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New Hormaphididae(Hemiptera,Aphidomorpha) from the Baltic Amber and its Palaeogeographic Significance

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Acta Geologica Sinica(English Edition) 2011年第3期85卷 521-527页

作者： piotr WEGIEREK Dagmara ZYLA Department of Zoology University of Silesia 40-007 KatowicePoland

The present study describes a new genus and species Unicohormaphis sorini,which belongs to the subfamily *** contemporary distribution of aphids belonging to the Hormaphididae family is summarized and *** to the obtained data,the climate warming in Eocene was conducive to the expansion of the family over the areas of *** climate changes,resulting from epeirogenic and orogenic movements towards the end of Eocene,led to a considerable cooling and drying of climate in the northern *** processes contributed to the shrinking down of areas covered by subtropical forests,which constituted the habitat of Hormaphididae（Cerataphidinae）.Retaining their way of life,the Cerataphidinae were forced to limit their distribution,and the representatives of the family in Europe became completely extinct.

关键词： Hemiptera Aphidomorpha Unicohormaphis new genus Baltic amber paleoclimate

Alpha-synuclein preformed fibrils:a tool to understand Parkinson’s disease and develop disease modifying therapy

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Neural Regeneration Research 2021年第11期16卷 2219-2221页

作者： piotr Chmielarz Andrii Domanskyi Institute of Biotechnology HiLIFEUniversity of HelsinkiFinland Maj Institute of Pharmacology Polish Academy of SciencesDepartment of Brain BiochemistryKrakówPoland Orion Corporation Orion Pharma TurkuFinland

Parkinson’s disease(PD)is the second most common neurodegenerative disorder characterized by multiple motor and nonmotor symptoms,which include,among others,constipation,sleep disturbance,bradykinesia,gait and balance abnormalities,muscle stiffness and resting *** motor symptoms are caused by progressive age-related death of dopaminergic neurons and in the vast majority of patients suffering from age-related idiopathic PD the cause of dopaminergic neurodegeneration is *** in the familial early-onset PD where genetic mutations have been identified,the molecular mechanisms driving degeneration of dopaminergic neurons are far from ***,there is no clinically approved disease-modifying therapy capable of stopping or at least slowing down the disease progression.

关键词： degeneration Alpha driving

ON THE DISCRETE MAXIMUM PRINCIPLE FOR THE LOCAL PROJECTION SCHEME WITH SHOCK CAPTURING

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Journal of Computational Mathematics 2017年第5期35卷 547-568页

作者： piotr Skrzypacz Dongming Wei Nazarbayev University School of Science and Technology 53 Kabanbay Batyr Ave. Astana 010000 Kazakhstan

It is a well known fact that finite element solutions of convection dominated problems can exhibit spurious oscillations in the vicinity of boundary layers. One way to overcome this numerical instability is to use schemes that satisfy the discrete maximum principle. There are monotone methods for piecewise linear elements on simplices based on the up- wind techniques or artificial diffusion. In order to satisfy the discrete maximum principle for the local projection scheme, we add an edge oriented shock capturing term to the bilinear form. The analysis of the proposed stabilisation method is complemented with numerical examples in 2D.

关键词： Local projection stabilization Discrete maximum principle Shock capturing

Review and evaluation of cold recycling with bitumen emulsion and cement for rehabilitation of old pavements

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Journal of Traffic and Transportation Engineering(English Edition) 2019年第4期6卷 311-323页

作者： Bohdan Dolzycki piotr Jaskula Department of Highway and Transportation Engineering Gdansk University of Technology

The article presents Polish experience with cold recycling of asphalt pavements with the usage of bituminous emulsion and cement. In the 1990 s numerous roads in Poland required immediate reinforcement due to their significant degradation. Implementation of the cold recycling technology was one of the solutions to this problem. Cold recycled mixtures contain e beside the recycled asphalt pavement and aggregate e two different types of binding agents: bituminous emulsion and Portland cement. First Polish requirements were developed in the 1990 s and were based on the Marshall test. After several years of application of these requirements, numerous transverse cracks appeared on the pavements. Field investigation showed that the frequency of transverse cracking was not uniform on all evaluated sections and that the growth rate of the number of cracks was decreasing. The main reason of extensive cracking was the overly high amount of the Portland cement and insufficient amount of the bituminous emulsion. This led to production of very stiff mixtures, with dominance of hydraulic bonds, which behaved similarly to cement-treated mixtures. The idea of flexible cold recycled base course was not utilized. This experience motivated the Polish Road Administration to develop new requirements. Second part of the article presents the new requirements for cold *** test methods as well as requirements concerning resistance to frost and water action were introduced in 2013. Implementing of the new requirements resulted in significant reduction in stiffness of the MCE mixtures. Values of stiffness modulus are even three times lower, which should significantly decrease the amount of potential reflective cracks on the pavement surface. Presently two types of technology of cold recycling are used in Poland, in-place and in-plant.

关键词： Cold recycling Mineral-cement-emulsion mixtures(MCE) Reflecting cracks Stiffness modulus Road reconstruction Fatigue life of pavement structures

Shock Wave Smearing by Passive Control

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Journal of Thermal Science 2006年第1期15卷 43-47,42页

作者： piotr DOERFFER Oskar SZULC Rainer BOHNING IMP PAN Fiszera 14 PL-80 952 Gdansk Poland ISL Universitat Karlsruhe Karlsruhe Germany

Normal shock wave, terminating a local supersonic area on an airfoil, limits its performance and becomes a source of high speed impulsive noise. It is proposed to use passive control to disintegrate the shock wave. Details of the flow structure obtained by this method are studied numerically. A new boundary condition has been developed and the results of its application are verified against experiments in a nozzle flow. The method of shock wave disintegration has been confirmed and detailed analysis of the flow details is presented. The substitution of a shock wave by a gradual compression changes completely the source of the high speed impulsive noise and bears potential of its reduction.

关键词： transonic flows shock wave boundary layer interaction passive control.

Endoscopic ultrasound-guided drainage of peripancreatic fluid collections: What impacts treatment duration?

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Hepatobiliary & Pancreatic Diseases International 2023年第3期22卷 310-316页

作者： Adam Przybyłkowski piotr Nehring Department of Gastroenterology and Internal Medicine Medical University of WarsawWarsawPoland

Background:Peripancreatic fluid collections(PFCs)are complications resulting from acute or chronic pancreatitis and require treatment in certain clinical *** present study aimed to identify the factors influencing the duration of endoscopic ultrasound(EUS)-guided drainage of symptomatic pancreatic pseudocysts(PPCs),walled-off necrosis(WON),and acute necrotic collections(ANCs).Methods:This was a retrospective cohort study of 68 patients with PFCs who underwent EUS-guided *** timing and duration of EUS-guided drainage of various PFCs(ANC,WON,and PPCs)were compared,and the factors influencing the duration of endoscopic treatment were ***:The mean time to first EUS-guided PFC drainage since the acute pancreatitis episode was 372.0,505.0,and 18.7 days for WON,PPC,and ANC,respectively,and the mean duration of treatment was 90,60,and 63 days,respectively.A disconnected pancreatic duct,a history of percutaneous drainage,and an infected PFC were identified as factors influencing the treatment duration.A positive correlation was observed between the treatment duration and patients’*** with a disconnected pancreatic duct had to undergo more *** patients with PPC,clinically successful drainage was more frequently achieved after a single procedure without the need for repeated procedures than in those with WON(90%vs.59%,P=0.01).Conclusions:Patients with a history of percutaneous drainage,disconnected pancreatic duct,or PFC infection may require longer endoscopic treatment.

关键词： Cyst Drainage Endoscopy Pancreas Pancreatitis

Effect of Jet Vortex Generators on Shock Wave Induced Separation on Gas Turbine Profile

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Journal of Thermal Science 2021年第4期30卷 1435-1443页

作者： FLASZYNSKI Pawel DOERFFER piotr piotrOWICZ Michal Szewalski Institute of Fluid-Flow Machinery Polish Academy of SciencesFiszera 14PL 80-231GdanskPoland

The interaction between a shock wave and a boundary layer on a suction side of gas turbine profile,namely Transition Location Effect on Shock Wave Boundary Layer Interaction,was one of main objectives of TFAST project.A generic test section in a transonic wind tunnel was designed to carry out such *** design criteria were to reproduce flow conditions on the profile in wind tunnel as the one existing on the suction side of the turbine guide *** this paper,the effect of film cooling and jet vortex generators on the shock wave boundary layer interaction and shock induced separation is *** results for Explicit Algebraic Reynolds Stress Model with transition modeling are compared with experimental data.

关键词： shock wave gas turbine flow control jet vortex generators

Streamwise vortex generation by the rod

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Chinese Journal of Aeronautics 2019年第8期32卷 1903-1911页

作者： Ryszard SZWABA Pawel FLASZYNSKI piotr DOERFFER Department of Experimental Aerodynamics Institute of Fluid Flow Machinery Polish Academy of Sciences

The technology development related to aerodynamics is leading to ever increasing loads of wings, airfoils and turbine and compressor blades. The increase in aerodynamic forces is often leading to flow separation and depreciation of the aerodynamic performance of flying objects or propulsion systems. Flow control methods are required to avoid these negative effects. In the recent two decades the flow control by means of air-jet vortex generators has been also intensively investigated. In this method a streamwise vortex is introduced by an oblique jet. The necessity to supply air by a pipe system may be considered a disadvantage. In order to eliminate this feature, it has been proposed to put out a rod instead of a jet. It has been shown that the application of a rod can introduce the same effect as a jet, as long as the streamwise vortex generation is concerned and appropriate dimensions are used. The present paper focuses on the influence of rod vortex generators on a flow pattern downstream. The results presented here concern experimental and numerical investigations and provide guidelines for the design of a new flow control method dedicated mainly to external flows.

关键词： Air-jet vortex generator Boundary layer Flow control Rod vortex generator Streamwise vortices

Odd-even effects in the structure and properties of aryl-substituted aliphatic self-assembled monolayers

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Nano Research 2024年第5期17卷 4231-4243页

作者： piotr Cyganik Andreas Terfort Michael Zharnikov Jagiellonian University Faculty of PhysicsAstronomy and Applied Computer ScienceSmoluchowski Institute of PhysicsŁojasiewicza 1130-348 KrakówPoland Institut für Anorganische und Analytische Chemie Universität FrankfurtMax-von-Laue-Straße 760438 FrankfurtGermany Applied Physical Chemistry Heidelberg UniversityIm Neuenheimer Feld 25369120 HeidelbergGermany

Self-assembled monolayers(SAMs)represent an important tool in context of nanofabrication and molecular engineering of surfaces and *** properties of functional SAMs depend not only on the character of the tail groups at the SAM-ambient interface,but are also largely defined by their *** its turn,the latter parameter results from a complex interplay of the structural forces and a variety of other factors,including so called odd-even effects,*** of the SAM structure and properties on the parity of the number(odd or even)of individual building blocks in the backbone of the SAM *** most impressive manifestation of the odd-even effects is the structure of aryl-substituted alkanethiolate SAMs on Au(111)and Ag(111),in which,in spite of the fact that the intermolecular interaction is mostly determined by the aryl part of the monolayers,one observes a pronounced dependence of molecular inclination and,consequently,the packing density of the SAM-forming molecules on the parity of number of methylene units in the alkyl *** we review the properties of the above systems as well as address fundamental reasons behind the odd-even effects,including the existence of a so-called bending potential,which is frequently disregarded in analysis of the structure-building *** generality of the odd-even effects in SAMs is additionally supported by the recent data for SAMs on GaAs,scanning tunneling microscopy data for SAMs on Ag(111),and the data for the monolayers with selenolate and carboxyl anchoring groups on Au(111)and Ag(111).The implications of these effects in terms of the control over the packing density and orientation of the tail groups at the SAM-ambient interface,structural perfection,polymorphism,temperature-driven phase transitions,and SAM stability toward such factors as ionizing radiation,exchange reaction,and electrochemical desorption are *** implications place the odd-even effects as an important tool

关键词： self-assembled monolayers molecular films surface and interface engineering odd-even-effects