第2期491-502,共12页
BACKGROUND Transjugular intrahepatic portosystemic shunt(TIPS)placement is a procedure that can effectively treat complications of portal hypertension,such as variceal bleeding and refractory ascites.However,there hav... BACKGROUND Transjugular intrahepatic portosystemic shunt(TIPS)placement is a procedure that can effectively treat complications of portal hypertension,such as variceal bleeding and refractory ascites.However,there have been no specific studies on predicting long-term survival after TIPS placement.AIM To establish a model to predict long-term survival in patients with hepatitis cirrhosis after TIPS.METHODS A retrospective analysis was conducted on a cohort of 224 patients who un-derwent TIPS implantation.Through univariate and multivariate Cox regression analyses,various factors were examined for their ability to predict survival at 6 years after TIPS.Consequently,a composite score was formulated,encompassing the indication,shunt reasonability,portal venous pressure gradient(PPG)after TIPS,percentage decrease in portal venous pressure(PVP),indocyanine green retention rate at 15 min(ICGR15)and total bilirubin(Tbil)level.Furthermore,the performance of the newly developed Cox(NDC)model was evaluated in an in-ternal validation cohort and compared with that of a series of existing models.RESULTS The indication(variceal bleeding or ascites),shunt reasonability(reasonable or unreasonable),ICGR15,post-operative PPG,percentage of PVP decrease and Tbil were found to be independent factors affecting long-term survival after TIPS placement.The NDC model incorporated these parameters and successfully identified patients at high risk,exhibiting a notably elevated mortality rate following the TIPS procedure,as observed in both the training and validation cohorts.Additionally,in terms of predicting the long-term survival rate,the performance of the NDC model was significantly better than that of the other four models[Child-Pugh,model for end-stage liver disease(MELD),MELD-sodium and the Freiburg index of post-TIPS survival].CONCLUSION The NDC model can accurately predict long-term survival after the TIPS procedure in patients with hepatitis cirrhosis,help identify high-risk patients and guide follow-up management after TIPS implantation. 展开更多
关键词 Transjugular intrahepatic portosystemic shunt long-term survival Predictive model
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Magnetic Field Configurations Corresponding to Electric Field Patterns That Evoke Long-Term Potentiation Shift Power Spectra of Light Emissions from Microtubules from Non-Neural Cells
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作者 Blake T. Dotta David A.E. Vares +2 位作者 Carly A. Buckner Robert M. Lafrenie Michael A. Persinger 《Open Journal of Biophysics》 2014年第4期112-118,共7页
Photon counts were measured every 15 ms for 75 s from microtubule-enriched preparations (and nuclei) from mouse melanoma cells during baseline and after 2 min exposures to 1 μT magnetic fields. The magnetic fields we... Photon counts were measured every 15 ms for 75 s from microtubule-enriched preparations (and nuclei) from mouse melanoma cells during baseline and after 2 min exposures to 1 μT magnetic fields. The magnetic fields were generated from a circular array of solenoids and presented with accelerating or decelerating rotation velocities. The range of photon radiant flux density was in the order of 10-12 W·m-2. Microtubules preparations that had been exposed for only 2 min to a magnetic field configuration corresponding to the electric field pattern that induced long-term potentiation in neural tissue when applied as electric current displayed peaks of spectral power densities within 7 - 8 Hz, 9.5 Hz, 14 - 15 Hz, and 22 Hz bands. The major peak (9.4 Hz) bandwidth was approximately 0.1 Hz. While microtubule preparations exposed for 2 min to a 7 Hz sine-wave or in the absence of a field emitted an overall similar level of spectral power density, the peaks in power density were not present. Treatment with the LTP patterned fields, compared to the baseline or sine-wave fields primarily altered the frequency band in which the amplitude of the photon field was expressed. These results suggest that the photon emissions from microtubule preparations have the capacity to respond to specifically-patterned or geometric shapes of magnetic fields by altering spectral configurations rather than the absolute numbers of photons. 展开更多
关键词 MICROTUBULES PHOTON Emissions Spectral Density SHIFTS Physiologically-Patterned Magnetic fields
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ST-LSTM-SA:A New Ocean Sound Velocity Field Prediction Model Based on Deep Learning 被引量:1
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作者 Hanxiao YUAN Yang LIU +3 位作者 Qiuhua TANG Jie LI Guanxu CHEN Wuxu CAI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第7期1364-1378,共15页
The scarcity of in-situ ocean observations poses a challenge for real-time information acquisition in the ocean.Among the crucial hydroacoustic environmental parameters,ocean sound velocity exhibits significant spatia... The scarcity of in-situ ocean observations poses a challenge for real-time information acquisition in the ocean.Among the crucial hydroacoustic environmental parameters,ocean sound velocity exhibits significant spatial and temporal variability and it is highly relevant to oceanic research.In this study,we propose a new data-driven approach,leveraging deep learning techniques,for the prediction of sound velocity fields(SVFs).Our novel spatiotemporal prediction model,STLSTM-SA,combines Spatiotemporal Long Short-Term Memory(ST-LSTM) with a self-attention mechanism to enable accurate and real-time prediction of SVFs.To circumvent the limited amount of observational data,we employ transfer learning by first training the model using reanalysis datasets,followed by fine-tuning it using in-situ analysis data to obtain the final prediction model.By utilizing the historical 12-month SVFs as input,our model predicts the SVFs for the subsequent three months.We compare the performance of five models:Artificial Neural Networks(ANN),Long ShortTerm Memory(LSTM),Convolutional LSTM(ConvLSTM),ST-LSTM,and our proposed ST-LSTM-SA model in a test experiment spanning 2019 to 2022.Our results demonstrate that the ST-LSTM-SA model significantly improves the prediction accuracy and stability of sound velocity in both temporal and spatial dimensions.The ST-LSTM-SA model not only accurately predicts the ocean sound velocity field(SVF),but also provides valuable insights for spatiotemporal prediction of other oceanic environmental variables. 展开更多
关键词 sound velocity field spatiotemporal prediction deep learning self-allention
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