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meyer-neldel Rule in Plasma Polythiophene Thin Films

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Open journal of Polymer Chemistry 2014年第3期4卷 31-37页

作者： j. Cuauhtemoc Palacios m. Guadalupe Olayo Guillermo j. Cruz j. A. Chávez-Carvayar Departamento de Física Instituto Nacional de Investigaciones Nucleares Ocoyoacac México Facultad de Ingeniería Universidad Autónoma del Estado de México Toluca México.

In polymers, the electronic activation energy depends on the fragmentation, crosslinking, dopants, moisture and in general on the structure-environment interaction. This has a special importance in plasma polymers because fragmentation and crosslinking are usually higher than in other polymers. In this work, DC electrical conductivity of polythiophene thin films prepared by plasma (pPTh) was studied using the meyer-neldel (mn) rule to calculate the characteristic mn energy and temperature as a function of moisture and metallic dopants. The experimental data for pPTh synthesized in different conditions indicated that Em = 32 meV and Tm = 373 K, suggesting a thermally activated conduction mechanism;however, in polymer-metal matrices with metal concentration higher than the percolation threshold, the conduction mechanism is different causing that the mn rule was only partially fulfilled. The congruence of the experimental data with the multiexcitation entropy model is discussed.

关键词： Polythiophene Plasma Conductivity meyer-neldel Rule multi-Excitation Entropy model

Antibacterial approaches in tissue engineering using metal ions and nanoparticles:From mechanisms to applications

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Bioactive materials 2021年第12期6卷 4470-4490页

作者： maria Godoy-Gallardo Ulrich Eckhard Luis m.Delgado Yolanda j.D.de Roo Puente mireia Hoyos-nogués F.javier Gil Roman A.Perez Bioengineering Institute of Technology Universitat Internacional de CatalunyaCarrer de Josep Trueta08195del VallèsSant CugatBarcelonaSpain Proteolysis Lab Department of Structural BiologyMolecular Biology Institute of BarcelonaCSICBarcelona Science ParkBaldiri Reixac 15-2108028BarcelonaSpain

Bacterial infection of implanted scaffolds may have fatal consequences and,in combination with the emergence of multidrug bacterial resistance,the development of advanced antibacterial biomaterials and constructs is of great *** decades ago,metals and their ions had been used to minimize bacterial infection risk and,more recently,metal-based nanomaterials,with improved antimicrobial properties,have been advocated as a novel and tunable alternative.A comprehensive review is provided on how metal ions and ion nanoparticles have the potential to decrease or eliminate unwanted *** mechanisms such as oxidative stress induction,ion release and disruption of biomolecules are currently well ***,the exact antimicrobial mechanisms of the discussed metal compounds remain poorly *** combination of different metal ions and surface decorations of nanoparticles will lead to synergistic effects and improved microbial killing,and allow to mitigate potential side effects to the *** with a general overview of antibacterial mechanisms,we subsequently focus on specific metal ions such as silver,zinc,copper,iron and gold,and outline their distinct modes of ***,we discuss the use of these metal ions and nanoparticles in tissue engineering to prevent implant failure.

关键词： metal ions metal nanoparticles mechanism of action Antibacterial activity Tissue engineering Biomaterials applications

Optimizing the use of open chambers to measure ammonia volatilization in field plots amended with urea

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Pedosphere 2021年第2期31卷 243-254页

作者： márcio R.mARTInS Leonardo F.SARKIS Selenobaldo A.C.SAnT’AnnA Camila A.SAnTOS Karla E.ARAUjO Ricardo C.SAnTOS Ednaldo S.ARAÚjO Bruno j.R.ALVES Claudia P.jAnTALIA Robert m.BODDEY mohammad ZAmAn Segundo URQUIAGA Embrapa Agrobiology Rod.BR 465km 7Seropédica RJ CEP 23891-000(Brazil) Federal Rural University of Rio de janeiro(UFRRj) Rod.BR 465km 7Seropédica RJ CEP 23891-000(Brazil) Agroscope Research Division Agroecology and EnvironmentClimate and Agriculture GroupReckenholzstrasse 191Zurich 8046(Switzerland) Soil and Water management&Crop nutrition Joint FAO/IAEA Division of Nuclear Techniques in Food&AgricultureP.O.Box 100Vienna A-1400(Austria)

measuring ammonia(nH_(3))volatilization from urea-fertilized soils is crucial for evaluation of practices that reduce gaseous nitrogen(n)losses in *** small area of chambers used for nH_(3)volatilization measurements compared with the size of field plots may cause significant errors if inadequate sampling strategies are *** aims were:i)to investigate the effect of using multiple open chambers on the variability in the measurement of nH_(3)volatilization in urea-amended field plots and ii)to define the critical period of nH_(3)-n losses during which the concentration of sampling effort is capable of reducing *** use of only one chamber covering 0.015%of the plot(51.84 m^(2))generates a value of nH_(3)-n loss within an expected margin of error of 30%around the true *** reduce the error margin by half(15%),3–7 chambers were required with a mean of 5 chambers per *** the sampling efforts in the first two weeks after urea application,which is usually the most critical period of n losses and associated errors,represents an efficient strategy to lessen uncertainty in the measurements of nH_(3)*** strategy enhances the power of detection of nH_(3)-n loss abatement in field experiments using chambers.

关键词： chamber method experimental error gas emission low-cost chamber nitrogen cycling nitrogen loss soil variability

non-pharmacological management of pediatric functional abdominal pain disorders:Current evidence and future perspectives

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World journal of Clinical Pediatrics 2022年第2期11卷 105-119页

作者： maria Luísa Cordeiro Santos Ronaldo Teixeira da Silva júnior Breno Bittencourt de Brito Filipe Antônio França da Silva Hanna Santos marques Vinícius Lima de SouzaGonçalves Talita Costa dos Santos Carolina Ladeia Cirne natália Oliveira e Silva márcio Vasconcelos Oliveira Fabrício Freire de melo Instituto multidisciplinar em Saúde Universidade Federal da BahiaVitória da Conquista 45029-094BahiaBrazil Campus Vitória da Conquista Universidade Estadual do Sudoeste da BahiaVitória da Conquista 45083-900BahiaBrazil

Functional abdominal pain disorders(FAPDs) are an important and prevalent cause of functional gastrointestinal disorders among children, encompassing the diagnoses of functional dyspepsia, irritable bowel syndrome, abdominal migraine, and the one not previously present in Rome Ⅲ, functional abdominal pain not otherwise specified. In the absence of sufficiently effective and safe pharmacological treatments for this public problem, non-pharmacological therapies emerge as a viable means of treating these patients, avoiding not only possible side effects, but also unnecessary prescription, since many of the pharmacological treatments prescribed do not have good efficacy when compared to placebo. Thus, the present study provides a review of current and relevant evidence on non-pharmacological management of FAPDs, covering the most commonly indicated treatments, from cognitive behavioral therapy to meditation, acupuncture, yoga, massage, spinal manipulation, moxibustion, and physical activities. In addition, this article also analyzes the quality of publications in the area, assessing whether it is possible to state if non-pharmacological therapies are viable, safe, and sufficiently well-based for an appropriate and effective prescription of these treatments. Finally, it is possible to observe an increase not only in the number of publications on the non-pharmacological treatments for FAPDs in recent years, but also an increase in the quality of these publications. Finally, the sample selection of satisfactory age groups in these studies enables the formulation of specific guidelines for this age group, thus avoiding the need for adaptation of prescriptions initially made for adults, but for children use.

关键词： Functional abdominal pain disorder Pediatrics Rome IV Behavioral intervention nonpharmacological treatment Complementary medicine

比利时UGInE&ALZ新建不锈钢厂投产一年的运行情况

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钢铁 2004年第5期39卷 26-29页

作者： j.Steins S.Dimitrov m.Hiebler j.Krumenacker m.Thalhammer O.Schulz 奥钢联工程技术公司

20 0 0年 1 1月奥钢联从比利时 AL Z获得将其不锈钢产能提高 1倍、达到 1 2 0万 t/a的合同。

关键词：不锈钢电弧炉 AOD 板坯连铸环保

Procedural complexity independent of P2Y12 reaction unit(PRU)values is associated with acute in situ thrombosis in Pipeline flow diversion of cerebral aneurysms

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Stroke & Vascular neurology 2018年第3期3卷 169-175页

作者： Bowen jiang matthew T Bender Erick m Westbroek jessica K Campos Li-mei Lin Risheng Xu Rafael j Tamargo judy Huang Geoffrey P Colby Alexander L Coon Department of neurosurgery Johns Hopkins University School of MedicineBaltimoreMarylandUSA Department of neurosurgery University of CaliforniaIrvine School of MedicineOrangeCaliforniaUSA Department of neurosurgery University of CaliforniaLos AngelesLos AngelesCaliforniaUSA

background Acute in situ thrombosis is an ischaemic phenomenon during Pipeline embolisation device(PED)procedures with potentially high morbidity and *** is controversy regarding the role of platelet function testing with P2Y12 assay as a predictor of intraprocedural thromboembolic *** is limited knowledge on whether procedural complexity influences these *** Data were collected retrospectively on 742 consecutive PED cases at a single *** with intraprocedural acute thrombosis were compared with patients without these *** A cohort of 37 PED cases with acute in situ thrombosis(mean age 53.8 years,mean aneurysm size 8.4 mm)was matched with a cohort of 705 PED cases without intraprocedural thromboembolic events(mean age 56.4 years,mean aneurysm size 6.9 mm).All patients with in situ thrombosis received intra-arterial and/or intravenous *** two groups were evenly matched in patient demographics,previous treatment/subarachnoid hemorrhage(SAH)and aneurysm *** was no statistical difference in postprocedural P2Y12 reaction unit(PRU)values between the two groups,with a mean of 156 in the in situ thrombosis group vs 148 in the control group(p=0.5894).Presence of cervical carotid tortuosity,high cavernous internal carotid artery grade,need for multiple PED and vasospasm were not significantly different between the two *** in situ thrombosis group had statistically significant longer fluoroscopy time(60.4 vs 38.4 min,pn exposure(3476 vs 2160 mGy,pjunctive coiling(24.3% vs 8.37%,p=0.0010)and higher utilisation of balloon angioplasty(37.8% vs 12.2%,pnically,the in situ thrombosis cohort had higher incidence of major and minor stroke,intracerebral haemorrhage and length of *** Predictors of procedural complexity(higher radiation exposure,longer fluoroscopy time,adjunctive coiling and need for balloon angioplasty)are asso

关键词： P2Y12 matched balloon

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激光熔区中应力缓解的X射线衍射法测定

金属学报 1993年第9期29卷 B428-B432页

作者：徐景阳 VAnBRUSSEL B j nOORDHUIS j BROnSVELD Pm DEHOSSOnj Th m 中国科学院上海冶金研究所荷兰Groningen大学

AISI 304奥氏体不锈钢表面经激光熔化处理,引入一个大的张应力,它可用注ne的方法使其缓解本文介绍测量0.1μm薄层应力变化的原理和技术。

关键词：奥氏体不锈钢 X射线衍射测量应力

Enhancements to modified Chebyshev-Picard Iteration Efficiency for Perturbed Orbit Propagation

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Computer modeling in Engineering & Sciences 2016年第1期111卷 29-64页

作者： B.macomber A.B.Probe R.Woollands j.Read j.L.junkins Texas A&m University College StationTXUSA.

modified Chebyshev Picard Iteration is an iterative numerical method for solving linear or non-linear ordinary differential *** a serial computational environment the method has been shown to compete with,or outperform,current state of practice numerical *** paper presents several improvements to the basic method,designed to further increase the computational efficiency of solving the equations of perturbed orbit propagation.

关键词： Astrodynamics Orbit Propagation Cheybshev Polynomials Picard Iteration.

孕16～21周的人绒毛膜促性腺激素水平及其对先兆子痫的预测

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世界核心医学期刊文摘（妇产科学分册） 2006年第5期2卷 54-55页

作者： Roiz-Herná ndez j Cabello-martnez j.D.j Ferná n-dez-meja m 柳蕴 Unidad de Investigació n Clnica Torreó n Coahuila Mexico

To determine whether levels of beta human choriogonadotropin (β - hCG) during the second trimester are a predictor of pre-eclampsia. methods. A prospective study of 784 women was conducted between their 16th and 20th week of pregnancy. Primigravidas and multigravidas were analyzed separately, and the cutoff point was determined using a receiver operating characteristic curve. The accuracy of β - hCG levels in the prediction of preecla-mpsiawas evaluated. The likelihood ratios were calculated for different levels of β - hCG in both groups. Results. Pre-eclampsia prevalence was 7.1% among primigravidas and 4.6% among multigravidas. The cutoff concentration was 2.0 mom in both groups. For primigravidas and multigravidas, respectively, the area below the curve was 0.96 and 0.95; sensitivity was 88.5% and 100% ; specificity was 92.0% and 85.6% ; positive predictive value was 0.46 and 0.25; and negative predictive value was 0.99 and 1.0. With a cutoff concentration of 2.0 mom of β - hCG, the positive likelihood ratio was 11.1 in primigravidas and 6.9 in multigravidas. Conclusion. This study shows that measuring levels of β - hCG during the second trimester of pregnancy is useful in clinical practice to identify pregnant women who will develop pre-eclampsia.

关键词：先兆子痫妊娠中期经孕妇初孕妇阳性似然比阴性预测值阳性预测值界值特征曲线特异度