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Dysfunctional stem and progenitor cells impair fracture healing with age 预览
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作者 Diane R Wagner Sonali Karnik +10 位作者 Zachary J Gunderson Jeffery J Nielsen Alanna Fennimore Hunter J Promer Jonathan W Lowery M Terry Loghmani Philip S Low Todd O McKinley Melissa A Kacena Matthias Clauss Jiliang Li 《世界干细胞杂志:英文版(电子版)》 2019年第6期281-296,共16页
Successful fracture healing requires the simultaneous regeneration of both the bone and vasculature;mesenchymal stem cells (MSCs) are directed to replace the bone tissue, while endothelial progenitor cells (EPCs) form... Successful fracture healing requires the simultaneous regeneration of both the bone and vasculature;mesenchymal stem cells (MSCs) are directed to replace the bone tissue, while endothelial progenitor cells (EPCs) form the new vasculature that supplies blood to the fracture site. In the elderly, the healing process is slowed, partly due to decreased regenerative function of these stem and progenitor cells. MSCs from older individuals are impaired with regard to cell number, proliferative capacity, ability to migrate, and osteochondrogenic differentiation potential. The proliferation, migration and function of EPCs are also compromised with advanced age. Although the reasons for cellular dysfunction with age are complex and multidimensional, reduced expression of growth factors, accumulation of oxidative damage from reactive oxygen species, and altered signaling of the Sirtuin-1 pathway are contributing factors to aging at the cellular level of both MSCs and EPCs. Because of these geriatric-specific issues, effective treatment for fracture repair may require new therapeutic techniques to restore cellular function. Some suggested directions for potential treatments include cellular therapies, pharmacological agents, treatments targeting age-related molecular mechanisms, and physical therapeutics. Advanced age is the primary risk factor for a fracture, due to the low bone mass and inferior bone quality associated with aging;a better understanding of the dysfunctional behavior of the aging cell will provide a foundation for new treatments to decrease healing time and reduce the development of complications during the extended recovery from fracture healing in the elderly. 展开更多
关键词 Fracture HEALING Aging Bone Angiogenesis MESENCHYMAL STEM CELLS Endothelial PROGENITOR CELLS
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Observation of e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?and study of the P-wave DsDs mesons
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作者 麦迪娜 M.N.Achasov +143 位作者 S.Ahmed M.Albrecht M.Alekseev A.Amoroso 安芬芬 安琪 白羽 O.Bakina R.Baldini Ferroli 班勇 K.Begzsuren D.W.Bennett J.V.Bennett N.Berger M.Bertani D.Bettoni F.Bianchi I.Boyko R.A.Briere 蔡浩 蔡啸 A.Calcaterra 曹国富 S.A.Cetin J.Chai 常劲帆 W.L.Chang G.Chelkov 陈刚 陈和生 陈江川 陈玛丽 陈申见 陈元柏 成伟帅 G.Cibinetto F.Cossio 代洪亮 代建平 A.Dbeyssi D.Dedovich 邓子艳 A.Denig I.Denysenko M.Destefanis F.De Mori 丁勇 董超 董静 董燎原 董明义 豆正磊 杜书先 范荆州 方建 房双世 方易 R.Farinelli L.Fava F.Feldbauer G.Felici 封常青 M.Fritsch 傅成栋 付颖 高清 高鑫磊 高原宁 高勇贵 高榛 B.Garillon I.Garzia A.Gilman K.Goetzen 龚丽 龚文煊 W.Gradl M.Greco 谷立民 顾旻皓 顾珊 顾运厅 郭爱强 郭立波 郭如盼 郭玉萍 A.Guskov Z.Haddadi 韩爽 郝喜庆 F.A.Harris 何康林 F.H.Heinsius T.Held 衡月昆 侯治龙 胡海明 胡继峰 胡涛 胡誉 黄光顺 黄金书 黄性涛 黄晓忠 黄智玲 N.Huesken T.Hussain W.Ikegami Andersson W.Imoehl M.Irshad 纪全 姬清平 季晓斌 季筱璐 姜侯兵 江晓山 蒋兴雨 焦健斌 焦铮 金大鹏 金山 金毅 T.Johansson N.Kalantar-Nayestanaki 康晓珅 M.Kavatsyuk 柯百谦 I.K.Keshk T.Khan A.Khoukaz P.Kiese R.Kiuchi R.Kliemt L.Koch O.B.Kolcu B.Kopf M.Kuemmel M.Kuessner A.Kupsc M.Kurth W.Kühn J.S.Lange P.Larin L. 《中国物理C:英文版》 SCIE CAS CSCD 2019年第3期5-16,共12页
Studies of e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?and the PP-wave charmed-strange mesons are performed based on an e+e?e+e?collision data sample corresponding to an integrated luminosity of 567 pb?1 collected with ... Studies of e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?and the PP-wave charmed-strange mesons are performed based on an e+e?e+e?collision data sample corresponding to an integrated luminosity of 567 pb?1 collected with the BESIII detector at s√=4.600s=4.600 GeV.The processes of e+e?→D+sDˉˉˉˉ?0K?e+e?→Ds+Dˉ?0K?and D+sDˉˉˉˉ0K?Ds+Dˉ0K?are observed for the first time and are found to be dominated by the modes D+sDs1(2536)?Ds+Ds1(2536)?and D+sD?s2(2573)?Ds+Ds2?(2573)?,respectively.The Born cross sections are measured to beσB(e+e?→D+sDˉˉˉˉ?0K?)=(10.1±2.3±0.8)σB(e+e?→Ds+Dˉ?0K?)=(10.1±2.3±0.8)pb andσB(e+e?→D+sDˉˉˉˉ0K?)=(19.4±2.3±1.6)σB(e+e?→Ds+Dˉ0K?)=(19.4±2.3±1.6)pb,and the products of Born cross section and the decay branching fraction are measured to beσB(e+e?→D+sDs1(2536)?+c.c.)?σB(e+e?→Ds+Ds1(2536)?+c.c.)?B(Ds1(2536)?→Dˉˉˉˉ?0K?)=(7.5±1.8±0.7)B(Ds1(2536)?→Dˉ?0K?)=(7.5±1.8±0.7)pb andσB(e+e?→D+sD?s2(2573)?+c.c.)?B(D?s2(2573)?→Dˉˉˉˉ0K?)=σB(e+e?→Ds+Ds2?(2573)?+c.c.)?B(Ds2?(2573)?→Dˉ0K?)=(19.7±2.9±2.0)(19.7±2.9±2.0)pb.For the Ds1(2536)?Ds1(2536)?and D?s2(2573)?Ds2?(2573)?mesons,the masses and widths are measured to be M(Ds1(2536)?)=(2537.7±0.5±3.1)MeV/c2M(Ds1(2536)?)=(2537.7±0.5±3.1)MeV/c2,Γ(Ds1(2536)?)=(1.7±1.2±0.6)Γ(Ds1(2536)?)=(1.7±1.2±0.6)MeV,and M(D?s2(2573)?)=M(Ds2?(2573)?)=(2570.7±2.0±1.7)MeV/c2,(2570.7±2.0±1.7)MeV/c2,Γ(D?s2(2573)?)=(17.2±3.6±1.1)Γ(Ds2?(2573)?)=(17.2±3.6±1.1)MeV.The spin-parity of the D?s2(2573)?Ds2?(2573)?meson is determined to be JP=2+JP=2+.In addition,the processes e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?are searched for using the data samples taken at four(two)center-of-mass energies between 4.416(4.527)and 4.575 GeV,and upper limits at the 90%confidence level on the cross sections are determined. 展开更多
关键词 cross section P-WAVE D_s MESONS resonance parameters spin-parity BESIII
Evidence for the decays of ∧c^+→∑^+η and ∑^+η’
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作者 麦迪娜 M.N.Achasov +146 位作者 S.Ahmed M.Albrecht M.Aleksee A.Amoroso 安芬芬 安琪 白羽 O.Bakina R. Baldini Ferroli 班勇 K.Begzsuren D.W.Bennett J.V.Bennett N.Berger M.Bertani D.Bettoni F.Bianchi I.Boyko R.A.Briere 蔡浩 蔡啸 O.Cakir A.Calcaterra 曹国富 S.A.Cetin J.Chai 常劲帆 W.L.Chang G.Chelkov 陈刚 陈和生 陈江川 陈玛丽 陈平亮 陈申见 陈元柏 成伟帅 G.Cibinetto F.Cossio 代洪亮 代建平 A.Dbeyssi D.Dedovich 邓子艳 A.Denig I.Denysenko M.Destefanis F.De Mori 丁勇 董超 董静 董燎原 董明义 豆正磊 杜书先 段鹏飞 范荆州 方建 房双世 方易 R.Farinelli L.Fava S.Fegan F.Feldbauer G.Felici 封常青 M.Fritsch 傅成栋 付颖 高清 高鑫磊 高原宁 高勇贵 高榛 B.Garillon I.Garzia A.Gilman K.Goetzen 龚丽 龚文煊 W.Gradl M.Greco 谷立民 顾旻皓 顾运厅 郭爱强 郭立波 郭如盼 郭玉萍 A.Guskov Z.Haddadi 韩爽 郝喜庆 F.A.Harris 何康林 F.H.Heinsius T.Held 衡月昆 侯治龙 胡海明 胡继峰 胡涛 胡誉 黄光顺 黄金书 黄性涛 黄晓忠 黄智玲 T.Hussain N.Hu sken W.Ikegami Andersson M.Irshad 纪全 姬清平 季晓斌 季筱璐 江晓山 蒋兴雨 焦健斌 焦铮 金大鹏 金山 金毅 T.Johansson A.Julin N.Kalantar-Nayestanaki 康晓珅 M.Kavatsyuk 柯百谦 I.K.Keshk T.Khan A.Khoukaz P.Kiese R.Kiuchi R.Kliemt L.Koch O.B.Kolcu B.Kopf M.Kornicer M.Kuemmel M.Kuessner A.Kupsc M.Kurth W.Kuhn J.S.Lange P.Larin L.La 《中国物理C:英文版》 SCIE CAS CSCD 2019年第8期15-23,共9页
We study the hadronic decays of ∧c^+ to the final states ∑^+η and ∑^+η, using an e^+e^- annihilation data sample of 567 pb^-1 taken at a center-of-mass energy of 4.6 GeV with the BESIII detector at the BEPCII col... We study the hadronic decays of ∧c^+ to the final states ∑^+η and ∑^+η, using an e^+e^- annihilation data sample of 567 pb^-1 taken at a center-of-mass energy of 4.6 GeV with the BESIII detector at the BEPCII collider. We find evidence for the decays ∧^+→∑^+η and ∑^+η' and with statistical significance of and , respectively. Normalizing to the reference decays ∧^+→∑^+π^0 and ∑^+ω, we obtain the ratios of the branching fractions B(∧C^+→∑^+η)/V(∧^→∑^+π^0)and B(∧C^+→∑^+η)/B(∧C^+→∑^+ω)to be and , respectively. The upper limits at the 90% confidence level are set to be B(∧C^→∑^+η)/V(∧^+→∑^+π^0)<0.58 and B(∧C^+→∑^+η)/B(∧C^+→∑^+ω)<1.2. Using BESIII measurements of the branching fractions of the reference decays, we determine B(∧C^+→∑^+η)=(0.41±019±0.05)%(<0.68%) and B(∧C^+→∑^+η)=(1.34+0.53+0.19)%(<1.9%). Here, the first uncertainties are statistical and the second systematic. The obtained branching fraction of ∧C^+→∑^+η is consistent with the previous measurement, and the branching fraction of ∧C^+→∑^+η is measured for the first time. 展开更多
关键词 charmed BARYON ∧c^+ DECAYS branching FRACTIONS
Nonadiabatic dynamics and geometric phase of an ultrafast rotating electron spin
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作者 Xing-Yan Chen Tongcang Li Zhang-Qi Yin 《科学通报:英文版》 SCIE EI CSCD 2019年第6期380-384,共5页
The spin in a rotating frame has attracted a lot of attentions recently,as it deeply relates to both fundamental physics such as pseudo-magnetic field and geometric phase,and applications such as gyroscopic sensors.Ho... The spin in a rotating frame has attracted a lot of attentions recently,as it deeply relates to both fundamental physics such as pseudo-magnetic field and geometric phase,and applications such as gyroscopic sensors.However,previous studies only focused on adiabatic limit,where the rotating frequency is much smaller than the spin frequency.Here we propose to use a levitated nano-diamond with a built-in nitrogen-vacancy(NV)center to study the dynamics and the geometric phase of a rotating electron spin without adiabatic approximation.We find that the transition between the spin levels appears when the rotating frequency is comparable to the spin frequency at zero magnetic field.Then we use Floquet theory to numerically solve the spin energy spectrum,study the spin dynamics and calculate the geometric phase under a finite magnetic field,where the rotating frequency to induce resonant transition could be greatly reduced. 展开更多
关键词 Nitrogen-vacancy center NONADIABATIC GEOMETRIC phase ULTRAFAST ROTOR RABI oscillation OPTOMECHANICS
Late Cretaceous non-avian dinosaurs from the James Ross Basin,Antarctica:description of new material,updated synthesis,biostratigraphy,and paleobiogeography 预览
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作者 Matthew CLAMANNA Judd ACASE +7 位作者 Eric MROBERTS Victoria MARBOUR Ricardo CELY Steven WSALISBURY Julia ACLARKE DEdward MALINZAK Abagael RWEST Patrick MO’CONNOR 《极地科学进展:英文版》 CSCD 2019年第3期228-250,共23页
Although the fossil record of non-avian dinosaurs from the Cretaceous of Antarctica is the poorest of any continent,fossils representing at least five major taxonomic groups(Ankylosauria,early-diverging Ornithopoda,Ha... Although the fossil record of non-avian dinosaurs from the Cretaceous of Antarctica is the poorest of any continent,fossils representing at least five major taxonomic groups(Ankylosauria,early-diverging Ornithopoda,Hadrosauridae,Titanosauria,and Theropoda)have been recovered.All come from Upper Cretaceous(Coniacian–Maastrichtian)marine and nearshore deposits belonging to the Gustav and Marambio groups of the James Ross Basin at the northern tip of the Antarctic Peninsula.The majority of these finds have come from the Campanian–Maastrichtian Snow Hill Island and López de Bertodano formations of James Ross and Vega islands.Given the rarity of Antarctic Cretaceous non-avian dinosaurs,discoveries of any fossils of these archosaurs,no matter how meager,are of significance.Here we describe fragmentary new ornithischian(ankylosaur and ornithopod)material from the upper Campanian–lower Maastrichtian Cape Lamb Member of the Snow Hill Island Formation and the Maastrichtian Sandwich Bluff Member of the López de Bertodano Formation.One of these specimens is considered to probably pertain to the holotypic individual of the early-diverging ornithopod Morrosaurus antarcticus.We also provide an up-to-date synthesis of the Late Cretaceous non-avian dinosaur record of the James Ross Basin and analyze the biostratigraphic occurrences of the various finds,demonstrating that most(including all named taxa and all reasonably complete skeletons discovered to date)occur within a relatively condensed temporal interval of the late Campanian to early Maastrichtian.Most or all James Ross Basin dinosaurs share close affinities with penecontemporaneous taxa from Patagonia,indicating that at least some continental vertebrates could disperse between southern South America and Antarctica during the final stages of the Mesozoic. 展开更多
关键词 Dinosauria ANTARCTICA Cretaceous James Ross Basin BIOSTRATIGRAPHY PALEOBIOGEOGRAPHY
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Characterization of a novel murine Sost ERT2 Cre model targeting osteocytes 预览
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作者 Delphine B.Maurel Tsutomu Matsumoto +8 位作者 Julian A.Vallejo Mark L.Johnson Sarah L.Dallas Yukiko Kitase Marco Brotto Michael J.Wacker Marie A.Harris Stephen E.Harris Lynda F.Bonewald 《骨研究:英文版》 SCIE CAS CSCD 2019年第1期41-53,共13页
Transgenic mice are widely used to delete or overexpress genes in a cell specific manner to advance knowledge of bone biology,function and disease.While numerous Cre models exist to target gene recombination in osteob... Transgenic mice are widely used to delete or overexpress genes in a cell specific manner to advance knowledge of bone biology,function and disease.While numerous Cre models exist to target gene recombination in osteoblasts and osteoclasts,few target osteocytes specifically,particularly mature osteocytes.Our goal was to create a spatial and temporal conditional Cre model using tamoxifen to induce Cre activity in mature osteocytes using a Bac construct containing the 5’and 3’regions of the Sost gene(Sost ERT2 Cre).Four founder lines were crossed with the Ai9 Cre reporter mice.One founder line showed high and specific activity in mature osteocytes.Bones and organs were imaged and fluorescent signal quantitated.While no activity was observed in 2 day old pups,by 2 months of age some osteocytes were positive as osteocyte Cre activity became spontaneous or‘leaky’with age.The percentage of positive osteocytes increased following tamoxifen injection,especially in males,with 43%to 95%positive cells compared to 19%to 32%in females.No signal was observed in any bone surface cell,bone marrow,nor in muscle with or without tamoxifen injection.No spontaneous signal was observed in any other organ.However,with tamoxifen injection,a few positive cells were observed in kidney,eye,lung,heart and brain.All other organs,28 in total,were negative with tamoxifen injection.However,with age,a muscle phenotype was apparent in the Sost-ERT2 Cre mice.Therefore,although this mouse model may be useful for targeting gene deletion or expression to mature osteocytes,the muscle phenotype may restrict the use of this model to specific applications and should be considered when interpreting data. 展开更多
关键词 cell KNOWLEDGE MODEL
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Agricultural Development and Implication for Wetlands Sustainability: A Case from Baoqing County, Northeast China 预览
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作者 FANG Chong WEN Zhidan +4 位作者 LI Lin DU Jia LIU Ge WANG Xiaodi SONG Kaishan 《中国地理科学:英文版》 SCIE CSCD 2019年第2期231-244,共14页
Historical thematic maps and remote sensing data were applied to address spatiotemporal dynamics of land use/land cover(LULC)changes and its impact on wetlands sustainability based on eight LULC datasets from 1954 to ... Historical thematic maps and remote sensing data were applied to address spatiotemporal dynamics of land use/land cover(LULC)changes and its impact on wetlands sustainability based on eight LULC datasets from 1954 to 2015 in Baoqing County,Northeast China.This study demonstrated that LULC drastically changed in the past six decades due to conversion of wetlands,woodland,and grassland into cropland.The cropland was 578.8 km~2 in 1954,accounting for 5.8% of the area in Baoqing County,and it increased to 54.3% in 2015,which was nearly equivalent to 9.4 times of that in 1954.Cropland increased 4843.6 km~2 from 1954 to 2015 with average increased area of 79.4 km~2/yr.The conversion of wetlands was the main reason for cropland increase(49.7%),and woodland(18%)and grassland(16.3%)conversion were other reasons.Results also revealed that 78% of wetlands were lost during the past six decades,of which 91.2% were converted cropland.Population increasing(population across Baoqing in 2015 was 7.8 times of that in 1949),agricultural technology development was the main reason for cropland increase,institutional and economic policies also played important roles for cropland dynamics,particularly paddy field influenced by market price.Agricultural development has caused severe wetlands degradation both in area and functionality,and still being the major threads for wetlands sustainable development.Several suggestions concerning the future land use policy formulation and wetlands sustainability were proposed.They are adjusting the‘food first’agricultural policy,reinforce management for wetlands nature reserves,creating infrastructure for the rational use of surface and groundwater,harnessing the degraded cultivated land. 展开更多
关键词 Baoqing COUNTY CROPLAND GEOGRAPHIC Information System(GIS) Remote Sensing(RS) WETLANDS
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Exceptional points of any order in a single, lossy waveguide beam splitter by photon-numberresolved detection
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作者 MARIO AQUIROZ-JUáREZ ARMANDO PEREZ-LEIJA +5 位作者 KONRAD TSCHERNIG BLAS MRODRíGUEZ-LARA OMAR SMAGA?A-LOAIZA KURT BUSCH YOGESH NJOGLEKAR ROBERTO DE JLEóN-MONTIEL 《光子学研究:英文版》 CSCD 2019年第8期862-867,共6页
Exceptional points(EPs) are degeneracies of non-Hermitian operators where, in addition to the eigenvalues, the corresponding eigenmodes become degenerate. Classical and quantum photonic systems with EPs have attracted... Exceptional points(EPs) are degeneracies of non-Hermitian operators where, in addition to the eigenvalues, the corresponding eigenmodes become degenerate. Classical and quantum photonic systems with EPs have attracted tremendous attention due to their unusual properties, topological features, and an enhanced sensitivity that depends on the order of the EP, i.e., the number of degenerate eigenmodes. Yet, experimentally engineering higher-order EPs in classical or quantum domains remain an open challenge due to the stringent symmetry constraints that are required for the coalescence of multiple eigenmodes. Here, we analytically show that the number-resolved dynamics of a single, lossy waveguide beam splitter, excited by N indistinguishable photons and post-selected to the N-photon subspace, will exhibit an EP of order N+1. By using the well-established mapping between a beam splitter Hamiltonian and the perfect state transfer model in the photon-number space,we analytically obtain the time evolution of a general N-photon state and numerically simulate the system’s evolution in the post-selected manifold. Our results pave the way toward realizing robust, arbitrary-order EPs on demand in a single device. 展开更多
关键词 EP Exceptional points photon-numberresolved DETECTION
Kyanite far from equilibrium dissolution rate at 0-22 ℃ and pH of 3.5-7.5
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作者 Yilun Zhang Donald J.Rimstidt +1 位作者 Yi Huang Chen Zhu 《中国地球化学学报:英文版》 EI CAS CSCD 2019年第4期472-480,共9页
Kyanite is an important and slow-dissolving mineral. Earlier work has measured its dissolution rate at high temperature and acidic pH, but experimental measurements at low temperature and near neutral p H were lacking... Kyanite is an important and slow-dissolving mineral. Earlier work has measured its dissolution rate at high temperature and acidic pH, but experimental measurements at low temperature and near neutral p H were lacking. The rate equation by Palandri and Kharaka(A compilation of rate parameters of water–mineral interaction kinetics for application to geochemical modeling. US Geological Survey, Open File Report 2004-1068, 2004) indicates that the rate of kyanite dissolution at room temperature and near neutral pH is on the order of 10^-17 mol m^-2 s^-1, orders of magnitudes slower than most common silicate minerals such as albite and quartz. This study used an externallystirred mixed-flow reactor, which allows high solid:solution ratios, to measure the dissolution rate of kyanite at 0–22 ℃ and pH of 3.5–7.5. The measured dissolution rate of kyanite is 4.6–7.6 9 10-13 mol m^-2 s^-1 at 22℃, and the apparent activation energy is 73.5 kJ mol^-1. This dissolution rate is close to the rate of quartz dissolution and four orders of magnitude faster than the prediction by rate equation of Palandri and Kharaka(2004).Based on our new experimental data, we recommend the following rate equation for modeling the dissolution of kyanite at ambient temperatures.r=ke(-Ea)/R(1/T-1/(298.15))where k = 5.08 9 10-13 mol m^-2 s^-1, and Ea= 73.5 kJ mol^-1. Review of literature data(Carroll in The dissolution behavior of corundum, kaolinite, and andalusite: a surface complex reaction model for the dissolution of aluminosilicate minerals in diagenetic and weathering environs. Dissertation, Northwestern University, 1989) led to a recommended rate equation for andalusite as for T = 25℃ and pH = 2–10:r=k1aH+^n1+k2+k3aH^+^n3where k1= 4.04 9 10^-10 mol m^-2 s^-1, k2= 7.95×10^-10 mol m^-2 s^-1, k3= 1.01×10^-17 mol m^-2 s^-1, n1= 1.2 and n3=-0.6. 展开更多
关键词 KINETICS KYANITE REACTION rates Mixed-flow REACTOR
Middle East respiratory syndrome coronavirus in pediatrics: a report of seven cases from Saudi Arabia
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作者 Sarah H. Alfaraj Jaffar A. Al-Tawfiq +1 位作者 Talal A. Altuwaijri Ziad A. Memish 《医学前沿:英文版》 CAS CSCD 2019年第1期126-130,共5页
Infection with Middle East respiratory syndrome coronavirus (MERS-CoV) emerged in 2012 as an important respiratory disease with high fatality rates of 40%—60%. Despite the increased number of cases over subsequent ye... Infection with Middle East respiratory syndrome coronavirus (MERS-CoV) emerged in 2012 as an important respiratory disease with high fatality rates of 40%—60%. Despite the increased number of cases over subsequent years, the number of pediatric cases remained low. A review of studies conducted from June 2012 to April 19, 2016 reported 31 pediatric MERS-CoV cases. In this paper, we present the clinical and laboratory features of seven patients with pediatric MERS. Five patients had no underlying medical illnesses, and three patients were asymptomatic. Of the seven cases, four (57%) patients sought medical advice within 1-7 days from the onset of symptoms. The three other patients (43%) were asymptomatic and were in contact with patients with confirmed diagnosis of MERS-CoV. The most common presenting symptoms were fever (57%), cough (14%), shortness of breath (14%), vomiting (28%), and diarrhea (28%). Two (28.6%) patients had platelet counts of < 150 ×10^9/L, and one patient had an underlying end-stage renal disease. The remaining patients presented with normal blood count, liver function, and urea and creatinine levels. The documented MERS-CoV Ct values were 32 38 for four of the seven cases. Two patients (28.6%) had abnormal chest radiographic findings of bilateral infiltration. One patient (14.3%) required ventilator support, and two patients (28.6%) required oxygen supplementation. All the seven patients were discharged without complications. 展开更多
关键词 Middle East RESPIRATORY SYNDROME CORONAVIRUS MERS-CoV pregnancy PEDIATRICS
Pharmacokinetic,Physicochemical and Medicinal Properties of N-glycoside Anti-cancer Agent More Potent than 2-Deoxy-D-Glucose in Lung Cancer Cells 预览
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作者 Fidelis Toloyi Ndombera Geoffrey K.K.Maiyoh Vivian C.Tuei 《药剂与药理学:英文版》 2019年第4期165-176,共12页
Acetylated N-xyloside of 1-naphthylamine(K8A)has been shown to be more potent than 2-deoxy-D-glucose in lung cancer cells and has therapeutic potential for further drug development.In this paper we evaluate and report... Acetylated N-xyloside of 1-naphthylamine(K8A)has been shown to be more potent than 2-deoxy-D-glucose in lung cancer cells and has therapeutic potential for further drug development.In this paper we evaluate and report cytotoxicity,pharmacokinetic,physicochemical and medicinal properties of this D-Xylose derivative(K8A)as a lead anticancer agent with greater therapeutic potential than 2-deoxy-D-glucose(2-DG).2-DG has been in clinical trials for treatment of solid tumors and other types of cancer.We demonstrate using virtual tools that K8A has better“drug-likeness”than 2-DG and does not violate any Lipinski,Ghose,Veber,Egan or Muegge rules.On the other hand,2-DG violates Ghose and Muegge rules.A“BOILEDegg evaluation”,predicts that K8A has higher gastrointestinal absorption(HIA)than 2-DG and is not effluxed by P-glycoprotein(P-gp).Additionally,K8A does not penetrate the blood brain barrier(BBB)and is not a substrate of most Cytochrome P450(CYP)enzymes.Importantly,K8A did not show false positive alert from PAINS screening enabling us to narrow down and rule out false targets.Importantly,K8A is more potent than 2-DG in H1299 and A549 lung cancer cells. 展开更多
关键词 ANTICANCER agent N-glycoside 2-deoxy-D-glucose pharmacokinetics lung cancer
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A Survey of Model Predictive Control Methods for Traffic Signal Control 预览
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作者 Bao-Lin Ye Weimin Wu +4 位作者 Keyu Ruan Lingxi Li Tehuan Chen Huimin Gao Yaobin Chen 《自动化学报:英文版》 CSCD 2019年第3期623-640,共18页
Enhancing traffic efficiency and alleviating (even circumventing) traffic congestion with advanced traffic signal control (TSC) strategies are always the main issues to be addressed in urban transportation systems. Si... Enhancing traffic efficiency and alleviating (even circumventing) traffic congestion with advanced traffic signal control (TSC) strategies are always the main issues to be addressed in urban transportation systems. Since model predictive control (MPC) has a lot of advantages in modeling complex dynamic systems, it has been widely studied in traffic signal control over the past 20 years. There is a need for an in-depth understanding of MPC-based TSC methods for traffic networks. Therefore, this paper presents the motivation of using MPC for TSC and how MPC-based TSC approaches are implemented to manage and control the dynamics of traffic flows both in urban road networks and freeway networks. Meanwhile, typical performance evaluation metrics, solution methods, examples of simulations, and applications related to MPC-based TSC approaches are reported. More importantly, this paper summarizes the recent developments and the research trends in coordination and control of traffic networks with MPC-based TSC approaches. Remaining challenges and open issues are discussed towards the end of this paper to discover potential future research directions. 展开更多
关键词 AUTONOMOUS vehicles coordination CONTROL mixed INTEGER PROGRAMMING model PREDICTIVE CONTROL system decomposition TRAFFIC flow models TRAFFIC signal CONTROL
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Exploring the efficacy of natural products in alleviating Alzheimer's disease 预览
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作者 Prajakta Deshpande Neha Gogia Amit Singh 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第8期1321-1329,共9页
Alzheimer's disease (hereafter AD) is a progressive neurodegenerative disorder that affects the central nervous system. There are multiple factors that cause AD, viz., accumulation of extracellular Amyloid-beta 42... Alzheimer's disease (hereafter AD) is a progressive neurodegenerative disorder that affects the central nervous system. There are multiple factors that cause AD, viz., accumulation of extracellular Amyloid-beta 42 plaques, intracellular hyper-phosphorylated Tau tangles, generation of reactive oxygen species due to mitochondrial dysfunction and genetic mutations. The plaques and tau tangles trigger aberrant signaling, which eventually cause cell death of the neurons. As a result, there is shrinkage of brain, cogrdtive defects, behavioral and psychological problems. To date, there is no direct cure for AD. Thus, scientists have been testing various strategies like screening for the small inhibitor molecule library or natural products that may block or prevent onset of AD. Historically, natural products have been used in many cultures for the treatment of various diseases. The research on natural products have gained importance as the active compounds extracted from them have medicinal values with reduced side effects, and they are bioavailable. The natural products may target the proteins or members of signaling pathways that get altered in specific diseases. Many natural products are being tested in various animal model systems for their role as a potential therapeutic target for AD, and to address questions about how these natural products can rescue AD or other neurodegenerative disorders. Some of these products are in clinical trials and results are promising because of their neuroprotective, anti-inflammatory, antioxidant, anti-amyloidogenic, anticholinesterase activities and easy availability. This review summarizes the use of animal model systems to identify natural products, which may serve as potential therapeutic targets for AD. 展开更多
关键词 Alzheimer's disease AMYLOID-BETA 42 natural products Lunasin NEUROPROTECTIVE anti-inflatnmation antioxidant DROSOPHILA cell DEATH NEURODEGENERATION
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Evaluation of a locked nucleic acid form of antisense oligo targeting HIF-1α in advanced hepatocellular carcinoma 预览
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作者 Jennifer Wu Merly Contratto +5 位作者 Krishna P Shanbhogue Gulam A Manji Bert H O’Neil Anne Noonan Robert Tudor Ray Lee 《世界临床肿瘤学杂志(英文版)》 2019年第3期149-160,共12页
BACKGROUND Hypoxia-inducible factor 1α(HIF-1α) is a gene that regulates tumor survival,neovascularization and invasion. Overexpression of HIF-1α correlates with poor prognosis in hepatocellular carcinoma(HCC). RO70... BACKGROUND Hypoxia-inducible factor 1α(HIF-1α) is a gene that regulates tumor survival,neovascularization and invasion. Overexpression of HIF-1α correlates with poor prognosis in hepatocellular carcinoma(HCC). RO7070179 is a HIF-1α inhibitor that decreases HIF-1α mRNA and its downstream targets, it could be a potential treatment in HCC.AIM To evaluate safety and preliminary activity of RO7070179 in patients with previously treated HCC, with focus on a patient with prolonged response to RO7070179.METHODS In the preclinical study of RO7070179 in a HCC xenograft model, the mice wereseparated into 4 groups with each group received doses of 0, 3, 10 and 30 mg/kg for total 10 doses. HCC patients who failed at least one line of systemic treatment,received RO7070179 as a weekly infusion, each cycle is 6 wk. We evaluated the safety and HIF-1α mRNA levels of RO7070179.RESULTS Preclinical evaluation of RO7070179 in orthotopic HCC xenograft model showed no significant differences in HCC tumor weight between the 3 and 10 mg/kg groups. However, dose of 10 mg/kg of RO7070179, has shown 76% reduction of the amount of HIF-1α mRNA in HCC tissue. In the phase 1 b study of RO7070179 in previously treated HCC patients, 8 out of 9 were evaluable: 1 achieved PR and1 SD. The patient with PR responded after 2 cycles treatments, which has been maintained for 12 cycles. This patient also showed reduction in perfusion of dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI) after 1 cycle of treatment. After 1 cycle of treatment, both patients with PR and SD showed decrease in HIF-1α mRNA at the root of biopsies(each biopsy was divided into 2 specimens, the tip and the root).CONCLUSION RO7070179 can reduce HIF-1α mRNA level in HCC patients with SD or PR. It is well tolerated at 10 mg/kg, with transaminitis as the dose of increased toxicity.This study indicates that RO7070179 might benefit HCC patients, and an early signal for clinical benefit can potentially be predicted through changes in either m RNA level or DCE-MRI withi 展开更多
关键词 HEPATOCELLULAR carcinoma Hypoxia-inducible factor RO7070179 Superresponder Dynamic contrast-enhanced-magnetic RESONANCE imaging
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Mathematical Analysis of the Jin-Neelin Model of El Ni?o-Southern-Oscillation
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作者 Yining CAO Mickael D.CHEKROUN +1 位作者 Aimin HUANG Roger TEMAM 《数学年刊:B辑英文版》 SCIE CSCD 2019年第1期1-38,共38页
The Jin-Neelin model for the El Ni?o-Southern Oscillation (ENSO for short)is considered for which the authors establish existence and uniqueness of global solutions in time over an unbounded channel domain.The result ... The Jin-Neelin model for the El Ni?o-Southern Oscillation (ENSO for short)is considered for which the authors establish existence and uniqueness of global solutions in time over an unbounded channel domain.The result is proved for initial data and forcing that are sufficiently small.The smallness conditions involve in particular key physical pa- rameters of the model such as those that control the travel time of the equatorial waves and the strength of feedback due to vertical-shear currents and upwelling;central mechanisms in ENSO dynamics. From the mathematical view point,the system appears as the coupling of a linear shallow water system and a nonlinear heat equation.Because of the very different nature of the two components of the system,the authors find it convenient to prove the existence of solution by semi-discretization in time and utilization of a fractional step scheme.The main idea consists of handling the coupling between the oceanic and temperature components by dividing the time interval into small sub-intervals of length k and on each sub-interval to solve successively the oceanic component,using the temperature T calculated on the previous sub-interval,to then solve the sea-surface temperature (SST for short)equation on the current sub-interval.The passage to the limit as k tends to zero is ensured via a priori estimates derived under the aforementioned smallness conditions. 展开更多
关键词 EL Ni?o-Southern OSCILLATION Coupled nonlinear hyperbolic-parabolic systems FRACTIONAL step method SEMIGROUP theory
Detecting white matter alterations in multiple sclerosis using advanced diffusion magnetic resonance imaging 预览
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作者 Sourajit M. Mustafi Jaroslaw Harezlak +4 位作者 Chandana Kodiweera Jennifer S. Randolph James C. Ford Heather A. Wishart Yu-Chien Wu 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第1期114-123,共10页
关键词 声成像 硬化 多重 磁性 检测 度量标准 空间成像 结构改变
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Effects of systematic octupole coupling resonances 预览
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作者 Hong-Jin Zeng Shyh-Yuan Lee +4 位作者 Shu-Xin Zheng Hong-Juan Yao Xue-Wu Wang Hui Ning Xiao-Jun Meng 《核技术:英文版》 SCIE CAS CSCD 2019年第7期10-15,共6页
The Xi’an proton accelerator facility synchrotron lattice has a systematic fourth-order resonance. The systematic octupole component in dipole magnets is found to have no adverse effect on the dynamic aperture in mul... The Xi’an proton accelerator facility synchrotron lattice has a systematic fourth-order resonance. The systematic octupole component in dipole magnets is found to have no adverse effect on the dynamic aperture in multiparticle tracking. The frequency map shows particles locked onto the 2v x 2v z-0 resonance. However, we will show that the instantaneous betatron tunes can vary widely around the resonance line for particles locked onto the resonance. 展开更多
关键词 OCTUPOLE COUPLING RESONANCE DYNAMIC APERTURE XiPAF
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Spontaneous fungal peritonitis:Micro-organisms,management and mortality in liver cirrhosis-A systematic review 预览
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作者 Tooba Tariq Furqan B Irfan +3 位作者 Mehdi Farishta Brian Dykstra Eric Martin Sieloff Archita P Desai 《世界肝病学杂志:英文版(电子版)》 2019年第7期596-606,共11页
BACKGROUND Spontaneous peritonitis is an infection of ascitic fluid without a known intraabdominal source of infection. spontaneous fungal peritonitis (SFP) is a potentially fatal complication of decompensated cirrhos... BACKGROUND Spontaneous peritonitis is an infection of ascitic fluid without a known intraabdominal source of infection. spontaneous fungal peritonitis (SFP) is a potentially fatal complication of decompensated cirrhosis, defined as fungal infection of ascitic fluid in the presence of ascitic neutrophil count of greater than 250 cells/mL. AIM To determine the prevalence of fungal pathogens, management and outcomes (mortality) of SFP in critically ill cirrhotic patients. METHODS Studies were identified using PubMed, EMBASE, Cochrane Central Register of Controlled Trials and Scopus databases until February 2019. Inclusion criteria included intervention trials and observation studies describing the association between SFP and cirrhosis. The primary outcome was in-hospital, 1-mo, and 6- mo mortality rates of SFP in cirrhotic patients. Secondary outcomes were fungal microorganisms identified and in hospital management by anti-fungal medications. The National Heart, Lung and Blood Institute quality assessment tools were used to assess internal validity and risk of bias for each included study. RESULTS Six observational studies were included in this systematic review. The overall quality of included studies was good. A meta-analysis of results could not be performed because of differences in reporting of outcomes and heterogeneity of the included studies. There were 82 patients with SFP described across all the included studies. Candida species, predominantly Candida albicans was the fungal pathogen in majority of the cases (48%-81.8%) followed by Candida krusei (15%- 25%) and Candida glabrata (6.66%-20%). Cryptococcus neoformans (53.3%) was the other major fungal pathogen. Antifungal therapy in SFP patients was utilized in 33.3% to 81.8% cases. The prevalence of in hospital mortality ranged from 33.3% to 100%, whereas 1-mo mortality ranged between 50% to 73.3%. CONCLUSION This systematic review suggests that SFP in end stage liver disease patient is associated with high mortality both in the hospital and at 1-mo, and th 展开更多
关键词 SPONTANEOUS FUNGAL PERITONITIS Bacterial PERITONITIS Liver CIRRHOSIS Critical
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Unlocked disinfection by-product formation potential upon exposure of swimming pool water to additional stimulants
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作者 Alvyn P.Berg Ting-An Fang Hao L.Tang 《中国环境科学与工程前沿:英文版》 SCIE EI CAS CSCD 2019年第1期111-118,共8页
Anthropogenic organics are known to be responsible for the formation of harmful disinfection byproducts (DBPs) in swimming pool water (SPW). The research explored an important scenario of SPW with no additional anthro... Anthropogenic organics are known to be responsible for the formation of harmful disinfection byproducts (DBPs) in swimming pool water (SPW). The research explored an important scenario of SPW with no additional anthropogenic organic input. With stimulations by residual chlorine or additional chlorine and extended incubation, the formation of DBPs, especially chlorofonn, was significantly induced. Similar observations were found by investigating synthetic SPW made with sweat and urine. The presence of urine led to a massive fbmiation of chloroform, as noted by an approximate 19-fbld increase after 165-day incubation with a shock chlorine dose. The research suggests that consistent residual chlorine and long water retention as two typical features of SPW could unlock the DBP fbnnation potential of anthropogenic organics. Thus, limiting the introduction of anthropogenic organics may not have an immediate effect on reducing DBP levels, because their reactions with chlorine can be slow and long-lasting. Pool management should prioritize on control of urine and improving air ventilation. This work is useful to deepen understandings about DBP formation in SPW and provide implications for pool management and prospective legislation. 展开更多
关键词 TRIHALOMETHANES Haloacetic acids CHLOROFORM Residual chlorine ANTHROPOGENIC ORGANICS SWIMMING pool water
Heterogeneous sea-level rises along coastal zones and small islands
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作者 Guoshuai Li Xin Li +5 位作者 Tandong Yao Tao Che Hong Yang Mingguo Ma Haipeng Zhao Xiaoduo Pan 《科学通报:英文版》 SCIE EI CSCD 2019年第11期748-755,共8页
Coastal zones and many small islands are highly susceptible to sea-level rise(SLR). Coastal zones have a large exposed population and integrated high-value assets, and islands provide diverse ecosystem services to mil... Coastal zones and many small islands are highly susceptible to sea-level rise(SLR). Coastal zones have a large exposed population and integrated high-value assets, and islands provide diverse ecosystem services to millions of people worldwide. The coastal zones and small islands affected by SLR are likely to suffer from submergence, flooding and erosion in the future. However, very few studies have addressed the heterogeneity in SLR changes and the potential risk to coastal zones and small islands. Here we used the mean sea level(MSL) derived from satellite altimetry data to analyse the trends and accelerations of SLRs along global coastal zones and small islands. We found that except for the Antarctic coastal zone, the annual MSL within 50 km of the coasts presented an increasing trend of 3.09 ± 0.13 mm a^-1 but a decreasing acceleration of -0.02 ± 0.02 mm a^-2 from 1993 to 2017. The highest coastal MSL trend of3.85 ± 0.60 mm a^-1 appeared in Oceania, and the lowest trend of 2.32 ± 0.37 mm a^-1 occured in North America. Africa, North America and South America showed acceleration trends, and Eurasia, Australia and Oceania had deceleration trends. Further, MSLs around global small islands reflected an increasing trend with a rate of 3.01 ± 0.16 mm a^-1 but a negative acceleration of -0.02 ± 0.02 mm a^-2. Regional heterogeneity in the trends and accelerations of MSLs along the coasts and small islands suggests that stakeholders should take discriminating precautions to cope with future disadvantageous impacts of the SLR. 展开更多
关键词 SEA-LEVEL RISE COASTAL ZONES Small ISLANDS HETEROGENEITY
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