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沉积物选择性起动机理及其在砾石沉积临界值分析中的应用

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海洋与湖沼 1992年第1期23卷 30-38页

作者：李振林秦蕴珊 paul d.komar 中国科学院海洋研究所青岛266071 美国俄勒冈州立大学海洋学院

混合粒径条件下沉积物的起动机理不同于均匀粒径条件下沉积物的起动机理。混合粒径条件下沉积物的起动,可由沉积物转动角Φ随相对粒径及颗粒形状而变化的依从关系进行解释。通过对砾石沉积物因木同粒径、形状而发生选择性起动的动力过... 详细信息

混合粒径条件下沉积物的起动机理不同于均匀粒径条件下沉积物的起动机理。混合粒径条件下沉积物的起动,可由沉积物转动角Φ随相对粒径及颗粒形状而变化的依从关系进行解释。通过对砾石沉积物因木同粒径、形状而发生选择性起动的动力过程的分析,得出了砾石沉积物转动角选择性起动的理论模式,采用该模式来定量计算潮汐流和河流中砾石沉积物选择性起动的临界值,计算结果和测量结果吻合,从而证实了该模式的可靠性。

关键词：沉积物选择性起动运动机理砾石沉积临界转动角

Spectral analysis in ultraweak emissions of chemi-and electrochemiluminescence systems

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Journal of Rare Earths 2009年第4期27卷 593-597页

作者： K.Staninski M.Kaczmarek S.Lis d.komar A.Szyczewski Faculty of Chemistry Adam Mickiewicz University Faculty of Physics Adam Mickiewicz University

Investigation of ultraweak emissions in the processes of chemiluminescence, CL, and electrochemiluminesce, ECL, requires special techniques of their recording and spectral analysis. From among the hitherto proposed methods of detection of the emission spectra of these processes, that of the cut-off filter was most sensitive. The usefulness of this method in interpretation of the CL and ECL systems of the quantum yields in the range 1×10^-9-1×10^-11 containing ions and complexes of Eu（Ⅲ）, Tb（Ⅲ） and dy0Id was shown. Exceptional character of the emission bands of lanthanide ions, being a result of the f-f electron transitions and in particular their low FWHM, permitted the appli- cation of the cut-off filter method to their analysis. The results obtained for CL and ECL on the basis of analysis of ultraweak emission proved to be successful in analytical applications. The systems containing Eu（Ⅲ） ions hydrated or complexed with organic ligands enabled inferring changes in the coordination sphere of the ions.

关键词： chemiluminescence electrochemiluminescence cut-off fdter method lanthanide rare earths

Evidence supporting the relationship between maternal asthma and risk for autism spectrum disorders

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Neural Regeneration Research 2025年第4期20卷 1101-1102页

作者： Hadley Osman paul Ashwood department of Medical Microbiology and Immunology and the M.I.N.D.InstituteUniversity of California at DavisSacramentoCAUSA

during pregnancy,maternal immune activation(MIA),due to infection,chronic inflammatory disorders,or toxic exposures,can result in lasting health impacts on the developing *** has been associated with an increased risk of neurodevelopmental disorders,such as autism spectrum disorder(ASd)in the *** is characterized by increased repetitive and stereotyped behaviors and decreased *** of 2020,1 in 36 children are diagnosed with ASd by the age of 8 years,with ASd rates continuing to increase in prevalence in USA(Tamayo et al.,2023).Post-mortem brain studies,biomarker and transcriptomic studies,and epidemiology studies have provided compelling evidence of immune dysregulation in the circulation and brain of individuals diagnosed with ***,the etiology of ASd is largely unknown,however,genetic components and environmental factors can contribute to increased *** allergic asthma(MAA),a form of MIA,has been identified as a potential risk factor for developing neurodevelopmental disorders(Patel et al.,2020).Asthma is a chronic inflammatory condition driven by a T-helper type(TH)2 immune response.

关键词： disorders epidemiology fetus

Emerging insights into the function of very long chain fatty acids at cerebellar synapses

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Neural Regeneration Research 2025年第6期20卷 1709-1710页

作者： Martin-paul Agbaga Mohiuddin Ahmad department of Cell Biology and Ophthalmology University of Oklahoma Health Sciences Centerand Dean McGee Eye InstituteOklahoma CityOKUSA

Very long chain-saturated and-polyunsaturated fatty acids(VLC-SFA and VLC-PUFA, respectively) are a functionally important class of fatty acids containing 28 carbons or more in their acyl chain. They are synthesized by the elongation of very long fatty acids-4(ELOVL4) enzyme, expressed mainly in the brain, retina, skin, testes, and meibomian gland, where these fatty acids are found(Agbaga et al., 2008). Further, these organs exhibit tissuespecific VLC-PUFA and VLC-SFA biosynthesis and incorporation into complex lipids for specific functions. In the brain, skin, and Meibomian glands, the ELOVL4 mainly makes VLC-SFA, which are incorporated into complex sphingolipids. In the retina, the ELOVL4 makes VLC-PUFA that are incorporated into phosphatidylcholine, that are critical for visual function, while in testes and sperm, the VLC-PUFA are incorporated into sphingolipids that are critical for fertility(Yeboah et al., 2021).

关键词： functions function insight

distinct expression profiles of transcriptional coactivators for thyroid hormone receptors during Xenopus laevis metamorphosis

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Cell Research 2003年第6期13卷 459-464页

作者： BINdU d paul National Institutes of Health Laboratory of Gene Regulation and development National Institute of Child Health and Human development Bldg. USA.

The biological effects of thyroid hormone (T3) are mediated by the thyroid hormone receptor (TR). Amphibian metamorphosis is one of the most dramatic processes that are dependent on T3. T3 regulates a series of orchestrated developmental changes, which ultimately result in the conversion of an aquatic herbivorous tadpole to a terrestrial carnivorous frog. T3 is presumed to bind to TRs, which in turn recruit coactivators, leading to gene activation. The best-studied coactivators belong to the p160 or SRC family. Members of this family include SRC1/ NCoA-1, SRC2/TIF2/GRIP1, and SRC3/pCIP/ACTR/AIB-l/RAC-3/TRAM-1. These SRCs interact directly with liganded TR and function as adapter molecules to recruit other coactivators such as p300/CBP. Here, we studied the expression patterns of these coactivators during various stages of development. Amongst the coactivators cloned in Xenopus laevis, SRC3 was found to be dramatically upregulated during natural and T3-induced metamorphosis, and SRC2 and p300 are express

关键词： transcription coactivators thyroid hormone receptor Xenopus laevis metamorphosis histone acetylation.

Increased Light, Moderate, and Severe Clear-Air Turbulence in Response to Climate Change

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Advances in Atmospheric Sciences 2017年第5期34卷 576-586页

作者： paul d. WILLIAMS department of Meteorology University of Reading Reading RG6 6BB United Kingdom

Anthropogenic climate change is expected to strengthen the vertical wind shears at aircraft cruising altitudes within the atmospheric jet streams. Such a strengthening would increase the prevalence of the shear instabilities that generate clear-air turbulence. Climate modelling studies have indicated that the amount of moderate-or-greater clear-air turbulence on transatlantic flight routes in winter will increase significantly in future as the climate changes. However,the individual responses of light,moderate,and severe clear-air turbulence have not previously been studied,despite their importance for aircraft operations. Here,we use climate model simulations to analyse the transatlantic wintertime clear-air turbulence response to climate change in five aviation-relevant turbulence strength categories. We find that the probability distributions for an ensemble of 21 clear-air turbulence diagnostics generally gain probability in their right-hand tails when the atmospheric carbon dioxide concentration is doubled. By converting the diagnostics into eddy dissipation rates,we find that the ensembleaverage airspace volume containing light clear-air turbulence increases by 59%(with an intra-ensemble range of 43%–68%),light-to-moderate by 75%(39%–96%),moderate by 94%(37%–118%),moderate-to-severe by 127%(30%–170%),and severe by 149%(36%–188%). These results suggest that the prevalence of transatlantic wintertime clear-air turbulence will increase significantly in all aviation-relevant strength categories as the climate changes.

关键词： turbulence climate change aviation jet stream

High-resolution geological maps of central London, UK： Comparisons with the London Underground

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Geoscience Frontiers 2016年第2期7卷 273-286页

作者： Jonathan d. paul department of Earth Sciences Bullard Laboratories University of Cambridge Madingley Rise Cambridge CB3 0EZ UK

This study presents new thickness maps of post-Cretaceous sedimentary strata beneath central London. 〉1100 borehole records were analysed. London Clay is thickest in the west; thicker deposits extend as a narrow finger along the axis of the London Basin. More minor variations are probably governed by periglacial erosion and faulting. A shallow anticline in the Chalk in north-central London has resulted in a pronounced thinning of succeeding strata. These results are compared to the position of London Underground railway tunnels. Although tunnels have been bored through the upper levels of London Clay where thick, some tunnels and stations are positioned within the underlying, more lithologically variable, Lower London Tertiary deposits. Although less complex than other geological models of the London Basin, this technique is more objective and uses a higher density of borehole data. The high resolution of the resulting maps emphasises the power of modelling an expansive dataset in a rigorous but simnle fashion.

关键词： London London Underground London Clay Lambeth Group Chalk Tunnelling Boreholes

Chronic kidney disease and the skeleton

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Bone Research 2014年第4期2卷 205-217页

作者： paul d Miller Colorado Center for Bone Research LakewoodCO.USA

Fractures across the stages of chronic kidney disease （CKd） could be due to osteoporosis, some form of renal osteodystrophy defined by specific quantitative histomorphometry or chronic kidney disease-mineral and bone disorder （CKd-MBd）. CKd-MBd is a systemic disease that links disorders of mineral and bone metabolism due to CKd to either one or all of the following： abnormalities of calcium, phosphorus, parathyroid hormone or vitamin d metabolism; abnormalities in bone turnover, mineralization, volume, linear growth or strength; or vascular or other soft-tissue calcification. Osteoporosis, as defined by the National Institutes of Health, may coexist with renal osteodystrophy or CKd-MBd. differentiation among these disorders is required to manage correctly the correct disorder to reduce the risk of fractures. While the World Health Organization （WHO） bone mineral density （BMd） criteria for osteoporosis can be used in patients with stages 1-3 CKd, the disorders of bone turnover become so aberrant by stages 4 and 5 CKd that neither the WHO criteria nor the occurrence of a fragility fracture can be used for the diagnosis of osteoporosis. The diagnosis of osteoporosis in stages 4 and 5 CKd is one of the exclusion--excluding either renal osteodystrophy or CKd- MBd as the cause of low BMd or fragility fractures. differentiations among the disorders of renal osteodystrophy, CKd-MBd or osteoporosis are dependent on the measurement of specific biochemical markers, including serum parathyroid hormone （PTH） and/or quantitative bone histomorphometry. Management of fractures in stages 1-3 CKd does not differ in persons with or without CKd with osteoporosis assuming that there is no evidence for CKd-MBd, clinically suspected by elevated PTH, hyperphosphatemia or fibroblast growth factor 23 due to CKd. Treatment of fractures in persons with osteoporosis and stages 4 and 5 CKd is not evidence-based, with the exception of post-hoc analysis suggesting efficacy and safety of specific o

关键词： CKd GFR PTH MBd

Enhanced Trust Based Access Control for Multi-Cloud Environment

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Computers, Materials & Continua 2021年第12期69卷 3079-3093页

作者： N.R.Rejin paul d.paul Raj Technology PuduvoyalGummidipoondi601206India R M d Engineering College KavaraipettaiGummidipoondi601206India

Security is an essential part of the cloud *** ensuring the security of the data being communicated to and from the cloud server,a significant parameter called trust was ***-based security played a vital role in ensuring that the communication between cloud users and service providers remained unadulterated and *** most cloud-based data distribution environments,emphasis is placed on accepting trusted client users’requests,but the cloud servers’integrity is seldom *** paper designs a trust-based access control model based on user and server characteristics in a multi-cloud environment to address this *** proposed methodology consists of data encryption using Cyclic Shift Transposition Algorithm and trust-based access control *** this trust-based access control mechanism framework,trust values are assigned to cloud users using direct trust *** direct trust degree is estimated based on the following metrics:success and failure rate of interactions,service satisfaction index,and dishonesty *** addition to this,trust values are assigned to cloud servers based on the metrics:server load,service rejection rate,and service access *** role-Based Access control policy of each user is modified based on his trust *** the server fails to meet the minimum trust level,then another suitable server will be *** proposed system is found to outperform other existing systems in a multi-cloud environment.

关键词： Cloud computing trust access control cloud service provider cloud data user CSTA