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Role of flood discharge in shaping stream geometry:Analysis of a small modern stream in the Uinta Basin,USA

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Journal of Palaeogeography 2017年第1期6卷 84-95页

作者： Guang-Ming Hu Ru-Xin Ding Yan-Bing Li Jing-Fu Shan xiao-Tao Yu Wei feng School of Geosciences Yangtze UniversityWuhan 430100HubeiChina State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing 102249China School of Earth Science and Geological Engineering Sun Yat-sen UniversityGuangzhou 510275GuangdongChina Guangdong Provincial Key Laboratory of Mineral Resources and Geological Processes Guangzhou 510275GuangdongChina The Third Production Plant Daqing Oilfield BranchPetroChinaDaqing 163000HeilongjiangChina

This small modern river system is located on a retativety flat （about 1°-2°）, unconsotidated sandy pediment surface in the Uinta Basin of Utah, USA, and it is with a scare of about 30 m tong and 0.4-0.8 m wide, simitar as a natural flume experiment modet. The smart stream is informatty divided into upstream, midstream and downstream. The anatysis shows that flood discharge influences channet sinuosity and morphology to produce an initiat meandering pattern which is tater changed to a braided and then a straisht pattern in the downflow direction. The upstream segment has a hish sinuous geometry dominated by both erosion （cutbanks） and deposition （point bars）. In the resistance of sporadic vegetation rooting in banks, the upstream flood deviates its original direction, which resutts in the powerful flood intensively eroding the cutbank and accreting clastics to build point bars, and thus producing a high sinuous channet. The midstream is dominated by deposits （many smart bars） with a moderate to tow sinuosity. Due to the bad drainage of the high sinuous channel in the upstream, the strong flood can cut off the point bar comptetely or even surmount the tevee in the fast meandering upstream, which widens the channel suddenty with a quick decreasing current power. Then, the ctastics from the upstream are untoaded in the midstream and form many smart bars. Untoaded sediments protect the bank, and the tow-power current brings a moderate erosion to the bank, which forms a moderate to tow sinuous channel in the midstream. The downstream shows multistage erosionat terraces in its retativety straight channets. After the midstream water drops its toad, it becomes ＂dear＂ and reaches downstream, the tower current power is hetptess to reform channet 8eometry. Thus, the downstream channel sesment keeps a tower sinuous geometry, evenstraight partially. Small amounts of fine clastics are deposited, and simultaneously multistage terraces are formed due to regressive flood erosion.

关键词： Sinuosity Braiding Point bar Channel bar Flood discharge Uinta Basin

Evaluation of Surface Air Temperature Change over China and the Globe during the Twentieth Century in IAP AGCM4.0

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Atmospheric and Oceanic Science Letters 2012年第5期5卷 435-438页

作者： DONG xiao XUE feng ZHANG He ZENG Qing-Cun International Center for Climate and Environment Sciences Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

Based on time series and linear trend analysis, the authors evaluated the performance of the fourth gen- eration atmospheric general circulation model developed at the Institute of Atmospheric Physics, Chinese Academy of Sciences （IAP AGCM4.0）, in simulating surface air temperature （SAT） during the twentieth century over China and the globe. The numerical experiment is con- ducted by driving the model with the observed sea surface temperature and sea ice. It is shown that IAP AGCM4.0 can simulate the warming trend of the global SAT, with the major wanning regions in the high latitudes of the Northern Hemisphere and the mid-latitudes of the South- ern Hemisphere. While the simulated trend over the whole globe is close to the observation, the model trader- estimates the observed trend over the continents. More- over, the model simulates the spatial distribution of SAT in China, with a bias of approximately -2℃ in eastern China, but with a more serious bias in western China. Compared with the global mean, however, the correlation coefficient between the simulation and observation in China is significantly lower, indicating that there is large uncertainty in simulating regional climate change.

关键词： IAP AGCM4.0 surface air temperature thetwentieth century globe China

Treating aplasia cutis congenita in a newborn with the combination of ionic silver dressing and moist exposed burn ointment: A case report

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World Journal of Clinical Cases 2019年第17期7卷 2611-2616页

作者： Guo-feng Lei Jun-Ping Zhang xiao-Bing Wang xiao-Li You Jin-Ya Gao xiao-Mei Li Mei-Ling Chen Xiu-Qin Ning Jiang-Li Sun Department of Neonatal Intensive Care Unit Sanmenxia Central HospitalSanmenxia 472000Henan ProvinceChina Department of Intensive Care Unit Sanmenxia Central HospitalSanmenxia 472000Henan ProvinceChina Reproductive endocrine center Sanmenxia Central HospitalSanmenxia 472000Henan ProvinceChina

BACKGROUND Aplasia cutis congenita (ACC) in newborns is a condition in which congenital defects or hypoplasia is present in part of the epidermis,dermis and even subcutaneous tissue (including muscle and bones).First reported by Cordon in 1767,ACC is a rare disease with a low incidence of 1/100000 to 3/***,there are 500 cases reported *** can be accompanied by other *** onset mechanism of the disease remains unknown but is thought to be correlated to factors such as genetics,narrow uterus,foetal skin and amniotic membrane adhesion,use of teratogenic drugs in early pregnancy and viral *** SUMMARY In August 2018,we treated a newborn with ACC on the left lower limbs using a combination of ionic silver dressing and moist exposed burn ointment (MEBO) and achieved a satisfactory treatment *** skin defects were observed on the external genitals and on areas from the left foot to 3/4 of the upper left *** tissue and blood vessels were observed in the regions with skin *** following treatments were ***,the wound was rinsed with 0.9% sodium chloride solution followed by disinfection with povidone-iodine *** then MEBO was applied to the wound at a thickness of approximately 1 *** applying ionic silver dressing,the wound was covered with sterile *** wound dressing was replaced every 2-3 *** the 4-mo follow-up,the treatment outcome was *** was minimal scar tissue formation,and limb function was not *** The combination of ionic silver dressing and MEBO to ACC is helpful.

关键词： Aplasia cutis congenita Newborns Ionic silver dressing Moist exposed burn ointment

Formation of Hearth Sediment during Vanadium Titano-magnetite Smelting in Blast Furnace No.7 of Chengde Iron and Steel Company

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Journal of Iron and Steel Research International 2015年第11期22卷 1009-1014页

作者： xiao-jie LIU Qing Lü Shu-jun CHEN Zhen-feng ZHANG Shu-hui ZHANG Yan-qin SUN School of Materials and Metallurgy Northeastern University College of Metallurgy and Energy Hebei Key Laboratory for Advanced Metallurgy Technology North China University of Science and Technology Chengde Branch Hebei Iron and Steel Group Co. Ltd.

The large quantity of sediment produced in the hearth during vanadium titano-magnetite smelting in a blast furnace（BF） affects the stability of the blast furnace operation. Testing and analysis of the sediment in the hearth of Chengde Iron and Steel Company？s BF No.7 revealed that it was mainly concentrated in the location below the tuyere and above the iron notch. Notably, some of the bonding material（sediment） consisted of greater than 50% pig iron, and the pig iron distributed in the slag was granular. It is proposed that a large quantity of Ti C and Ti（C,N） are deposited on the surface of the pig iron. These high melting point materials mix with iron drops, preventing the slag from flowing freely, thus leading to the formation of bonding materials. In addition, the viscosity and melting temperature of the slag in the tuyere areas fluctuate greatly, and thus the properties of the slag are unstable. Moreover, the slag contains large quantities of carbon, which results in the reduction of Ti O2. The resultant precipitation of Ti is followed by the formation of Ti C in the slag, which also leads to an increase in the viscosity of the slag and difficulty in achieving separation of the slag-iron. In fact, all of these factors interact with each other, and as a result, sediment is formed when the operating conditions in the hearth fluctuate.

关键词： vanadium titano-magnetite hearth sediment slag pig iron Ti(N C)

Sap Flow of Populus euphratica in a Desert Riparian Forest in an Extreme Arid Region During the Growing Season

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Journal of Integrative Plant Biology 2007年第4期49卷 425-436页

作者： Jian-Hua Si Qi feng xiao-You Zhang Zong-Qiang Chang Yong-Hong Su Hai-Yang Xi Cold and Arid Region Environmental and Engineering Research Institute the Chinese Academy of Sciences Alashan Desert Eco-hydrology Experimental Research Station Lanzhou 730000 China

In the present study, the heat pulse technique was applied to investigate the stem sap flow of Populus euphratica in a desert riparian forest in an extreme arid region from April to October 2003 and from May to October 2004. The experimental sites were in Qidaoqiao （101 °10′ E, 41°59′ N） and Bayantaolai farm （101°14′ E, 42°01′ N） in Ejina county, in the low reaches of the Heihe River, China. The results indicated that the diurnal change in the velocity of sap flow showed minor fluctuations. At night, the rising of sap flow could be observed in the main tree species because of root pressure. During the growing season, the maximum average velocity was observed in July, followed by August, and the same velocity was observed in September and May; the minimum velocity was observed in October. The transpiration from June to August during the growing season accounted for approximately 70% of the annual total transpiration. The sap flow velocity of P. euphratica trees of different ages could be arranged in the order： 15 yr 〉 25 yr 〉 50 yr. Sap flow velocity was closely related to changes in micrometeorological factors, with average sap flow velocity showing a significant linear correlation with net radiation, air temperature and relative humidity.

关键词： desert riparian forest extreme arid region heat-pulse technique Populus euphratica sap flow velocity.

以脑鸣为主要症状的头颈部静脉狭窄CT静脉成像分型研究

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中华神经外科杂志 2024年第8期40卷 810-814页

作者：董健任海燕朱广通毛贝贝关峰黄辉肖智勇胡志强吉训明首都医科大学附属北京世纪坛医院放射科北京100038 首都医科大学附属北京世纪坛医院神经外科北京100038 首都医科大学脑重大疾病研究中心北京脑重大疾病研究院北京100069 首都医科大学附属北京天坛医院放射科北京100070

目的探讨以脑鸣为主要症状的头颈部静脉狭窄的CT静脉成像(CTV)分型特点及不同分型患者部分临床资料的差异。方法2020年9月至2022年12月首都医科大学附属北京世纪坛医院基于CTV确诊43例头颈部静脉狭窄患者,患者均以脑鸣为主要症状。根据... 详细信息

目的探讨以脑鸣为主要症状的头颈部静脉狭窄的CT静脉成像(CTV)分型特点及不同分型患者部分临床资料的差异。方法2020年9月至2022年12月首都医科大学附属北京世纪坛医院基于CTV确诊43例头颈部静脉狭窄患者,患者均以脑鸣为主要症状。根据CTV表现将头颈部静脉狭窄分为颅内静脉窦型、颈内静脉型和复合型(同时存在颅内静脉窦和颈内静脉狭窄),回顾性分析3种分型患者的影像学特点及部分临床资料的差异。结果43例患者中,颅内静脉窦型14例(32.6%),其中10例狭窄位于横窦,为蛛网膜颗粒增生压迫所致;4例为窦汇与横窦移行部的线性狭窄。颈内静脉型16例(37.2%),狭窄均位于寰椎横突节段,其中6例为寰椎横突增生压迫狭窄,10例为颈内静脉走行于寰椎横突与茎突夹角之间,导致局部管腔受压狭窄。复合型13例(30.2%),狭窄位于横窦和寰椎横突节段,其中3例为窦汇与横窦移行部狭窄,10例为蛛网膜颗粒增生压迫横窦;有3例患者单侧颅内静脉窦及颈内静脉全程细小。颅内静脉窦型的女性患者占比高于颈内静脉型和复合型,而病程短于颈内静脉型和复合型,差异均有统计学意义(均P0.05)。结论基于CTV显示,以脑鸣为主要症状的头颈部静脉狭窄的3种分型构成比接近,其中蛛网膜颗粒压迫是颅内静脉窦型狭窄的常见原因;骨质增生压迫是颈内静脉型的常见原因;部分患者的静脉狭窄可能与先天发育因素有关。3种分型的头颈部静脉狭窄患者的临床特点可能存在差异。

关键词：颈静脉颅内静脉窦 CT静脉成像狭窄脑鸣分型

Improvement of the Focusing Resolution of Photonic Crystal Negative Refraction Imaging with a Hollow Component Structure

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Chinese Physics Letters 2013年第5期30卷 70-74页

作者： CHEN shou-Xiang YANG Xiu-Lun MENG Xiang-feng DONG Guo-Yan WANG Yu-Rong WANG Lin-Hui HUANG Zhe Department of Optics Shandong UniversityJinan 250100 Department of Materials Science and Engineering Tsinghua UniversityBeijing 100084

The negative refraction and imaging effects in photonic crystals can be used to solve diffraction limit problem in near-field *** transmission efficiency and image resolution is a critical work for negative refraction *** theoretically investigate the band structures,equi-frequency surfaces,electromagnetic wave propagation,and the image intensity distributions in a two-dimensional hexagonal photonic crystal consisting of hollow *** is found that,in contrast to a hexagonal photonic crystal consisting of solid dielectric cylinders of the same radius,photonic crystals with hollow components can be used to optimize the all-angle negative *** simulations show that the transmission efficiency and resolution of image can be enhanced by changing the radii of the hollow air rods.

关键词： refraction hexagonal resolution

Pay more attention to the immunologically comparative evaluation of HIV-1 DNA vaccine in combination with adjuvant cytokines： a long way to go

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Chinese Medical Journal 2006年第18期119卷 1583-1584页

作者： REN xiao-feng Department of Preventive Veterinary Medicine College of Veterinary Medicine Northeast Agricultural University Harbin 150030 China

To the Editor： A recent article entitled ＂HIV-1 DNA vaccine with adjuvant cytokines induces specific immune responses against HIV-1 infection in mice＂ was published in the Chinese Medical Journal. The authors descriptively analyzed the adjuvant potential of an interleukin-12 （IL-12）, interleukin-18 （IL-18）, regulated on activation of normal T-cell expressed and secreted factor （RANTES）, macrophage inflammatory protein 1 alpha （MIP-1α or stromal cell derived factor 1 （SDF-1） plasmid when coimmunized with an HIV Gag gene-based DNA vaccine. Consequently the authors believed that IL-12, IL-18, or SDF-1 plasmid DNA potentially serves as immune adjuvants in combination with therapeutic HIV-1 DNA vaccine. The RANTES, MIP-1α plasmid DNA potentially serves as Immune adjuvants in combination with HIV-1 prophylactic vaccine. Although the experiment allows us to consider such a coinoculation strategy as one of the means against HIV-1 infection, some special attentions should be highlighted.

关键词： IMMUNIZATION INFECTION MICE

Percutaneous liver biopsy： retrospective study of primary and secondary hepatic lymphoma in twenty-one patients

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Hepatobiliary & Pancreatic Diseases International 2017年第1期16卷 58-64页

作者： Yan-feng Bai Ji-Min Liu Xiu-Ming Zhang Chao-Zhe Jiang xiao Xu Shu-Sen Zheng Department of Pathology the First Affiliated Hospital Zhejiang University School of Medicine Hangzhou 310003 China Division of Hepatobiliary Pancreatic Surgery the First Affiliated Hospital Zhejiang University School of Medicine Hangzhou 310003 China Department of Pathology and Molecular Medicine Faculty of Health Sciences McMaster University Hamilton L8S 4K1 Canada

BACKGROUND： Hepatic lymphoma （HL） is categorized as primary and secondary hepatic lymphoma （PHL and SHL）. This disorder can present as hepatic mass or mass-like lesion. Chemotherapy often is the first line treatment for patients with HL. Thus, an accurate pre-management histological diagnosis is essential to potentially improve clinical outcomes. The present study was to explore the prevalence of HL in ultrasound guided liver biopsies for hepatic mass or mass-like lesions, to investigate HL associated clinicopathological features, to raise the awareness of early recognition and proper diagnosis of this entity, and to assess specimen adequacy in needle core biopsy. METHODS： Twenty-one cases of HL were enrolled. Clinical and pathological characteristics were evaluated, quality of biopsies was assessed and pertinent literature was reviewed. RESULTS： HL was diagnosed in 0.94% of 2242 liver biopsy cases with ambiguous clinical presentation, laboratory tests and image studies. There were two cases of PHL （0.09%）, and nineteen cases of SHL （0.85%）. Histopathologically, diffuse large B-cell lymphoma was the most common type, followed by B-cell lymphoma not otherwise specified, T-ceU lymphoma, Hodgkin＇s lymphoma, and B-cell chronic lymphocytic leukemia/small lymphocytic lymphoma. Additionally, three lym- phocytic infiltration patterns were documented microscopically. The nodular infiltration was the most common type. CONCLUSIONS： HL is a rare entity and histopathology along with ancillary tests remains the only way to make the ***＇ awareness of this entity and early liver biopsy are essential in patient management.

关键词： hepatic lymphoma primary and secondary percutaneous needle core biopsy