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Geometrical Evaluation of Cervical Cells. Fractal and Euclidean Diagnostic Methodology of Clinical Application

Journal of Biosciences and Medicines 2018年第3期6卷 111-122页

作者： Javier Rodriguez Velasquez Miguel Sanchez Cardenas freddy Andres Barrios Arroyave Yolanda Soracipa munoz Insight Group Research Center of the Clinica del CountryBogotaColombia Research and Social Projection.the Health Sexual and Reproductive Research GroupUniversidad el BosqueBogotaColombia Sexual and Reproductive Health Universidad el Bosque BogotaColombia Epidemiology and Biostatistics CES UniversityMedellinColombia Epidemiology and Biostatistics Research Group CES University and GISCO(Health and Community Research Group)Fundacion Universitaria Autonoma de las AmericasPereiraColombia

Background: The concomitant use of fractal and Euclidian measurements has led to the development of new methodologies of cell evaluation, including a diagnosis of cervical cells that set up differences between normality and various degrees of lesion, to carcinoma. Aim: To confirm the diagnostic capacity of the methodology based on fractal and Euclidian geometry for the mathematical diagnosis through a blind study of normal cells and with different types of lesion, as atypia of undetermined significance (ASCUS), low grade squamous intra-epithelial lesion (LGSIL) and high grade squamous intra-epithelial lesion (HGSIL). Methods: 100 cells of Papanicolaou tests were analyzed and divided into 4 groups according to conventional parameters: 25 normal, 25 ASCUS, 25 LGSIL and 25 HGSIL. By means of the Box-counting Fractal Space, we calculated the fractal dimension and occupying spaces of the border and surface in pixels of the cell nucleus and cytoplasm. The diagnostic parameters of the previously developed methodology were applied and compared with the conventional diagnosis, setting up sensibility, specificity, negative likelihood ratio and Kappa coefficient. Results: The values of the occupation of the border and surface of the cell nucleus and cytoplasm were consistent with the values found by the diagnostic methodology previously found. The subtraction of the nucleus and cytoplasm frontiers presented values between: 189 and 482 for normality;159 and 432 for ASCUS;126 to 401 for LGSIL and 39 to 122 for HGSIL. A sensitivity and specificity of 100%, and a Kappa coefficient of 1 were obtained. Conclusions: The capacity of the methodology to diagnose quantitatively the different stages in the evolution of the cervical cells observed in Papanicolaou tests was confirmed, from normality to HGSIL.

关键词： Fractals Cervical Cancer Cytology Mathematics

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Understanding and tuning blue-to-near-infrared photon cutting by the Tm^(3+)/Yb^(3+) couple

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Light(Science & Applications) 2020年第1期9卷 992-1000页

作者： Dechao Yu Ting Yu Arnoldus Jvan Bunningen Qinyuan Zhang Andries Meijerink freddy T.Rabouw Debye Institute for Nanomaterials Science Utrecht UniversityPrincetonplein 13584 CC UtrechtThe Netherlands State Key Laboratory of Luminescence Materials and Devices Institute of Optical Communication MaterialsSouth China University of TechnologyGuangzhou 510641China

Lanthanide-based photon-cutting phosphors absorb high-energy photons and‘cut’them into multiple smaller excitation *** quanta are subsequently emitted,resulting in photon-conversion efficiencies exceeding *** photon-cutting process relies on energy transfer between optically active lanthanide ions doped in the ***,it is not always easy to determine,let alone predict,which energy-transfer mechanisms are operative in a particular *** makes the identification and design of new promising photon-cutting phosphors *** we unravel the possibility of using the Tm^(3+)/Yb^(3+) lanthanide couple for photon *** compare the performance of this couple in four different host *** energy transfer from Tm^(3+)to Yb^(3+) would enable blue-to-near-infrared conversion with 200% ***,we identify phonon-assisted cross-relaxation as the dominant Tm^(3+)-to-Yb^(3+) energy-transfer mechanism in YBO_(3),YAG,and Y_(2)O_(3).In NaYF_(4),in contrast,the low maximum phonon energy renders phonon-assisted cross-relaxation impossible,making the desired cooperative mechanism the dominant energy-transfer *** work demonstrates that previous claims of high photon-cutting efficiencies obtained with the Tm^(3+)/Yb^(3+) couple must be interpreted with ***,the Tm^(3+)/Yb^(3+) couple is potentially promising,but the host material-more specifically,its maximum phonon energy-has a critical effect on the energy-transfer mechanisms and thereby on the photon-cutting performance.

关键词： couple phonon lanthanide

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Multi-photon quantum cutting in Gd_(2)O_(2)S:Tm^(3+) to enhance the photo-response of solar cells

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Light(Science & Applications) 2015年第1期4卷 144-151页

作者： De-Chao Yu Rosa Martin-Rodriguez Qin-Yuan Zhang Andries Meijerink freddy T Rabouw State Key Laboratory of Luminescence Materials and Devices and Institute of Optical Communication Materials South China University of TechnologyGuangzhou 510641China Debye Institute for Nanomaterials Science Utrecht UniversityP.O.Box 800003508 TA Utrechtthe Netherlands

Conventional photoluminescence(PL)yields at most one emitted photon for each absorption ***(or quantum cutting)materials can yield more than one photon by virtue of energy transfer processes between luminescent *** this work,we introduce Gd2O2S:Tm^(3+) as a multi-photon quantum *** can convert near-infrared,visible,or ultraviolet photons into two,three,or four infrared photons of,1800 nm,*** cross-relaxation steps between Tm^(3+) ions that lead to quantum cutting are identified from(time-resolved)PL as a function of the Tm^(3+) concentration in the crystal.A model is presented that reproduces the way in which the Tm^(3+) concentration affects both the relative intensities of the various emission lines and the excited state dynamics and providing insight in the quantum cutting ***,we discuss the potential application of Gd2O2S:Tm^(3+) for spectral conversion to improve the efficiency of next-generation photovoltaics.

关键词： downconversion infrared emission quantum cutting solar cells spectral conversions

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Pore structure effects on the kinetics of methanol oxidation over nanocast mesoporous perovskites

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Chinese Journal of Catalysis 2016年第1期37卷 32-42页

作者： Mahesh M.Nair freddy Kleitz Serge Kaliaguine 拉瓦尔大学化学Materiaux Avances研究中心(CERMA) 加拿大魁北克G1V 0A6 拉瓦尔大学化工系加拿大魁北克G1V 0A6

Mesoporous LaMnO3 perovskite catalysts with high surface area were synthesized by using the recently developed hard templating method designated as ＂nanocasting＂.Ordered mesoporous silica designated as SBA-15 was used as the hard *** was found that the surface area of the nanocast perovskites can be tuned（80–190 m2/g）by varying the aging temperature of the SBA-15 *** LaMnO3 catalysts showed high conversion efficiencies for the total oxidation of methanol under steady state conditions,the one with the highest value of surface area being the best catalysts,as *** studies were performed for all of the synthesized *** constants were found to vary in accordance with the specific surface area of the nanocast catalyst which depends on the aging temperature of the parent *** the rate constants obtained from experimental conversions at various space velocities（19500 to 78200 h〈sup〉–1）,values of activation energy and pre-exponential factor for the three nanocast LaMnO3 catalysts were determined by the linear regression of the Arrhenius *** is observed that the activation energy for all the catalysts remain constant irrespective of the variation in specific surface ***,a linear relationship was found to exist between the pre-exponential factor and specific surface areas of the catalysts indicating that the rates per unit surface area remains the same for all the catalysts.

关键词： Mesoporous perovskites High surface area Nanocasting Methanol oxidation Kinetics

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Effects of "Candidatus Liberibacter solanacearum"(haplotype B)on Bactericera cockerelli fitness and vitellogenesis

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Insect Science 2020年第1期27卷 58-68页

作者： Angelica Albuquerque Tomilhero Frias freddy Ibanez Azucena Mendoza William Mario de Carvalho Nunes Cecilia Tamborindeguy Department of Entomology Texas A&M University412 Heep CenterCollege StationTexasUSA DEM-Depto.de Agronomia Nucleo de Pesquisa em Biotecnologia AplicadaMaringaBrazil

"Candidatus Liberibacter solanacearum"(Lso)are phloem-restricted and unculturable Gram-negative *** five haplotypes have been identified worldwide;but only haplotypes A and B are associated with the vector Bactericera cockerelli(Sulc.)in the *** studies showed that Lso-infection reduces *** reproductive output and that Lso haplotype B is more pathogenic than Lso haplotype *** understand the interaction of Lso haplotype B and ***,the fitness of Lso-free and Lso B-infected insects,and the expression of vitellogenin(5cKg7-like),a gene involved directly in the insect reproduction were *** differences in the number of eggs oviposited,and the total number of progeny nymphs and adults were found among crosses of insects with or without *** differences in sex proportions were found between Lso B-infected and Lso-free crosses:a higher proportion of Fi adult females were obtained from Lso B-infected mothers.A significant reduction of BcVgl-like was observed in crosses performed with Lso B-infected females compared to the Lso-free *** female cohorts of different age,a significant reduction of BcVgl-like expression was measured in 7-d-old Lso B-infected females(virgin and mated)compared with 7-d-old Lso-free females(virgin and mated),*** reduction of BcVgl-like transcript was associated with a lower number of developing oocytes observed in female5s reproductive ***,this study represents the first step to understand the interaction of Lso B with ***,highlighting the effect of Lso B infection on egg production,BcVgl-like expression,and oocyte development.

关键词： feminization insect-pathogen interaction oviposition psyllids reproduction vitellogenesis

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Extending the dynamic temperature range of Boltzmann thermometers

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Light(Science & Applications) 2022年第12期11卷 3069-3079页

作者： Thomas Pieter van Swieten Jesse Merlijin Steenhoff Auke Vlasblom Ravi de Berg Sam Pieter Mattern freddy Teunis Rabouw Markus Suta Andries Meijerink Debye Institute for Nanomaterials Science Utrecht UniversityPrincetonplein 13584 CC UtrechtThe Netherlands Inorganic Photoactive Materials Heinrich Heine University DüsseldorfUniversitätsstraBe 140225 DüsseldorfGermany

Lanthanide-doped(nano)crystals are an important class of materials in luminescence *** working mechanism of these thermometers is diverse but most often relies on variation of the ratio of emission intensities from two thermally coupled excited states with *** low temperatures,nonradiative coupling between the states can be slow compared to radiative decay,but,at higher temperatures,the two states reach thermal equilibrium due to faster nonradiative *** thermal equilibrium,the intensity ratio follows Boltzmann statistics,which gives a convenient model to calibrate the ***,we investigate multiple strategies to shift the onset of thermal equilibrium to lower temperatures,which enables Boltzmann thermometry in a wider dynamic *** use Eu^(3+)-doped microcrystals as a model system and find that the nonradiative coupling rates increase for host lattices with higher vibrational energies and shorter lanthanide-ligand distances,which reduces the onset temperature of thermal equilibrium by more than 400 *** additionally reveal that thermometers with excited states coupled by electricdipole transitions have lower onset temperatures than those with magnetic-dipole-coupled states due to selection *** insights provide essential guidelines for the optimization of Boltzmann thermometers to operate in an extended temperature range.

关键词： equilibrium excited dynamic

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《冷山》的象征主义及其他

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电影文学 2005年第12期 62-63页

作者： freddy

听说电影《冷山》之后,才知道有小说。断断续续地读完,更增添了对电影的预期。而后终在银幕上看到了明格拉的影片。走出影院之后,有一个镜头却始终缠绕着我的思绪,不禁要对电影和小说作一番深入细致的比较。在黑暗的影院内,电影镜头开... 详细信息

听说电影《冷山》之后,才知道有小说。断断续续地读完,更增添了对电影的预期。而后终在银幕上看到了明格拉的影片。走出影院之后,有一个镜头却始终缠绕着我的思绪,不禁要对电影和小说作一番深入细致的比较。在黑暗的影院内,电影镜头开始慢慢慢慢地,然后一点一点地逐渐加速,围绕着一个垂死的士兵旋转。英曼开始咳嗽。

关键词：象征主义手法小说电影乌鸡深入细致影片士兵镜头观众莎拉

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Physicochemical Properties of Combustion Ashes of Some Trees(Urban Pruning)Present in the Neotropical Region

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Journal of Renewable Materials 2023年第10期11卷 3769-3787页

作者： John freddy Gelves-Díaz Ludovic Dorkis Richard Monroy-Sepúlveda Sandra Rozo-Rincón Yebrail Alexis Romero-Arcos Competitiveness and Sustainability for Development Research Group Faculty of EngineeringUniversidad Libre-Cúcuta SectionalCúcutaColombia Catalysis and Nanomaterials Research Group Faculty of MinesUniversidad Nacional de Colombia-Medellín SectionalMedellínColombia

Secondary lignocellulosic biomass has proved to be useful as an energy source through its oxidation by means of combustion *** accordance with the above,in this paper,we wanted to study the ash from urban pruning residues that are generated in cities in the *** such as Licania tomentosa,Azadirachta indica,Ficus benjamina,Terminalia catappa,Leucaena leucocephala,Prosopis juliflora and Pithecellobium dulce were selected because they have been previously studied and showed potential for thermal energy *** materials were calcined in an oxidizing atmosphere and characterized by X-ray diffraction and fluorescence,scanning electron microscopy with microchemistry,BET surface area,thermal gravimetric analysis,and differential scanning *** pH and apparent density were also *** results show high basicity materials(average pH 10),a behavior associated with the presence of chemical elements such as calcium,potassium,magnesium,chlorine,phosphorus,and ***,these materials have a very significant amorphous fraction(between 49%and 74.5%),the dominant crystalline phases are calcite,arcanite,sylvite,and *** ashes have low surface area and do not exceed 13 m^(2)/*** characteristic morphological aspects were observed in these ashes:a morphology of rounded grains where silicon content is highlighted,and lamellar morphologies where the presence of chlorine is ***,these ashes show four significant mass loss events(400℃,430℃,680℃,and 920℃),causing mass losses that vary between 25%and 40%.Through this study,it was possible to establish that,from a chemical point of view,these ashes are less dangerous in comparison with those of a mineral coal that was used as a ***,they require additional treatments for their disposal due to their high *** of their composition,these ashes have the potential to be used in the ceramic and cement industries,and in the manuf

关键词： Bottom ash chemical composition characterization mineralogy plant biomass pruning residues urban flora

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A Primer for Mapping Techniques on NoC Systems

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通讯和计算机（中英文版） 2014年第4期11卷 333-338页

作者： Maribell Sacanamboy freddy Bolanos Ruben Nieto Department of Electronics and Computer Sciences Pontificia Universidad Javeriana Cali Valle del Cauca Colombia Department of Electrical Engineering and Automatics Universidad Nacional de Colombia Medellin Antioquia Colombia School of Electrical and Electronics Engineering Universidad del Valle Cali Valle del Cauca Colombia

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Helicobacter pylori HopE and HopV porins present scarce expression among clinical isolates

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World Journal of Gastroenterology 2010年第3期16卷 320-329页

作者： Maritza Lienlaf Juan Pablo Morales María Inés Díaz Rodrigo Díaz Elsa Bruce freddy Siegel Gloria León Paul R Harris Alejandro Venegas Microbial Pathogenesis and Vaccine Biotechnology Laboratory Department of Molecular Genetics and MicrobiologyFaculty of Biological SciencesPontificia Universidad Católica de Chile Gastroenterology Unit Faculty of MedicineUniversidad Austral de Chile Institute of Biochemistry Faculty of SciencesUniversidad Austral de Chile Department of Pediatrics School of MedicinePontificia Universidad Católica de Chile

AIM:To evaluate how widely Helicobacter pylori (H. pylori ) HopE and HopV porins are expressed among Chilean isolates and how seroprevalent they are among infected patients in ***: H. pylori hopE and hopV genes derived from strain CHCTX-1 were cloned by polymerase chain reaction (PCR), sequenced and expressed in Escherichia coli AD494 (DE3). Gel-purified porins were used to prepare polyclonal antibodies. The presence of both genes was tested by PCR in a collection of H. pylori clinical isolates and their expression was detected in lysates by immunoblotting. Immune responses against HopE, HopV and other H. pylori antigens in sera from infected and non-infected patients were tested by Western blotting using these sera as f irst antibody on recombinant H. pylori ***: PCR and Western blotting assays revealed that 60 and 82 out of 130 Chilean isolates carried hopE and hopV genes, respectively, but only 16 and 9, respectively, expressed these porins. IgG serum immunoreactivity evaluation of 69 H. pylori-infected patients revealed that HopE and HopV were infrequently recognized (8.7% and 10.1% respectively) compared to H. pylori VacA (68.1%) and CagA (59.5%) antigens. Similar values were detected for IgA serum immunoreactivity against HopE (11.6%) and HopV (10.5%) although lower values for VacA (42%) and CagA (17.4%) were obtained when compared to the IgG ***: A scarce expression of HopE and HopV among Chilean isolates was found, in agreement with the infrequent seroconversion against these antigens when tested in infected Chilean patients.

关键词： Helicobacter pylori Gene expression HopE and HopV porins Antigens Immune response

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