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Bounded type Siegel disks of finite type maps with few singular values Dedicated to the Memory of Professor Lei Tan

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Science china Mathematics 2018年第12期61卷 2139-2156页

作者： Arnaud chéritat Adam Lawrence Epstein CNRS Institut de Mathematiques de ToulouseUniversite Paul SabatierToulouse F-31062France Mathematics Institute University of WarwickCoventry CV47ALUK

Let U be an open subset of the Riemann sphere C. We give sufficient conditions for which a finite type map f : U →C with at most three singular values has a Siegel disk compactly contained in U and whose boundary is a quasicircle containing a unique critical point. The main tool is quasiconformal surgery à la Douady-Ghys-Herman-(S′)wia tek. We also give sufficient conditions for which, instead, ? has not compact closure in U. The main tool is the Schwarzian derivative and area inequalities à la Graczyk-(S′)wia tek.

关键词： Siegel disks quasicircles quasiconformal surgery Schwarzian derivative

Features of near-inertial motions observed on the northern South china Sea shelf during the passage of two typhoons

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Acta Oceanologica Sinica 2015年第1期34卷 38-43页

作者： chEN Shengli HU Jianyu POLTON jeff.A. State Key Laboratory of Marine Environmental Science College of Ocean & Earth SciencesXiamen University National Oceanography Centre Liverpool L3 5DAUK

Features of near-inertial motions on the shelf （60 m deep） of the northern South china Sea were observed under the passage of two typhoons during the summer of 2009. There are two peaks in spectra at both sub-inertial and super-inertial frequencies. The super-inertial energy maximizes near the surface, while the sub-inertial energy maximizes at a deeper layer of 15 m. The sub-inertial shift of frequency is induced by the negative background vorticity. The super-inertial shift is probably attributed to the near-inertial wave propagating from higher latitudes. The near-inertial currents exhibit a two-layer pattern being separated at mid-depth （25-30 m）, with the phase in the upper layer being nearly opposite to that in the lower layer. The vertical propagation of phase implies that the near-inertial energy is not dominantly downward. The upward flux of the near-inertial energy is more evident at the surface layer （〈17 m）. There exist two boundaries at 17 and 40 rn, where the near-inertial energy is reflected upward and downward. The near-inertial motion is intermittent and can reach a peak of as much as 30 cm/s. The passage of Typhoon Nangka generates an intensive near-inertial event, but Typhoon Linfa does not. This difference is attributed to the relative moor- ing locations, which is on the right hand side of Nangka＇s path （leading to a wind pattern rotating clockwise with time） and is on the left hand side of Linfa＇s path （leading to a wind pattern rotating anti-clockwise with time）.

关键词： near-inertial motions typhoon South china Sea

Modifications of ALPPS–from complex to more complex or from complex to less complex operations

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Hepatobiliary & Pancreatic Diseases International 2017年第4期16卷 346-352页

作者： Wan Yee Lau Eric ch Lai Faculty of Medicine The Chinese University of Hong KongShatinNew TerritoriesHong Kong SARChina Department of Surgery Pamela Youde Nethersole Eastern HospitalHong Kong SARChina

BACKGROUND: Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) has recently been developed to induce rapid liver hypertrophy to reduce the chance of post-hepatectomy liver failure in patients with borderline or insufficient future liver remnant. ALPPS is still in an early developmental stage and its techniques have not been standardized. This study aimed to review the technical modifications of the conventional ALPPS procedure. DATA SOURCES: Studies were identified by searching MEDLINE and PubMed for articles published from January 2007 to December 2016 using the keywords 'associating liver partition and portal vein ligation for staged hepatectomy' and 'ALPPS'. Additional articles were identified by a manual search of references from key articles. RESULTS: There have been a lot of modifications of the conventional ALPPS. These are classified as: (1) modifications aiming to improve surgical results; (2) modifications aiming to expand surgical indications; (3) salvage ALPPS; (4) ALPPS using the minimally invasive approach. Some of these modifications have made the conventional ALPPS procedure to become even more complex, although there have also been other attempts to make the procedure less complex. The results of most of these modifications have been reported in small case series or case reports. We need better well-designed studies to establish the true roles of these modifications. However, it is interesting to see how this conventional ALPPS procedure has evolved since its introduction. CONCLUSIONS: There is a trend for the use of minimally invasive procedure in the phase 1 or 2 of the conventional ALPPS procedure. Some of these modifications have expanded the use of ALPPS in patients who have been considered to have unresectable liver tumors. The long-term oncological outcomes of these modifications are still unknown.

关键词： associating liver partition and portal vein ligation for stage hepatectomy hepatocellular carcinoma hepatectomy liver metastasis portal vein embolization

Fe3O4 nanoparticles impregnated eggshell as a novel catalyst for enhanced biodiesel production

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chinese Journal of chemical Engineering 2019年第11期27卷 2835-2843页

作者： ch.chingakham Asha David V.Sajith School of Nano Science and Technology National Institute of Technology CalicutIndia Malabar christian College CalicutIndia

Biodiesel is a green fuel which can replace diesel while addressing various issues such as scarcity of hydrocarbon fuels and environmental pollution to an extent. The high production cost of biodiesel and the recovery of the catalyst after the transesterification process are the major challenges to be addressed in biodiesel production. In the present work, a cheap and promising solid base oxide catalyst was synthesized from chicken eggshell by calcination at 900 ℃ forming catalyst eggshells(CES) and was impregnated with the nanomagnetic material(Fe3O4) to obtain Fe3O4 loaded catalytic eggshell(CES–Fe3O4). Fe3O4 nanomaterials were synthesized by co-precipitation method and were loaded in catalytic eggshell by sonication, for better recovery of the catalyst after transesterification process. CES–Fe3O4 material was characterized by Thermogravimetric analysis, X-ray diffraction, Fourier transform infrared spectroscopy, a vibrating-sample magnetometer, Brunauer-Emmett-Teller, Dynamic light scattering, and Scanning electron microscopy. Biodiesel was synthesized by transesterification of Pongamia pinnata raw oil with 1:12 oil to methanol molar ratio and 2 wt% catalyst loading for 2 h at a temperature of 65 ℃ and yields were compared. The reusability of the catalyst was studied by the transesterification of the raw oil and its catalytic activity was found to be retained up to 7 cycles with a yield of 98%.

关键词： Catalyst Biodiesel Nanoparticles Fe3O4 Impregnation Transesterification

SEQUENTIAL CONVEX PROGRAMMING METHODS FOR SOLVING LARGE TOPOLOGY OPTIMIZATION PROBLEMS： IMPLEMENTATION AND COMPUTATIONAL RESULTS

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Journal of Computational Mathematics 2005年第5期23卷 491-502页

作者： Qin Ni ch.Zillober K.Schittkowski Nanjing University of Aeronautics and Astronautics 210016 Nanjing China Department of Computer Science University of BayreuthD-95440 BayreuthGermany

In this paper, we describe a method to solve large-scale structural optimization problems by sequential convex programming （SCP）. A predictor-corrector interior point method is applied to solve the strictly convex subproblems. The SCP algorithm and the topology optimization approach are introduced. Especially, different strategies to solve certain linear systems of equations are analyzed. Numerical results are presented to show the efficiency of the proposed method for solving topology optimization problems and to compare different variants.

关键词： Large scale optimization Topology optimization Sequential convex programming method Predictor-corrector interior point method Method of moving asymptotes

Skeletal phenotypes in secreted frizzled-related protein 4 gene knockout mice mimic skeletal architectural abnormalities in subjects with Pyle's disease from SFRP4 mutations

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Bone Research 2023年第1期11卷 193-200页

作者： Robert Brommage jeff.Liu David R.Powell Department of Metabolism Research Lexicon PharmaceuticalsThe WoodlandsTX77381USA

Mutations in SFRP4 cause Pyle’s bone disease with wide metaphyses and increased skeletal *** WNT signaling pathway plays important roles in determining skeletal architecture and SFRP4 is a secreted Frizzled decoy receptor that inhibits WNT *** cohorts of male and female Sfrp4 gene knockout mice,examined through 2 years of age,had a normal lifespan but showed cortical and trabecular bone *** human Erlenmeyer flask deformities,bone cross-sectional areas were elevated 2-fold in the distal femur and proximal tibia but only 30%in femur and tibia *** cortical bone thickness was observed in the vertebral body,midshaft femur and distal *** trabecular bone mass and numbers were observed in the vertebral body,distal femur metaphysis and proximal tibia *** femurs retained extensive trabecular bone through 2 years of *** bodies had increased compressive strength,but femur shafts had reduced bending ***,but not cortical,bone parameters in heterozygous Sfrp4mice were modestly *** resulted in similar declines in both cortical and trabecular bone mass in wild-type and Sfrp4 KO ***4 is critical for metaphyseal bone modeling involved in determining bone ***4 KO mice show similar skeletal architecture and bone fragility deficits observed in patients with Pyle’s disease with SFRP4 mutations.

关键词： SFRP4 skeletal elevated

Estimating rock properties using sound signal dominant frequencies during diamond core drilling operations

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第4期11卷 850-859页

作者： ch.Vijaya Kumar Harsha Vardhan ch.S.N.Murthy N.C.Karmakar Department of Mining Engineering National Institute of Technology KarnatakaSurathkalIndia Indian Institute of Technology (BHU) VaranasiIndia

In many engineering applications such as mining,geotechnical and petroleum industries,drilling operation is widely *** drilling operation produces sound by-product,which could be helpful for preliminary estimation of the rock ***,determination of rock properties is very difficult by the conventional methods in terms of high accuracy,and thus it is expensive and *** this context,a new technique was developed based on the estimation of rock properties using dominant frequencies from sound pressure level generated during diamond core drilling ***,sound pressure level was recorded and sound signals of these sound frequencies were analyzed using fast Fourier transform (FFT).Rock drilling experiments were performed on five different types of rock samples using computer numerical control (CNC) drilling machine BMV 45 *** simple linear regression analysis,mathematical equations were developed for various rock properties,*** compressive strength,Brazilian tensile strength,density,and dominant frequencies of sound pressure *** developed models can be utilized at early stage of design to predict rock properties.

关键词： Rock properties Sound pressure level Fast Fourier transform (FFT) Sound signal Core drilling Dominant frequencies

ENHANCEMENT　OF　INTRAMOLECULAR　EXCIMER　FORMATION　AND　PHOTODIMERIZATION　OF　POLYETHERS　BEARING　NAPHTHALENE　chROMOPHORES　VIA　COMPLEXATION　WITH　CATIONS

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chinese chemical Letters 1995年第2期6卷 113-116页

作者： Tung, ch Wu, LZ Acad Sinica Inst Photog Chem Beijing 100101 Peoples R China

The fluorescence spectra and photodimerization of naphthalene end-laballed poly(ethylene glycol) oligomers (N-Pn-N) in methanol in the prescence of alkali cations have been investigated. The ion enhances or inhibits intramolecular excimer formation and photodimerization of N-Pn-N, depending on the size of the ion and the length of the polyether chain. This observation suggests that the polyether chain binds the ion, thus adopts a crown ether-like conformation.

关键词： VIA chROMOPHORES COMPLEXATION WITH NAPHTHALENE AND BEARING

Complex dynamics and bifurcation analysis for a Beverton-Holt population model with Allee effect

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International Journal of Biomathematics 2023年第7期16卷 165-196页

作者： Karima Mokni Mohamed ch-chaoui MRI Laboratory FacultéPolydisciplinaire Khouribga Sultan Moulay Slimane University BP:145 Khouribga Principale25000Kingdom of Morocco

In this paper,we have derived a discrete evolutionary Beverton-Holt population *** model is built using evolutionary game theory methodology and takes into consideration the strong Allee effect related to predation *** have discussed the existence of the positive fixed point and examined its asymptotic ***,we demonstrated that the derived model exhibits Neimark-Sacker bifurcation when the maximal predator intensity is at lower *** chaotic behaviors are justified ***,to avoid these chaotic features and achieve asymptotic stability,we implement two chaos control methods.

关键词： Evolutionary game theory asymptotic stability Neimark-Sacker bifurcation chaos control