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Chinese Chemical Letters 2009年第10期20卷 1141-1144页

作者： Aye Aye Mar Ali Koohang Nathan D.Majewski Erika L.Szotek david A.Eiznhamer Michael t.Flavin Advanced Life Sciences Inc.1440 Davey RoadWoodridgeIL 60517 USA

28-Carboxymethoxy lupane tritepenoids 3 and 4 were synthesized by alkylation of betulin with the tHP protected 2- hydroxyethyl iodide followed by oxidation and reduction. Direct reaction of betulin （5） or betulone （10） with ethyl bromoacetate led to 28-O-acylation, instead of 28-O-alkylation. the targeted compounds 3 and 4 were not cytotoxic at the highest concentration tested （75 μmol/L）, suggesting that elongation of the chain length at the 28-position in both betulinic acid （1） and betulonic acid （2） was detrimental to the cytotoxicity. the acylation products 28-O-bromoacetates （Sa, 8b and 11） and 28-O-methoxyacetate 13 exhibited cytotoxicity against several cancer cell lines tested.

关键词： Betulinic acid Betulin Betulonic acid 28-O-Alkylation 28-O-Acylation Cytotoxicity

towards a fully data-driven prospectivity mapping methodology:A case study of the Southeastern Churchill Province,Québec and Labrador

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Artificial Intelligence in Geosciences 2021年第1期2卷 128-147页

作者： Steven E.Zhang Julie E.Bourdeau Glen t.Nwaila david Corrigan SmartMin Limited 39 Kiewiet StreetHelikon Park1759South Africa Geological Survey of Canada 601 Booth StreetOttawaOntarioK1A 0E8Canada School of Geosciences University of the Witwatersrand1 Jan Smuts AveJohannesburg2000South Africa Lynn Street GatineauQuebecJ9H 1B5Canada

Mineral exploration campaigns are financially *** state-of-the-art methods have been developed to mitigate the risk,including predictive modelling of mineral prospectivity using principal component analysis(PCA)and geographic information systems(GIS).the PCA and GIS approach is currently considered acceptable for generating mineral exploration ***,some of its limitations are the dependence on sample stoichiometry(e.g.,the existence of minerals),the necessity of log-ratio transformations when dealing with compositional data,and manual interpretation and use of principal components to enhance potential geochemical anomalies for prospectivity *** this study,we generalize the fundamental ideas behind the PCA and GIS approach by developing a new data-driven approach using *** showcase a new workflow capable of generating either intermediate evidence layers or final prospectivity maps that depict major regional geochemical anomalies using multi-element geochemical data from Southeastern Churchill Province(Quebec and Labrador),*** region is known for its REEs endowment and the data were gathered for prospectivity mapping.A comparison with the established multivariate hybrid data-and knowledge-based approach revealed that on a roughly comparable basis of the amount of manual effort,our new data-driven procedure can much more accurately identify geochemical anomalies in both univariate and multivariate *** results of our prospectivity mapping corroborate with the ground truth or known geological anomalies in the studied *** findings have potentially wider implications on exploration target generation,where project risks(financial,environmental,political,etc.)and geochemical anomalies must be quantified using robust and effective datadriven *** addition,our methodology is more replicable and objective,as manual geoscientific interpretation is not required during the detection of geochemical anomalies.

关键词： ML Mineral prospectivity mapping Principal component analysis Geochemical anomaly REEs

Cardiorespiratory and muscular fitness associations with older adolescent cognitive control

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Journal of Sport and Health Science 2021年第1期10卷 82-90,I0001页

作者： tatsuya t.Shigeta Angus A.Leahy Jordan J.Smith Narelle Eather david R.Lubans Charles H.Hillman Department of Psychology Northeastern UniversityBostonMA 02115USA Priority Research Centre for Physical Activity and Nutrition School of EducationUniversity of NewcastleCallaghanNSW 2308Australia Department of Physical therapy Movement&Rehabilitation SciencesNortheastern UniversityBostonMA 02131USA

Background:Participation in physical activity supports greater cardiorespiratory fitness(CRF),a correlate of cognitive ***,the relationship between muscular fitness(MF)and cognitive control is less *** present study investigated the differential relationship of CRF and MF with cognitive control in older ***:this cross-sectional study involved students(1517 years old,n=541,43%female)from 20 secondary schools who completed tests of inhibition(modified flanker task),working memory(n-back task),CRF(Progressive Aerobic Cardiovascular Endurance Run),and MF(standing long jump and push-up test).Multilevel analyses tested the association between CRF or MF and cognitive outcomes while accounting for the influence of the other fitness variable and relevant demographic ***:CRF predicted response accuracy during incongruent flanker trials,the condition requiring greater *** the working memory task,CRF predicted greater target accuracy and greater d’scores on the 1-back task,requiring lesser amounts of working *** the 2-back task,which requires greater amounts of working memory,CRF also predicted greater target and non-target accuracy and d’***,MF did not predict any cognitive outcomes after adjustment for ***:CRF was selectively related to better performance during task conditions that require greater amounts of inhibition and working *** finding suggests that CRF,but not MF,may benefit cognitive control in older *** selective influence of CRF on older adolescents’cognition highlights the value of aerobic physical activity.

关键词： Adolescence Cognition Physical activity Physical fitness

tandem cervical carotid stenting for stenosis with flow diversion embolisation for the treatment of intracranial aneurysms

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Stroke & Vascular Neurology 2019年第1期4卷 43-47页

作者： Jessica K Campos Li-Mei Lin Narlin B Beaty Matthew t Bender Bowen Jiang david A Zarrin Alexander L Coon Department of Neurosurgery Johns Hopkins University School of MedicineBaltimoreMarylandUSA Department of Neurosurgery University of CaliforniaIrvineOrangeCaliforniaUSA

Background An estimated 2%-3%of the population harbour an intracranial *** atherosclerotic cervical carotid disease is not *** management of these two entities remains a challenge within the *** presentation We report a single case of concomitant carotid stenosis and two ipsilateral unruptured intracranial aneurysms treated with a single-staged cervical carotid stenting and cerebral aneurysm embolisation with the Pipeline embolisation *** No consensus currently exists to guide endovascular treatment of intracranial aneurysms associated with asymptomatic ipsilateral ***,we present a case of asymptomatic moderate carotid stenosis with two ipsilateral intracranial aneurysms and suggest carotid artery stenting takes procedural priority over aneurysm embolisation in single-stage *** rationale for the sequence of neurointerventions is based on the tracking a robust distal access system beyond a stenotic proximal carotid lesion and stabilisation of the ulcerated plaque to avoid thromboembolic complications associated with plaque irritation during aneurysm *** cases and longer follow-up will be needed to further assess the efficacy of this technique.

关键词： aneurysm carotid stenosis

Ultrasmall Ag^＋-rich nanoclusters as highly efficient nanoreservoirs for bacterial killing

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Nano Research 2014年第3期7卷 301-307页

作者： Xun Yuan Magdiel I. Setyawati david t. Leong Jianping Xie Department of Chemical and Biomolecular Engineering National University of Singapore 4 Engineering Drive 4 117576 Singapore

Metallic silver （Ag） and its ability to combat infection have been known since ancient history. In the wake of nanotechnology advancement, silver＇s efficacy to fight broad spectrum bacterial infections is further improved in the form of Ag nanoparticles （NPs）. Recent studies have ascribed the broad spectrum antimicrobial properties of Ag NPs to dissociation of Ag＊ ions from the NPs, which may not be entirely applicable when the size of Ag NPs decreases to the sub-2 nm range [denoted Ag nanoclusters （NCs）]. In this paper we report that ultrasmall glutathione （GSH）-protected Ag^＋-rich NCs （Ag^＋-R NCs for short, with a predominance of Ag＋ species in the NCs） have much higher antimicrobial activities towards both gram-negative and gram-positive bacteria than the reference NC, GSH-Ag^＋-R NCs. they have the same size and surface ligand, but with different oxidation states of the core silver. this interesting finding suggests that the undissociated Ag^＋-R NCs armed with abundant Ag^＋ ions on the surface are highly active in bacterial killing, which was not observed in the system of their larger counterpart, Ag NPs.

关键词： noble metal nanoclusters silver antimicrobial agent biomedicine bacteria

Stathmin as a surrogate marker of phosphatidylinositol-3-kinase pathway activity:towards precision medicine in HPV-negative head&neck squamous cell carcinoma

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Genes & Diseases 2022年第3期9卷 820-825页

作者： Andrew t.turk Dario Garcia-Carracedok david t.Kent Elizabeth Philipone Juana Maria Garcia-Pedrero Salvatore M.Caruana Lanny G.Close Gloria H.Su Department of Pathology and Cell Biology and Columbia UniversityNew YorkNY 10032USA Department of Otolaryngology Columbia UniversityNew YorkNY 10032USA Department of Otolaryngology Vanderbilt UniversityNashvilleTN 37232USA Department of Otolaryngology Hospital Universitario Central de Asturias and Instituto Universitario de Oncologia Del Principado de AsturiasOviedo 33006Spain

In order to assess Stathmin as an immunohistochemical(IHC)indicator of phosphatidylinositol 3-kinase(PI3K)pathway activity in HPV-negative head&neck squamous cell carcinoma(HNSCC),we compared Stathmin IHC to expression of other pathway *** also evaluated the relationship between Stathmin IHC and the mutational status of four key pathway ***,we ascertained whether Stathmin IHC correlates with tumor grade or primary *** exists between high Stathmin expression and high pAKt1 expression,indicating a role for Stathmin IHC as a marker of pathway *** analysis did not show correlation between Stathmin IHC and mutation of the four genes *** also observed an association between high Stathmin expression and oropharyngeal primary *** results suggest utility of Stathmin IHC as an indicator of PI3K pathway activity,and thereby demonstrate potential relevance of Stathmin IHC in the context,of HNSCC.

关键词： Cancer Head&neck squamous cell carcinoma Pathology Stathmin

Recent advances in targeting the autotaxin-lysophosphatidate-lipid phosphate phosphatase axis in vivo

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the Journal of Biomedical Research 2016年第4期30卷 272-284页

作者： Matthew G.K. Benesch Xiaoyun tang Ganesh Venkatraman Raie t. Bekele david N. Brindley Signal transduction Research Group Department of Biochemistry University of Alberta T6G 2S2 Canada.

Extracellular lysophosphatidate （LPA） is a potent bioactive lipid that signals through six G-protein-coupled receptors. this signaling is required for embryogenesis, tissue repair and remodeling processes. LPA is produced from circulating lysophosphatidylcholine by autotaxin （AtX）, and is degraded outside cells by a family of three enzymes called the lipid phosphate phosphatases （LPPs）. In many pathological conditions, particularly in cancers, LPA concentrations are increased due to high AtX expression and low LPP activity. In cancers, LPA signaling drives tumor growth, angiogenesis, metastasis, resistance to chemotherapy and decreased efficacy of radiotherapy. Hence, targeting the AtX-LPA-LPP axis is an attractive strategy for introducing novel adjuvant therapeutic options. In this review, we will summarize current progress in targeting the AtX-LPA-LPP axis with inhibitors of autotaxin activity, LPA receptor antagonists, LPA monoclonal antibodies, and increasing low LPP expression. Some of these agents are already in clinical trials and have applications beyond cancer, including chronic inflammatory diseases.

关键词： cancer chronic inflammation cytokines monoclonal antibodies wound repair

Percutaneous coronary interventions in the elderly:a 10-year experience in Northern New England

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Journal of Geriatric Cardiology 2005年第1期2卷 17-22页

作者： david J.Malenka James t.DeVries Samuel J.Shubrooks for the Northern New England Cardiovascular Disease Study Group Section of Cardiology Dartmouth-Hitchcock Medical Center LebanonNH Center for the Evaluative Clinical Sciences Dartmouth Medical SchoolHanoverNHUSA for the Northern New England Cardiovascular Disease Study Group Section of Cardiology Dartmouth-Hitchcock Medical Center LebanonNHUSA for the Northern New England Cardiovascular Disease Study Group Division of Cardiology Beth Israel-Deaconess Medical Center BostonMAUSA Jr

Background there is a paucity of information available for clinical decision making applying to the elderly patient population. therefore, data of percutaneous coronary interventions (PCI) including demographic information on the elderly patients, procedural practices, and outcomes are needed. Objectives and Methods From consecutive PCIs of participating institutions, demographics data, clinical, angiographic success and adverse clinical outcomes were collected. Standard statistical methods were used to compare crude differences in patient and procedural characteristics across age groups. Results At baseline, the prevalence of comorbid conditions ( renal failure and heart failure) increased with age. Unstable angina or a non-St elevation MI were the most common indications for PCI across all age groups. Fewer patients ≥ 80 years old were undergoing primary PCI and older patients were somewhat less likely to receive a Ⅱb/Ⅲa receptor blocker. Slightly more patients ≥ 80 years old underwent a 2-vessel PCI ( consistent with them having more multivessel disease) and these patients were more likely to have an intervention on a type C lesion. Compared to patients ＜ 50 years old, those aged ≥ 70 years old had a significantly increased risk of death, MI, stroke, or vascular complications at the access site. Conclusions this study suggests increasing age is associated with increasing risk for an adverse outcome following PCI. this is in part attributable to case-mix but likely, also related to the changing physiology of aging. Despite the increased risk of the procedure, the clinical success rate for PCI is quite high and makes it a reasonable alternative for the treatment of CAD in the elderly.

关键词： coronary artery disease elderly percutaneous coronary intervention

Applicability of differential fluorescein diacetate and propidium iodide fluorescence staining for monitoring algal growth and viability

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Waste Disposal and Sustainable Energy 2019年第3期1卷 199-206页

作者： Swati Yewalkar tong Wu david Kuan Heli Wang Di Li Andy Johnson Dusko Posarac Sheldon Duff Xiaotao t.Bi Department of Chemical and Biological Engineering The University of British ColumbiaVancouverCanada School of Water Resource and Environment China University of GeosciencesBeijingChina Biomedical Research Center The University of British ColumbiaVancouverCanada

Microalgae can be cultivated for producing high-valued products through the production of enzymes to offset the cost of CO_(2) sequestration,providing financial *** viability of algae in the photobioreactor needs to be monitored to ensure biologically active live *** this study,we explored a simple fluorometry method for differentiation of live and dead algal cells in photobioreactors by fluorescein diacetate(FDA)and propidium iodide(PI)fluorescence *** stains fluorescent green to the living cells while PI stains the dead cells,allowing the discrimination of live and dead *** method was evaluated using two green algae and two strains of cyanobacteria grown in shake flasks and a continuously stirred *** method was found applicable for Chlorella pyrenoidosa and Synechococcus 7002 but was not applicable for the cultures of Scenedesmus dimorphus and Synechococcus elongatus *** conclude that FDA is a good stain for monitoring live algal cells in photobioreactors but its applicability to individual species of algae must be evaluated.

关键词： Fluorescein diacetate(FDA) Propidium iodide(PI) Live and dead algae Differential staining Continuous photobioreactor

Dual-shell silicate and alumina coating for long lasting and high capacity lithium ion batteries

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Journal of Energy Chemistry 2022年第5期31卷 314-323页

作者： Marcos Lucero tucker M.Holstun Yudong Yao Ryan Faase Maoyu Wang Alpha t.N’Diaye david P.Cann Joe Baio Junjing Deng Zhenxing Feng School of Chemical Biologicaland Environmental EngineeringOregon State UniversityCorvallisOR 97331United States Advanced Photon Source Argonne National LaboratoryArgonneIllinois 60439United States Advanced Light Source Lawrence Berkeley National LaboratoryBerkeleyCalifornia 94720United States Materials Science School of MechanicalIndustrialand Manufacturing EngineeringOregon State UniversityCorvallisOR 97331United States

Here we demonstrate a theory-driven, novel dual-shell coating system of Li_(2)SrSiO_(4) and Al_(2)O_(3), achieved via a facile and scalable sol-gel technique on LiCoO_(2) electrode particles. the optimal thickness of each coating can lead to increased specific capacity(~185 m Ah/g at 0.5 C-rate) at a cut-off potential of 4.5 V, and greater cycling stability at very high C rates(up to 10 C) in half-cells with lithium metal. the mechanism of this superior performance was investigated using a combination of X-ray and electron characterization methods. It shows that the results of this investigation can inform future studies to identify still better dual-shell coating schemes, achieved by such industrially feasible techniques, for application on similar, nickel-rich cathode materials.

关键词： Lithium cobalt oxide Surface coating Sol-gel Silicate Alumina X-ray absorption spectroscopy