bluuebunny/crossref_metadata_2025 huggingface dataset:
Distributed MIMO radar target altitude estimation for ground‐based systems
Authors: Shin Hyuksoo , Chung Wonzoo
Published: December 2018

This study presents novel target altitude estimation schemes optimised for ground‐based multiple‐input multiple‐output (MIMO) radars with widely separated antennae, where the antennae are located in a plane so that the altitudes of the antennae are close together. For the ground‐based systems, existing target localisation methods based on linear least squares such as least square (LS) and bistatic range measurement (BRM) suffer from performance degradation in target altitude estimation and eventually fail in altitude localisation for a perfect ground‐based system where the altitude of antennae are the same. The authors propose three target altitude estimation schemes based on linear least squares for the ground‐based systems resolving the drawback of existing algorithms for the ground‐based systems; extended BRM approach, which estimates the square of target altitude from the auxiliary parameters produced by BRM algorithm, ellipsoid fitting approach, which directly estimates the square of target altitude with other target position information, and extended ellipsoid fitting approach, which utilise the estimation results of ellipsoid fitting approach to improve the target altitude estimation performance. Performance improvement of the proposed algorithms is analysed in terms of mean squared error and simulation results verify the performance.
Target tracking based on improved cubature particle filter in UWSNs
Authors: Feng Hailin , Cai Zhiwei
Published: December 2018

In this study, an improved cubature particle filter based on the artificial bee colony (ABC) algorithm is proposed and applied to target tracking via underwater wireless sensor networks (UWSNs). In the proposed method, the square root cubature Kalman filter is used to generate the proposal distribution and the ABC algorithm is employed to optimise the particles before resampling, which makes the particles move toward the high likelihood region and maintain the diversity of the particles. Moreover, linear minimum variance criterion is utilised to fuse local estimates together in distributed fusion architectures of UWSNs. The simulation results show that the proposed method outperforms other classical algorithms in tracking accuracy.
Numerical simulation of fast atmospheric pressure discharge in gas diode with plane-grid cathode system
Authors: Kozhevnikov Vasily , Kozyrev Andrey , Semeniuk Natalia , Kokovin Aleksandr
Published: December 2018

In this paper we perform an accurate time-dependent finite-element numerical gas discharge simulation in two-dimensional semi-periodic computational geometry of the gas diode with a plane-grid cathode system. The diode configuration we investigate is similar to previously studied experimentally. Discharge simulation is performed in the framework of two-moment macroscopic (hydrodynamic) discharge plasma model accounting photoionization and autoelectronic emission from nonuniform electrodes surfaces. The results of numerical calculations can be used for further estimations of a runaway electron flows characteristics.
Comparative Study of Optimization Algorithms for The Optimal Reservoir Operation
Authors: Liu Xinyuan , Zhu Yonghui , Li Lingyun , Chen Lu
Published: December 2018

Apart from traditional optimization techniques, e.g. progressive optimality algorithm (POA), modern intelligence algorithms, like genetic algorithms, differential evolution have been widely used to solve optimization problems. This paper deals with comparative analysis of POA, GA and DE and their applications in a reservoir operation problem. The results show that both GA and DES are feasible to reservoir operation optimization, but they display different features. GA and DE have many parameters and are difficult in determination of these parameter values. For simple problems with mall number of decision variables, GA and DE are better than POA when adopting appropriate parameter values and constraint handling methods. But for complex problem with large number of variables, POA combined with simplex method are much superior to GA and DE in time-assuming and quality of optimal solutions. This study helps to select proper optimization algorithms and parameter values in reservoir operation.
Research on Watershed Water Cycle Simulation Method Based on System Dynamics
Authors: Wu Jiang , Chen Jin , Xu Jijun , Wang Yongqiang , Li Qingqing
Published: December 2018

The process of rainfall and runoff in the watershed is nonlinear which strongly depends on precipitation, evaporation, infiltration and hydrodynamic characteristics of soil. Due to the random and complex nature of the natural state of runoff, the temporal and spatial variability of rainfall and runoff in the watershed is extremely complicated. In view of the ability of system dynamics to describe multivariate, high order, multi-loop, strong nonlinear and complex feedback relationships, and to analyze the feedback between variables, the water cycle dynamics model is established by using system dynamics method. According to the dynamic characteristics of hydrological process, the dynamic process of rainfall to runoff is analyzed, and the relationships between the variables in the model are characterized by specific differential equations. The case study in the Zhexi watershed shows that this model can accurately simulate the process of water cycle in the watershed which also performs well on hydrological forecasting. It has certain practical significance for expanding new idea on hydrological forecasting modeling.
Short-term Runoff Forecasting based on Hydrological Factors at Nanchang Section of Ganjiang River, China
Authors: Liu Bojun , Lei Xiaohui , Cai Siyu , Peng Shaoming , Zhang Dawei
Published: December 2018

With the change of global climate and underlying surface characteristics, and increasing human activities, hydro-meteorological factors such as precipitation, evaporation, and runoff. Etc., are directly affected, therefore the assumption of stationarity may no longer exist. In a changing environment, the conventional runoff forecasting methods become invalid, which brings challenges to accurate hydrometeorological forecast. A hydrological model based on the changing environment was employed to forecast the runoff at Nanchang Section of Ganjiang River in this paper, and the rationality and validity of the built model were verified. The results shows that the built hydrological model has high accuracy in the short-term runoff forecasting, and better forecasting effect has been obtained after the parameters calibration and the real-time correction of the predicted runoffs, which can provide the strong support for the scientific water resources operation decision and also provide the boundary conditions of water level and water quality for the hydrodynamic and water-quality simulation at the Nanchang Section of the Ganjiang River.
Ecological Strategies on the Demonstration of the Western Route Water Transfer
Authors: Wang Tongtong , Chen Hao
Published: December 2018

To comply with the national strategic layout adjustment in recent years, and to promote ecological civilization construction in China western region, it is necessary to study the opportunities and challenges in the Western Route Water Transfer demonstration brought by in ecological and environmental changes in both water-source regions and water receiving regions. By referring to the operation management experience of the Eastern and Middle routes of the South-to-North Water Transfer Project, this paper analyzed the ecological and environmental changes of the Western Route Project’s water transfer rivers, and the relationship between water and sediment of the Yellow River in water-receiving regions, found out the integrating point between the Western Route Project and the new development ideas, and finally concluded that the ecology must be given to priority in the demonstration of the Western Route Project. The early stage work of the Western Route Project needed to follow the general principles as for any major water conservancy project, which includes to demonstrate the project necessity given fully employing the water-saving potential, and to give highest priority to ecological security. Several relationships need be coordinated between: water source regions and water-receiving regions in water-saving, water ecological restoration and water resources development, water pollution control and water resources management, government leading and society participation, etc. These instruments above will guarantee both the water-source and water-receiving regions could benefit from the Western Route Project, help to solve the contradiction between ecological protection and water resources allocation, and facilitate achieving the target of sustainable development.
Application of an improved PSO algorithm mixed BFO algorithm in optimal scheduling of hydropower station
Authors: Zou Yibo , Li Mo , Xiao Xiaogang
Published: December 2018

The optimal scheduling of hydropower station is a constrained strong, nonlinear and multi-stage combinatorial optimization. Aiming at this issue, this paper analyses the shortcomings of previous PSO algorithm in hydropower station optimal scheduling model, and presents an improved PSO algorithm for hybrid BFO algorithm, which overcomes the problem that the PSO algorithm is easy to fall into local extremum and has strong dependence on parameters. A case study of a short-term scheduling period of a hydropower station is used to compare the improved PSO algorithm mixed BFO algorithm with previous PSO algorithm. The results show that the improved PSO algorithm can converge to the global optimal solution more accurately. Therefore, it provides a new method for solving the optimal scheduling model of hydropower station.
Study on Ecological Scheduling of the Xiaolangdi Reservoir Based on the Ecological Needs of Estuarine Fishes
Authors: Tian Shimin , Zhao Yi , Wang Yuanjian , Jiang Enhui , Yu Shoubing
Published: December 2018

The total water amount into the Yellow River estuary is significantly reduced with the construction of a series of reservoirs in the Yellow River, which has a lot of adversely effects on the fishes and fishery resources in the estuary. This research analyzes the impacts of the reservoirs on the runoff and discharge in the Lower Yellow River and the estuary, and pays more attention to the influences of the reduction of water amount on the estuarine ecology and fishes. As a large reservoir nearest to the estuary in the Lower Yellow River, the operation of Xiaolangdi Reservoir plays an important role on the ecological restoration of the lower reaches of the Yellow River and the estuary. Two ecological operation schemes are proposed based on the ecological demands of the estuarine fishes and the actual operation of the Xiaolangdi Reservoir in recent years. One scheme is proposed only on the basis of the estuarine ecological water demands and another scheme takes consideration of ecological water demands and the actual status of the water resources in the Lower Yellow River synthetically. Finally, the feasibility of the two schemes are analyzed according to the actual situation of water storage of the reservoirs in the Yellow River in 2017.
Study on the evolution law of density current in the Xiaolangdi Reservoir before the flood in 2018
Authors: Li Xinjie , Wang Yuanjian , Qu Shaojun , Wang Ting , Li Kunpeng
Published: December 2018

Sediment problems affect the operation life and comprehensive benefits of a reservoir. In response to the floods in the middle and upper reaches of the Yellow River, the Xiaolangdi Reservoir is subjected to preventative pre-discharge scheduling. Through a prototypical observation of the density current plunging zone of the Xiaolangdi Reservoir in 2018, we collected prototypical data of the water level, water-sediment characteristics, sediment thickness, thalweg points, and flow velocity, and analyzed the pre-dam distribution of density current and scouring-sedimentation characteristics during the flood dispatching period of the Xiaolangdi Reservoir. The research results promoted the understanding of the movement law of the density current of the Xiaolangdi Reservoir and the development of efficient sediment drainage technology for reservoirs.
An Information System Platform for Water Resources Operation in Shiyanghe River Basin, China
Authors: Cai Siyu , Lei Xiaohui , Liao Weihong , Yu Yang , Yu Lang
Published: December 2018

Currently, more and more arid and semi-arid areas in Northwestern China are facing with severe water problems. The Shiyanghe River basin is in the east of Hexi Corridor in Gansu Province with little rainfall and fragile ecological environment. As water pollution and water waste exist with water shortage, a serious conflict of water supply and demand is arising, accompanied with a series of water ecological problem. Thus, we must take measures to ensure the water resources to be used properly for long-term sustainable development. Water resources operation is taken reasonably which can achieve the overall regulation of basin water resources and which is an important method to achieve sustainable development. Taking the Shiyanghe River Basin as the research object, based on the basin data, this paper built the runoff forecasting model, water demand prediction model, water resources operation model and groundwater simulation model. Therefore, an information system platform for water resources operation in Shiyanghe River Basin is built based on GIS with an integrated data and computational models.
Ecological Operation Objectives for Four Major Chinese Carps Spawning in the Xijiang River
Authors: Wan Donghui , Xie Hehai , Yang Fang , Shi Yunyun , Ma Xinghua
Published: December 2018

The river basin cascade development has prominent influence on water ecology for breeding of four major Chinese carps, and the determination of ecological operation objectives is an important basic work to carry out the ecological operation. This study determines the main control indexes of reservoir operation by analysing the relationships between larval population of Xijiang Dongta spawning ground and impact indexes like water temperature, flood process and flow velocity. Taking peak flow, initial discharge, flow rising range, daily increasing rate of flow and duration of water level rising of the spawning ground as the control indexes, the target flow process of reservoir ecological operation can be determined. Furthermore, the drifting velocity of fish eggs is used as the test index to control the section flow in the scheduling river reach. The proposed method is applied to the ecological operation of Dongta spawning ground, and the target flow processes of ecological operation under low, medium and high flow levels are obtained.
Spatial and Temporal Distribution Characteristics of the humid index in North China Plain
Authors: Shuoyang LI , Guiyu YANG , Na DUAN , Lin WANG
Published: December 2018

With the development of economy and society and the increase of population, water shortage and a series of water-related problems became universal problems. The north China plain has become a global focal point due to the poor water resource background and the impact of climate change and high-intensity human activity. Water circulation, as the carrier of water resource evolution, was affected by climate change through evapotranspiration and also reacts on the climate through energy change. The humid index, as an index of regional water and heat budget, can reflect the circulation characteristics of water supply and consumption. And it can also connect the water cycle and energy cycle organically. The comprehensive index which can comprehensively reflect the degree of surface moisture -- the surface humid index was adopted to reveal the relationship between water budget and climate change in north China plain. Based on the daily meteorological data of 82 meteorological stations in north China plain from 1960 to 2017, the evolution of wetting degree in the whole region was analyzed and the main influencing factors of the change were analyzed in combination with the main meteorological elements. The relevant research is of certain reference value for sustainable development of north China plain and coping with future climate change.
Research on valuation of water system in source region of the yellow river based on emergy theory
Authors: Wang Yongqiang , Liu Zhiming , Yuan Zhe , Xu Jijun , Chen Jin
Published: December 2018

Taking the source region of the Yellow River as an example, this paper first introduces the theory of energy value and its basic steps. Then combined with the Yellow River source area, the variation characteristics of precipitation and surface water resources from 1961 to 2011 in the Yellow River source area were analyzed, and both of them showed a trend of decreasing year by year. On this basis, using the theory of energy value, combined with relevant parameters, taking 2011 year as an example, further analyses the chemical energy and solar energy of water resources in the Yellow River source area, and gives the value of surface water resources. The value of water resources per unit is 1.59 yuan/m3. For the Yellow River source area, the overall value of water resources for the whole basin in 2011 is 33.55 billion yuan. It can provide a reference for the analysis of the value of surface water resources in the Yellow River Basin.
Application of similarity analysis to flood forecasting
Authors: Zhangling Xiao , Zhongmin Liang , Binquan Li , Yan Zhou , Yanlan Wang
Published: December 2018

[Objective] There are plenty of useful information in hydrological observations. Predicting future flood on the basis of similarity information in historical records is an effective and promising approach. [Method] In this paper, a multi-measure similarity analysis method of rainstorms is developed based on “quantity”, “type” similarity indicators, the earth mover’s distance (EMD) and the rainstorm distribution similarity indicator. Search the similar rainstorm and its corresponding typical flood in historical library and then scale the typical flood process according to the ratio of rainfall amounts to achieve flood forecasting. [Result] The method is applied to a case study in Xinmiao station of Kuye River. The results show that with the accelerating information of rainstorm and flood process, the forecasted flood process is updated continuously, and the prediction accuracy is gradually increasing. [Conclusion] The proposed similarity analysis method is effective and applicable to flood forecasting.
The concentration, flux and occurrence process of total phosphorus in Dahuofang reservoir and Suggestions for environmental optimal operation
Authors: Li Xinghua , Dai Dan , Xu Xiangqin , Huang Guoxian , Sun Mingdong , Wang Tong , Yuan Honggang
Published: December 2018

Dahuofang reservoir is one of the most important drinking water sources in Liaoning province, China. Dynamics of total phosphorus (TP) concentration, flux and related retention processes in this reservoir are very important to the water quality management and drinking water safety. Based on the monitoring data of meteorology, hydrology, water quality and sediment from the main stations during 1992-2017, this paper analysed the TP fluxes in the different boundaries and the stocking process in both the overlying water and the active surface sediment layer using the mass balance method. This study revealed the TP accumulation variation in the overlying water and the surface sediment layer and the controlling mechanism of TP concentration in overlying water under different hydrological conditions. The results showed that the combination of flood and dry hydrological rhythms is important to maintain the dynamic balance of TP in the reservoir. Based on these results, to reduce the TP retention rate and accumulated TP in the active surface sediment layer, we put forward suggestions on environmental optimization operations during the early days of large flood and subsequent small flood season by opening the deep flood discharging holes of the reservoir and lowering upstream water level. These results provide an improved understanding and new eyesight of the nutrient control of large reservoirs in the north China.
Thoughts on Strengthening Safety of Rural Water Supply in the New Era-Taking Binxian County, Shaanxi Province as an Example
Authors: Liang Ji , Zhang Haitao , Qin Jinbo
Published: December 2018

At present, our country has entered a new era. The report of the 19th National Congress of CPC pointed out that we must always put the top priority of the Party’s work on solving the problem of agriculture, rural areas and farmers. The safety of rural water supply safety is the direct and realistic interest-related problem that the rural masses most concern. In the new era, we should further strengthen the safety work of rural water supply, gradually promote the integration of urban and rural water supply, and effectively solve the increasingly serious safety-related demand of water supply of villagers and the contradiction caused by uneven and insufficient development of urban and rural water supply. Binxian County is located in the water shortage area in the west of China. The management model of "urbanizing rural water supply" that the county explored to establish has effectively solved the problem about the construction, operation and maintenance of rural water supply project. It accords with the development idea of rural water supply in the new era, and its successful experience can be duplicated and popularized in Shaanxi Province and even in the whole country.
Study on the Motion Characteristics of Residual Air Mass in Pipelines in Water Transfer Project
Authors: Haocheng Huang , Jin Jiang , Qi Chen , Zhifang Liao , Laiquan Liu
Published: December 2018

For long-distance water transfer projects, the residual air mass in the pipeline will not only reduce the efficiency, but also be detrimental to the safety of the system. In order to study the influence of the water flow velocity of the pressurized water pipeline and the pipeline angle of the hump on the motion characteristics of the residual air mass, an experimental platform with Particle Image Velocimetry (PIV) measuring system was constructed to analyse the flow field. The RSM turbulence model was combined with the VOF multiphase flow model to construct a local high-point gas-liquid two-phase fluid dynamics model for numerical simulation. The results showed that with the increase of water flow velocity, the local hump residual air mass would go through three states, namely, no bubble generation, air bubble was generated and partial discharged, and air mass discharge at one time. If the gas was greater than a certain volume, the increase in the water flow rate required to carry the air mass out of the hump at one time would slow down; the larger the local hump angle was, the greater the water flow rate was required to carry the gas out of the local hump part.
Characteristics and Influence Factors of Water Consumption in China Pro-vincial Capital Cities by Means of Multivariate Regression Algorithm
Authors: Zhou Jinjun , Liu Jiahong , Wang Hao , Wang Zhongjing , Shao Weiwei
Published: December 2018

The city is a typical natural and social dual water circulation area. The water use characteristics of the city have obvious dual attributes, and there are many factors (both on nature and social side) affecting the urban water consumption (UWC). This article aimed to research the structure and characteristics of the UWC. Taking the provincial capital cities of China as the research objects, 24 index factors and data of the year 2015 were selected to construct a multivariate regression model between urban UWC and index factors. The results showed that the combination of correlation analysis and full subset regression could effectively screen the prediction variables of UWC. Principal component analysis could effectively reduce variable dimensions of UWC while preserving raw dataset information as much as possible. The main factors affecting UWC on the social side include the built-up area, the urban population, road cleaning area, residential electricity consumption, and per capital water consumption, and the main factors of the natural side include per capital green land and precipitation.
A Comprehensive Assessment of Drought and Climate Change
Authors: Qian yimin , Yao Shuiping , Yan Kun , Tang Wenjia
Published: December 2018

Drought is one of slow onset natural hazards with great impacts in many aspects, such as economy, agricultural and human health. To well manage drought, the areal coverage, duration and frequency can be analyzed and estimated to provide insight into historical perspective of drought events as well the long-term variation of climate in the study area. This study tries to explore the natural of drought including its definitions, categories, trigger mechanism and possible mitigation methods. This research studies the drought characteristics in Wyoming, United States based on the rainfall data from the U. S Historical Climatology Network (USHCN). The main approach is Standardized Precipitation Index (SPI), which provides the means to analyze drought at different time scales and discusses the relationship between drought and climate change.
Three-dimensional hydrodynamics numerical of wind-driven circulations in Danjiangkou Reservoir
Authors: Zhu Jie , Quan Jin , Lei Xiaohui , Yue Xia , Duan Yang
Published: December 2018

This paper focuses on the analysis of the flow field of Danjiangkou Reservoir under the action of wind stress. Based on the analysis of the annual wind field data of Danjiangkou Reservoir, the three-dimensional hydrodynamic model of Danjiangkou Reservoir was established. The distribution of water flow field in the reservoir area under five different wind directions and two different wind speeds was studied. The simulation results were compared with the flow field without wind. The results show that when the wind speed in the reservoir area is 3.3m/s, the surface velocity and flow direction change less under the same wind conditions as the potential flow direction. Under the wind condition opposite to the potential flow direction, the reservoir area is locally generated. The small circulation and surface flow are more disordered; when the wind speed reaches 10.0m/s, under the same wind condition as the potential flow direction, the surface velocity of the reservoir area increases significantly. Under the wind condition opposite to the direction of the potential flow, a stable counterclockwise circulation is generated, and the wind direction dominates the surface layer. seriously affecting the flow field distribution in the reservoir area. The research results in this paper can provide support for the reservoir in the formulation of emergency water pollution emergency strategy and the formulation of real-time scheduling plan.
A preliminary study on the navigation capacity improvement of the Yangtze River Waterway based on the joint dispatching optimization of the upstream reservoir group
Authors: Chen Yingjian , Fu Qiaoping , Ma Fangkai
Published: December 2018

The Yangtze River, which has the largest freight volume in the world, is a golden waterway of most importance in China. But there are still some sections with poor navigation standards that impede the potential of the channel from being fully exploited. This paper aims to investigate the possibility of navigation capacity improvement through the joint dispatching optimization of the controlled reservoir group in the upper Yangtze River. The construction and operation situations of the controlled reservoir group are introduced, and the contribution of the current joint dispatching scheme to the Yangtze River Waterway is then analysed. Based on the growing demand for inland water transportation, the possibility of navigation capacity improvement through the joint dispatching optimization is further investigated. The results show that the channel dimension of Yibin-Chongqing and Yichang-Chenglingji section has improved to a certain degree under the current joint dispatching mode, further promotion is possible through the optimization of joint dispatching for those years when the amount of suppliable water during dry seasons is much greater than the shipping demand. Policy suggestions on joint dispatching are finally proposed.
Research on the model of Human-Robot football professional skills competition
Authors: Ding Yong , Liu Jiefang
Published: December 2018

In this paper, the robot (humanoid robot) soccer activity is decomposed according to the process of Human-Robot football professional skill competition. This paper analyzes the shooting problem of robot in the forward range and outside the range of the door frame, applies it to the rotation angle of robot foot, and gives the mathematical model of linear motion through the force of the center of the ball. Then, the further research direction are discussed.
An Intrusion Detection Model based on Hybrid Classification algorithm
Authors: Ma Manfu , Deng Wei , Liu Hongtong , Yun Xinmiao
Published: December 2018

Due to using the single classification algorithm can not meet the performance requirements of intrusion detection, combined with the numerical value of KNN and the advantage of naive Bayes in the structure of data, an intrusion detection model KNN-NB based on KNN and Naive Bayes hybrid classification algorithm is proposed. The model first preprocesses the NSL-KDD intrusion detection data set. And then by exploiting the advantages of KNN algorithm in data values, the model calculates the distance between the samples according to the feature items and selects the K sample data with the smallest distance. Finally, by naive Bayes to get the final result. The experimental results on the NSL-KDD dataset show that the KNN-NB algorithm can meet the requirement of balanced performance than the traditional KNN and Naive Bayes algorithm in term of accuracy, sensitivity, false detection rate, specificity, and missed detection rate.
Design of Data Acquisition System Based on Zigbee for Wireless Sensor Networks
Authors: Lei Shi
Published: December 2018

With the continuous development of modern network technology, sensor technology and wireless communication technologies, the emergence and development of wireless sensor networks has been promoted. Among many wireless communication technologies, wireless communication technology featuring low power consumption, close proximity and low cost for ZigBee has attracted the research interest of researchers. Based on the current status of communication systems, based on the review and system analysis of wireless sensor networks, this paper proposes a ZigBee-based wireless sensor network data acquisition system, which avoids the reliability and installation of traditional wired sensor network data acquisition systems and shortcomings such as high maintenance costs and large wiring.
Optimizing Convolution Neural Network on the TI C6678 multicore DSP
Authors: Zeng Guozhao , Hu Xiao , Chen Yueyue
Published: December 2018

Convolutional Neural Networks (CNNs) have become the most advanced algorithms for deep learning. They are widely used in image processing, object detection and automatic translation. As the demand for CNNs continues to increase, the platforms on which they are deployed continue to expand. As an excellent low-power, high-performance, embedded solution, Digital Signal Processor (DSP) is used frequently in many key areas. This paper attempts to deploy the CNN to Texas Instruments (TI)’s TMS320C6678 multi-core DSP and optimize the main operations (convolution) to accommodate the DSP structure. The efficiency of the improved convolution operation has increased by tens of times.
A renewed framework for urban biodiversity governance: urban pigeons as a case-study
Authors: Skandrani Zina , Desquilbet Marion , Prévot Anne-Caroline
Published: December 2018

In a globally urbanizing world, interactions between individuals and nature are progressively decreasing. In this context, it is not uncommon that the presence of some remaining animal species in cities causes problems to urban citizens and results in conflicts among stakeholders. Here, we propose a novel vision of the relations between urban citizens, local authorities and urban nature, taking the example of urban pigeons. We combined ecological and sociological concepts as well as data to propose a new working framework to build an integrative governance of urban nature. We showed how effective it is to change the focus on elements of nature only by including the interrelations between humans and nature. We highlighted the importance of institutional messages when dealing with biodiversity issues. We conclude by calling for a holistic vision in the implementation of policy on urban nature.
Damit Informationen nicht versanden
Authors: Schmitz Daniela
Published: December 2018

Was passiert mit dem Erfahrungswissen von Mitarbeitern, die in den Ruhestand gehen? Oft leider nichts – es bleibt beim Ausscheidenden. Lesen Sie, wie der
Wissentranfser gelingt.
Am seidenen Faden …
Authors: Johansson Kajsa , Oswald Nadine-Marie
Published: December 2018

Wenn Führungskräfte merken, dass Mitarbeiter ausgelaugt sind, dann sollten sie handeln. Das ist gar nicht so einfach, wie es den Anschein hat. Lesen Sie,
welche Tipps die BGW bereit hält im vierten Teil der Serie „Gesundheit als Führungsaufgabe“.
Strahlenexposition beim Mammografie-Screening – eine Phantomstudie
Authors: Huber Evelyn , Zelzer Sarah
Published: December 2018

In Österreich wurde am 1. Januar 2014 das flächendeckende Mammografie-Screening als Brustkrebsfrüherkennungsprogramm eingeführt. Trotz der verbesserten Früherkennungsmöglichkeiten von Mammakarzinomen ist das Screening-Programm jedoch insbesondere aufgrund der Strahlenexposition immer wieder stark umstritten. In diesem Artikel werden Grundlagen zum Mammografie-Screening erörtert sowie die Ergebnisse einer Phantomstudie präsentiert.
Lumen-apposing stents versus plastic stents in the management of pancreatic pseudocysts: a large, comparative, international, multicenter study
Authors: Yang Juliana , Chen Yen-I , Friedland Shai , Holmes Ian , Paiji Christopher , Law Ryan , Hosmer Amy , Stevens Tyler , Matheus Franco , Pawa Rishi , Mathur Nihar , Sejpal Divyesh , Inamdar Sumant , Berzin Tyler M. , DiMaio Christopher J. , Gupta Sanchit , Yachimski Patrick S. , Anderloni Andrea , Repici Alessandro , James Theodore , Jamil Laith H. , Ona Mel , Lo Simon K. , Gaddam Srinivas , Dollhopf Markus , Alammar Nuha , Shieh Eugenie , Bukhari Majidah , Kumbhari Vivek , Singh Vikesh , Brewer Olaya , Sanaei Omid , Fayad Lea , Ngamruengphong Saowanee , Shin Eun Ji , Baron Todd H. , Khashab Mouen A.
Published: December 2018

Background Larger caliber lumen-apposing stents (LAMSs) have been increasingly used in the management of pancreatic fluid collections, specifically when solid debris is present; however, their advantages over smaller caliber plastic stents in the management of pancreatic pseudocysts are unclear. The aim of this study was to investigate the safety and efficacy of LAMS specifically in the management of pancreatic pseudocysts compared with double-pigtail plastic stents (DPPSs).

Methods We performed a multicenter, international, retrospective study between January 2012 and August 2016. A total of 205 patients with a diagnosis of pancreatic pseudocysts were included, 80 patients received LAMSs and 125 received DPPSs. Measured outcomes included clinical success, technical success, adverse events, stent dysfunction, pancreatic pseudocyst recurrence, and need for surgery.

Results Technical success was similar between the LAMS and the DPPS groups (97.5 % vs. 99.2 %; P = 0.32). Clinical success was higher for LAMSs than for DPPSs (96.3 % vs. 87.2 %; P = 0.03). While the need for surgery was similar between the two groups (1.3 % vs. 4.9 %, respectively; P = 0.17), the use of percutaneous drainage was significantly lower in the LAMS group (1.3 % vs. 8.8 %; P = 0.03). At 6-month follow-up, the recurrence rate was similar between the groups (6.7 % vs 18.8 %, respectively; P = 0.12). The rate of adverse events was significantly higher in the DPPS group (7.5 % vs. 17.6 %; P = 0.04). There was no difference in post-procedure mean length of hospital stay (6.3 days [standard deviation 27.9] vs. 3.7 days [5.7]; P = 0.31).

Conclusion When compared to DPPSs, LAMSs are a safe, feasible, and effective modality for the treatment of pancreatic pseudocysts and are associated with a higher rate of clinical success, shorter procedure time, less need for percutaneous interventions, and a lower overall rate of adverse events.
Welcher Belastungstest bei Verdacht auf stabile Angina
pectoris?
Authors: Dörr Rolf
Published: December 2018

Stress-Echo, Myokard-Perfusions-SPECT, Stress-Perfusions-MRT,
Dobutamin-Stress-MRT und CT-Angiografie sind dem Belastungs-EKG jeweils deutlich
überlegen. Das Belastungs-EKG kann eine stenosierende KHK bei höherer
KHK-Vortestwahrscheinlichkeit niemals mit Sicherheit ausschließen. Es wird
deshalb von der Nationalen VersorgungsLeitlinie Chronische KHK nur noch
eventuell als Methode zweiter Wahl für eine Vortestwahrscheinlichkeit zwischen
15 % und 30 % empfohlen.
Refractory Severe Thrombocytopenia during Pregnancy: How to Manage
Authors: Amorim Joana Gomes de , Abecasis Manuel Rocha , Rodrigues Filipa Maria Nogueira Lança
Published: December 2018

Thrombocytopenia is the most common hemostatic change in pregnancy, but severe thrombocytopenia is rare. One of the causes, immune thrombocytopenic purpura (ITP), is characterized by increased platelet destruction by immunoglobulin G (IgG) antibodies, presenting a high risk of hemorrhage for the patient, but also for the fetus, since antibodies may cross the placenta. We present the case of a 23-year-old pregnant woman with a history of Langerhans cell histiocytosis of the mandible submitted to surgery and chemotherapy when she was 10 years old, with diagnosis of ITP since then. At 28 weeks of gestation, she presented with petechiae, epistaxis, and gingival bleeding, with a platelet count of 3 × 109/L and positive IgG antiplatelet antibodies test. At a multidisciplinary discussion, it was decided to delay a cesarean section, due to the absence of fetal distress and to the high risk of morbidity for the patient. Many therapies were attempted without success. The IgG produced a slight and transient increase in the platelet count. On the 36th week of gestation, an elective cesarean section was performed. The perioperative period transfusions were guided by rotational thromboelastometry (ROTEM) monitoring. The procedure was performed under general anesthesia and videolaryngoscopy-assisted intubation. The patient was hemodynamically stable, without significant bleeding, and was transferred to the intensive care unit. The platelet count eventually decreased and a splenectomy was performed. Regional anesthesia may be contraindicated, and general anesthesia is associated with an increased risk of airway hemorrhage due to traumatic injury during the tracheal intubation and of hemorrhage associated with the surgical procedure. A multidisciplinary approach is essential in high-risk cases.
Early Intracranial Aneurysm Recurrence after Microsurgical Clip Ligation: Case Report and Review of the Literature
Authors: Marbacher Serge , Spiessberger Alexander , Diepers Michael , Remonda Luca , Fandino Javier
Published: December 2018

Microsurgical clip ligation is considered a definitive treatment for intracranial aneurysms (IAs), resulting in low rates of local recurrence that range from 0.2 to 0.5% and a latency period that averages about a decade. Our case report describes an early asymptomatic recurrence (i.e., without sentinel headache or seizure) less than 1 year after this 20-year-old woman underwent clip ligation of a ruptured anterior communicating artery (AComA) aneurysm. At recurrence, the patient underwent coiling of the regrowth; follow-up imaging at 6 and 18 months demonstrated complete IA occlusion. To review the putative risk factors of this rare phenomenon, the authors searched the PubMed database using the keywords “intracranial aneurysm,” “recurrence,” and “clipping” in various combinations. In the seven cases identified, all occurred in initially ruptured IA, which was often at the AComA, and six of seven patients were younger than 50 years old. Although most IA remnants grow slowly, early recurrence may represent a more aggressive biological behavior that warrants special attention in younger patients, positive rupture status, and unintended remnant of any size. In such a constellation, early imaging follow-up within the first 6 months may be warranted to rule out early IA recurrence
Psychiatrie: Vom Preis- zum Budgetsystem
Authors: Siebecker Julia , Dominikowski Isabella
Published: December 2018

Eigentlich sollte mit PEPP die Finanzierung der psychiatrischen Kliniken reformiert werden – zweimal wurden die Pläne geändert. Nun liegt ein neuer
Gesetzentwurf vor.
Half of Nobel Prize in Physics honors the inventors of chirped pulse amplification
Authors: Wilson R. Mark
Published: December 2018

The laureates circumvented an intrinsic limitation in laser technology to develop an amplification protocol now found in nearly every high-power, ultrafast system.
Chemistry Nobel winners harnessed evolution to teach old proteins new tricks
Authors: Miller Johanna L.
Published: December 2018

The combination of diversification and selection has proved a powerful recipe for creating enzymes and drugs.
US nuclear industry fights for survival
Authors: Kramer David
Published: December 2018

A glut of cheap natural gas, coupled with rapid increases in wind energy, is accelerating a decline in the US commercial nuclear industry when carbon-free energy has never been more important.
Belgium presses on with accelerator-driven research reactor
Authors: Feder Toni
Published: December 2018

Safer nuclear reactors or misguided promises? A new facility will put to test the old idea of using external neutrons to power fission.
Measuring cosmic distances with standard sirens
Authors: Holz Daniel E. , Hughes Scott A. , Schutz Bernard F.
Published: December 2018

The gravitational waves accompanying the merger of two massive compact objects encode the distance to the merger without the usual appeal to a hierarchy of length scales.
A new type of tropical Pacific warming—El Niño Modoki
Authors: Seow Marvin Xiang Ce
Published: December 2018

A familiar climate anomaly turns out to have a recently recognized relative.
Fiber-associated spirochetes are major agents of hemicellulose degradation in the hindgut of wood-feeding higher termites
Authors: Tokuda Gaku , Mikaelyan Aram , Fukui Chiho , Matsuura Yu , Watanabe Hirofumi , Fujishima Masahiro , Brune Andreas
Published: December 2018

Symbiotic digestion of lignocellulose in wood-feeding higher termites (family Termitidae) is a two-step process that involves endogenous host cellulases secreted in the midgut and a dense bacterial community in the hindgut compartment. The genomes of the bacterial gut microbiota encode diverse cellulolytic and hemicellulolytic enzymes, but the contributions of host and bacterial symbionts to lignocellulose degradation remain ambiguous. Our previous studies ofNasutitermesspp. documented that the wood fibers in the hindgut paunch are consistently colonized not only by uncultured members of Fibrobacteres, which have been implicated in cellulose degradation, but also by unique lineages of Spirochaetes. Here, we demonstrate that the degradation of xylan, the major component of hemicellulose, is restricted to the hindgut compartment, where it is preferentially hydrolyzed over cellulose. Metatranscriptomic analysis documented that the majority of glycoside hydrolase (GH) transcripts expressed by the fiber-associated bacterial community belong to family GH11, which consists exclusively of xylanases. The substrate specificity was further confirmed by heterologous expression of the gene encoding the predominant homolog. Although the most abundant transcripts of GH11 inNasutitermes takasagoensiswere phylogenetically placed among their homologs of Firmicutes, immunofluorescence microscopy, compositional binning of metagenomics contigs, and the genomic context of the homologs indicated that they are encoded by Spirochaetes and were most likely obtained by horizontal gene transfer among the intestinal microbiota. The major role of spirochetes in xylan degradation is unprecedented and assigns the fiber-associatedTreponemaclades in the hindgut of wood-feeding higher termites a prominent part in the breakdown of hemicelluloses.
Spontaneous migration of cellular aggregates from giant keratocytes to running spheroids
Authors: Beaune Grégory , Blanch-Mercader Carles , Douezan Stéphane , Dumond Julien , Gonzalez-Rodriguez David , Cuvelier Damien , Ondarçuhu Thierry , Sens Pierre , Dufour Sylvie , Murrell Michael P. , Brochard-Wyart Françoise
Published: December 2018

Significance

The migration of cellular populations drives influential and disparate biological processes, from the establishment of embryos to the invasion of cancerous tissues. Its deregulation can lead to improper development or pathogenesis of diseases. While many of the mechanisms that promote single-cell migration have been identified, how cell assemblies coordinate these mechanisms is poorly understood. This manuscript details modes of collective migration and the role of tissue dewetting in generating a symmetry breaking, which drives the spontaneous migration of cell aggregates
en masse
. This discovery, its corresponding assay, and the establishment of the underlying fundamental physical principles provide a powerful platform for further in-depth studies and insights into biological migration at the mesoscopic scale.
Simple yet functional phosphate-loop proteins
Authors: Romero Romero Maria Luisa , Yang Fan , Lin Yu-Ru , Toth-Petroczy Agnes , Berezovsky Igor N. , Goncearenco Alexander , Yang Wen , Wellner Alon , Kumar-Deshmukh Fanindra , Sharon Michal , Baker David , Varani Gabriele , Tawfik Dan S.
Published: December 2018

Abundant and essential motifs, such as phosphate-binding loops (P-loops), are presumed to be the seeds of modern enzymes. The Walker-A P-loop is absolutely essential in modern NTPase enzymes, in mediating binding, and transfer of the terminal phosphate groups of NTPs. However, NTPase function depends on many additional active-site residues placed throughout the protein’s scaffold. Can motifs such as P-loops confer function in a simpler context? We applied a phylogenetic analysis that yielded a sequence logo of the putative ancestral Walker-A P-loop element: a β-strand connected to an α-helix via the P-loop. Computational design incorporated this element into de novo designed β-α repeat proteins with relatively few sequence modifications. We obtained soluble, stable proteins that unlike modern P-loop NTPases bound ATP in a magnesium-independent manner. Foremost, these simple P-loop proteins avidly bound polynucleotides, RNA, and single-strand DNA, and mutations in the P-loop’s key residues abolished binding. Binding appears to be facilitated by the structural plasticity of these proteins, including quaternary structure polymorphism that promotes a combined action of multiple P-loops. Accordingly, oligomerization enabled a 55-aa protein carrying a single P-loop to confer avid polynucleotide binding. Overall, our results show that the P-loop Walker-A motif can be implemented in small and simple β-α repeat proteins, primarily as a polynucleotide binding motif.