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THE FEKETE-SZEG PROBLEM FOR CLOSE-TO-CONVEX FUNCTIONS WITH RESPECT TO THE KOEBE FUNCTION

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Acta Mathematica Scientia 2014年第5期34卷 1571-1583页

作者： Bogumila KOWALCZYK adam LECKO Chair of Complex Analysis University of Warmia and Mazury ul. S loneczna 5410710 Olsztyn Poland

An analytic function f in the unit disk D ：= {z ∈ C ：｜z｜〈 1}, standardly normalized, is called close-to-convex with respect to the Koebe function k（z）：= z/（1-z）2, z ∈ D, if there exists δ ∈ （-π/2,π/2） such that Re {eiδ（1-z）2f′（z）} 〉 0, z ∈ D. For the class C（k） of all close-to-convex functions with respect to k, related to the class of functions convex in the positive direction of the imaginary axis, the Fekete-Szego problem is studied.

关键词： Fekete-Szego problem close-to-convex functions close-to-convex functionswith respect to the Koebe function close-to-convex functions with argumentδ functions convex in the positive direction of the imaginary axis

A Three-Dimensional Kinematics Analysis of a Koi Carp Pectoral Fin by Digital Image Processing

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Journal of Bionic Engineering 2013年第2期10卷 210-221页

作者： Lei Wang Min Xu Bo Liu Kin Huat low Jie Yang Shiwu Zhang Department of Precision Machinery and Precision Instrumentation University of Science and Technology of China Hefei Anhui 230026 P. R. China School of Mechanical and Aerospace Engineering Nanyang Technological University Singapore 639798 Singapore

Pectoral fins fascinate researchers for their important role in fish maneuvers. By possessing a complicated flexible structure with several fin rays made by a thin film, the fin exhibits a three-dimensional （3D） motion. The complex 3D fin kinematics makes it challenging to study the performance of pectoral fin. Nevertheless, a detailed study on the 3D motion pattern of pectoral fins is necessary to the design and control ofa bio-inspired fin rays. Therefore, a highspeed photography system is introduced in this paper to study the 3D motion ofa Koi Carp by analyzing the two views of its pectoral fin simultaneously. The key motions of the pectoral fins are first captured in both hovering and retreating. Next, the 3D configuration of the pectoral fins is recon- structed by digital image processing, in which the movement of fin rays during fish retreating and hovering is obtained. Fur- thermore, the method of Singular Value Decomposition （SVD） is adopted to extract the basic motion patterns of pectoral fins from extensive image sequences, i.e. expansion, bending, cupping, and undulation. It is believed that the movement of the fin rays and the basic patterns of the pectoral fins obtained in the present work can provide a good foundation for the development and control of bionic flexible pectoral fins for underwater propeller.

关键词： highspeed photography Singular Value Decomposition (SVD) three-dimensional kinematics digital image proc-essing

Hepatocellular carcinoma:Defining the place of surgery in an era of organ shortage

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World Journal of Gastroenterology 2008年第28期14卷 4445-4453页

作者： adam Bartlett Nigel Heaton Institute of Liver Studies Kings College School of Medicine at Kings College HospitalDenmark HillCamberwellLondonSE5 9RSUnited Kingdom

Liver resection (LR) and transplantation offer the only potential chance of cure for patients with hepatocellular carcinoma (HCC). Historically, all patients were treated by hepatic resection. With the advent of liver transplantation (LT) patients with HCC were preferentially placed on the waiting list for LT. However, early experience with LT was associated with a high rate of tumour recurrence and poor long-term survival. The increasing scarcity of donor livers resulted in restrictions being placed on tumour size, and an improvement in patient survival. To date there have been no randomised clinical trials comparing LR to LT. We review the evidence supporting LR and/or LT for HCC and discuss the role of neoadjuvant therapy. The decision of whether to resect or transplant remains debatable and is often determined by centre experience, availability of LT and donor organs.

关键词： Hepatocellular carcinoma Liver transplantation Liver resection Adjuvant therapy Salvage liver transplantation Radiofrequency ablation Transarterial chemoembolization

CONVERGENCE RATES FOR DIFFERENCE SCHEMES FOR POLYHEDRAL NONLINEAR PARABOLIC EQUATIONS

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Journal of Computational Mathematics 2010年第4期28卷 474-488页

作者： adam M.Oberman Department of Mathematics Simon Fraser University

We build finite difference schemes for a class of fully nonlinear parabolic equations. The schemes are polyhedral and grid aligned. While this is a restrictive class of schemes, a wide class of equations are well approximated by equations from this class. For regular （C2,α） solutions of uniformly parabolic equations, we also establish of convergence rate of O（α）. A case study along with supporting numerical results is included.

关键词： Error estimates Convergence rate Viscosity solutions Finite difference schemes

A Reduced-Form Rapid Economic Consequence Estimating Model:Application to Property Damage from U.S. Earthquakes

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International Journal of Disaster Risk Science 2013年第1期4卷 20-32页

作者： Nathaniel Heatwole adam Rose National Center for Risk and Economic Analysis of Terrorism Events(CREATE) University of Southern CaliforniaLos AngelesCA 90089USA Price School of Public Policy University of Southern CaliforniaLos AngelesCA 90089USA

Modeling the economic consequences of disasters has reached a high level of maturity and accuracy in recent years. Methods for providing reasonably accurate rapid estimates of economic losses, however, are still limited. This article presents the case for “reduced-form” models for rapid economic consequence estimation for disasters, and specifies and statistically estimates a regression equation for property damage from significant U.S. earthquakes. Explanatory variables are of two categories:(1) hazard-related variables pertaining to earthquake characteristics;and(2) exposure-related variables pertaining to socioeconomic conditions. Comparisons to other available earthquake damage estimates indicate that our Reduced-Form Model yields reasonably good results, including several statistically significant variables that are consistent with a priori hypotheses. The article concludes with a discussion of how the research can be enhanced through the collection of data on additional variables, and of the potential for the extension of the reduced-form modeling approach to other hazard types.

关键词： earthquake hazard maturity

Sharp Heat Kernel Estimates in the Fourier–Bessel Setting for a Continuous Range of the Type Parameter

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Acta Mathematica Sinica,English Series 2014年第3期30卷 437-444页

作者： adam NOWAK Luz RONCAL Instytut Matematyczny Polska Akademia Nauk Departamento de Matemáticas y Computación Universidad de La Rioja

The heat kernel in the setting of classical Fourier-Bessel expansions is defined by an os- cillatory series which cannot be computed explicitly. We prove qualitatively sharp estimates of this kernel. Our method relies on establishing a connection with a situation of expansions based on Jacobi polynomials and then transferring known sharp bounds for the related Jacobi heat kernel.

关键词： Fourier-Bessel expansions heat kernel Bessel process transition density

Expanding roles for pectins in plant development

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Journal of Integrative Plant Biology 2018年第10期60卷 910-923页

作者： adam M.Saffer Department of Molecular Cellular and Developmental BiologyYale University

Pectins are complex cell wall polysaccharides important for many aspects of plant development. Recent studies have discovered extensive physical interactions between pectins and other cell wall components,implicating pectins in new molecular functions. Pectins are often localized in spatially-restricted patterns, and some of these non-uniform pectin distributions contribute to multiple aspects of plant development, including the morphogenesis of cells and organs. Furthermore, a growing number of mutants affecting cell wall composi- tion have begun to reveal the distinct contributions of different pectins to plant development. This review discusses the interactions of pectins with other cell wall components, the functions of pectins in controlling cellular morphology, and how non-uniform pectin composition can be an important determinant of developmental processes.

关键词： Expanding roles for pectins in plant development

Impact of a new aggressive nutrition policy incorporating early introduction of parenteral nutrition and mother's own milk on growth of preterm infants

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世界儿科杂志:英文版 2016年第4期12卷 450-454页

作者： Chuen Siang low Jacqueline J Ho Revathy Nallusamy Penang Medical College Penang 10450Malaysia Department of Pediatrics Penang Medical CollegePenangMalaysia Department of Pediatrics Penang HospitalPenangMalaysia

Background:Most of the evidence on early feeding of preterm infants was derived from high income settings,it is equally important to evaluate whether it can be successfully implemented into less resourced *** study aimed to compare growth and feeding of preterm infants before and after the introduction of a new aggressive feeding policy in Penang Hospital,a tertiary referral hospital in a middle income ***:The new aggressive feeding policy was developed mainly from Cochrane review evidence,using early parenteral and enteral nutrition with standardized breastfeeding counselling aimed at empowering mothers to provide early expressed milk.A total of 80 preterm babies(34 weeks and below)discharged from NICU were included(40 pre-and 40 post-intervention).Pre and post-intervention data were *** primary outcome was growth at day 7,14,21 and at discharge and secondary outcomes were time to full oral feeding,breastfeeding rates,and adverse ***:Complete data were available for all babies to *** baby was discharged prior to day 14 and 10 babies before day 21,so growth data for these babies were *** data were similar in the two *** was no significant weight difference at 7,14,21 days and at *** post-intervention babies were breastfed at discharge than pre-intervention babies(21 vs.8,P=0.005).Nosocomial infection(11 vs.4,P=0.045),and blood transfusion were significantly lower in the postintervention babies than in the pre-intervention babies(31 vs.13,P=0.01).The post-intervention babies were more likely to achieve shorter median days(interquartile range)to full oral feeding[11(6)days vs.13(11)days,P=0.058]and with lower number affecting necrotising enterocolitis(0 vs.5,P=0.055).Conclusion:Early aggressive parenteral nutrition and early provision of mother’s milk did not result in improved growth as evidenced by weight gain at *** we found more breastfeeding babies,lower nosocom

关键词： early breastfeeding early parenteral nutrition pediatrics preterm babies

POTENTIAL OPERATORS AND LAPLACE TYPE MULTIPLIERS ASSOCIATED WITH THE TWISTED LAPLACIAN

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Acta Mathematica Scientia 2017年第1期37卷 280-292页

作者： adam NOWAK Krzysztof STEMPAK Instytut Matematyczny Polska Akademia NaukSniadeckich 800-656 WarszawaPoland Wydziat Matematyki Politechnika WroctawskaWyb.Wyspianskiego 2750-370 WroclawPoland

We study potential operators and,more generally,Laplace-Stieltjes and Laplace type multipliers associated with the twisted *** characterize those 1 ≤ p,q ≤ ∞,for which the potential operators are Lp—Lq *** result is a sharp analogue of the classical Hardy-Littlewood-Sobolev fractional integration theorem in the context of special Hermite *** also investigate Lp mapping properties of the Laplace-Stieltjes and Laplace type multipliers.

关键词： twisted Laplacian special Hermite expansion negative power potential op-erator fractional integral potential kernel spectral multiplier singular oscil-latory integral