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Slow and fast light in quantum-well and quantum-dot semiconductor optical amplifiers Invited Paper

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Chinese Optics Letters 2008年第10期6卷 736-742页

作者： piotr Konrad Kondratko Akira Matsudaira Department of Electrical and Computer Engineering University of Illinois at Urbana-ChampaignUrbana IL61801USA

Slow and fast light in quantum-well （QW） and quantum-dot （QD） semiconductor optical amplifiers （SOAs） using nonlinear quantum optical effects are presented. We demonstrate electrical and optical controls of fast light using the coherent population oscillation （CPO） and four wave mixing （FWM） in the gain regime of QW SOAs. We then consider the dependence on the wavelength and modal gain of the pump in QW SOAs. To enhance the tunable photonic delay of a single QW SOA, we explore a serial cascade of multiple amplifiers. A model for the number of QW SOAs in series with variable optical attenuation is developed and matched to the experimental data. We demonstrate the scaling law and the bandwidth control by using the serial cascade of multiple QW SOAs. Experimentally, we achieve a phase change of 160^o and a scaling factor of four at 1 GHz using the cascade of four QW SOAs. Finally, we investigate CPO and FWM slow and fast light of QD SOAs. The experiment shows that the bandwidth of the time delay as a function of the modulation frequency changes in the absorption and gain regimes due to the carrier-lifetime variation. The tunable phase shift in QD SOA is compared between the ground- and first excited-state transitions with different modal gains.

关键词： SOA CPO Slow and fast light in quantum-well and quantum-dot semiconductor optical amplifiers Invited Paper FWM well

Transposable elements significantly contributed to the core promoters in the human genome

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Science China(Life Sciences) 2019年第4期62卷 489-497页

作者： Marten Kellner wojciech Maka?owski Institute of Bioinformatics Faculty of Medicine University of Münster

Transposable elements(TEs) are major components of the human genome constituting at least half of it. More than half a century ago, Barbara McClintock and later Roy Britten and Eric Davidson have postulated that they might be major players in the host gene regulation. We have scanned a large amount of data produced by ENCODE project for active transcription binding sites(TFBSs) located in TE-originated parts of polymerase II promoters. In total, more than 35,000 promoters in six different tissues were analyzed and over 26,000 of them harbored TEs. Moreover, these TEs usually provide one or more of TFBSs in the host promoters, which resulted in more than 6% of active TFBSs in these regions located in the TE-originated sequences. Rewiring of transcription circuits played a major role in mammalian evolution and consequently increased their functional and morphological diversity. In this large-scale analysis, we have demonstrated that TEs contributed a large fraction of human TFBSs. Interestingly,these TFBSs usually act in a tissue-specific manner. Thus, our study clearly showed that TEs played a significant role in shaping expression pattern in mammals and humans in particular. Furthermore, since several TE families are still active in our genome,they continue to influence not only our genome architecture but also gene functioning in a broader sense.

关键词： transposable elements genome evolution gene expression evolution transcription factors transcription binding sites,ENCODE project promoters

Generalized stiffness and effective mass coefficients for power-law Euler-Bernoulli beams

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Acta Mechanica Sinica 2020年第1期36卷 160-175页

作者： piotr Skrzypacz Daulet Nurakhmetov Dongming Wei School of Sciences and Humanities Nazarbayev University010000Nur-SultanKazakhstan

We extend the well-known concept and results for lumped parameters used in the spring-like models for linear materials to Hollomon’s power-law *** provide the generalized stiffness and effective mass coefficients for the power-law Euler-Bernoulli beams under standard geometric and load *** particular,our mass-spring lumped parameter models reduce to the classical models when Hollomon’s law reduces to Hooke’s *** there are no known solutions to the dynamic power-law beam equations,solutions to our mass lumped models are compared to the low-order Galerkin approximations in the case of cantilever beams with circular and rectangular cross-sections.

关键词： Power-law Euler-Bernoulli beams Lumped parameter models Generalized stiffness coefficient Effective mass coefficient

In elderly population prophylactic anticoagulation favors early detection of digestive track cancers: an observational study in eastern Poland

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Journal of Geriatric Cardiology 2019年第6期16卷 495-497页

作者： Malgorzata Szlendak wojciech Myslinski Jerzy Mosiewicz wojciech Barud Department of Internal Diseases Medical University in Lublin Poland Human Anatomy Department Medical University in Lublin Poland

The launch of non-VKA oral anticoagulants (NOACs) caused revolution in thrombosis prevention, which was mainly due to their safety and simplicity in treatment when compared to vitamin K antagonists (VKA). Clinical observations indicate that despite the benefits of NOACs, many patients still use VKA even if they cannot cope with dose modifications and often do not control INR.

关键词： Anticoagulants Colonic neoplasms Gastrointestinal hemorrhage

Changes in the speed of ants as a result of aggressive interactions

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Insect Science 2017年第5期24卷 842-852页

作者： piotr Slipinski Michal Zmihorski Laboratory of Social and Myrmecophilous Insects Museum and Institute of Zoology Polish Academy of Sciences Warsaw Poland Department of Ecology Swedish University of Agricultural Sciences Uppsala Sweden Institute of Nature Conservation PolishAcademy of Sciences Krakow Poland

Subordinate ant species utilize different tactics to reduce competition with the stronger, larger and more aggressive individuals of a dominant species. In our experimental study, we assessed the behavioral response of individual workers of 4 subordinate ant species during their co-occurrence with workers of a single dominant species. Contrary to most classical experiments focused on aggressive interactions, we assessed workers＇ speed as a crucial factor in the outcome of co-occurrence. Generally, there was a large intraspecific variation in the speed of the studied species--each had slow and fast individuals. Workers of all studied species moved faster just after interaction, suggesting that contact between 2 hostile workers is a stressful stimulus, generating a behavioral reaction of increasing speed. Also, the number of aggressive contacts experienced by a given individual positively affected its speed. Moreover, workers which were fast when exploring territory were also fast after interspecific interactions. The duration of aggression was significantly reduced by the speed and body size of a subordinate species worker--the more quickly a worker reacted and bigger it was, the shorter was the time of cumulative aggression. To our knowledge, this is the first study of this type to be conducted on ants and we conclude that speed is an overlooked and important characteristic of species and also individuals, therefore it should be considered as a driver of patterns of co-occurrence in ant assemblages.

关键词： hierarchy reaction response speed survival velocity

Prognostic value of metabolic tumor burden in lung cancer

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Chinese Journal of Cancer Research 2013年第6期25卷 615-622页

作者： piotr Obara Yonglin Pu Department of Radiology University of Chicago

Accurate prognosis in patients with lung cancer is important for clinical decision making and treatment selection. The TNM staging system is currently the main method for establishing prognosis. Using this system, patients are grouped into one of four stages based on primary tumor extent, nodal disease, and distant metastases. However, each stage represents a range of disease extent and may not on its own be the best reflection of individual patient prognosis. 18F-fluorodeoxyglucose_positron emission tomography （18F-FDG-PET） can be used to evaluate the metabolic tumor burden affecting the whole body with measures such as metabolic rumor volume （MTV） and total lesion glycolysis （TLG）. MTV and TLG have been shown to be significant prognostic factors in patients with lung cancer, independent of TNM stage. These metabolic tumor burden measures have the potential to make lung cancer staging and prognostication more accurate and quantitative, with the goal of optimizing treatment choices and outcome predictions.

关键词： Lung cancer 18F-fluorodeoxyglucose-positron emission tomography 18F-FDG-PET) prognosticfactors metabolic tumor volume (MTV) total lesion glycolysis (TLG)

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

Cadmium and lead toxicity and bioaccumulation in Microcystis aeruginosa

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Frontiers of Environmental Science & Engineering 2014年第3期8卷 427-432页

作者： piotr RZYMSKI Barbara PONIEDZIALEK Przemyslaw NIEDZIELSKI piotr TABACZEWSKI Krzysztof WIKTOROWICZ Department of Biology and Environmental Protection Poznan University of Medical Sciences Poznan 61-848 Poland Faculty of Chemistry Department of Water and Soil Analysis Adam Mickiewicz University Poznan 61-614 Poland

The growth of human population leads to intensification of agriculture and promotes, through eutrophication, development of cyanobacteria. One of the most widespread and bloom-forming species in freshwater is toxic Microcystis aeruginosa （M. aeruginosa）. Combustion of fossil fuels and metallurgical processes are the main sources of heavy metals contamination in surface water including cadmium （Cd） and lead （Pb）. The following study was conducted in order to determine the effect of 1- 20 mg. L-1 of Cd and Pb on photochemistry （using flow cytometry） and growth （based on chlorophyll concentra- tion） ofM. aeruginosa as well as to estimate levels of metal bioaccumulation. We have found that 1-10mg.L-1 of Cd and 1-5 rag. L1 of Pb induced continuous enhancement of chlorophyll fluorescence during 24 h of incubation. No significant degradation of chlorophyll was observed in these samples. At higher concentrations of 20 mg. L-1 of Cd and 10-20 mg.L-1 of Pb chlorophyll level significantly decreased and its fluorescence was quenched. M. aeruginosa demonstrated high capability of Cd and Pb bioaccumulation, proportionally to initial metal concentration. In samples with initial concentration of 20 mg. L-1 of Cd and Pb bioaccumulation of 87.3% and 90.1% was observed, respectively. Our study demonstrates that M. aeruginosa can potentially survive in highly metals polluted environments, be a primary source of toxic metals in the food chain and consequently contribute to enhanced toxicity of heavy metals to living organisms including human.

关键词： Microcystis aeruginosa heavy metals bioac-cumulation chlorophyll flow cytometry

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