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A new guideline for diagnosis and treatment of syncope in children and adolescents that stimulates further thought and discussion

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Science Bulletin 2018年第23期63卷 1527-1528页

作者： julian M.Stewart Physiology and Medicine Center for HypotensionThe New York Medical CollegeValhallaNY 10595USA

A new guideline for diagnosis and treatment of syncope in children and adolescents was published by Chinese Pediatric Cardiology Society (CPCS)[1].This guideline admirably outlines a differential diagnosis of syncope in the Chinese population,placing appropriate emphasis on vasovagal syncope (VVS,simple faint), the most common *** authors appropriately discuss other more ominous causes of syncope such as cardiogenic syncope and neurogenic orthostatic *** particular,cardiogemc syncope can have lethal consequences if not promptly treated.

关键词： Children Adolescent syncope CPCS

The Materials Revolution

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Journal of Bionic Engineering 2006年第4期3卷 217-234页

作者： julian F.V.Vincent Department of Mechanical Engineering The University of Bath Bath BA2 7AY UK

In the final essay of this series the gaps between biology and engineering are examined, and methods are suggested for crossing them. Creativity is seen as the essential, and TRIZ （the Russian Theory of Inventive Problem Solving） is recommended as the best set of methods both for stimulating creativity and for solving technical problems. When the catalogue of Inventive Principles of TRIZ is used to bring biology and technology to the same level of detail, the comparison shows that the similarity is only about 12%. The differences largely reside in the reliance of energy as a controlling parameter in conventional technology and the replacement of energy by information in biological systems. Although we might be moving slowly in this direction, a numerically based comparison such as this should provide more impetus.

关键词： The Materials Revolution

Monitoring spatiotemporal soil moisture changes in the subsurface of forest sites using electrical resistivity tomography (ERT)

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Journal of Forestry Research 2022年第5期33卷 1649-1662页

作者： julian Fäth Julius Kunz Christof Kneisel Institute of Geography and Geology University of WürzburgAm Hubland97074 WürzburgGermany

The effects of drought on tree mortality at forest stands are not completely understood. For assessing their water supply, knowledge of the small-scale distribution of soil moisture as well as its temporal changes is a key issue in an era of climate change. However, traditional methods like taking soil samples or installing data loggers solely collect parameters of a single point or of a small soil volume. Electrical resistivity tomography (ERT) is a suitable method for monitoring soil moisture changes and has rarely been used in forests. This method was applied at two forest sites in Bavaria, Germany to obtain high-resolution data of temporal soil moisture variations. Geoelectrical measurements (2D and 3D) were conducted at both sites over several years (2015-2018/2020) and compared with soil moisture data (matric potential or volumetric water content) for the monitoring plots. The greatest variations in resistivity values that highly correlate with soil moisture data were found in the main rooting zone. Using the ERT data, temporal trends could be tracked in several dimensions, such as the interannual increase in the depth of influence from drought events and their duration, as well as rising resistivity values going along with decreasing soil moisture. The results reveal that resistivity changes are a good proxy for seasonal and interannual soil moisture variations. Therefore, 2D- and 3D-ERT are recommended as comparatively non-laborious methods for small-spatial scale monitoring of soil moisture changes in the main rooting zone and the underlying subsurface of forested sites. Higher spatial and temporal resolution allows a better understanding of the water supply for trees, especially in times of drought.

关键词： Geoelectrical monitoring Forest ecology Hydrology Soil water content

THE EFFECTS OF ROUGHNESS CHANGE ON THE SURFACE LAYER OF THE ATMOSPHERE(Ⅰ)--THE VARIATIONS OF WIND SPEED AND SHEAR STRESS

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Applied Mathematics and Mechanics(English Edition) 1991年第9期12卷 881-890页

作者： Xu Da-peng julian Hunt Institute of Mechanics Chinese Academy of SciencesBeijing Department of Applied Mathematics and Theoretical Physics University of CambridgeCambridgeBritain

A general four-layer structure linear theory for predicting the effects of arbitrarily distributed roughness change on the variations of wind speed and shear stress in the surface layer of 3D and 2D atmospheres was **... 详细信息

关键词： atmospheric boundary layer surface roughness

Nickel nanoparticles supported on nitrogen-doped carbon nanotubes are a highly active,selective and stable CO_(2) methanation catalyst

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Journal of Energy Chemistry 2021年第3期30卷 323-331页

作者： julian Godde Mariia Merko Wei Xia Martin Muhler Laboratory of Industrial Chemistry Ruhr University BochumD-44780 BochumGermany

CO_(2) methanation using nickel-based catalysts has attracted large interest as a promising power-to-gas *** nanoparticles supported on nitrogen-doped CNTs with Ni loadings in the range from 10 wt% to 50 wt% were synthesized by impregnation,calcination and reduction and characterized by elemental analysis,X-ray powder diffraction,H_(2) temperature-programmed reduction,CO pulse chemisorption and transmission electron *** Ni/NCNT catalysts were highly active in CO_(2) methanation at atmospheric pressure,reaching over 50% CO_(2) conversion and over 95% CH_(4) selectivity at 340℃ and a GHSV of50,000 mL g^(-1) h^(-1) under kinetically controlled *** small Ni particle sizes below 10 nm despite the high Ni loading is ascribed to the efficient anchoring on the N-doped *** optimum loading of 30 wt%-40 wt% Ni was found to result in the highest Ni surface area,the highest degree of conversion and the highest selectivity to methane.A constant TOF of 0.3 s^(-1) was obtained indicating similar catalytic properties of the Ni nanoparticles in the range from 10 wt%to 50 wt% Ni ***-term experiments showed that the Ni/NCNT catalyst with 30 wt% Ni was highly stable for 100 h time on stream.

关键词： CO_(2)methanation Nickel nanoparticles Carbon nanotubes Nitrogen doping

The Perception of Flood Risks: A Case Study of Babessi in Rural Cameroon

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International Journal of Disaster Risk Science 2021年第4期12卷 458-478页

作者： Gertrud Buchenrieder julian Brandl Azibo Roland Balgah Research Center RISK Institute of Sociology and EconomicsUniversität der Bundeswehr München85577NeubibergGermany Leibniz Institute of Agricultural Development in Transition Economies(IAMO) 06120Halle(Saale)Germany TUM School of Life Sciences Weihenstephan Technical University Munich(TUM)85354MunichGermany College of Technology The University of Bamenda(UBa)BamendaNorth West RegionCameroon

Although risk perception of natural hazards has been identified as an important determinant for sound policy design,there is limited empirical research on it in developing *** article narrows the empirical literature *** draws from Babessi,a rural town in the Northwest Region of *** was hit by a severe flash flood in *** cross-disciplinary lens applied here deciphers the complexity arising from flood hazards,often embedded in contexts characterized by poverty,a state that is constrained in disaster relief,and market-based solutions being *** data were collected via snowball *** logistic regression analysis suggests that individuals with leadership functions,for example,heads of households,perceive flood risk higher,probably due to their role as household *** found that risk perception is linked to location,which in turn is associated with religious *** perceive floods riskier than Muslims because the former traditionally reside at the foot of hills and the latter uphill;rendering Muslims less exposed and eventually less affected by ***,public disaster relief appears to have built up trust and subsequently reduced risk perception,even if some victims remained skeptical of state disaster *** indicates strong potential benefits of public transfers for flood risk management in developing countries.

关键词： Flood disaster Multinomial logistic regression Risk perception Rural Cameroon

Buoyancy and turbulence-driven atmospheric circulation over urban areas

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Journal of Environmental Sciences 2017年第9期29卷 63-71页

作者： Yifan Fan julian Charles Roland Hunt Yuguo Li Department of Mechanical Engineering The University of Hong KongHong KongChina Department of Earth Sciences University College LondonLondonWC1E6BTUK Malaysian Commonwealth Studies Centre CambridgeCB23RFUK

In the buoyancy and turbulence-driven atmospheric circulations（BTDAC） that occur over urban areas where the approach means wind speeds are very low（less than turbulent fluctuations and typically 3 m/sec）, the surface temperatures are significantly higher than those in the external rural areas, and the atmosphere above the mixing layer is stably stratified. In this paper, the mechanisms of BTDAC formation are studied through laboratory experiments and modelling, with additional low-level inflow from external rural areas and a divergent outflow in the opposite direction in the upper part of the mixed layer. Strong turbulent plumes in the central region mix the flow between lower and higher levels up to the inversion height. There are shear-driven turbulent eddies and weaker buoyant plumes around the periphery of the urban area. As the approach flow is very weak,the recirculating streamlines within the dome restrict the ventilation, and the dispersion of pollution emitted from sources below the inversion height leading to a rise in the mean concentration. Low-level air entrained from rural areas can, however, improve ventilation and lower this concentration. This trend can also be improved if the recirculating structure of the BTDAC flow pattern over urban areas breaks down as a result of the surface temperature distribution not being symmetrical, or as the approach wind speed increases to a level comparable with the mean velocity of circulation, or（except near the equator） the urban area is large enough that the Coriolis acceleration is significant.

关键词： Urban heat island Buoyancy and turbulence-driven Eddy structures Atmospheric circulation Pollutant dispersion

A Lagrangian mean theory on coastal sea circulation with inter-tidal transports ***

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Acta Oceanologica Sinica 2008年第6期27卷 1-16页

作者： FENG Shizuo julian JIANG Wensheng Key Laboratory of Physical Oceanography of Ministry of Education Institute of Physical Oceanography Ocean University ofChina Qingdao 266100 China

A brief review is made on the theory of the Lagrangian residual circulation and inter-tidal transports in a convectively weakly nonlinear system. In the review the emphasis is put on the systematical development of the theory and its weakness of convectively weakly nonlinear approximation. The fundamentals of a Lagrangian tidally-averaged theory on circulation with inter-tidal transport processes have been proposed for a general nonlinear coastal/estuarine system. The Lagrangian residual velocity is strictly de- fined, and it has been verified to be able to embody the velocity field of circulation. A new concept of the concentration for inter- tidal transport processes is presented. The concentration describing the inter-tidal transport processes should be a ＂Lagrangian inter-tidal concentration＂ defined and named, but not the Eulcrian tidally-averaged concentration used traditionally. The circulation described here contains a set of infinite temporal-spatial fields of velocity/concentration, each of which corresponds to a specific value of tidal phases varying continuously over one tidal cycle. When the convectively weakly nonlinear condition（ with a smaller order of eddy diffusion and sources） is approximately satisfied, a set of infinite temporal-spatial fields of velocity/concentration can be reduced to a single one.. the mass transport velocity/the Eulerian tidally averaged concentration as exhibited traditionally.

关键词： nonlinear shallow waters tide-dominating system coastal water circulation Lagrangian residual velocity Lagrangian inter-tidal concentration

Evolving concepts and opportunities in soil conservation

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International Soil and Water Conservation Research 2015年第1期3卷 1-14页

作者： julian Dumanski Consultant Sustainable Land ManagementOttawaCanada

The terrestrial landscape has changed considerably compared to that of the early 20th century when soil conservation was first *** portions of the land are already intensively managed,and the remainder is increasingly receiving human *** work on soil conservation focused attention on technological innovations,particularly control and mitigation of soil ***,land degradation has continued and actually accelerated in many parts of the world,due mainly to demands for continued economic development,using technologies that are highly *** many cases,this has been facilitated by highly inadequate and unsympathetic institutional,legislative,and policy *** paper discusses some of the new driving forces,new international programs,and new potential partners in soil ***,international efforts to mitigate land degradation are shifting from studies of the biophysical processes to improving the global,national and local enabling policy environment,as well as mainstreaming of soil conservation into national and regional policies and ***,increased emphasis is placed on economic instruments and international markets,such as carbon trading,and incorporation of non-market values in ecosystem investment,such as payment for ecosystem services,certification schemes,*** paper discusses some of the opportunities for soil conservation that accrue from these new driving forces.

关键词： Land degradation Environmental goods and services Driving forces