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Modified Piyavskii’s Global One-Dimensional Optimization of a Differentiable Function

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Applied Mathematics 2012年第10期3卷 1306-1320页

作者： Rachid Ellaia Mohamed Zeriab es-Sadek Hasnaa Kasbioui Mohammadia School of Engineering Mohammed V University Rabat Morocco

Piyavskii’s algorithm maximizes a univariate function satisfying a Lipschitz condition. We propose a modified Piyavskii’s sequential algorithm which maximizes a univariate differentiable function f by iteratively constructing an upper bounding piece-wise concave function Φ of f and evaluating f at a point where Φ reaches its maximum. We compare the numbers of iterations needed by the modified Piyavskii’s algorithm (nC) to obtain a bounding piece-wise concave function Φ whose maximum is within ε of the globally optimal value foptwith that required by the reference sequential algorithm (nref). The main result is that nC≤ 2nref + 1 and this bound is sharp. We also show that the number of iterations needed by modified Piyavskii’s algorithm to obtain a globally ε-optimal value together with a corresponding point (nb) satisfies nbnref + 1 Lower and upper bounds for nref are obtained as functions of f(x) , ε, M1 and M0 where M0 is a constant defined by M0 = supx∈[a,b] - f’’(x) and M1 ≥ M0 is an evaluation of M0.

关键词： Global Optimization Piyavskii’s Algorithm

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烷基9-氮硝基喜树碱酯类的构效关系

Acta Pharmacologica Sinica 2003年第2期24卷 109-119页

作者： Panayotis PANTAZIS John MENDOZA janet EARLY Anthony KOZIELSKI Nick harris beppino GIOVANELLA The Stehlin Foundation for Cancer Research at St. Joseph Hospital 1918 Chenevert Houston Texas 77003 USA The Stehlin Foundation for Cancer Research at St. Joseph Hospital 1918 Chenevert Houston Texas 77003 USA The Stehlin Foundation for Cancer Research at St. Joseph Hospital 1918 Chenevert Houston Texas 77003 USA The Stehlin Foundation for Cancer Research at St. Joseph Hospital 1918 Chenevert Houston Texas 77003 USA The Stehlin Foundation for Cancer Research at St. Joseph Hospital 1918 Chenevert Houston Texas 77003 USA The Stehlin Foundation for Cancer Research at St. Joseph Hospital 1918 Chenevert Houston Texas 77003 USA

AIM: To study the structure-activity relationship of alkyl 9-nitrocamptothecin esters. METHODS: Two alkyl 9-nitrocamptothecin (9NC) esters 5g and 5h were prepared by esterification reactions of 9NC with valeric anhydride and heptanoic anhydride, respectively. Eight 9NC esters 5a-5h were tested for cytotoxicity against human leukemia cell lines HL-60 and U-937. Flow cytometry analysis was used to identify the cell cycle phase targeted by the esters and quantify the extent of ester-induced cell death (apoptosis). ResULTS: esters 5b and 5c demonstrated great abilities to inhibit growth of the leukemia cells followed by induction of apoptosis; esters 5a, 5e, and 5g induced slight perturbations in the cell cycle at high concentrations; and esters 5d, 5f, and 5h were completely inactive against the cell lines tested. Thus these esters showed the cell anti-proliferative activity in an order of 5b≈5c>5a≈5e≈5g>5d≈5f≈5h. esters 5b, 5c, and 5e were tested in vivo against various human carcinomas in nude mice grown as xenografts. Only 5b and 5c showed a significant antitumor activity. Particularly, ester 5b demonstrated an antitumor activity against a broad spectrum of human carcinomas including breast, lung, colon, pancreas, stomach, ovarian, and melanoma, etc. CONCLUSION: These esters act like prodrugs of their parental 9-nitrocamptothecin. High drug doses need to be administered to animals in order to inhibit growth, and induce regression, of human tumor xenografts in nude mice. These compounds may be developed into potent anticancer drugs due to their low toxicity.

关键词：喜树碱酯类药物前体抗肿瘤药毒性构效关系

Three challenges for future research on cochlear implants

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2017年第4期3卷 240-254页

作者： David b.Pisoni William G.Kronenberger Michael S.harris Aaron C.Moberly Department of Otolaryngology-Head and Neck Surgery DeVault Otologic Research LaboratoryIndiana University School of Medicine Indianapolis IN 46205 USA Department of Otolaryngology and Communication Sciences Medical College of WisconsinMilwaukee WI 53211 USA Department of Otolaryngology-Head and Neck Surgery The Ohio State University Wexner Medical Center Columbus OH 43212 USA

Cochlear implants (CIs) often work very well for many children and adults with profound sensorineural (SNHL) hearing ***,while many CI patients display substantial benefits in recognizing speech and understanding spoken language forlowing cochlear implantation,a large number of patients achieve poor *** and explaining the reasons for poor outcomes forlowing implantation is a very challenging research problem that has received little attention despite the pressing clinical *** this paper,we discuss three challenges for future research on ***,we consider the issue of individual differences and variability in outcomes following *** the present time,we still do not have a complete and satisfactory account of the causal underlying factors that are responsible for the enormous individual differences and variability in ***,we discuss issues related to the lack of preimplant predictors of *** little prospective research has been carried out on the development of preimplant predictors that can be used to reliably identify CI candidates who may be at high risk for a poor outcome forlowing *** than conventional demographics and hearing history,there are no prognostic tools available to predict speech recognition outcomes after ***,we discuss the third challenge-what to do with a CI-user who has a poor *** suggest that new research efforts need to be devoted to studying this neglected clinical population in greater depth to find out why they are doing poorly with their Cl and what novel interventions and treatments can be developed to improve their speech recognition *** these three challenges as objectives for future research on Cls,we suggest that the field needs to adopt a new narrative grounded in theory and methods from Cognitive Hearing Science and information processing *** knowing which specific biological and neurocognitive

关键词： Hearing loss Cochlear implants Outcomes following implantation

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Effect of dexamethasone injection into Zusanli(ST 36) acupoint on ovalbumin-induced allergic rhinitis

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Journal of Traditional Chinese Medicine 2019年第3期39卷 307-314页

作者： Na-Ra Han Seung-Jun Han Phil-Dong Moon Sungwei Hong Hyeongjin Kim Yanhua Li Hyung-Min Kim Hyun-ja Jeong Department of Pharmacology College of Korean Medicine Kyung Hee University Seoul 02447 Republic of Korea Department of Korean Medicine Graduate School of Wonkwang University Iksan 54538 Republic of Korea Department of Pharmacology Graduate School Kyung Hee University Seoul 02447Republic of Korea Department of Clinical Korean Medicine Graduate School Kyung Hee University Seoul 02447 Republic of Korea Department of Food Science & Technology and Research Institute for basic Science Hoseo UniversityChungnam 31499 Republic of Korea

ObJECTIVE:To investigate the effects of acupunc ture with dexamethasone(***)on allergic rhini tis(AR)by injecting dexamethasone into the Zusan li(ST 36)***:Thirty 6-week-old female bALb/c mice were sensitized on days 1,5,and 14 by intraperitoneal injection of 100 pg of ovalbumin(OVA).The mice were then randomly divided into six groups(n =5 in each group).Five groups were sensitized intranasally with 2μL of 1.5 mg of OVA for 10 consecutive days,while one group was sensitized intranasally with PbS in a similar manner as a negative control *** hour before each administration of intranasal OVA,two groups were orally administered either a control vehicle(distilled water;AR control group)or 200 pg/kg Dex(*** group),while three groups received *** at Zusanli(ST36)with Dex concentrations of 2,20,and 200μg/kg for each group,*** symptoms were evaluated by measuring the rubbing score,which comprised the number of nose,ear,and eye rubs that occurred in the initial 10 min after OVA intranasal provocation on the 10 th *** isolated spleen,serum,and nasal mucosal tissue after measuring the rubbing *** weight was measured using an electronic *** levels of IgE,thymic stromal lymphopoietin,tumor necrosis factor-a,intercellular adhesion molecule-1,and macrophage-inflammatory protein-2 in serum or nasal mucosal tissue were measured using enzyme-linked immunosorbent *** serum histamine levels of OVA-sensitized AR mice were measured using O-phthaldialdehyde *** blot analysis was performed on nasal mucosal tissue ***:*** significantly reduced the rubbing score,spleen weight,serum IgE,and serum histamine in OVA-sensitized *** significantly decreased the serum levels of inflammatory cytokines(thymic stromal lymphopoietin and tumor necrosis factor-a)in OVA-sensitized *** significantly reduced the nasal mucosal levels of inflammatory markers(intercellular adhesion molecule-l

关键词： Dexamethasone Point ST36 (Zusanli) Pharmaceutical research Acupuncture Rhinitis,allergic Ovalbumin Thymic stromal lymphopoietin

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男性C反应蛋白、纤维蛋白原和心肺适应性与高血压发生风险的相关性

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中华高血压杂志 2015年第9期23卷 887-889页

作者： jae SY Kurl S Laukkanen ja Lee CD Choi YH Fernhall b Franklin bA 机构不详

在正常血压和高血压高危人群中,较高的心肺适应性（cardiorespiratory fitness）可预防高血压[1-2]。但高心肺适应性能否降低炎症水平升高的受试者发生高血压的风险,尚不清楚。本研究旨在探讨男性中,独立于肥胖,炎症与高血压发生的相关... 详细信息

在正常血压和高血压高危人群中,较高的心肺适应性（cardiorespiratory fitness）可预防高血压[1-2]。但高心肺适应性能否降低炎症水平升高的受试者发生高血压的风险,尚不清楚。本研究旨在探讨男性中,独立于肥胖,炎症与高血压发生的相关性;心肺适应性、炎症与高血压发生的联合相关性。研究者假设炎症与高血压发生相关,但高心肺适应性可降低这种相关性。

关键词：防高血压发生风险相关性适应性 C反应蛋白纤维蛋白原心肺男性

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轧制铀棒择优取向的定量测量

钢铁研究情报 1978年第Z1期 64-71页

作者： G.b.harris 黄清珠

用盖革计数管X光衍射方法定量地测定了热轧及在α相区内冷轧铀棒的择优取向。测量结果表明,轻微压下的热轧使010面强烈地取垂直于轧向的方向,而110面微弱地取此方向。而进一步热轧使110面强烈地取垂直于轧向的方向,而010面微弱地取此方... 详细信息

用盖革计数管X光衍射方法定量地测定了热轧及在α相区内冷轧铀棒的择优取向。测量结果表明,轻微压下的热轧使010面强烈地取垂直于轧向的方向,而110面微弱地取此方向。而进一步热轧使110面强烈地取垂直于轧向的方向,而010面微弱地取此方向。轻微冷轧使010面强烈地取垂直于轧向的方向。而130面轻微地取此方向。

关键词：择优取向铀棒光衍射方法织构盖革计数管辐射计数管晶面法线定量测量

HOST SPECIFICITY IN WEED bIOCONTROL

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HOST SPECIFICITY IN WEED BIOCONTROL

Nonalcoholic fatty liver disease in asymptomatic brazilian adolescents

The 18th Asian-Pacific Weed Science Society Conference

作者： P.harris Agriculture＆Agri-Food Canada Lethbridge Research CentrePO Box 3000LethbridgeABCanadaT1J 4B1

＜正＞Host range determination is essential to exclude release of weed biocontrol agents harmful to desirable *** this is largely based on host range surveys in the native region and lack of larval development in no-choice *** 10%of the agents established in Canada have no-choice host ranges narrower than the field range, 20%are the same and 70%are *** 90%of those in the last category developed in no-choice test on North American plants closely related to the host;but only 4%have attacked them in the *** native flora is a sensitive issue so there is an urgent need to identify which are actually at risk.A combination of the native field host range and no-choice test limits risk to a plant *** releasing agents that develop on critical plants in the taxon eliminates most biocontrol *** strategies less destructive to weed biocontrol are suggested for achieving the same end.1) Extend the host range surveys to determine the candidates physical and biological needs.2) Restrict release to candidate agents not accepting the critical plants in native-region field tests.3) Determine risk from the relative suitability of critical plants to the host.4) Reject candidates if host finding or acceptance of critical plants is *** strategies are not mutually exclusive.

关键词： Host range no-choice tests supplementary tests

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World Journal of Gastroenterology 2009年第4期15卷 473-477页

作者： Raquel Rocha Helma Pinchemel Cotrim Almir Galvo Vieira bitencourt Daniel batista Valente barbosa Adméia Souza Santos Alessandro de Moura Almeida bruno Cunha Isabel Guimares Postgraduate Course in Medicine and Health Federal University of BahiaSchool of Medicine Federal University of bahia School of Medicine NASH Project University Hospital Professor Edgard SantosFederal University of Bahia

AIM： To evaluate the prevalence and clinical characteristics of Nonalcoholic fatty liver disease （NAFLD） among asymptomatic brazilian adolescents. METHODS： Transversal observational study included asymptomatic adolescents with central obesity from private and public schools in Salvador-bahia, northeastern brazil. The children answered a questionnaire that in- cluded age, gender, race, and medical history, and were submitted to a complete physical exam and abdominal ultrasound. biochemical exams included： ALT, AST, GGT, C reactive protein （CRP）, fasting glucose, insulin, cholesterol and triglycerides. Criteria for NAFLD included： the presence of steatosis in ultrasound and/or high level of ALT, negative or occasional historic of intake of alcohol （4 140 g/wk）, negative investigation for hepatitis A, b, C, auto-immune hepatitis, Wilson disease and ***： From October, 2005 to October, 2006, the study included 1801 subjects between 11 and 18 years of age and a mean age of 13.7± 2.0 years. One hun- dred ninety-nine had central obesity. The prevalence of NAFLD was 2.3%, most of whom were male and white. Insulin resistance （IR） was observed in 22.9% of them and had positive correlations with ALT and GGT （P 〈 0.05）. Elevated CRP was observed in 6.9% of the cases; however, it was not associated with WC, IR or liver enzymes. CONCLUSION： The prevalence of NAFLD in brazilian adolescents was low. The ethnicity may have influence this frequency in the population studied, which had a large proportion of African descendents.

关键词： Nonalcoholic fatty liver disease Insulinresistance Central obesity Ethnicity Adolescents

Endovascular treatment in anterior circulation stroke beyond 6.5 hours after onset or time last seen well:results from the MR CLEAN Registry

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Stroke & Vascular Neurology 2021年第4期6卷 572-580,I0037-I0048页

作者： Luuk Dekker esmee Venema F Anne V Pirson Charles b L M Majoie bart J Emmer Ivo G H jansen Maxim J H L Mulder Robin Lemmens Robert-jan b Goldhoorn Marieke J H Wermer Jelis boiten Geert J LycklamaàNijeholt Yvo b W E M Roos Adriaan C G M van es Hester F Lingsma Diederik W J Dippel Wim H van Zwam Robert J van Oostenbrugge Ido R van den Wijngaard on behalf of the MR CLEAN Registry investigators Neurology Leiden University Medical CentreLeidenThe Netherlands Neurology Erasmus MCRotterdamThe Netherlands Public Health Erasmus MCRotterdamThe Netherlands Neurology Maastricht University Medical Centre+MaastrichtThe Netherlands Radiology and Nuclear Medicine Amsterdam University Medical CentreLocation AMCAmsterdamThe Netherlands Neurology University Hospitals LeuvenLeuvenBelgium Neurosciences Experimental Neurology and Leuven Brain InstituteUniversity of LeuvenLeuvenBelgium VIb Center for Brain&Disease ResearchLaboratory of NeurobiologyLeuvenBelgium Neurology Haaglanden Medical CentreDen HaagThe Netherlands Radiology Haaglanden Medical CentreDen HaagThe Netherlands Neurology Amsterdam University Medical CentreLocation AMCAmsterdamThe Netherlands Radiology Leiden University Medical CentreLeidenThe Netherlands Radiology Maastricht University Medical Centre+MaastrichtThe Netherlands

background Randomised controlled trials with perfusion selection have shown benefit of endovascular treatment(EVT)for ischaemic stroke between 6 and 24 hours after symptom onset or time last seen ***,outcomes after EVT in these late window patients without perfusion imaging are largely *** assessed their characteristics and outcomes in routine clinical *** The Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands Registry,a prospective,multicentre study in the Netherlands,included patients with an anterior circulation occlusion who underwent EVT between 2014 and *** perfusion was no standard imaging *** used adjusted ordinal logistic regression analysis to compare patients treated within versus beyond 6.5 hours after propensity score matching on age,prestroke modified Rankin Scale(mRS),National Institutes of Health Stroke Scale,Alberta Stroke Programme Early CT Score(ASPECTS),collateral status,location of occlusion and treatment with intravenous *** included 3-month mRS score,functional independence(defined as mRS 0-2),and *** Of 3264 patients who underwent EVT,106(3.2%)were treated beyond 6.5 hours(median 8.5,IQR 6.9-10.6),of whom 93(87.7%)had unknown time of stroke *** perfusion was not performed in 87/106(80.2%)late window *** window patients were younger(mean 67 vs 70 years,pbut better collateral status(collateral score 2-3:68.3%vs 57.7%,p=0.03).No differences were observed in proportions of functional independence(43.3%vs 40.5%,p=0.57)or death(24.0%vs 28.9%,p=0.28).After matching,outcomes remained similar(adjusted common OR for 1 point improvement in mRS 1.04,95%CI 0.56 to 1.93).Conclusions Without the use of CT perfusion selection criteria,EVT in the 6.5-24-hour time window was not associated with poorer outcome in selected patients with favourable clinical and CT/C

关键词： treatment beyond Registry