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Sensitivity of diagnosis of spontaneous bacterial peritonitis is higher with the automated cell count method
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作者 Juan G Acevedo-Haro Waddah Mohamed +8 位作者 Prebashan Moodley Oliver Bendall Kris Bennett Nigel Keelty Sally Chan Sam Waddy Joanne Hosking Wayne Thomas Robert Tilley 《World Journal of Hepatology》 2024年第11期1265-1281,共17页
BACKGROUND Spontaneous bacterial peritonitis(SBP)is one of the most important complications of patients with liver cirrhosis entailing high morbidity and mortality.Making an accurate early diagnosis of this infection ... BACKGROUND Spontaneous bacterial peritonitis(SBP)is one of the most important complications of patients with liver cirrhosis entailing high morbidity and mortality.Making an accurate early diagnosis of this infection is key in the outcome of these patients.The current definition of SBP is based on studies performed more than 40 years ago using a manual technique to count the number of polymorphs in ascitic fluid(AF).There is a lack of data comparing the traditional cell count method with a current automated cell counter.Moreover,current international guidelines do not mention the type of cell count method to be employed and around half of the centers still rely on the traditional manual method.AIM To compare the accuracy of polymorph count on AF to diagnose SBP between the traditional manual cell count method and a modern automated cell counter against SBP cases fulfilling gold standard criteria:Positive AF culture and signs/symptoms of peritonitis.METHODS Retrospective analysis including two cohorts:Cross-sectional(cohort 1)and case-control(cohort 2),of patients with decompensated cirrhosis and ascites.Both cell count methods were conducted simultaneously.Positive SBP cases had a pathogenic bacteria isolated on AF and signs/symptoms of peritonitis.RESULTS A total of 137 cases with 5 positive-SBP,and 85 cases with 33 positive-SBP were included in cohort 1 and 2,respectively.Positive-SBP cases had worse liver function in both cohorts.The automated method showed higher sensitivity than the manual cell count:80%vs 52%,P=0.02,in cohort 2.Both methods showed very good specificity(>95%).The best cutoff using the automated cell counter was polymorph≥0.2 cells×10^(9)/L(equivalent to 200 cells/mm^(3))in AF as it has the higher sensitivity keeping a good specificity.CONCLUSION The automated cell count method should be preferred over the manual method to diagnose SBP because of its higher sensitivity.SBP definition,using the automated method,as polymorph cell count≥0.2 cells×10^(9)/L in AF would need to be considered in patients admitted with decompensated cirrhosis. 展开更多
关键词 Spontaneous bacterial peritonitis DIAGNOSIS CIRRHOSIS Bacterial infection Automated cell count method Manual cell count method Ascitic fluid
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Modified Model of Crack Tip Stress Field Considering Dislocation Slip Accumulation and Crack Tip Blunting 被引量:1
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作者 Jian Li Bing Yang +4 位作者 Shuancheng Wang M.N.James Shoune Xiao Tao Zhu Guangwu Yang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第2期327-340,共14页
This study uses the digital image correlation technique to measure the crack tip displacement field at various crack lengths in U71MnG rail steel,and the interpolated continuous displacement field was obtained by fitt... This study uses the digital image correlation technique to measure the crack tip displacement field at various crack lengths in U71MnG rail steel,and the interpolated continuous displacement field was obtained by fitting with a back propagation(BP)neural network.The slip and stacking of dislocations affect crack initiation and growth,leading to changes in the crack tip field and the fatigue characteristics of crack growth.The Christopher-James-Patterson(CJP)model describes the elastic stress field around a growing fatigue crack that experiences plasticity-induced shielding.In the present work,this model is modified by including the effect of the dislocation field on the plastic zone of the crack tip and hence on the elastic field by introducing a plastic flow factorρ,which represents the amount of blunting of the crack tip.The Levenberg-Marquardt(L-M)nonlinear least squares method was used to solve for the stress intensity factors.To verify the accuracy of this modified CJP model,the theoretical and experimental plastic zone errors before and after modification were compared,and the variation trends of the stress intensity factors and the plastic flow factorρwere analysed.The results show that the CJP model,with the introduction ofρ,exhibits a good blunting trend.In the low plasticity state,the modified model can accurately describe the experimental plastic zone,and the modified stress intensity factors are more accurate,which proves the effectiveness of dislocation correction.This plastic flow correction provides a more accurate crack tip field model and improves the CJP crack growth relationship. 展开更多
关键词 Digital image correlation Back propagation neural network Plastic zone CJP model Dislocation field
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Geochronology,Mineralogy,and Geochemistry of the Tonsteins from the Permo–Carboniferous Benxi Formation,Ordos Basin,North China Craton 被引量:1
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作者 WANG Luojing LÜDawei +5 位作者 ZHANG Zhihui James C.HOWER Munira RAJI ZHANG Yushuai SHEN Yangyang GAO Jie 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第5期1355-1371,共17页
Tonstein layers are found worldwide in the Permo-Carboniferous coal-bearing strata.This study investigates the geochronology,mineralogy,and geochemistry of four tonstein samples from the Permo-Carboniferous Benxi Form... Tonstein layers are found worldwide in the Permo-Carboniferous coal-bearing strata.This study investigates the geochronology,mineralogy,and geochemistry of four tonstein samples from the Permo-Carboniferous Benxi Formation,Ordos Basin,North China Craton(NCC).The typical features of the studied tonsteins include thin beds,lateral continuity,angular quartz grains,and euhedral zircons with similar U-Pb ages,indicating a significant pyroclastic origin.In addition,the tonstein samples have low TiO_(2)/Al_(2)O_(3)ratios(<0.02)and rare earth elements and yttrium(REY)concentrations with obvious negative Eu anomalies,indicating that the tonsteins have a felsic magma origin.Moreover,compared with the mean composition of clay shale,the studied tonsteins are characterized by high concentrations of the elements Nb and Ta,which may affect the concentration of the corresponding elements in surrounding coal seams.The zircon U-Pb ages of the tonsteins(293.9-298.8 Ma)provide a precise chronological framework on the Benxi Formation in the Ordos Basin,constraining the Gzhelian-Aselian stages.The tonsteins were probably sourced from arc volcanism along the western margin of the NCC during the early Permian,implying that the Alxa Terrane had not amalgamated with the NCC at that time. 展开更多
关键词 tonsteins GEOCHEMISTRY Permo–Carboniferous North China Craton
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Runx2 regulates peripheral nerve regeneration to promote Schwann cell migration and re-myelination 被引量:1
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作者 Rong Hu Xinpeng Dun +1 位作者 Lolita Singh Matthew C.Banton 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1575-1583,共9页
Runx2 is a major regulator of osteoblast differentiation and function;however,the role of Runx2 in peripheral nerve repair is unclea r.Here,we analyzed Runx2expression following injury and found that it was specifical... Runx2 is a major regulator of osteoblast differentiation and function;however,the role of Runx2 in peripheral nerve repair is unclea r.Here,we analyzed Runx2expression following injury and found that it was specifically up-regulated in Schwann cells.Furthermore,using Schwann cell-specific Runx2 knocko ut mice,we studied peripheral nerve development and regeneration and found that multiple steps in the regeneration process following sciatic nerve injury were Runx2-dependent.Changes observed in Runx2 knoc kout mice include increased prolife ration of Schwann cells,impaired Schwann cell migration and axonal regrowth,reduced re-myelination of axo ns,and a block in macrophage clearance in the late stage of regeneration.Taken together,our findings indicate that Runx2 is a key regulator of Schwann cell plasticity,and therefore peripheral nerve repair.Thus,our study shows that Runx2 plays a major role in Schwann cell migration,re-myelination,and peripheral nerve functional recovery following injury. 展开更多
关键词 macrophage clearance MIGRATION peripheral nerve injury regeneration re-myelination RUNX2 Schwann cells
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青海喇家遗址极可能由地震导致的砂土液化泥流造成:“12·18”积石山地震的启示
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作者 李俊磊 张绪教 +5 位作者 鱼海麟 王一凡 张向格 李秋蓉 李彩虹 张丽蕾 《现代地质》 CAS CSCD 北大核心 2024年第1期248-259,共12页
形成于3900年前的青海省民和县喇家遗址,号称“东方庞贝”,是一处举世闻名的灾难遗址,但其成因争论由来已久、悬而未决。学者提出的多种“洪水成因”之说,已深入民众之心,但这次灾难事件真的和洪水有关么?2023年12月18日甘肃积石山县的... 形成于3900年前的青海省民和县喇家遗址,号称“东方庞贝”,是一处举世闻名的灾难遗址,但其成因争论由来已久、悬而未决。学者提出的多种“洪水成因”之说,已深入民众之心,但这次灾难事件真的和洪水有关么?2023年12月18日甘肃积石山县的6.2级地震的震中距喇家遗址仅16 km,不仅使喇家遗址博物馆损坏严重,而且触发的泥流在离遗址仅5 km处的民和县中川乡金田村和草滩村,造成了民房和村民被直接掩埋的灭顶之灾,可能是喇家灾难遗址形成过程的重现,成为对比研究喇家遗址成因的重要实证材料。通过对此次地震灾害的野外实地调查和综合研究,或许能解开喇家遗址成因之谜。积石山地震使黄土之下古河床砾石层中地下水沿地表破裂喷出上涌,进而造成黄土液化并顺冲沟快速往下游流动形成泥流,流经草滩村、金田村时泥流遇阻,漫出冲沟将部分房屋冲毁甚至导致村民被掩埋。特殊的地层结构及富集的地下水,在地震的触发之下造成砂土液化并形成泥流,是造成中川乡地震灾害的重要原因。现场调查表明,草滩村一家五口被掩埋的悲剧,并非典型的“砂涌”造成,更无“洪水”的痕迹,而是地震的次生泥流灾害所致。将今论古,结合喇家遗址的文化遗存保存状况及沉积物特征进一步推断,喇家遗址的形成可能与强降雨形成的山间洪流无关,更不是由所谓的“大洪水”造成的。3900年前的古地震及其造成的砂土液化和快速流动的泥流,极可能是造成喇家遗址瞬时灾难的主要成因。 展开更多
关键词 喇家遗址 积石山地震 液化泥流 瞬时灾难 拉脊山北缘断裂 黄河
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Study on TMD Control on Stability Improvement of Barge-Supported Floating Offshore Wind Turbine Based on the Multi-Island Genetic Algorithm 被引量:5
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作者 DING Qin-wei LI Chun +3 位作者 CHENG Shan-shan HAO Wen-xing HUANG Zhi-qian YU Wan 《China Ocean Engineering》 SCIE EI CSCD 2019年第3期309-321,共13页
A floating offshore wind turbine (FOWT) has a great potential in producing renewable energy as offshore wind resource is rich in deep sea area (water deeper than 60 m) where fixed foundations are cost-effective or dep... A floating offshore wind turbine (FOWT) has a great potential in producing renewable energy as offshore wind resource is rich in deep sea area (water deeper than 60 m) where fixed foundations are cost-effective or deployable. However, compared with a fixed-bottom installation, FOWT has to suffer more extreme loads due to its extra degrees of freedom. Therefore, the stability of an FOWT is a key challenge in exploiting offshore deep-water wind. Focusing on the stability of barge-type FOWT, this paper is to investigate the effect of passive structural control by equipping a tuned mass damper (TMD) on the nacelle. The turbulent wind with sharp fluctuations is established both in velocity and inflow direction based on standard Kaimal turbulence spectrum as suggested in the standard IEC61400-2. The irregular wave is generated according to the Pierson-Moskowitz spectrum. The dynamic structural characteristics of FOWT are calculated based on the fully coupled aero-hydro-servo-elastic solver FAST. Evidence has shown that the proposed method of the nacelle-based TMD is effective in controlling stability of an FOWT, as the sway and roll motions of barge and the side-side displacement of tower top decreased significantly. With the increase of mass, the side-side displacement of tower-top and the amplitude of roll motion of barge reveal a trend of increasing first and then decreasing. The stiffness and damping have little effect. Furthermore, the multi-island genetic optimization algorithm (MIGA) is employed to find globally optimum structural parameters (mass, stiffness and damping) of the TMD. The optimum structure parameters of TMD are achieved when the mass is 21393 kg, damping is 13635 N/(m/s) and stiffness is 6828 N/m. By adopting the optimized TMD, stability of roll motion of barge and side-side displacement of tower-top increase up to 53% and 50% respectively when compared with the normal TMD. The simulation results verify the validity and reliability of the proposed TMD control and the optimization methods. 展开更多
关键词 FOWT BARGE TMD MIGA wind wave STABILITY
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Sounds Synthesis with Slime Mould of Physarum Polycephalum 被引量:2
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作者 Eduardo R. Miranda Andrew Adamatzky Jeff Jones 《Journal of Bionic Engineering》 SCIE EI CSCD 2011年第2期107-113,共7页
This paper introduces a novel application of bionic engineering: a bionic musical instrument using Physarum polycephalum. Physarum polycephalum is a huge single cell with thousands of nuclei, which behaves like a gia... This paper introduces a novel application of bionic engineering: a bionic musical instrument using Physarum polycephalum. Physarum polycephalum is a huge single cell with thousands of nuclei, which behaves like a giant amoeba. During its foraging behavior this plasmodium produces electrical activity corresponding to different physiological states. We developed a method to render sounds from such electrical activity and thus represent spatio-temporal behavior of slime mould in a form apprehended auditorily. The electrical activity is captured by various electrodes placed on a Petri dish containing the cultured slime mold. Sounds are synthesized by a bank of parallel sinusoidal oscillators connected to the electrodes. Each electrode is responsible for one partial of the spectrum of the resulting sound. The behavior of the slime mould can be controlled to produce different timbres. 展开更多
关键词 Physarum polycephalum bionic musical instrument unconventional computing sound synthesis SONIFICATION
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Chemically Induced Mutants of <i>Brassica oleracea var. botrytis</i>Maintained Stable Resistance to Drought and Salt Stress after Regeneration and Micropropagation 被引量:1
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作者 Fazal Hadi Michael P. Fuller 《American Journal of Plant Sciences》 2013年第3期498-507,共10页
Investigation was made to confirm the stability of drought and salt stress tolerance in cauliflower (Brassica oleracea var.botrytis) mutants after regeneration and micropropagation. The N-nitroso-N-ethyleurea (NEU) an... Investigation was made to confirm the stability of drought and salt stress tolerance in cauliflower (Brassica oleracea var.botrytis) mutants after regeneration and micropropagation. The N-nitroso-N-ethyleurea (NEU) and N-nitroso-N-methylurea (NMU) induced mutants of cauliflower were created and screened for drought and salt stress tolerance. The highly tolerant mutants were selected, regenerated by tissue culture techniques, screened again for drought and salt tolerance under in-vitro and in-vivo conditions, correlated the response of in-vitro and in-vivo plants within a clone. Free proline levels in clones were correlated with stress tolerance. Results confirmed the persistence of mutations in clones with enhanced resistance levels to stresses over control plants. The regenerated in-vitro and in-vivo plants within a clone showed a positive significant correlation for drought (R2 = 0.663) and salt (R2 = 0.647) resistance that confirms the stability of mutation in clones after generations. Proline showed a positive and significant correlation with drought (R2 = 0.524) and salt (R2 = 0.786) tolerance. Conclusively, drought and salt resistance can be successfully enhanced in cauliflower by chemical mutagenesis. Further molecular analysis is recommended to study these mutants. 展开更多
关键词 DROUGHT Salt Stress RESISTANCE Proline In-Vitro In-Vivo CAULIFLOWER
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Effect of zinc treatment on clinical outcomes in patients with liver cirrhosis:A systematic review and meta-analysis 被引量:1
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作者 Huey K Tan Adam Streeter +1 位作者 Matthew E Cramp Ashwin D Dhanda 《World Journal of Hepatology》 CAS 2020年第7期389-398,共10页
BACKGROUNDZinc is an essential trace element integral to many cellular and immune functions.Zinc deficiency is highly prevalent in patients with cirrhosis and related to diseaseseverity.AIMTo evaluate whether zinc sup... BACKGROUNDZinc is an essential trace element integral to many cellular and immune functions.Zinc deficiency is highly prevalent in patients with cirrhosis and related to diseaseseverity.AIMTo evaluate whether zinc supplementation improves clinical outcomes (diseaseseverity and mortality) in patients with cirrhosis.METHODSThis prospectively registered systematic review (PROSPERO reference:CRD42018118219) included all studies in Medline, Embase or Cochrane databasewith inclusion criteria of adult human studies, comparing zinc supplementationof at least 28 d with standard care or placebo in patients with cirrhosis. Mortalityand clinical severity score data were extracted. Random effects meta-analysescompared mortality at 6 mo and 2 years. Risk of bias was assessed using theNational Institutes of Health quality assessment tool.RESULTSSeven hundred and twelve articles were identified of which four were eligible.Zinc formulations and doses varied (elemental zinc 3.4-214 mg daily) for different intervention periods in patients with differing etiology and severity of cirrhosis.Two studies were considered to be at high risk of bias. There was no significantdifference in 6-mo mortality between patients treated with zinc versus controls[risk ratio 0.98 (0.90-1.05)]. Changes in severity scores were not reported in anystudy.CONCLUSIONZinc supplementation is not associated with reduced mortality in patients withcirrhosis. Findings are limited by the small number of eligible studies andsignificant heterogeneity in intervention and patient population. 展开更多
关键词 ZINC CIRRHOSIS MORTALITY
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Investigation of Wave-Structure Interaction Using State of the Art CFD Techniques 被引量:1
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作者 Jan Westphalen Deborah M. Greaves +6 位作者 Alison Raby Zheng Zheng Hu Derek M. Causon Clive G. Mingham Pourya Omidvar Peter K. Stansby Benedict D. Rogers 《Open Journal of Fluid Dynamics》 2014年第1期18-43,共26页
The suitability of computational fluid dynamics (CFD) for marine renewable energy research and development and in particular for simulating extreme wave interaction with a wave energy converter (WEC) is considered. Fu... The suitability of computational fluid dynamics (CFD) for marine renewable energy research and development and in particular for simulating extreme wave interaction with a wave energy converter (WEC) is considered. Fully nonlinear time domain CFD is often considered to be an expensive and computationally intensive option for marine hydrodynamics and frequency-based methods are traditionally preferred by the industry. However, CFD models capture more of the physics of wave-structure interaction, and whereas traditional frequency domain approaches are restricted to linear motions, fully nonlinear CFD can simulate wave breaking and overtopping. Furthermore, with continuing advances in computing power and speed and the development of new algorithms for CFD, it is becoming a more popular option for design applications in the marine environment. In this work, different CFD approaches of increasing novelty are assessed: two commercial CFD packages incorporating recent advances in high resolution free surface flow simulation;a finite volume based Euler equation model with a shock capturing technique for the free surface;and meshless Smoothed Particle Hydrodynamics (SPH) method. These different approaches to fully nonlinear time domain simulation of free surface flow and wave structure interaction are applied to test cases of increasing complexity and the results compared with experimental data. Results are presented for regular wave interaction with a fixed horizontal cylinder, wave generation by a cone in driven vertical motion at the free surface and extreme wave interaction with a bobbing float (The Manchester Bobber WEC). The numerical results generally show good agreement with the physical experiments and simulate the wave-structure interaction and wave loading satisfactorily. The grid-based methods are shown to be generally less able than the meshless SPH to capture jet formation at the face of the cone, the resolution of the jet being grid dependent. 展开更多
关键词 WAVE Loading WAVE Energy Wave-Structure Interaction Manchester Bobber CFD Physical Experiments FV CV-FE SPH Cartesian-Cut-Cell SPHysics AMAZON SC STAR CCM+ CFX
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Study on Vitalizing Port Operation at Ulsan Port: Focused on Main Port of Ulsan 被引量:1
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作者 Dal Won Kang Kyu-Seok Kwak Ki-Chan Nam 《Journal of Shipping and Ocean Engineering》 2014年第3期72-78,共7页
Ulsan port is the hugest industry-oriented port in South Korea. It has the third highest traffic volume of cargo, and also it has the most liquid bulk in Korea. However, on account of thoughtless development, there ar... Ulsan port is the hugest industry-oriented port in South Korea. It has the third highest traffic volume of cargo, and also it has the most liquid bulk in Korea. However, on account of thoughtless development, there are other cases like Ulsan port that liquid cargo and general cargo are simultaneously handled. The demurrage ratio takes up to 12.5% of probability on average. In 2010, it has less room at berths for liquid bulk than general cargo and it totally has 107% of processing ratio (throughput). This indicates that Ulsan port concentrates on liquid cargo more than general cargo depending on the characteristics of the port. This research suggests the effects as alternatives for efficiency and effectivity at both ports, Ulsan port and Pohang port in the case that the general cargo handled in Ulsan port is relocated to Pohang port in terms of the characteristics of products which Pohang port and its hinterland the most focused on. Namely, we estimate volume of relocated volume suitable for relocation in assumption that volume handled in Ulsan port is relocated to Pohang port scenario by scenario, analyze the effects of relocated volume, and suggest alternatives for vitalizing Ulsan port. 展开更多
关键词 Ulsan port port facilities HINTERLAND vitalization alternatives
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The Global Stratotype Section and Point (GSSP) for the base of the Holocene Series/Epoch (Quaternary System/Period) in the NGRIP ice core 被引量:3
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作者 Mike Walker Sigfus Johnsen +16 位作者 Sune Olander Rasmussen Jorgen-Peder Steffensen Trevor Popp Philip Gibbard Wim Hoek John Lowe John Andrews Svante Bjorck Les Cwynar Konrad Hughen Peter Kershaw Bernd Kromer Thomas Litt David J. Lowe Takeshi Nakagawa Rewi Newnham Jakob Schwander 《Episodes》 SCIE 2008年第2期264-267,共4页
The Greenland ice core from NorthGRIP (NGRIP) contains a proxy climate record across the Pleistocene-Holocene boundary of unprecedented clarity and resolution. Analysis of an array of physical and chemical parameter... The Greenland ice core from NorthGRIP (NGRIP) contains a proxy climate record across the Pleistocene-Holocene boundary of unprecedented clarity and resolution. Analysis of an array of physical and chemical parameters within the ice enables the base of the Holocene, as reflected in the first signs of climatic warming at the end of the Younger Dryas/Greenland Stadial 1 cold phase, to be located with a high degree of precision. 展开更多
关键词 地球 全新世 第四纪地质时代 周期
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The Global Boundary Stratotype Section and Point (GSSP) for the base of the Pliensbachian Stage (Lower Jurassic), Wine Haven, Yorkshire, UK 被引量:1
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作者 Christian Meister Martin Aberhan +10 位作者 Joachim Blau Jean-Louis Dommergues Susanne Feist-Burkhardt Ernie A. Hailwood Malcom Hart Stephen P. Hesselbos Mark W. Hounslow Mark Hylton Nicol Morton Kevin Page Greg D. Price 《Episodes》 SCIE 2006年第2期93-106,共14页
Following votes by the Pliensbachian Working Group, the Jurassic Subcommission and the International Commission on Stratigraphy, lUGS ratified the proposed Global Boundary Stratotype Section and Point (GSSP) for the... Following votes by the Pliensbachian Working Group, the Jurassic Subcommission and the International Commission on Stratigraphy, lUGS ratified the proposed Global Boundary Stratotype Section and Point (GSSP) for the base of the Pliensbachian Stage (Lower Jurassic) at the base of bed 73b in the Wine Haven section, Robin Hood's Bay, Yorkshire Coast, UK. This level contains the characteristic ammonite association Bifericeras donovani Dommergues and Meister and Apoderoceras sp. Complementary data include: a) Strontium-isotope stratigraphy, based on analysis of belemnites which yield a calcite 87Sr/^86Sr ratio for the boundary level of 0. 707425 and data supporting interpretation of continuous sedimentation; b) Belemnite oxygen-isotope data indicate a significant temperature drop (-5 ℃) across the boundary at this locality; c) A Transgressive Systems Tract (TST) initiated in the Aplanaturn Subzone (uppermost Sinemurian) continues into the Lowermost Pliensbachian (Taylori Subzone); it forms part of a transgressive facies cycle sensu Graciansky et al. (1998); d) The Upper Sinemurian to lowermost Plensbachian at Wine Haven section has a predominantly norreal magnetic polarity, but two discrete reversed polarity magnetozones are present. The first spans much of the latest Sinemurian Aplanatum Subzone. It terminates 〈0.5m below the Sinemurian-Pliensbachian boundary and may prove a valuable chronostratigraphic marker The second extends from the latest Oxynotum Subzone probably through to the lower part of the Raricostatum Subzone. 展开更多
关键词 普连斯巴奇阶 侏罗纪 GSSP 全球界线层型剖面点
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Is activation of GDNF/RET signaling the answer for successful treatment of Parkinson's disease?A discussion of data from the culture dish to the clinic
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作者 James A.Conway Edgar R.Kramer 《Neural Regeneration Research》 SCIE CAS CSCD 2022年第7期1462-1467,共6页
The neurotrophic signaling of glial cell line-derived neurotrophic factor(GDNF)with its canonical receptor,the receptor tyrosine kinase RET,coupled together with the GDNF family receptor alpha 1 is important for dopam... The neurotrophic signaling of glial cell line-derived neurotrophic factor(GDNF)with its canonical receptor,the receptor tyrosine kinase RET,coupled together with the GDNF family receptor alpha 1 is important for dopaminergic neuron survival and physiology in cell culture experiments and animal models.This prompted the idea to try GDNF/RET signaling as a therapeutic approach to treat Parkinson’s disease with the hallmark of dopaminergic cell death in the substantia nigra of the midbrain.Despite several clinical trials with GDNF in Parkinson’s disease patients,which mainly focused on optimizing the GDNF delivery technique,benefits were only seen in a few patients.In general,the endpoints did not show significant improvements.This suggests that it will be helpful to learn more about the basic biology of this fascinating but complicated GDNF/RET signaling system in the dopaminergic midbrain and about recent developments in the field to facilitate its use in the clinic.Here we will refer to the latest publications and point out important open questions in the field. 展开更多
关键词 Α-SYNUCLEIN clinical trials dopaminergic neurons glial cell line-derived neurotrophic factor GFRα1 gut-brain axis Nedd4 PARKIN Parkinson’s disease RET
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Free torsion of thin-walled structural members of open-and closed-sections
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作者 Long-yuan LI D.EASTERBROOK 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2014年第1期25-32,共8页
Free torsion of thin-walled structures of open- and closed-sections is a classical elastic mechanics problem, which, in literature, is often solved by the method of membrane analogy. The method of membrane analogy, ho... Free torsion of thin-walled structures of open- and closed-sections is a classical elastic mechanics problem, which, in literature, is often solved by the method of membrane analogy. The method of membrane analogy, however, can be only applied to structures of a single material. If the structure consists of both open- and closed-sections, the method of membrane analogy is difficult to be applied. In this paper, a new method is presented for solving the free torsion of thin-walled structures of open- and/or closed- sections with multiple materials. By utilizing a simple statically indeterminate concept, torsional equations are derived based on the equilibrium and compatibility conditions. The method presented here not only is very simple and easy to understand but also can be applied to thin-walled structures of combined open- and closed-sections with multiple materials. 展开更多
关键词 TORSION THIN-WALLED open-section closed-section shear flow shear stress
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Mathematical modelling of axonal microtubule bundles under dynamic torsion
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作者 J.Y.WU Hong YUAN L.Y.LI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2018年第6期829-844,共16页
Owing to its viscoelastic nature, axon exhibits a stress rate-dependent me- chanical behavior. An extended tension-shear chain model with Kelvin-Voigt viscoelas- ticity is developed to illustrate the micromechanical b... Owing to its viscoelastic nature, axon exhibits a stress rate-dependent me- chanical behavior. An extended tension-shear chain model with Kelvin-Voigt viscoelas- ticity is developed to illustrate the micromechanical behavior of the axon under dynamic torsional conditions. Theoretical closed-form expressions are derived to predict the de- formation, stress transfer, and failure mechanism between microtubule (MT) and tau protein while the axon is sheared dynamically. The results obtained from the present an- alytical solutions demonstrate how the MT-tau interface length, spacing between the tau proteins, and loading rate affect the mechanical properties of axon. Moreover, it is found that the MTs are more prone to rupture due to the contributions from the viscoelastic effects. Under the torsional force, the MTs are so long that the stress concentrates at the loaded end where axonal MTs will break. This MT-tau protein dynamics model can help to understand the underlying pathology and molecular mechanisms of axonal injury. Additionally, the emphasis of this paper is on the micromechanical behavior of axon, whereas this theoretical model can be equally applicable to other soft or hard tissues, owning the similar fibrous structure. 展开更多
关键词 TORSION BIOCOMPOSITE diffuse axonal injury (DAI) Kelvin-Voigt viscoelas-tic model dynamic response tension-shear chain model
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Measuring Quality of Economic Growth Incorporating Environment and Social Welfare:a Total Productivity Approach with an Application on China
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作者 SUN Yanyan DAI Changjun 《Journal of Donghua University(English Edition)》 EI CAS 2018年第5期411-417,共7页
By extending the traditional productivity theory,a new concept total productivity( TP) is introduced. Using a directional distance function approach,the concept is applied to measuring economic growth of 8 economic re... By extending the traditional productivity theory,a new concept total productivity( TP) is introduced. Using a directional distance function approach,the concept is applied to measuring economic growth of 8 economic regions of China covering an 18 years period( 1997—2014) and test its convergence. Results showed that TP grew at an average rate of 6. 6% per year led mainly by technical change( 6. 5%). When environmental undesirable outputs are included,the Middle Yellow River,Northwest and Southwest regions of China witnessed higher productivity changes. Results of the convergence analysis revealed that China had made progress in reducing regional imbalance in growth. Inclusion of undesirable output showed that the energy-saving emission reduction policies had speed up the convergence rate of TP and environment oriented productivity. However,China's welfare oriented productivity is still very low. 展开更多
关键词 undesirable OUTPUT directional DISTANCE function total productivity(TP) Malmquist-Luenberger PRODUCTIVITY index quality of ECONOMIC growth
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Underreporting of Energy Intake in Iraqi People Living in the UK According to Body Weight
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作者 Wassan A. Ahmed Waleed Al-Murrani Gail A. Rees 《Food and Nutrition Sciences》 2012年第3期317-321,共5页
Previous studies have shown that underreporting of energy intake is common when assessing dietary intake, particularly in the overweight and obese. The aim of this study was to obtain an estimate of energy and macronu... Previous studies have shown that underreporting of energy intake is common when assessing dietary intake, particularly in the overweight and obese. The aim of this study was to obtain an estimate of energy and macronutrient intake according to weight status and to investigate underreporting among Iraqi people living in the UK. Twenty eight adult volunteers (n = 16 males) were recruited. Dietary intake was estimated 3 times using the 24 hour dietary recall tech-nique. Portion size was estimated using household measures and the Photographic Atlas of Food Portion Sizes. Energy and macronutrients estimations were calculated, and weight and height were measured to calculate Body Mass Index (BMI). Energy intake was compared to estimated basal metabolic rate (BMR) and the Goldberg equation was used to assess underreporting. Of the overall sample, 57.1% (n = 16) and 21.4% (n = 6) subjects were overweight and obese, respectively. The mean energy intakes were low for males (1977 kcal/d) and females (1586 kcal/d). The percentage of under-reporters was high (57.1%) and this was higher in overweight and obese subjects (68.1%) compared to those of normal weight (4.5%). Overweight and obesity are common among well-educated Iraqi people. Underreporting of energy intake is common especially among overweight and obese Iraqi individuals. 展开更多
关键词 Energy OBESITY Body Mass Index Culture DIETARY Assessment
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10,000 years of climate control over carbon accumulation in an Iberian bog(southwestern Europe)
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作者 Xabier Pontevedra-Pombal Daniel Castro +7 位作者 Martín Souto Isabel Fraga William H. Blake Maarten Blaauw José A. López-Sáez Sebastián Pérez-Díaz Marcos Valcárcel Eduardo García-Rodeja 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第4期1521-1533,共13页
The northwest region of the Iberian Peninsula is home to a unique ecosystem of bogs,which are particularly sensitive to projected climate cha nge.In this context,the rate of carbon(C)accumulation in Chao de Veiga Mol.... The northwest region of the Iberian Peninsula is home to a unique ecosystem of bogs,which are particularly sensitive to projected climate cha nge.In this context,the rate of carbon(C)accumulation in Chao de Veiga Mol.an intact raised bog,was analysed.Changes in the accumulation rate over the past10 millennia were determined in a peat core of 847 cm in depth,with a high mean rate of peat growth(11 yr cm^-1,0.09 cm yr^-1).An age-depth model was generated from 22 14C dates and fallout radionuclides.Chronological,stratigraphical and physico-chemical data confirmed the existence of a single cycle of peat formation throughout the Holocene and the formation of ombrotrophic peat 9500 years ago.The total mean C content was 50.2%,and over 10 millennia 583 kg C m^-2 accumulated at a mean rate of 35.3 g C m^-2 yr^-1,with a long-term(apparent)rate of carbon accumulation in the catotelm of59.9 g C m^-2 yr^-1.These values are much higher than reported for other Iberian peatlands and are amongst the highest documented for peatlands in the northern hemisphere.The dynamics of C accumulation and other measured parameters reveals important variations throughout the Holocene.They could be associated with the main climatic events described in the northern hemisphere and are highly consistent with models established for northern latitudes.The Chao de Veiga Mol raised bog is unique and of great potential value for carrying out high resolution palaeoenvironmental studies,especially in relation to regional and Iocal modulations in southern Europe. 展开更多
关键词 PEATLAND GEOCHEMISTRY HOLOCENE Climate change Palaeoenvironmental reconstruction
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Do Water Matrix and Particulate Buffering Capacity Affect the Rate and Extent of P Release?
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作者 Jinbo Zhao Yingjun Xu +1 位作者 Li Xu Qian Li 《Journal of Water Resource and Protection》 2018年第1期59-72,共14页
The aim of this study was to investigate the release of inorganic and organic phosphorus species from particles in rivers and estuaries during resuspension events such as storm, wind and tidal induced turbulence. To a... The aim of this study was to investigate the release of inorganic and organic phosphorus species from particles in rivers and estuaries during resuspension events such as storm, wind and tidal induced turbulence. To achieve this aim, laboratory beaker experiments were designed with autoanalyzer 3 (AA3). The study first investigates phosphorus equilibration in ultra-pure water (UHP) water, biotic river water and abiotic river water under short term and long term conditions. Then, three typical organic and inorganic phosphorus compounds were selected (orthophosphate, phytic acid (PTA) and β-D-glucose-6-phosphate monosodium salt (G-6-P)) to simulate the effect of addition input to river and estuaries in the time period of 150 h. The results show that in a turbulent river, dissolved inorganic phosphorus (DIP) and dissolved organic phosphorus (DOP) will reach equilibrium between the particulate matter and the water column within 24 h. Additional input of DIP or DOP to the river, has different effects to the river nutrients balance. The buffering capacity of the suspended particulate matter (SPM) plays an important role and behavior difference to the inorganic and various organic phosphorus compounds. 展开更多
关键词 Nonpoint Source POLLUTION PHOSPHORUS RESUSPENSION PARTICULATE MATTER Laboratory Beacker Experiment RIVER
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