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Surface Macrofabric of Boulder Dominated Desert Mountain Slopes, California, USA

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Journal of Mountain Science 2005年第3期2卷 181-192页

作者： donald A. FRIEND Department of Geography Minnesota State University 7 Armstrong Hall Mankato MN 56001-6026 USA

Rhyolite domes formed over a million year continuum in eastern California are used to study boulder dominated slopes. Slopes in this study are steep （-25°to-35°） and are made of coarse boulder sized blocks. These slopes include well varnished vertically oriented colluvial deposits that have been likened to relict periglacial stone stripes, or as indicated in this study, are the result of ongoing desert slope processes. The deposits are common throughout the arid southwestern US, but their morphometric character, fabric, and rates of formation have not been assessed systematically. Results indicate that boulder deposits examined here are remnant from the original surface formed during volcanic eruption and that these boulder slope deposits evolve slowly. Grain size, grain shape and grain angularity do not change significantly from genesis to -0.6 Ma; trends in the data change markedly after that time. Mean eigenvectors indicate a fabric oriented downhill, parallel to the slope, consistent with the visual impression that long thin to plate-like rocks orient themselves similarly; however, fabric is actually randomly dispersed, similar to that at slope genesis, as indicated by the eigenvalue analysis resultants of C and K. Interestingly, grainsremain or become more angular over the million-year time scale of the study as they decrease in size, indicating active in situ weathering processes on individual grains; this result is counter to the common assumption that as grains weather they become more rounded over time.

关键词： Boulder-fields desert-slopes macrofabric

The effect of total carbon on microscopic soil properties and implications for crop production

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Journal of Arid Land 2012年第3期4卷 251-259页

作者： Inma LEBRON Milton Earl MCGIFFEN Jr donald Louis SUAREZ Centre for Ecology and Hydrology Bangor Gwynedd LL57 2UW UK Department of Botany and Plant Science University of California Riverside CA 92521-0334 USA U.S. Salinity Laboratory Riverside CA 92521-0334 USA

Soil structure is a dynamic property affected by physical, chemical, and microbiological processes. Addition of organic matter to soils and the use of different management practices have been reported to impact soil structure and crop production. Moderation in soil temperature and increases in microbial activity and soil water retention are often suggested as reasons for the rise in crop yield when organic matter is added to the soil. Less is known about the direct effect of changes in soil structure on crop production. A field experiment was conducted to study the effect of summer cover crop and in-season management system on soil structure. The experiment was a nested design with summer cover crop as the main plot and management system as the subplot. Summer cover crop treatments included cowpea （Vigna unguiculata L. Walp.） incorporated into the soil in the fall （CI）, cowpea used as mulch in the fall （CM）, sudangrass （Sorghum vulgare） incorporated into the soil in the fall （S）, and dry fallow or bare ground （B）. Management systems were organic （ORG） and conventional （CNV） systems. Lettuce （Lactuca sativa L.） and cantaloupes （Cucumis melo L.） were cultivated in rotation in the plots for three consecutive years using the same cover crops and management systems for each plot. Disturbed and undisturbed soil cores were collected at the end of the third year and used for laboratory experiments to measure physical, chemical, and hy- draulic properties. Image analysis was used to quantify soil structure properties using a scanning electron micro- scope on thin sections prepared from the undisturbed soil cores. We found that total soil carbon was correlated with porosity, saturation percentage, and pore roughness. Pore roughness was correlated with crop production in gen- eral and with marketable production in particular. We found that the higher the complexity of the pore space, the more water retained in the soil, which may increase soil water residence and reduce plant

关键词： summer cover crop management systems soil structure properties total carbon

Sports medician and science in soccer

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Journal of Sport and Health Science 2014年第4期3卷 249-250页

作者： donald T.Kirkendall Bing Yu Center for Learning Health Care Duke Clinical Research InstituteDurhamNC 27715USA Guest Editor Division of Physical Therapy University of North Carolina at Chapel HillChapel HillNC 27599USA Guest Editor

Can you name one sporting event that attracts more worldwide attention than the FIFA Worid Cup?Didn't think ***(football)iS the most widely played spo]。

关键词：体育赛事足球科学世界杯赞助商运动

A young women with a large ovarian mass

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Open Journal of Obstetrics and Gynecology 2013年第1期3卷 35-36页

作者： Vicky O’Dwyer Kevin hickey Midwestern Regional Hospital Limerick Ireland vicky.odwyer@ucd.ie

A dermoid ovarian cyst is the commonest ovarian cystin women of reproductive age. We report a young woman who presented with a large abdominal mass. We discuss the differential diagnosis and surgical management of a l... 详细信息

关键词： Ovarian Cyst Ovarian Cancer

An updated diced cartilage fascia technique for dorsal augmentation in rhinoplasty

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Plastic and Aesthetic Research 2019年第3期6卷 1-9页

作者： Jinli Wu donald B.Yoo Private practice Facial Plastic&Reconstructive SurgeryBeverly HillsCA 90212USA Division of Facial Plastic&Reconstructive Surgery Department of Otolaryngology-Head&Neck SurgeryUniversity of Southern CaliforniaLos AngelesCA 90033USA Division of Facial Plastic&Reconstructive Surgery Department of Otolaryngology-Head&Neck SurgeryUniversity of California-Los AngelesLos AngelesCA 90095USA

The aim of this paper is to discuss an updated technique for dorsal augmentation during rhinoplasty using diced cartilage wrapped in fascia. The usage of diced cartilage has been variously described in the literature with consistently satisfactory results. Herein, we present our experience with patients undergoing dorsal augmentation during rhinoplasty using an updated method of diced cartilage wrapped in fascia. Diced cartilage fascia techniques have become the technique of choice for dorsal augmentation for an ever-increasing number of rhinoplasty surgeons. The term is broadly descriptive and there remains a wide-range of ways to execute. Updating and enhancing the technique with greater attention to precision, and creating an aesthetically optimal and predictable result, may result in even improved outcomes for future patients.

关键词： Rhinoplasty revision rhinoplasty dorsal augmentation costal cartilage diced cartilage asian rhinoplasty DCF diced cartilage fascia

中国金融抑制对汇率和利率低估影响的研究——基于存量—流量连续模型的模拟

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中国金融抑制对汇率和利率低估影响的研究——基于存量—流量连续...

作者： Alfred hickey 南京大学

学位级别：硕士

中国的宏观经济阶段性地出现了两个明显的现象：低估的汇率和较低的利息率。本文使用储量--流量连续模型这一后凯恩斯学派的分析方法来模拟中国的宏观经济运行,并证明了使用该模型模拟中国经济的仃效性。同时本文文还将探讨汇率低估以... 详细信息

中国的宏观经济阶段性地出现了两个明显的现象：低估的汇率和较低的利息率。本文使用储量--流量连续模型这一后凯恩斯学派的分析方法来模拟中国的宏观经济运行,并证明了使用该模型模拟中国经济的仃效性。同时本文文还将探讨汇率低估以及低利率水平和金融抑制之间的关系在此先对这个学派和新古典经济学进行比较。自第二次世界大战以来,宏观经济学研究呈现出以凯恩斯主义为主导的现象,发展至今逐渐分为两个学派：新古典学派和后凯恩斯派。新古典经济学派的特征是使用货币数量论来解释相关模型,并且在模型中由于价格固定,所以一般都使用“一般均衡”。后凯恩斯模型的特点主要有：需求主导的经济增长、缺乏理性预期,信息的不确定性、加成定价、货币供给的内生性、不同的利息率、非均衡的结果、金融结构的影响。本文使用后凯恩斯性的模型。模型主要采用了需求主导的经济增长、加成定价、货币供给的内生性、不同的利息率、金融结构等方面。 2000年以后中国的宏观经济阶段性地出现了几个明显的曲线。媒体上最常看到的是中国外汇的汇率问题。外汇方面主要是中国国际收支不平衡的问题,就是说中国经常账户有顺差,资本账户租和金融账户有逆差。同时国内经济也有不平衡的方面。投资古GDP的比例比消费比例大。和其他的国家相比,中国的投资占GDP的比例特别高。另外一个方面是中国的储蓄率比投资率高。以下将对这些现象详细阐述：这些曲线部和两个现象有关系低估的汇的率和较低的利息率。个相关的概念是金融抑制。中国的金融体制包括金融抑制的政策：政府规定低估的利率、资本管制、高法定准备金。这些政策都控制了金融市场的自然运作。政府实施金融抑制政策为了它自己的利益。政府在两个地方获得好处：第一个是低估的利率使政府国债支付比较小。第二个是减少了坚持固定汇率的冲销成本。本文的模型模拟金融抑制的影响。本文使用的模型和方法来自Wynne GodJey和Marc Lavoie的Monetary Economics。这种模型的宏观经济模式由后凯恩斯学派创造。模式的形式受到主流经济学家James Tobin的影响。、为了分析贸易顺差的问题,本文必须用一个开放型经济模型,就是说至少要把两个国家放在模型里。为了分析投资增长和消费增长的关系,本文要用一个经济增长的模型。本文模型分别为两个国家,中国和美国。本文模型包括以下经济部门：家庭、企业、银行、央行、政府。这些部分有互相经济交易包括：消费、投资、国际贸易、政府支付、税、工资、利息支付、债款、存款、国债变量。本文模型为决定部分的经济关系使用行为函数。本文模型用固定工资和成本,这个意味着水平价格也是固定的。重要行为函数包括资本增长率、消费、利息率、国债需求。投资的增长率由债款利率和产能利用率所决定、投资的增长率也决定国内生产总值的增长率。消费由家庭的消费倾向还有它们的可支配收入决定。债款和国债利率被央行固定。为了保持银行的利润存款利率浮动。国债需求由银行和火行的需要决定。本文模型重要的特征是火行会发行自己的国债。国际贸易有各国进口倾向和汇率决定。本文假设模型中的汇率变动都是相对价格水平的变化。为了解中国经济的重要现象,本文用模型模拟低估汇率和低利率。用Excel表格模拟经济的演变,在模型中可以看出低估汇率和低利率对经济冲击的影响,模型送代得随着时间推移。模拟导致六个重要的论点： 1)模型正确的模拟低估汇率和低利率的影响,论文模型符合中国的国际收支状况,且准确反映了GDP变化。 2)低估汇率导致经常账户顺差和金融账户的逆差。因为模型中使用固定利率,且国债数额内生变动,因此政府必须发行国债。这个“货币冲销政策”不是为了控制通胀,而是为了稳定利率 3)因为金融抑制导致企业获得利益而家庭巡到损失。这个影响通过银行传导。 4)低利率有一个间接的影响：因为低利率刺激资本增长率上升,因而FDP增长率也相应提高。这意味着企业的利润也增加。 5)如果中国国债利率高于美国国债利率,低估人民币汇率会导致央行亏损。而低利率有助于防止这一结果发生 6)中国经常账户出现顺差的时候,储蓄高于投资。和没有顺差的情况相比,银行债务数额比较少而居民存款金额比较多。所以为了支持银行的利润,存款利率需要降低。

关键词：后凯恩斯宏观经济模型金融抑制金融压制汇率储量-流量连续

Grazing Impacts on the Diversity and Composition of Alpine Rangelands in Northwest Yunnan

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Journal of Plant Ecology 2013年第2期6卷 122-130页

作者： Michelle A.Haynes Zhendong Fang donald M.Waller Department of Botany University of Wisconsin-Madison430 Lincoln AvenueMadisonWI 53706USA and U.S.Fish&Wildlife ServiceNational Conservation Training Center698 Conservation WayShepherdstownWVUSA Shangri-La Alpine Botanical Garden P.O.Box 118Xianggelila CountyYunnanChina Department of Botany University of Wisconsin-Madison430 Lincoln AvenueMadisonWI 53706USA

Aims The eastern Himalayan region of southwest China represents the world’s most biodiverse temperate region as well as a cultural hot-spot undergoing rapid cultural and ecological *** area represents the center of origin for many plant groups including horticulturally valuable species of Pedicularis,Rhododendron and *** meadows here also provide summer pastures for Tibetan yak herders and the source for important medicinal *** levels for livestock here have quadrupled over the last five decades and shrubs are encroaching into many historical *** herders voice concerns over both shrub encroachment and shrinking *** this study,we sought to determine:(i)are alpine rangelands in Deqin County overgrazed and degraded?(ii)What are the local impacts of grazing on plant diversity and community composition?and(iii)which environmental variables covary with these differences in species composition across the grazing gradient?Methods To examine the ecological impacts of grazing in Deqin County,northwest Yunnan and assess its long-term sustainability,we used county records to determine historical population and livestock numbers,confirmed the results of interviews by Haynes(2011)and surveyed plant species richness and cover along a grazing gradient extending away from herder *** these transects,we sampled 1 m2 quadrats at 5 m intervals,noting species present and per-cent cover for vascular plants,grasses,sedges,rushes,moss,lichen,exposed rock,bare ground and *** also measured the average and maximum plant height within each *** then computed species richness for each of the 38 transects,calculating alpha and beta *** used one-way aNoVas to compare mean species richness values and average and maximum plant height across grazing *** chart changes in composition along the 100m gradient,we also plotted the percent cover of graminoid,forb,shrub and bare ground versus distance from the ***

关键词： alpine rangelands biodiversity conservationgrazing Southwest China

A metal-free composite photocatalyst of graphene quantum dots deposited on red phosphorus

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Journal of Environmental Sciences 2017年第10期29卷 91-97页

作者： donald K.L.Chan Jimmy C.Yu Yecheng Li Zhuofeng Hu Department of Chemistry The Chinese University of Hong Kong Shatin New Territories Shenzhen Research Institute The Chinese University of Hong Kong

A simple approach to enhance the photocatalytic activity of red phosphorus（P） was developed.A mechanical ball milling method was applied to reduce the size of red P and to deposit graphene quantum dots onto red P. The product was characterized by scanning electron microscopy, transmission electron microscopy, contact angle measurements, zeta-potential measurements, X-ray diffraction and UV–vis absorption spectroscopy. The product exhibited high visible-light-driven photocatalytic performance in the photodegradation of rhodamine B.

关键词： Metal-free photocatalyst Graphene quantum dots Red phosphorus Mechanical ball milling

A Review of Various Sources of Chitin and Chitosan in Nature

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Journal of Renewable Materials 2022年第4期10卷 1097-1123页

作者： Benedict Terkula Iber Nor Azman Kasan donald Torsabo Jenifer Wese Omuwa Higher Institution Center of Excellence(HICoE) Institute of Tropical Aquaculture and FisheriesUniversiti Malaysia TerengganuKuala Nerus21030Malaysia Department of Fisheries and Aquaculture Joseph Sarwuan Tarka University MakurdiMakurdi2373Nigeria

Chitin was first discovered by its name from the Greek word“chiton”,which means“mail coat”.It is indeed a polysaccharide made up of naturally occurring acetyl-D-glucosamine *** was the first researcher who extracted chitin from the shells of mollusks(crabs and lobsters),prawns,and crayfish in *** in 1811,Henri Braconnot discovered chitin in the cell walls of mushrooms and called it“fungine”.Chitin and chitosan are abundant in the biosphere as essential components of many organisms’exoskeletons and as by-products of the global seafood *** biopolymer must be deacetylated before chitosan can be *** can also be extracted using microbes in a biological extraction *** development of products that take advantage of the bioactivities of the existing primary commercial source of chitin(crustacean)has lagged ***,the disadvantages of the present commercial source such as seasonality and competition for other uses among others has been one of the driving forces towards seeking alternative sources of chitin and chitosan in *** review highlights some of the efforts made by environmental scholars to locate possible commercial sources of chitin and chitosan in nature over time.

关键词： Chitin chitosan crustaceans insects fungi