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Numerical simulation of low-flow channel evolution due to sediment augmentation

2004年

作者： Joseph Kerman gary Tomlinson with Vivian Kerman.

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International Journal of Sediment Research 2012年第3期27卷 351-361页

作者： Hiroshi MIWA gary PARKER Department of Civil Engineering Maizuru National College of Technology Department of Civil and Environmental Engineering University of Illinois at Urbana-Champaign

For the conservation and restoration of river environment,a sediment replenishment technique, which conveys a part of the sediments excavated and/or dredged from reservoirs to the river below dams is developed and has been implemented tentatively in several *** placed as replenishment can be flushed out and transported downstream by floodwater or dam *** flushed sediments are expected to contribute to the control of degradation and the variation of the low-flow ***,this technique is in the development stage because there are many unknown ***,systematic investigations are necessary for practical management of the *** this study,the effects of the location of replenishment sediment on sediment flushing and on control of degradation were investigated by means of flume experiments.A two-dimensional numerical model was also developed to further investigate the effects of sediment augmentation on river *** numerical model treats bank erosion and sediment transport over fixed beds. The simulation results were verified against the experimental *** flushing process of replenishment sediment was investigated first,and then its effect as a countermeasure for river bed degradation was *** are summarized as follows:(1) Augmentation at upper riffles is effective for flushing of replenishment sediment and variation of low-flow channel.(2) Amelioration of degradation can be found in the cases of two types of *** amelioration effect of upper riffle placement was larger than that of lower riffle placement(3) Aggradation rate of the bed near the replenishment site in the fixed bed is large in the lower riffle placement compared with the upper riffle placement.(4) The numerical model was found to be generally successful as a predictive tool.

关键词： River restoration Low-flow channel Degradation Sediment replenishment Numerical simulation

Interfacial Strategies for Smart Slippery Surfaces

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Journal of Bionic Engineering 2020年第4期17卷 633-643页

作者： Glen McHale Rodrigo Ledesma-Aguilar gary George Wells Smart Materials&Surfaces Laboratory Faculty of Engineering and EnvironmentNorthumbria UniversityNewcastle upon TyneNE18STUK

The problem of contact line pinning on surfaces is pervasive and contributes to problems from ring stains to ice *** we provide a single conceptual framework for interfacial strategies encompassing five strategies for modifying the solid-liquid interface to remove pinning and increase droplet *** biomimetic strategies are included,(i)reducing the liquid-solid interfacial area inspired by the Lotus effect,(ii)converting the liquid-solid contact to a solid-solid contact by the formation of a liquid marble inspired by how galling aphids remove honeydew,and(iii)converting the liquid-solid interface to a liquid-lubricant contact by the use of a lubricant impregnated surface inspired by the Nepenthes Pitcher *** further strategies are,(iv)converting the liquid-solid contact to a liquid-vapor contact by using the Leidenfrost effect,and(v)converting the contact to a liquid-liquid-like contact using slippery omniphobic covalent attachment of a liquid-like coating(SOCAL).Using these approaches,we explain how surfaces can be designed to have smart functionality whilst retaining the mobility of contact lines and ***,we show how droplets can evaporate at constant contact angle,be positioned using a Cheerios effect,transported by boundary reconfiguration in an energy invariant manner,and drive the rotation of solid components in a Leidenfrost heat *** conceptual framework enables the rationale design of surfaces which are slippery to liquids and is relevant to a diverse range of applications.

关键词： superhydrophobicity SLIPS liquid marbles leidenfrost SOCAL

Spermatids do it differently! Paip2a--the essential regulator of spermiogenesis？

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Asian Journal of Andrology 2011年第1期13卷 122-124页

作者： Eileen A McLaughlin gary R Hime ARC Centre of Excellence in Biotechnology and Development Callaghan NSW 2308 Australia School of Environmental and Life Sciences University of Newcastle Callaghan NSW 2308 Australia Anatomy and Cell Biology University of Melbourne Parkville VIC 3010 Australia

The mechanisms underpinning the latter stages of spermiogenesis are poorly understood and male germ cells have been presumed to extensively employ post-tran- scriptional regulatory machinery,

关键词： Spermatids Paip2a-the essential

Low power 3.1–10.6 GHz IR-UWB transmitter for Gbps wireless communications

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Science China(Information Sciences) 2011年第5期54卷 1094-1102页

作者： WANG Albert ZHANG gary Department of Electrical Engineering University of California Riverside 92521 USA Skyworks Solutions Inc. Irvine CA USA

This paper reviews and discusses the design of a low-power single-full-band (3.1-10.6 GHz) non- carrier impulse-radio ultra wideband (UWB) transmitter featuring 5th-order Gaussian derivative pulse shaping, integrated BPSK modulation, and 2.5 kV whole-chip ESD (electrostatic discharge) protection. The UWB transmitter design has been implemented in a commercial 0.18 μm CMOS technology with a very small die size of 0.25 mm2. The fabricated chips have demonstrated full functionality, extremely low power consumption of 0.14 pJ/p-mV, and an ultra short pulse width of 394 ps. This ESD-protected UWB transmitter has the potential to support wireless streaming to gigabit per second (Gbps).

关键词： UWB impulse radio BPSK transmitter ESD protection

Stabilization of unstable pelvic fractures with a novel internal-external fixator

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Chinese Medical Journal 2011年第23期124卷 4112-4114页

作者： JIANG Zan-li gary Chen Department of Orthopedics Nanjing Zhongda Hospital Southeast University Nanjing Jiangsu 210009 China

An internal-external fixator for stabilization in three cases with unstable pelvic fractures were reported. Compared with external fixation, the internal-external fixator, which is placed in the subcutaneous layer, decreased the risk of pin-track infection, pin site pain, and bowel obstruction; meanwhile, it had the advantage of external fixation： it was easy to apply, controlled damage, and resulted in minimal injury.

关键词： stabilization, unstable pelvic fracture internal-external fixator

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Endogenous testosterone and mortality risk

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Asian Journal of Andrology 2018年第2期20卷 115-119页

作者： Emily J Meye gary Wittert Endocrine Diabetes and Metabolic Unit Royal Adelaide Hospital Port Road SA 5000 Australia Discipline of Medicine University of Adelaide Adelaide SA 5000 Australia Discipline of Medicine and Freemasons Foundation Centre for Men's Health University of Adelaide SA 5000 Australia

In men, obesity and metabolic complications are associated with lower serum testosterone （T） and dihydrotestosterone （DHT） and an increased risk of, and mortality from, multiple chronic diseases in addition to cardiovascular disease （CVD）. The causal interrelationships between these factors remain a matter of debate. In men with untreated congenital and lifelong forms of hypogonadotropic hypogonadism, there appears to be no increased risk. Men with Klinefelter＇s syndrome have an increased risk of various types of cancers, as well as CVD, which persist despite T therapy. In the absence of pathology of the hypothalamic-pituitary- gonadal axis, the effect of modest reductions in serum T in aging men is unclear. The prevalence of low serum T concentrations is high in men with cancer, renal disease, and respiratory disease and is likely to be an indicator of severity of systemic disease, not hypogonadism. Some population-based studies have found low serum T to be associated with a higher risk of deaths attributed to cancer, renal disease, and respiratory disease, while others have not. Although a meta-analysis of longitudinal studies has shown an association between low serum T and all-cause mortality, marked heterogeneity between studies limited a firm conclusion. Therefore, while a decrease in T particularly occurring later in life may be associated with an increase in all-cause and specific types of mortality in men, the differential effects, if any, of T and other sex steroids as compared to health and lifestyle factors are unknown at the current time.

关键词： hypogonadism mortality testosterone

Geodiversity in the Yellow River source zone

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Journal of Geographical Sciences 2013年第5期23卷 775-792页

作者： Brendon BLUE gary BRIERLEY YU Guo-an School of Environment University of Auckland Private Bag 92019 Auckland New Zealand Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China

It is a key premise of ＇ecosystem approaches＇ to natural resources management that we must have an appropriate understanding of biodiversity values, and controls upon them, if we wish to manage them effectively. These biodiversity values, and associated ecosystem functionality, vary with space and time and are tied directly to landscape-scale relationships and evolutionary traits. In riverine systems, nested hierarchical principles provide a useful platform to assess relationships between landscape components across a range of scales. These understandings are most instructively synthesized through catchment-scale analyses. This paper outlines a rationale for systematic catchment-wide appraisals of river geodiversity. An initial application of these principles is presented for the Yellow River source zone in Qinghai Province, western China. Geo-ecological relationships are outlined for five broad sections of the trunk stream, highlighting implications for the management of these individual landscape compartments and for the system as a whole.

关键词： geodiversity river classification anabranching Qinghai-Tibet Plateau Sanjiangynan Yellow River source zone

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Topographic Influence on Wetland Distribution and Change in Maduo County, Qinghai-Tibet Plateau, China

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Journal of Mountain Science 2012年第3期9卷 362-371页

作者： Jay GAO LI Xilai gary BRIERLEY School of Environment University of Auckland lo Symonds Street Auckland New Zealand College of Agriculture andAnimal Husbandry Qinghai University Xining 810016 China

Accurate information on the spatial distribution and temporal change of wetlands is vital to devise effective measures for their protection. This study uses satellite images in 1994 and 2001 to assess the effects of topography and proximity to channels on wetland change in Maduo County on the Qinghai-Tibet Plateau, western China. In 1994 wetlands in the study area extended over 6,780.0 km2. They were distributed widely throughout the county, with a higher concentration in the south, and were especially prominent close to streams. The pattern of wetlands demonstrated a bell-shaped distribution curve with elevation, ranging over hill slopes with gradients from 0-19°, the commonest gradient being around 3°. Although the aspects of these hill slopes range over all directions, there is a lower concentration of wetlands facing east and southeast. The extent of wetlands in 2001 decreased to 6,181.1 km2. Marked spatial differentiation in the pattern of wetlands is evident, as their area increased by 1,193.3 km2 at lower elevations but decreased by 1,792.2 km2 at higher ground, resulting in a net decrease of 598.8 km2. In areas with a gradient 9° the area of wetlands remained approximately consistent from 1994-2001. Newly retained wetlands are situated in relatively flat lowland areas, with no evident preference in terms of aspect. Wetlands on north-, east- and northeast-facing hillslopes with a bearing of 1-86° were more prone to loss of area than other orientations. The altered pattern of wetland distribution from higher to lower elevation on north-facing slopes coincided with the doubling of annual temperature during the same period, suggesting that climate warming could be an important cause.

关键词：湿地分布青藏高原中国西部玛多县地形低海拔地区湿地面积年平均气温

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Prevention and therapy of squamous cell carcinoma of the rodent esophagus using freeze-dried black raspberries

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Acta Pharmacologica Sinica 2007年第9期28卷 1422-1428页

作者： gary D STONER Robeena M AZIZ Division of Hematology and Oncology and Comprehensive Cancer Center Division of Environmental Health Sciences College of Public HealthThe Ohio State UniversityColumbusOH 43210USAUS Food and Drug AdministrationCenter for Drug Evaluation and ResearchSilver SpringMD 20903USA

Aim:This study was conducted to determine if short-term treatment of N-nitrosomethylbenzylamine (NMBA)-induced tumors in the rat esophagus withdietary freeze-dried black raspberries (FBR) would result in tumor regression andenhanced survival of the ***:Four-week-old male Fisher-344 ratswere administered an AIN-76A control diet and injected subcutaneously with 0.5mg/kg NMBA once per week for 15 *** 19 weeks,when rats had an averageof 5-6 tumors (papillomas) per esophagus,they were given a control diet contain-ing either 5%,10%,or 20% *** 7 weeks of berry treatment,all survivingrats were killed and tumor incidence,number and volume were ***:Esophageal tumor incidences,numbers and volumes in NMBA-treated rats werenot influenced by any of the berry *** were progressive increasesin the survival of NMBA-treated rats fed 5%-20% FBR diets;however,theseincreases were not ***:FBR at 5%,10%,and 20% of the diethad no effect on the development of NMBA-induced tumors in the rat esophagusor on animal survival when administered for 7 weeks beginning at the papillomastage of tumor ***,FBR appear to have no therapeutic value inthe treatment of esophageal *** contrast,dietary FBR are highly effectivein preventing the development of NMBA-induced esophageal tumors in rats whenadministered before and during NMBA treatment or shortly after NMBA treat-ment when the esophagi contain preneoplastic (dysplastic) lesions of varyingdegrees of severity.

关键词： chemoprevention therapy esophagus squamous cell carcinoma rodent black raspberries