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Bone Research 2015年第1期3卷 40-45页

作者： douglas j DiGirolamo Vandana Singhal Xiaoli Chang Se-jin Lee Emily L Germain-Lee Department of Orthopaedic Surgery Johns Hopkins University School of Medicine Bone & Osteogenesis Imperfecta Department Kennedy Krieger Institute Department of Molecular Biology and Genetics Johns Hopkins University School of Medicine Department of Pediatrics Johns Hopkins University School of Medicine

Osteogenesis imperfecta（OI） comprises a group of heritable connective tissue disorders generally defined by recurrent fractures, low bone mass, short stature and skeletal fragility. Beyond the skeletal complications of OI,many patients also report intolerance to physical activity, fatigue and muscle weakness. Indeed, recent studies have demonstrated that skeletal muscle is also negatively affected by OI, both directly and indirectly. Given the well-established interdependence of bone and skeletal muscle in both physiology and pathophysiology and the observations of skeletal muscle pathology in patients with OI, we investigated the therapeutic potential of simultaneous anabolic targeting of both bone and skeletal muscle using a soluble activin receptor 2B（ACVR2B） in a mouse model of type Ⅲ OI（oim）. Treatment of 12-week-old oim mice with ACVR2 B for 4 weeks resulted in significant increases in both bone and muscle that were similar to those observed in healthy,wild-type littermates. This proof of concept study provides encouraging evidence for a holistic approach to treating the deleterious consequences of OI in the musculoskeletal system.

关键词： bone Administration of soluble activin receptor 2B increases bone and muscle mass in a mouse model of osteogenesis imperfecta

Quantifying golf course nitrogen use efficiency

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Grassland Research 2022年第3期1卷 174-186页

作者： Michael A.H.Bekken douglas j.Soldat Department of Soil Science University of Wisconsin-MadisonMadisonWisconsinUSA

Background:Previous studies have surveyed golf courses to determine nitrogen(N)fertilizer application rates on golf courses,but no previous studies have attempted to quantify how efficiently golf courses use ***:This study tests the ability of the growth potential(GP)N Requirement model as a benchmarking tool to predict a target level of N use on 76 golf courses in 5 regions of the US(Midwest,Northeast,East Texas,Florida,Northwest)and 3 countries in Europe(Denmark,Norway,UK).Results:The ratio of the golf course-wide N application rate to the GP N requirement prediction(termed the nitrogen efficiency score or NES)was 0.27,indicating that golf courses used 73%less N than predicted by the *** such,the GP N Requirement model needs to be recalibrated to predict N use on golf *** was achieved by adjusting the Nmax coefficient in the model.N rates on golf courses were widely variable both within and across *** regions had a coefficient of variation in N rates of 0.46 or ***:The high variation in N rates,which is largely unexplained by climate,economic factors,grass type,and soil type,may be indicative of inefficient N use in golf course management.

关键词： biophysical modeling decision support tools fertilizer golf growth potential nitrogen nitrogen efficiency turfgrass

Mitigating osteonecrosis of the jaw(ONj) through preventive dental care and understanding of risk factors

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Bone Research 2020年第1期8卷 14-25页

作者： jason TWan douglas MSheeley Martha jSomerman janice SLee National Institute of Dental and Craniofacial Research National Institutes of HealthBethesdaMDUSA Laboratory for Oral Connective Tissue Biology National Institute of Arthritis and Musculoskeletal and Skin DiseasesNational Institutes of HealthBethesdaMDUSA

It is well established that alterations in phosphate metabolism have a profound effect on hard and soft tissues of the oral cavity. The present-day clinical form of osteonecrosis of the jaw(ONj) was preceded by phosphorus necrosis of the jaw, ca. 1860. The subsequent removal of yellow phosphorus from matches in the early 20 th century saw a parallel decline in "phossy jaw" until the early 2000 s, when similar reports of unusual jaw bone necrosis began to appear in the literature describing jaw necrosis in patients undergoing chemotherapy and concomitant steroid and bisphosphonate treatment. Today, the potential side effect of ONj associated with medications that block osteoclast activity(antiresorptive) is well known, though the mechanism remains unclear and the management and outcomes are often unsatisfactory. Much of the existing literature has focused on the continuing concerns of appropriate use of bisphosphonates and other antiresorptive medications, the incomplete or underdeveloped research on ONj, and the use of drugs with anabolic potential for treatment of osteoporosis. While recognizing that ONj is a rare occurrence and ONj-associated medications play an important role in fracture risk reduction in osteoporotic patients, evidence to date suggests that health care providers can lower the risk further by dental evaluations and care prior to initiating antiresorptive therapies and by monitoring dental health during and after treatment. This review describes the current clinical management guidelines for ONj, the critical role of dental-medical management in mitigating risks, and the current understanding of the effects of predominantly osteoclast-modulating drugs on bone homeostasis.

关键词： drugs metabolism alterations

Oxygen and carbon isotope composition from the UHP Shuanghe marbles, Dabie Mountains, China

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Science China Earth Sciences 1999年第1期42卷 88-96页

作者：王清晨 douglas Rumble Geophysical Laboratory Carnegie Institution of Washington 5241 Broad Road N. W. Washington DC 20015-1305 U. S. A.

Investigations on the oxygen and carbon isotope compositions from the ultrahigh-pressure (UHP)-metamorphosed Shuanghe marbles, that occur as a member of a UHP slab, show that the δ18 O values range from +11.1% to+20.5% SMOW, and δ13 C from+1.0% to+5.7% PDB, respectively. The variations in isotope compositions show a centimeter scale of homogeneity and a heterogeneity of regional scale larger than 1 meter.In contrast to the eclogite marbles from Norway, the Shuanghe marbles have inherited the carbon isotope compositions from their sedimentary precursor. The δ13C shows positive correlation to the content of dolomite. The depletion in18O, compared with the pmtolithic carbonate strata, might result from three possible geological processes: 1) exchanging oxygen isotope with meteoric water before the UHP metamorphism, 2) decarbonation during the UHP metamorphism, and 3) exchanging oxygen isotope with country gneiss at local scale during retrograde metamorphism.It seems that the advection of fluid in the orogenic belt was very limited during subduction and exhumation of UHP rocks.

关键词： oxygen and carbon isotope UHP metamorphism Shuanghe marble Dabie Mountains of China.

High surface area biocarbon monoliths for methane storage

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Green Energy & Environment 2023年第5期8卷 1308-1324页

作者： Elizabeth Michaelis Renfeng Nie douglas Austin Yanfeng Yue Department of Chemistry Delaware State UniversityDoverDE 19901United States College of Chemical Engineering Zhengzhou UniversityZhengzhouHenan450001China

New energy sources that reduce the volume of harmful gases such as SO_(x)and NO_(x)released into the atmosphere are in constant *** gas,primarily made up of methane,is being widely used as one reliable energy source for heating and electricity generation due to its high combustion ***,natural gas accounts for a large portion of electricity generation and chemical feedstock in manufacturing plastics and other commercially important organic *** the near future,natural gas will be widely used as a fuel for ***,a practical storage device for its storage and transportation is very beneficial to the deployment of natural gas as an energy source for new *** this tutorial review,biomaterials-based carbon monoliths(CMs),one kind of carbonaceous material,was reviewed as an adsorbent for natural gas(methane)adsorption and storage.

关键词： Activated carbon Carbon monolith Methane storage High surface area Activation agent

Fuel characteristics, loads and consumption in Scots pine forests of central Siberia

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journal of Forestry Research 2020年第6期31卷 2507-2524页

作者： Galina A.Ivanova Elena A.Kukavskaya Valery A.Ivanov Susan G.Conard douglas j.McRae V.N.sukachev institute of forest sb ras-separate subdivision of the federal research center“krasnoyarsk science center of the siberian branch of the russian academy of sciences” krasnoyarskrussia 660036 M.F.reshetnev siberian state university of science and technology krasnoyarskrussia 660049 Emeritus scientist rocky mountain research stationu.s.forest servicemissoulamt 59807usa George mason university fairfaxvausa Canadian forest service natural resources canada1219 queen street eastsault st5.marieon p6a 2e5canada

Forest fuel investigations in central and southern Siberian taiga of Scots pine forest stands dominated by lichen and feather moss ground vegetation cover revealed that total aboveground biomass varied from 13.1 to 21.0 kg/m *** biomass was higher in plots in the southern taiga,while ground fuel loads were higher in the central *** developed equations for fuel biomass(both aerial and ground)that could be applicable to similar pine forest sites of Central *** loading variability found among plots is related to the impact and recovery time since the last wildfi re and the mosaic distribution of living *** consumption due to surface fi res of low to high-intensities ranged from 0.95 to 3.08 kg/m 2,that is,18–74%from prefi re *** total amount of fuels available to burn in case of fi re was up to 4.5–6.5 kg/m *** content of fuels(litter,lichen,feather moss)was related to weather conditions characterized by the Russian Fire Danger Index(PV-1)and FWI code of the Canadian Forest Fire Weather Index *** data obtained provide a strong foundation for understanding and modeling fi re behavior,emissions,and fi re eff ects on ecosystem processes and carbon stocks and could be used to improve existing global and regional models that incorporate biomass and fuel characteristics.

关键词： Pinus sylvestris Tree biomass Surface and ground fuel loads Fuel moisture Fuel consumption

Exploding lakes in Vanuatu ＂Surtseyan-style＂ eruptions witnessed on Ambae Island

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Episodes 2006年第2期29卷 87-92页

作者： Károly Németh Shane j. Cronin douglas Charley Morris Harrison Esline Garae Volcanic Risk Solutions Institute of Natural Resources Massey University PO Box 11 222 Palmerston North New Zealand Department of Geology Mines and Water Resources Private Bag Port Vila Vanuatu

After a long silence, Lake Vui on Ambae Island burst into spectacular life on November 28, 2005, disrupting the lives of the 10,000 inhabitants on this sleepy tropical island in the SW Pacific. ＂Surtseyan-style＂ explosions burst through the Island＇s summit lake waters, forming a new tuff-cone, and threatening to form deadly lahars or volcanic floods. Such eruptions are rarely well observed, and these fleeting opportunities provide a chance to match volcanic processes with rock-sequences common in the geologic record...

关键词：瓦努阿图爆发湖泊岛屿

Nrf2 is required for normal postnatal bone acquisition in mice

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Bone Research 2014年第4期2卷 231-240页

作者： jung-Hyun Kim Vandana Singhal Shyam Biswal Rajesh K Thimmulappa douglas j Di Girolamo Department of Environmental Health Sciences Johns Hopkins Bloomberg School of Public HealthBaltimoreMDUSA Department of Orthopaedic Surgery Johns Hopkins University School of MedicineBaltimoreMDUSA

A large body of literature suggests that bone metabolism is susceptible to the ill effects of reactive species that accumulate in the body and cause cellular dysfunction. One of the body＇s front lines in defense against such damage is the transcription factor, Nrf2. This transcription factor regulates a plethora of antioxidant and cellular defense pathways to protect cells from such damage. Despite the breadth of knowledge of both the function of Nrf2 and the effects of reactive species in bone metabolism, the direct role of Nrf2 in skeletal biology has yet to be thoroughly examined. Thus, in the current study, we have examined the role of Nrf2 in postnatal bone metabolism in mice. Mice lacking Nrf2 （Nrf2-/-） exhibited a marked deficit in postnatal bone acquisition, which was most severe at 3 weeks of age when osteoblast numbers were 12-fold less than observed in control animals. While primary osteoblasts from Nrf2-/- mice functioned normally in vitro, the colony forming capacity of bone marrow stromal cells （BMSCs） from these mice was significantly reduced compared to controls. This defect could be rescued through treatment with the radical scavenger N-acetyl cysteine （NAC）, suggesting that increased reactive species stress might impair early osteoblastogenesis in BMSCs and lead to the failure of bone acquisition observed in Nrf2-/- animals. Taken together, these studies suggest Nrf2 represents a key pathway in regulating bone metabolism, which may provide future therapeutic targets to treat osteoporosis.

关键词： bone Nrf2 is required for normal postnatal bone acquisition in mice

Heading control strategy assessment for coaxial compound helicopters

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Chinese journal of Aeronautics 2019年第9期32卷 2037-2046页

作者： Ye YUAN douglas THOMSON Renliang CHEN Richard DUNLOP National Key Laboratory of Rotorcraft Aeromechanics Nanjing University of Aeronautics&AstronauticsNanjing 210016China University of Glasgow Glasgow G12 8QQUnited Kingdom

The coaxial compound helicopter has two possible strategies for heading control: collective differential and rudder deflection. A flight dynamics model is developed to assess the effect of different heading control strategies. This includes the trim characteristics, steady flight performance,controllability, and manoeuvrability. The trim study demonstrates that heading control strategies are less influential on trim results, and the steady flight performance is also not significantly affected by the heading control strategy adopted. The controllability analysis shows although heading bandwidth and phase delay results at various speeds with different heading control strategies are all satisfied, the control derivative of the collective differential decreases as speed increases, and its heading aggressive agility is degraded into Level 3 in high-speed flight. In addition, using collective differential would lead to severe heading-rolling coupling as forward speed increases. On the contrary, the control derivative and aggressive agility of the rudder deflection is improved with forward speed, and there is no evidence of heading-rolling coupling. Finally, the transient turn MissionTask-Element(MTE) is utilized to investigate the heading manoeuvre characteristics in different heading control strategies, which indicates that the collective differential would add the amplitude of control input and the power consumption during this MTE.

关键词： Coaxial compound helicopter Control strategy Handling qualities Helicopter flight dynamics Helicopter performance

In Vivo Phosphorylation Site Mapping and Functional Characterization of Arabidopsis Phototropin 1

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Molecular Plant 2008年第1期1卷 178-194页

作者： Stuart Sullivan Catriona E. Thomson douglas j. Lamont Matthew A. jones john M. Christie Plant Science Group Division of Biochemistry and Molecular Biology. Institute of Biomedical and Life Sciences University of Glasgow. University Avenue. Glasgow Scotland UK FingerPrints Proteomics Facility Post-Genomics and Molecular Interactions Centre. School of Life Sciences MSI/WTB/CIR Complex University of Dundee. Dundee Scotland UK

Phototropins （phot1 and phot2） are blue-light receptor kinases controlling a range of responses that optimize the photosynthetic efficiency of plants. Light sensing is mediated by two flavin-binding motifs, known as LOVl and LOV2, located within the N-terminal region of the protein. Photoexcitation via LOV2 leads to activation of the C-terminal kinase domain and consequently receptor autophosphorylation. However, knowledge of the in-vivo phosphorylation sites for Arabidopsis phototropins is lacking and has impeded progress in elucidating the functional significance of receptor phos- phorylation. We have purified photl from Arabidopsis and identified the in-vivo sites of receptor phosphorylation by liquid chromatography tandem mass spectrometry. Arabidopsis-derived photl binds flavin mononucleotide as chromophore and is phosphorylated at four major sites located upstream of LOV2 （Ser^58, Ser^85, Ser^350, and Ser^410）, three of which are induced by blue light. Nevertheless, structure-function analysis indicates that the biological activity of photl can be attributed to a modular unit comprising the LOV2-kinase region of the protein. Thus, peptide regions upstream of LOV2, including the sites of receptor phosphorylation identified here, do not appear to be important for receptor signaling. By contrast, these regions may be necessary for maximizing stomatal performance and possibly light-induced relocalization of photl.

关键词： MODULAR UNIT Phototropins chromophores Phosphorylation Site Function analysis Upstream photosynthetic efficiency Arabidopsis PHOSPHONATION Receptor Signaling Flavin Mononucleotide Receptor