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A short review of malabsorption and anemia

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World Journal of Gastroenterology 2009年第37期15卷 4644-4652页

作者： Fernando Fernández-ba.a.es Helena Monzón Montserrat Forné Department of Gastroenterology Hospital Universitari Mutua Terrassa University of Barcelona Plaza Dr Robert 5 08221 Terrassa Barcelona Spain

Anemia is a frequent finding in most diseases which cause malabsorption. The most frequent etiology is the combination of iron and vitamin B12 deficiency. Celiac disease is frequently diagnosed in patients referred for evaluation of iron deficiency anemia (Ida), being reported in 1.8%-14.6% of patients. Therefore, duodenal biopsies should be taken during endoscopy if no obvious cause of iron defi ciency (ID) can be found. Coba.a.in defi ciency occurs frequently among elderly patients, but it is often unrecognized because the clinical manifestations are subtle; it is caused primarily by food-coba.a.in malabsorption and pernicious anemia. The classic treatment of coba.a.in deficiency has been parenteral administration of the vitamin. Recent data suggest that alternative routes of coba.a.in administration (oral and nasal) may be useful in some cases. Anemia is a frequent complication of gastrectomy, and has been often described after bariatric surgery. It has been shown that banding procedures which maintain digestive continuity with the antrum and duodenum are associated with low rates of ID. Helicobacter pylori (H pylori) infection may be considered as a risk factor for Ida, mainly in groups with high demands for iron, such as some children and adolescents. Further controlled trials are needed before making solid recommendations about H pylori eradication in these cases.

关键词： Anemia Celiac disease Helicobacter pylori Coba.a.in deficiency Gastrectomy

Trends of the precipitation acidity over China during 1992–2006

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Chinese Science Bulletin 2010年第17期55卷 1800-1807页

作者： TANG Jie XU XiaoBin ba Jin WANG ShuFeng Key Laboratory for Atmospheric Chemistry Centre for Atmosphere Watch and Services Chinese Academy of Meteorological Sciences China Meteorological Administration Beijing 100081 China

The trends of the precipitation acidity from 1992 to 2006 were studied, based on the long-term acid rain observations at 74 sites in China. The results show that there was no remarkable change or extension of acid rain area (i.e., with annual mean of precipitation pHcame more acidified in the 15 years, with more pronounced trends in North China and the north of Central China. A slight decrease in the precipitation acidity was found in Southwest China, an area characterized as severest acid rain area for about two decades after the early 1980s. Consequently, the center of severe acid rain area in the south of the Yangtze River moved eastwards. The non-hydrogen conductivity (NHC), which is defined as the difference between the measured precipitation conductivity and the H+ conductivity calculated from measured pH, was estimated and treated as a proxy of soluble ions in precipitation. The result shows that the overall trend of the NHC before 1999 was pronounced and positive, while the trend after 2000 was inconspicuous or slightly negative. During 2000–2006, the change rate of pH was positively correlated to that of the NHC at 21 sites, implying that the increa

关键词： China acid rain precipitation acidity trend

Training Neuro-Fuzzy by Using Meta-Heuristic Algorithms for MPPT

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Computer Systems Science & Engineering 2023年第4期45卷 69-84页

作者： Ceren baştemur Kaya Ebubekir Kaya Göksel Gökkuş Department of Computer Technologies Nevsehir Vocational CollegeNevsehir Haci Bektas Veli UniversityNevşehir50300Turkey Department of Computer Engineering Faculty of Engineering and ArchitectureNevsehir Haci Bektas Veli UniversityNevşehir50300Turkey Department of Electrical and Electronics Engineering Faculty of Engineering and ArchitectureNevsehir Haci Bektas Veli UniversityNevşehir50300Turkey

It is one of the topics that have been studied extensively on maximum power point tracking(MPPT)*** or soft computing methods are used for *** soft computing approaches are more effective than traditional approaches,studies on MPPT have shifted in this *** study aims comparison of performance of seven meta-heuristic training algorithms in the neuro-fuzzy training for *** meta-heuristic training algorithms used are particle swarm optimization(PSO),harmony search(HS),cuckoo search(CS),artificial bee colony(ABC)algorithm,bee algorithm(ba),differential evolution(DE)and flower pollination algorithm(FPA).The antecedent and conclusion parameters of neuro-fuzzy are determined by these *** data of a 250 W photovoltaic(PV)is used in the *** effective MPPT,different neuro-fuzzy structures,different membership functions and different control parameter values are evaluated in *** training algorithms are compared in terms of solution quality and convergence *** strengths and weaknesses of these algorithms are *** is seen that the type and number of membership function,colony size,number of generations affect the solution quality and convergence speed of the training *** a result,it has been observed that CS and ABC algorithm are more effective than other algorithms in terms of solution quality and convergence in solving the related problem.

关键词： Optimization meta-heuristic algorithm neuro-fuzzy MPPT photovoltaic system

High-gain and low-distortion Brillouin amplification based on pump multi-frequency intensity modulation

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Chinese Physics B 2019年第2期28卷 277-282页

作者： Li-Wen Sheng De-Xin ba Zhi-Wei Lv National Key Laboratory of Science and Technology on Tunable Laser Harbin Institute of Technology

Using a pump with a multi-line spectrum to broaden the Brillouin gain bandwidth is an effective way to achieve lowdistortion amplification with high gain. Here, we theoretically and experimentally investigate the generation of a broadband Brillouin gain spectrum based on multi-frequency intensity modulation in an optical fiber. The arbitrary bandwidth of the Brillouin gain spectrum of stimulated Brillouin scattering(SBS) can be obtained as expected. In our experiment, a broadband Brillouin gain spectrum with a bandwidth of about 200 MHz is demonstrated. We also achieve a low-distortion amplification of a weak signal, whose maximum magnification is 65 d B for a-68-dBm input power signal.

关键词： Brillouin gain spectrum bandwidth intensity modulation low distortion amplification

Effect of Pre-deformation on Grain Ultrafining by Intercritical Deformation in Low-carbon Microalloyed Steels

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Acta Metallurgica Sinica(English Letters) 2018年第10期31卷 1038-1048页

作者： ba Li Qing-You Liu Shu-Jun Jia Yi Ren Bing Wang Central Iron and Steel Research Institute Beijing 100081China Iron and Steel Research Institute Ansteel Group Co. Ltd.Anshan 114009 China

In this study, the effect of pre-deformation at recrystallization and non-recrystallization zone on the grain ultrafining by the subsequent intercritical deformation （ID） was investigated on low-carbon microalloyed steel. The results showed that ultrafine grain microstructure with an average size of - 1.0 μm was fabricated through pre-deformation in the recrys- tallization zone followed by ID. When pre-deformed at the non-recrystallization zone prior to ID, the grain size increased to 1.6 μm with a heterogeneous distribution along with the well-developed dynamic recovery of ferrite. The grain ultrafining mechanism was attributed to the combined action of the deformation-induced ferrite transformation and the continuous dynamic recrystallization. In particular, the continuous dynamic recrystallization process during ID occurred on the pro-eutectoid ferrite as a result of the subgrain rotation mechanism and the absorbing dislocations mechanism.

关键词： Low-carbon microalloyed steels Intercritical deformation Ultrafine grain Continuous dynamic recrystallization Deformation-induced ferrite transformation

Analysis of an Ar plasma jet in a dielectric barrier discharge conjugated with a microsecond pulse

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Plasma Science and Technology 2019年第9期21卷 73-81页

作者： Duc ba NGUYEN Quang Hung TRINH Won Gyu LEE Young Sun MOK Department of Chemical and Biological Engineering Jeju National University Jeju 63243 Republic of Korea Center for Advanced Chemistry Institute of Research and Development Duy Tan University 03 Quang Trung Da Nang Vietnam Division of Chemical Engineering and Bioengineering Kangwon National University Chuncheon Kangwon 24341 Republic of Korea

In this work, an Ar plasma jet generated by an AC-microsecond-pulse-driven dielectric barrier discharge reactor, which had two ring-shaped electrodes isolated from the ambient atmosphere by transformer oil, was investigated. By special design of the oil insulation, a chemically active Ar plasma jet along with a safe and stable plasma process as well as low emission of CO and NOxwere successfully achieved. The results indicated that applied voltage and frequency were basic factors influencing the jet temperature, discharge power, and jet length, which increased significantly with the two operating parameters. Meanwhile, gas velocity affected the jet temperature in a reverse direction. In comparison with a He plasma jet, the Ar plasma jet had relatively low jet temperature under the same level of the input parameters, being preferable for bio-applications. The Ar plasma jet has been tested to interact with human skin within 5 min without the perception of burnt skin and electrical shock.

关键词： Ar plasma jet atmospheric pressure plasma jet OES of Ar gas emission of Ar plasma jet transformer oil

Direction finding for two-dimensional incoherently distributed sources with Hadamard shift invariance in non-uniform orthogonal arrays

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Chinese Journal of Aeronautics 2018年第12期31卷 2260-2269页

作者： Zhengliang daI Weijia CUI daming WANG Bin ba Chao WANG Yankui ZHANG National Digital Switching System Engineering&Technological Research Center Zhengzhou 450001China

This paper proposes a novel algorithm for Two-Dimensional(2D) central Directionof-Arrival(DOA) estimation of incoherently distributed sources. In particular, an orthogonal array structure consisting of two Non-uniform Linear Arrays(NLAs) is considered. based on first-order Taylor series approximation, the Generalized Array Manifold(GAM) model can first be established to separate the central DOAs from the original array manifold. Then, the Hadamard rotational invariance relationships inside the GAMs of two NLAs are identified. With the aid of such relationships, the central elevation and azimuth DOAs can be estimated through a search-free polynomial rooting method. Additionally, a simple parameter pairing of the estimated 2D angular parameters is also accomplished via the Hadamard rotational invariance relationship inside the GAM of the whole array. A secondary but important result is a derivation of closed-form expressions of the Cramer-Rao lower bound. The simulation results show that the proposed algorithm can achieve a remarkably higher precision at less complexity increment compared with the existing low-complexity methods, which benefits from the larger array aperture of the NLAs. Moreover, it requires no priori information about the angular distributed function.

关键词： Array signal processing Cramer-Rao lower bound Direction-of-Arrival(DOA) estimation Hadamard rotational invariance Incoherently distributed sources Non-uniform orthogonal array

Force Control Compensation Method with Variable Load Stiffness and damping of the Hydraulic Drive Unit Force Control System

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Chinese Journal of Mechanical Engineering 2016年第3期29卷 454-464页

作者： KONG Xiangdong ba Kaixian YU Bin caO Yuan ZHU Qixin ZHAO Hualong National Engineering Research Center for Local Joint of Advanced Manufacturing Technology and Equipment Yanshan University School of Mechanical Engineering Yanshan University State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang University

Each joint of hydraulic drive quadruped robot is driven by the hydraulic drive unit（HDU）, and the contacting between the robot foot end and the ground is complex and variable, which increases the difficulty of force control inevitably. In the recent years, although many scholars researched some control methods such as disturbance rejection control, parameter self-adaptive control, impedance control and so on, to improve the force control performance of HDU, the robustness of the force control still needs improving. Therefore, how to simulate the complex and variable load characteristics of the environment structure and how to ensure HDU having excellent force control performance with the complex and variable load characteristics are key issues to be solved in this paper. The force control system mathematic model of HDU is established by the mechanism modeling method, and the theoretical models of a novel force control compensation method and a load characteristics simulation method under different environment structures are derived, considering the dynamic characteristics of the load stiffness and the load damping under different environment structures. Then, simulation effects of the variable load stiffness and load damping under the step and sinusoidal load force are analyzed experimentally on the HDU force control performance test platform, which provides the foundation for the force control compensation experiment research. In addition, the optimized PID control parameters are designed to make the HDU have better force control performance with suitable load stiffness and load damping, under which the force control compensation method is introduced, and the robustness of the force control system with several constant load characteristics and the variable load characteristics respectively are comparatively analyzed by experiment. The research results indicate that if the load characteristics are known, the force control compensation method presented in this paper

关键词： quadruped robot force control system hydraulic drive unit force control compensation method variable load stiffness and damping simulation

Morphogenesis of the Euplotid Ciliate Uronychia binucleata Young, 1922(Ciliophora, Hypotrichia)

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Journal of Ocean University of China 2019年第2期18卷 467-473页

作者： MA Honggang LI Jingbao WARREN Alan ba Sang LU Xiaoteng The Key Laboratory of Mariculture Ministry of Education Ocean University of China Key Laboratory for Space Bioscience and Biotechnology Institute of Special Environmental Biophysics School of Life Sciences Northwestern Polytechnical University Department of Life Sciences Natural History MuseumLondon School of Sciences Tibet University Research Department for Limnology University of Innsbruck

Morphogenesis of a population of the marine euplotid ciliate, Uronychia binucleata, which was found in Yellow Sea coastal waters next to a sewage outfall at a beach near Zhanqiao Pier, Qingdao, China, was investigated using protargol staining. The main pattern of morphogenesis is typical for the genus and can be summarized as follows: 1) the oral primordium in both proter and opisthe develops de novo in a subcortical pouch. In each daughter cell, the developing adoral zone of membranelles divides into two parts. The new membranelles formed in the proter's oral primordium will replace the leftmost five parental ones; six parental membranelles are retained by the proter; 2) the undulating membranes anlage is formed and develops independently from the oral primordium within the same subcortical pouch; 3) five primary front oventral-transverse cirral anlagen appear de novo on the cell surface; 4) the marginal cirral anlagen are formed de novo; 5) the leftmost frontal cirrus develops de novo on the cell surface; 6) two caudal cirri are formed at the posterior end of the rightmost anlage while the second primordium from the right gives rise to the third caudal cirrus. In contrast to its congeners, the anlage of the leftmost frontal cirrus is formed to the right of the undulating membranes anlage and before the formation of the latter.

关键词： Euplotida hypotrichs ontogenesis Uronychia