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Journal articles on the topic 'MQP'
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Liu, Shi-Feng, Corey Seward, Hany Aziz, Nan-Xing Hu, Zoran Popović, and Suning Wang. "Syntheses, Structures, and Luminescence/Electroluminescence of BPh2(mqp), Al(CH3)(mqp)2, and Al(mqp)3(mqp = 2-(4‘-Methylquinolinyl)-2-phenolato)." Organometallics 19, no. 26 (2000): 5709–14. http://dx.doi.org/10.1021/om0006918.
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Frausto-Solis, Juan, Ernesto Liñan-García, Mishael Sánchez-Pérez, and Juan Paulo Sánchez-Hernández. "Chaotic Multiquenching Annealing Applied to the Protein Folding Problem." Scientific World Journal 2014 (2014): 1–11. http://dx.doi.org/10.1155/2014/364352.
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The Chaotic Multiquenching Annealing algorithm (CMQA) is proposed. CMQA is a new algorithm, which is applied to protein folding problem (PFP). This algorithm is divided into three phases: (i) multiquenching phase (MQP), (ii) annealing phase (AP), and (iii) dynamical equilibrium phase (DEP). MQP enforces several stages of quick quenching processes that include chaotic functions. The chaotic functions can increase the exploration potential of solutions space of PFP. AP phase implements a simulated annealing algorithm (SA) with an exponential cooling function. MQP and AP are delimited by different ranges of temperatures; MQP is applied for a range of temperatures which goes from extremely high values to very high values; AP searches for solutions in a range of temperatures from high values to extremely low values. DEP phase finds the equilibrium in a dynamic way by applying least squares method. CMQA is tested with several instances of PFP.
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Baques, D. Bueno, D. R. Cornejo, E. Padron Hernandez, P. Sifuentes Gallardo, O. Rodriguez Fernandez, and J. A. Matutes Aquino. "Sr ferrite-MQP hybrid bonded magnets." International Journal of Materials and Product Technology 27, no. 1/2 (2006): 71. http://dx.doi.org/10.1504/ijmpt.2006.010671.
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Neznakhin, Dmitriy Sergeevich, Galina Aleksandrovna Politova, Lev Aleksandrovich Ivanov, et al. "Low-Temperature Magnetic Hysteresis in Nd(Pr)-Fe-B Nanostructured Alloys with Nd2Fe14B Type Main Phase Composition." Defect and Diffusion Forum 386 (September 2018): 125–30. http://dx.doi.org/10.4028/www.scientific.net/ddf.386.125.
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Magnetic hysteresis properties of nanostructured industrially manufactured Nd-Fe-B and Pr-Fe-B alloys on the base of a tetragonal Nd2Fe14B (2-14-1) hard magnetic phase (MQP-B, MQP-B+ and MQP-16-7 brands) have been investigated at 4.2 K in magnetic fields up to 58 T. The chemical composition of the alloys given in the certificates was defined more precisely. The grain sizes of the main 2-14-1 phase were determined. The average grain size is much smaller than a critical single domain diameter. Coercivity, remanence magnetization, saturation magnetization and maximal magnetic energy product were determined at 4.2 K and compared with those obtained at room temperature.
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Kudrevatykh, Nikolai V., A. S. Volegov, A. V. Glebov, et al. "Microstructure and Magnetic Hysteresis in Nanocrystalline Nd-Fe-Co-B Alloys on the Base of Nd2Fe14B Phase." Solid State Phenomena 168-169 (December 2010): 420–23. http://dx.doi.org/10.4028/www.scientific.net/ssp.168-169.420.
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Using the electron microscopy (SEM and TEM), X-ray structure analysis and precise magnetometry methods (VSM, SQUID-magnetometer), the microstructure and magnetic hysteresis properties of industrial manufactured hard magnetic rare-earth based alloys of Nd-Fe-Co-B compositions (BZMP and MQP-B brands) that are widely applied as fillers for bonded magnets (magnetoplasts and magnetoelasts) have been studied. The obtained results allow selecting the proper temperature range for bonded magnets applications on the base of BZMP and MQP-B fillers.
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Oates, Martin J., Nawaf Abu-Khalaf, Carlos Molina-Cabrera, Antonio Ruiz-Canales, Jose Ramos, and Brian W. Bahder. "Detection of Lethal Bronzing Disease in Cabbage Palms (Sabal palmetto) Using a Low-Cost Electronic Nose." Biosensors 10, no. 11 (2020): 188. http://dx.doi.org/10.3390/bios10110188.
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Lethal Bronzing Disease (LB) is a disease of palms caused by the 16SrIV-D phytoplasma. A low-cost electronic nose (eNose) prototype was trialed for its detection. It includes an array of eight Taguchi-type (MQ) sensors (MQ135, MQ2, MQ3, MQ4, MQ5, MQ9, MQ7, and MQ8) controlled by an Arduino NANO® microcontroller, using heater voltages that vary sinusoidally over a 2.5 min cycle. Samples of uninfected, early symptomatic, moderate symptomatic, and late symptomatic infected palm leaves of the cabbage palm were processed and analyzed. MQ sensor responses were subjected to a 256 element discrete Fourier transform (DFT), and harmonic component amplitudes were reviewed by principal component analysis (PCA). The experiment was repeated three times, each showing clear evidence of differences in sensor responses between the samples of uninfected leaves and those in the early stages of infection. Within each experiment, four groups of responses were identified, demonstrating the ability of the unit to repeatedly distinguish healthy leaves from diseased ones; however, detection of the severity of infection has not been demonstrated. By selecting appropriate coefficients (here demonstrated with plots of MQ5 Cos1 vs. MQ8 Sin3), it should be possible to build a ruleset classifier to identify healthy and unhealthy samples.
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Ávila, Léo F., Carlos R. de Mello, and Marcelo R. Viola. "Mapeamento da precipitação mínima provável para o sul de Minas Gerais." Revista Brasileira de Engenharia Agrícola e Ambiental 13, suppl (2009): 906–15. http://dx.doi.org/10.1590/s1415-43662009000700013.
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O mapeamento da precipitação mínima provável associada a um período, local e freqüência de ocorrência, consiste em importante ferramenta para subsídios de práticas agrícolas. O objetivo neste trabalho foi mapear a precipitação provável mínima mensal e quinzenal para o Sul do Estado de Minas Gerais, por meio de técnicas geoestatísticas. O nível de probabilidade considerado foi de 75% e o período analisado foi a estação chuvosa (outubro a março). Os valores de precipitação provável foram estimados pela distribuição de probabilidade Log-Normal, após teste de sua adequação, por Kolmogorov-Smirnov, a partir de séries históricas de dados totais diários de precipitação referentes a 69 estações pluviométricas da região e arredores. Os modelos de semivariograma exponencial e esférico ajustados pela máxima verossimilhança (MV) e por mínimos quadrados ponderados (MQP) foram modelados para a escolha do melhor modelo que representasse o semivariograma experimental. Com base no grau de dependência espacial e pela validação cruzada, o modelo exponencial ajustado por MQP apresentou melhor desempenho. Os mapas de precipitação provável mostraram considerável variabilidade durante a estação chuvosa, com os maiores valores estimados para as regiões das Serras da Mantiqueira e Canastra.
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Iqbal, Naeem, Rashid Ahmad, Faisal Jamil, and Do-Hyeun Kim. "Hybrid features prediction model of movie quality using Multi-machine learning techniques for effective business resource planning." Journal of Intelligent & Fuzzy Systems 40, no. 5 (2021): 9361–82. http://dx.doi.org/10.3233/jifs-201844.
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Quality prediction plays an essential role in the business outcome of the product. Due to the business interest of the concept, it has extensively been studied in the last few years. Advancement in machine learning (ML) techniques and with the advent of robust and sophisticated ML algorithms, it is required to analyze the factors influencing the success of the movies. This paper presents a hybrid features prediction model based on pre-released and social media data features using multiple ML techniques to predict the quality of the pre-released movies for effective business resource planning. This study aims to integrate pre-released and social media data features to form a hybrid features-based movie quality prediction (MQP) model. The proposed model comprises of two different experimental models; (i) predict movies quality using the original set of features and (ii) develop a subset of features based on principle component analysis technique to predict movies success class. This work employ and implement different ML-based classification models, such as Decision Tree (DT), Support Vector Machines with the linear and quadratic kernel (L-SVM and Q-SVM), Logistic Regression (LR), Bagged Tree (BT) and Boosted Tree (BOT), to predict the quality of the movies. Different performance measures are utilized to evaluate the performance of the proposed ML-based classification models, such as Accuracy (AC), Precision (PR), Recall (RE), and F-Measure (FM). The experimental results reveal that BT and BOT classifiers performed accurately and produced high accuracy compared to other classifiers, such as DT, LR, LSVM, and Q-SVM. The BT and BOT classifiers achieved an accuracy of 90.1% and 89.7%, which shows an efficiency of the proposed MQP model compared to other state-of-art- techniques. The proposed work is also compared with existing prediction models, and experimental results indicate that the proposed MQP model performed slightly better compared to other models. The experimental results will help the movies industry to formulate business resources effectively, such as investment, number of screens, and release date planning, etc.
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Mello, Carlos Rogério de, Marcelo Ribeiro Viola, José Marcio de Mello, and Antônio Marciano da Silva. "Continuidade espacial de chuvas intensas no estado de Minas Gerais." Ciência e Agrotecnologia 32, no. 2 (2008): 532–39. http://dx.doi.org/10.1590/s1413-70542008000200029.
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O mapeamento de variáveis climáticas, como chuvas intensas, é de fundamental importância para o manejo ambiental. Para isto, ferramentas estatísticas para interpolação espacial devem ser devidamente analisadas e caracterizadas. Assim, objetivou-se com este trabalho analisar modelos e métodos de modelagem do semivariograma que melhor se ajustem a chuvas intensas com duração de 20, 60, 360 e 1440 minutos e tempos de retorno de 5, 50 e 100 anos, fornecendo subsídios primordiais para espacialização da mesma pelo interpolador geoestatístico, para o Estado de Minas Gerais. Foram testados os modelos esférico, exponencial e gaussiano pelos métodos de ajuste da Máxima Verossimilhança (MV) e Mínimos Quadrados Ponderados (MQP). Utilizou-se como critério de escolha do melhor modelo, o menor erro médio gerado pela validação cruzada, e em caso de similaridade, também foram considerados o maior grau de dependência espacial e o menor efeito pepita, além da análise visual do ajuste do modelo ao semivariograma experimental. O modelo exponencial se sobressaiu em nove das doze situações analisadas, o gaussiano em duas e o esférico em uma situação. Quanto aos métodos de ajuste, o MQP sobressaiu em todos os casos estudados, o que permite sugerir o modelo exponencial ajustado pelo método dos mínimos quadrados ponderados como sendo o mais adequado para o mapeamento da chuva intensa para as condições do Estado de Minas Gerais.
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Frausto-Solis, Juan, Ernesto Liñán-García, Juan Paulo Sánchez-Hernández, J. Javier González-Barbosa, Carlos González-Flores, and Guadalupe Castilla-Valdez. "Multiphase Simulated Annealing Based on Boltzmann and Bose-Einstein Distribution Applied to Protein Folding Problem." Advances in Bioinformatics 2016 (June 20, 2016): 1–16. http://dx.doi.org/10.1155/2016/7357123.
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A new hybrid Multiphase Simulated Annealing Algorithm using Boltzmann and Bose-Einstein distributions (MPSABBE) is proposed. MPSABBE was designed for solving the Protein Folding Problem (PFP) instances. This new approach has four phases: (i) Multiquenching Phase (MQP), (ii) Boltzmann Annealing Phase (BAP), (iii) Bose-Einstein Annealing Phase (BEAP), and (iv) Dynamical Equilibrium Phase (DEP). BAP and BEAP are simulated annealing searching procedures based on Boltzmann and Bose-Einstein distributions, respectively. DEP is also a simulated annealing search procedure, which is applied at the final temperature of the fourth phase, which can be seen as a second Bose-Einstein phase. MQP is a search process that ranges from extremely high to high temperatures, applying a very fast cooling process, and is not very restrictive to accept new solutions. However, BAP and BEAP range from high to low and from low to very low temperatures, respectively. They are more restrictive for accepting new solutions. DEP uses a particular heuristic to detect the stochastic equilibrium by applying a least squares method during its execution. MPSABBE parameters are tuned with an analytical method, which considers the maximal and minimal deterioration of problem instances. MPSABBE was tested with several instances of PFP, showing that the use of both distributions is better than using only the Boltzmann distribution on the classical SA.
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Kapelski, D., B. Jankowski, M. Przybylski, and B. Ślusarek. "The Influence Of The Temperature Of Liquid Nitrogen On The Physical Properties Of Powder Magnetic Composites." Archives of Metallurgy and Materials 60, no. 2 (2015): 1323–26. http://dx.doi.org/10.1515/amm-2015-0123.
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Abstract The paper presents the physical properties of soft magnetic iron composites and Nd-Fe-B bonded permanent magnets measured at room temperature and at liquid nitrogen. The objective of research was a determination of influence of liquid nitrogen temperature on the magnetic properties, resistivity and mechanical properties of different powder magnetic materials. Research was carried out for three powder materials: soft magnetic, i.e. Somaloy 700, AncorLam and hard magnetic powder MQP-B used for production of bonded magnets. Composite specimens were prepared by compression moulding technology.
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Qin, Wan Zhong, and Jie He. "Research on Bonded NdFeB Arc-Magnets." Advanced Materials Research 941-944 (June 2014): 614–18. http://dx.doi.org/10.4028/www.scientific.net/amr.941-944.614.
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The manufacture technology and mould structure of bonded NdFeB arc-magnets from press molding were described. The effects of the content of binder and additives, particle size of magnetic powder, the molding pressure, the treatment of magnet surface on the mechanical property, processing property, magnetic property and anti-oxidation property of press molding magnets were investigated. The press molding bonded magnets were prepared by using the MQP-B rapidly quenching NdFeB magnetic powder and epoxy binder. The magnetic properties are: Br = 0.722 T, Hcb = 457 kA/m, Hci = 718 kA/m, and (BH) max = 83.5 kJ/m3.
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Qin, Wan Zhong, Jie He, and Jia Hong Meng. "Research on Composite Powder and Magnet Properties of Bonded NdFeB Magnets." Advanced Materials Research 535-537 (June 2012): 1314–18. http://dx.doi.org/10.4028/www.scientific.net/amr.535-537.1314.
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The injection molding of magnetic powder could cost-effectively mass-produce net shape magnets. The manufacture technology and properties testing method of composite powder and bonded NdFeB magnets from injection molding were described in detail. The effects of content of binder, additives and magnetic powder on the magnetic property, mechanical property and fluidity of injection molding magnets were investigated. Furthermore, the effect mechanism was revealed microcosmically. The injection molding bonded magnets were prepared by using the MQP-B rapidly quenching NdFeB magnetic powder and polyamide 12. The magnetic properties are: Br=0.539T, Hcb=345.37kA/m, Hci=681.02kA/m, and (BH)max=47.37kJ/m3.
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Qin, Wan Zhong, and Jie He. "Research on Composite Powder and Magnet Properties of Bonded NdFeB Magnets Prepared by Press Molding." Applied Mechanics and Materials 345 (August 2013): 218–22. http://dx.doi.org/10.4028/www.scientific.net/amm.345.218.
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The manufacture technology and properties testing method of composite powder and bonded NdFeB magnets from press molding were described in detail. The effects of the content of binder and additives, the molding pressure, the treatment of magnet surface on the mechanical property, processing property, magnetic property and anti-oxidation property of press molding magnets were investigated. Furthermore, the effect mechanism was revealed microcosmically. The press molding bonded magnets was prepared by using the MQP-B rapidly quenching NdFeB magnetic powder and epoxy binder. The magnetic properties are: Br = 0.722 T, Hcb = 457 kA/m, Hci = 718 kA/m, and (BH) max = 83.5 kJ/m3.
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Qin, Wan Zhong, Jie He, and Wen Tong Zhao. "Research on Compound Powder of Bonded NdFeB Magnets from Injection Molding." Advanced Materials Research 228-229 (April 2011): 841–46. http://dx.doi.org/10.4028/www.scientific.net/amr.228-229.841.
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The injection molding of magnetic powder could cost-effectively mass-produce net shape magnets. In order to prepare the injection molding bonded NdFeB permanent magnet material with better combined properties, the effect of binder on the magnetic property, mechanical property and fluidity of injection molding magnets and its mechanism microcosmically were investigated. The effect of additives such as silicone coupling agent, compound lubricants and antioxidant on the properties of injection molding magnets are discussed. The injection molding bonded magnets were prepared by using the MQP-B rapidly quenching NdFeB magnetic powder and polyamide 12. The magnetic properties are :Br=0.539T, Hcb=345.37kA/m, Hci=681.02kA/m, and (BH)max=47.37kJ/m3.
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Santos, Antônio Tomé R. M. dos, Eduardo Dias Coutinho, and Paulo Roberto da Costa Vieira. "SATISFAÇÃO DOS USUÁRIOS DO METRÔ DO RIO DE JANEIRO:." Revista Vianna Sapiens 8, no. 2 (2017): 20. http://dx.doi.org/10.31994/rvs.v8i2.238.
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A satisfação do cliente é de fundamental importância para garantir fluxo estável e crescente de consumidores, por meio da lealdade dos existentes e da comunicação oral positiva, atraindo novos clientes. O presente trabalho objetivou estudar a satisfação dos usuários de transporte público metroviário na cidade do Rio de Janeiro com os serviços prestados pelo MetrôRio. Na coleta de dados, empregou-se a pesquisa de survey, com utilização de questionário estruturado. Posteriormente, os dados foram tratados por meio da Modelagem de Equações Estruturais (MEE), com base em Mínimos Quadrados Parciais (MQP). Os resultados confirmaram que a satisfação do usuário sofre impacto estatisticamente significativo da qualidade do serviço, das expectativas e do valor percebido.
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Volegov, Aleksey S., Anton S. Bolyachkin, and Nikolay V. Kudrevatykh. "A New Method of Intergrain Exchange Interaction Energy Determination in Nanostructured Alloys with Spontaneous Spin-Reorientation Transition." Solid State Phenomena 233-234 (July 2015): 615–18. http://dx.doi.org/10.4028/www.scientific.net/ssp.233-234.615.
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A new method of intergrain exchange interaction energy determination in nanostructured magnetically hard alloys with spontaneous spin-reorientation transition has been developed and verified. It is based on the knowing of the material magnetic anisotropy constants values at its “easy cone” state and the external negative magnetic field strength H, which reversibly “tears” the exchange coupling between nanograins. It should be more than exchange field and smaller than coercivity value. Using this method the exchange interaction energy parameter for MQP-B+ alloy was estimated. Its value is in agreement with estimated one by FMR technique for film system Fe-Nd2Fe14B and close to that obtained from the remanent magnetization temperature dependences measurements in negative magnetic fields.
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Cavalcanti, Luiz Antonio Pimentel. "Protótipo para análise da qualidade de gasolina tipo C comum utilizando sensores de gás tipo semicondutor." Revista Brasileira de Gestão Ambiental e Sustentabilidade 6, no. 12 (2019): 109–16. http://dx.doi.org/10.21438/rbgas.061208.
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O controle da qualidade de combustíveis é um elemento de notável importância para o desenvolvimento econômico e ambiental de um país. Realizar esta análise de forma rápida e eficiente é um anseio crescente da sociedade, e acarreta a necessidade do desenvolvimento de tecnologias que possibilitem essa melhoria. O presente trabalho teve por objetivo avaliar o desempenho de sensores semicondutores em detectar adulteração da gasolina tipo C comum. Desenvolveu-se um protótipo compostos de uma câmara de gás onde foram fixados sensores da família MQ's (MQ2, MQ3, MQ4, MQ6, MQ7 e MQ9) e dois sensores DHT11 para medição de temperatura e umidade. O protótipo foi interligado a uma plataforma de microcontrolador Arduino e foram formuladas adulterações em amostras de gasolina tipo C comum nas proporções de 5%, 10%, 20%, 30% e 50% (m/m) de etanol anidro em base gravimétrica. As curvas de resposta dos sensores semicondutores demonstraram que o desempenho do protótipo foi satisfatório em identificar qualitativamente a adulteração do combustível.
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Zhang, Yun, Richen Lai, Qiang Chen, et al. "The Correlation Analysis of Microstructure and Tribological Characteristics of In Situ VCp Reinforced Iron-Based Composite." Materials 14, no. 15 (2021): 4343. http://dx.doi.org/10.3390/ma14154343.
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In this study, four kinds of heat treatments were performed to obtain a certain amount of retained austenite, which can result in good toughness and low brittleness accompanied with wear resistance of an in situ VC particle reinforced iron-based composite (VCFC). Microstructure, mechanical properties and wear resistance of the samples under heat treatment of QP, QPT, MQP and MQPT were compared. The experimental results indicated that there is a huge difference in microstructure between MQPT and the other heat treatments. High-proportion retained austenite and white net-like precipitates of M7C3 carbide existed in the MQPT-treated sample, but thick M7C3 carbide with brittleness was discovered in the other sample. Thereby, high-proportion retained austenite contributed to its low hardness of 634 HV and high tensile strength of 267 MPa, while a maximum hardness of 705.5 HV and a minimum tensile strength of 205 MPa were exhibited in the QPT-treated sample with a V-rich carbide of high hardness, a Cr-rich carbide of brittleness and a high-proportion martensite. Meanwhile, a phase transformation from retained austenite to martensite could increase the hardness and enhance wear resistance based on the transformation-induced plasticity (TRIP) effect; its wear rate was only 1.83 × 10−6 mm−3/(N·m). However, the wear rates of the samples under QP, QPT and MQP heat treatments increased by 16.4%, 44.3% and 41.0%, respectively. The wear mechanism was a synergistic effect of the adhesive wear mechanism and the abrasive wear mechanism. The adhesive wear mechanism was mainly considered in the MQPT-treated sample to reduce the wear rate attributed to high-proportion retained austenite and the existence of wear debris with a W element on the surface of the wear track. However, the abrasive wear mechanism could exist in the other samples because of a lot of thick, brittle M7C3, thereby resulting in a higher wear rate due to immediate contact between the designed material and the counterpart.
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Ferreira, Antonio Sergio Bolonha, Arthur Luiz Santana Moreira, Gédison Peixoto Oliveira Junior, and Paulo Roberto Da Costa Vieira. "IDENTIFICAÇÃO DE FATORES QUE INFLUENCIAM A INTENÇÃO DE USO DE COMENTÁRIOS DE VIAGEM ONLINE PARA ESCOLHA DE UM MEIO DE HOSPEDAGEM:." Revista Vianna Sapiens 9, no. 2 (2018): 25. http://dx.doi.org/10.31994/rvs.v9i2.377.
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O presente trabalho tem o propósito de analisar os fatores que influenciam a intenção de uso de Comentários de Viagens Online (CVO) na escolha de um meio de hospedagem. Para tal, foi realizada uma survey com amostra de conveniência constituída por 232 respondentes nas cidades do Rio de Janeiro e de Cabo Frio. Como instrumento de coleta de dados foi utilizado questionário estruturado, com respostas em escala Likert. O modelo conceitual de pesquisa é baseado no Modelo de Aceitação Tecnológica (TAM) e na Teoria Motivacional. Os resultados foram analisados utilizando Modelagem de Equações Estruturais (MEE) com base em mínimos quadrados parciais (MQP), ferramenta estatística para tratamento dos dados. Os resultados confirmaram que a intenção do usuário de usar CVO sofre impacto estatisticamente significativo da utilidade percebida, da facilidade percebida, atitude percebida e do prazer percebida.
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Duarte, André Luís Faria, Paulo Roberto da Costa Vieira, and Antonio Carlos Magalhães da Silva. "Dimensões que impactam a satisfação do usuário de sistema de informação acadêmica: Estudo com emprego de Modelagem de Equações Estruturais com base em Mínimos Quadrados Parciais." Exacta 14, no. 1 (2016): 139–48. http://dx.doi.org/10.5585/exactaep.v14n1.5963.
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A presente pesquisa foi realizada em uma universidade privada localizada na região da Baixada Fluminense, no estado do Rio de Janeiro, com o objetivo de verificar se as dimensões “qualidade do sistema”, “qualidade da informação”, “qualidade do serviço” e “utilidade percebida” do sistema de informação acadêmica (SAI) exercem impacto positivo na satisfação do usuário. Essas dimensões foram definidas a partir de modelo encontrado na literatura. Para tanto, foi conduzida pesquisa com abordagem quantitativa com utilização de questionário estruturado, sendo os dados tratados com a técnica de modelagem de equações estruturais (MEE), utilizando mínimos quadrados parciais (MQP). Como resultado, as hipóteses do estudo foram confirmadas, ou seja, as dimensões “qualidade do sistema”, “qualidade da informação”, “qualidade do serviço” e “utilidade percebida” exercem impacto positivo na satisfação do usuário do sistema de informação acadêmica (SIA).
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Aryanto, Didik, Zailani Ray, Toto Sudiro, Agus Sukarto Wismogroho, and Nanang Sudrajat. "The Effect of Powder Particle Size on the Structural and Magnetic Properties of Bonded NdFeB Magnet." Advanced Materials Research 1123 (August 2015): 88–91. http://dx.doi.org/10.4028/www.scientific.net/amr.1123.88.
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Commercially, NdFeB powder (type MQP-B+) with difference in particle sizes were used in this study. The powders were isotropically compressed and heat cured at 150°C for 30 minute. The samples were then magnetized and characterized by impulse magnetizer K series and permagraph MAGNET-PHYSIK Dr. Steingroever GmbH, respectively. According to the results of SEM characterization, compacted powder showed a homogeneous plate distribution. The surface morphology also indicated the presence of pores in the bonded NdFeB magnet. X-ray diffraction analysis from all samples revealed that the diffraction peaks were detected as tetragonal Nd2Fe14B-phase. There was no significant different in magnetic properties of bonded magnets with different in particle size. The optimum Br, Hcb, and (BH)max were achieved at particle size range of 150-297 mm.
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Bueno Baqués, D., J. A. Matutes Aquino, V. Coral Flores, and O. Ayala Valenzuela. "Efectos de la microestructura en las propiedades magnéticas de imanes híbridos de SrFe12O19/MQP-Q." Boletín de la Sociedad Española de Cerámica y Vidrio 44, no. 4 (2005): 228–30. http://dx.doi.org/10.3989/cyv.2005.v44.i4.435.
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Mulyadi, Mulyadi. "ANALISIS SIFAT MEKANIK, SIFAT FISIS DAN MAGNET KOMPOSIT MAGNET PERMANEN NdFeB DENGAN PEREKAT POLYVYNIL ALCOHOL (PVA)." Jurnal Teknik Mesin Cakram 2, no. 1 (2019): 29. http://dx.doi.org/10.32493/jtc.v2i1.2813.
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Abstrak: Pada penelitian ini dilakukan pembuatan komposit magnet permanen Nd2Fe14B dengan menggunakan perekat Poly vynil alcohol (PVA), dengan tujuan untuk mengetahui pengaruh variasi penambahan PVA terhadap sifat mekanik, sifat fisis dan magnet komposist magnet Nd2Fe14B. Bahan baku yang digunakan serbuk magnet Nd2Fe14B Type MQP-B dan perekatnya cairan PVA. Variasi komposi PVA adalah 2, 3, 5 , 7 dan 9 % berat. Kedua bahan baku dicampur sampai homogen, kemudian dicetak tekan dengan gaya 10 tonf membentuk pellet berdiameter 18 mm dan ketebalan 15 mm. Kemudian pellet yang diperoleh dikeringkan didalam lemari pengering pada suhu 100oC selama 2 jam. Pelet yang telah kering di magnetisasi sehingga manjadi magnet. Selanjutnya dilakukan karakterisasi meliputi pengujian kuat tekan dan kekerasan (shore hardness D ),serta diukur densitas dan kekeuatan medan magnet. Hasil diperoleh menunjukkan bahwa semakin banyak komposisi PVA maka kuat tekan dan kekerasan cenderung meningkat dan sebaliknya densitas dan sifat magnetnya cenderung menurun. Komposisi yang terbaik pada sampel dengan 2 % PVA dan diperoleh kuat medan magnet 1300 gauss.Kata kunci : komposit magnet, Nd2Fe14B, PVA, kuat tekan, kekerasan, kuat medan magnet
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Jokiniemi, Lotta, Jouni Suhonen та Hiroyasu Ejiri. "Magnetic HexadecapoleγTransitions and Neutrino-Nuclear Responses in Medium-Heavy Nuclei". Advances in High Energy Physics 2016 (2016): 1–8. http://dx.doi.org/10.1155/2016/8417598.
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Neutrino-nuclear responses in the form of squares of nuclear matrix elements, NMEs, are crucial for studies of neutrino-induced processes in nuclei. In this work we investigate magnetic hexadecapole (M4) NMEs in medium-heavy nuclei. The experimentally derived NMEs,MEXP(M4), deduced from observed M4γtransition half-lives are compared with the single-quasiparticle (QP) NMEs,MQP(M4), and the microscopic quasiparticle-phonon model (MQPM) NMEsMMQPM(M4). The experimentally derived M4 NMEs are found to be reduced by a coefficientk≈0.29with respect toMQP(M4) and byk≈0.33with respect toMMQPM(M4). The M4 NMEs are reduced a little by the quasiparticle-phonon correlations of the MQPM wave functions but mainly by other nucleonic and nonnucleonic correlations which are not explicitly included in the MQPM. The found reduction rates are of the same order of magnitude as those for magnetic quadrupoleγtransitions and Gamow-Teller (GT) and spin-dipole (SD)βtransitions. The impacts of the found reduction coefficients on the magnitudes of the NMEs involved in astroneutrino interactions and neutrinoless double beta decays are discussed.
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Alvarenga, Camila Cristina, Carlos Rogério de Mello, José Marcio de Mello, and Marcelo Ribeiro Viola. "Continuidade espacial da condutividade hidráulica saturada do solo na bacia hidrográfica do Alto Rio Grande, MG." Revista Brasileira de Ciência do Solo 35, no. 5 (2011): 1745–58. http://dx.doi.org/10.1590/s0100-06832011000500029.
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A distribuição espacial da condutividade hidráulica saturada (k0) é essencial para estudos relacionados a erosão do solo e escoamento superficial. Este trabalho objetivou estudar a continuidade espacial do atributo hidrológico do solo k o na Bacia Hidrográfica do Alto Rio Grande, MG, e realizar seu mapeamento por meio de técnicas geoestatísticas, utilizando dados sem e com transformação logarítmica. Os modelos de semivariograma esférico e exponencial foram ajustados ao semivariograma experimental pelo método dos Mínimos Quadrados Ordinários (MQO) e Mínimos Quadrados Ponderados (MQP). Técnicas de validação cruzada e preditiva foram aplicadas para a escolha do melhor modelo. Os resultados indicaram que, ao se trabalhar com o logaritmo dos dados de k o, houve redução de pontos discrepantes e de anisotropia, entretanto os valores mais elevados de grau de dependência espacial foram observados nos dados sem transformação. O ajuste do modelo esférico, por meio do método MQO, foi o que produziu melhor desempenho na modelagem da continuidade espacial de k0. Os mapas gerados a partir dos dados sem e com transformação logarítmica não apresentaram o mesmo comportamento na distribuição espacial dos valores, e o mapa dos dados na forma transformada teve o melhor detalhamento da distribuição espacial.
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Ma, Huiying, Xuejing Chen, Bangrong Lu, and Yanhong Ji. "Optical Thickness-Encoded Suspension Array for High-Throughput Multiplexed Gene Detection." Sensors 19, no. 24 (2019): 5425. http://dx.doi.org/10.3390/s19245425.
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We proposed a coding and decoding method of suspension array (SA) based on micro-quartz pieces (MQPs) with different optical thicknesses. The capture probes (cDNA) were grafted onto the surfaces of MQPs and specifically recognized and combined with the partial sequence of the target DNA (tDNA) to form a MQP-cDNA-tDNA complex. Quantum dot-labeled signal probes were then used to specifically recognize and bind another portion of the tDNA in the complex to form a double-probe sandwich structure. This optical thickness-encoded SA can be decoded and detected by a dual-wavelength digital holographic phase fluorescence microscope system. We conducted a series of DNA molecule detection experiments by using this encoding method. Control experiments confirmed the specificity of optical thickness-encoded SA in DNA detection. The concentration gradient experiments then demonstrated the response of the MQPs based SA to analyte concentration. Finally, we used the encoding method to detect three types of DNA in a single sample and confirmed the feasibility of the proposed optical thickness-encoded SA in multiplexed DNA detection. The detection results are stable, and the detection exhibits high specificity and good repeatability.
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Ritawanti, Arjuna, Kista Sembiring, Muljadi Muljadi, and Erfin Yundra Febrianto. "Pengaruh Ukuran Butir (grain size) pada pembuatan Bonded Magnet NdFeB." JURNAL IKATAN ALUMNI FISIKA 2, no. 1 (2016): 10. http://dx.doi.org/10.24114/jiaf.v2i1.3513.
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Telah dilakukan penelitian tentang pembuatan magnet permanen bonded NdFeB dengan polimer bakelit dilakukan dengan mencampurkan serbuk magnet Neodymiun Iron Boron (NdFeB) komersil tipe MQP-B+ dengan perekat menggunakan cetakan (moulding).Sebelum serbuk NdFeB di campur dilakukan pengayakan terhadap kedua serbuk .Komposisi bakelit sebesar 0, 2,5%, 5% dan 7,5 % berat dari massa total sampel 8 gram. Campuran ini kemudian dicetak dengan metode dry compression moulding dengan tekanan sampel 5 tonforce/cm² demgan menggunakan suhu hot press sebesar 120°C,140°C,160°C dan 180°C selama 30 menit.Disini untuk mengetahui pengaruh grain size di lakukan pengayakan dalam serbuk dalam ukuran 100 Mesh dan 200 Mesh. Setelah di dapatkan hasil sampel dalam bentuk pelet di simpan dalam ruang vakum Desicator untuk menghindari dari pengaruh oksidasi.Uji fisis dilakukan dalam penelitian ini dengan mengukur Bulk density dan melihat mikrostrukur dengan menggunakan SEM.Selanjutnya uji magnetisasi dilakukan untuk mengetahui sifat magnet yang terbaik dan karakterisasi magnet dilakukan magnet dilakukan dengan mengunakan Permagraph C untuk mengetahui nilai induksi remanensi (Br) dalam suatu medan magnet , koersivitas (Hc) dan Energi Produksi Maksimum (BH)max.Hasil penelitian di peroleh sifat magnet yang terbaik pada ukuran 100 Mesh Bakelit 2,5%wt pada suhu Hot press 160 °C menghasilkan nilai kuat magnet 1.633 Gauss, Br =3,72 kG,Hci = 7,557 KOe dan BHmax = 2,85 MGOe.
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Kadafi, Muammar, and Rachmad Almi Putra. "ELECTRONIC NOSE (E-NOSE) DESIGN FOR ARDUINO NANO-BASED HALAL HARAM IDENTIFICATION." Jurnal Neutrino 13, no. 1 (2021): 8–12. http://dx.doi.org/10.18860/neu.v13i1.8903.
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It has been successfully designed an Electronic Nose (e-Nose) instrumentation system consisting of 6 MQ gas sensors, namely, MQ2, MQ4, MQ5, MQ7, MQ9, MQ135. The E-nose system is used to identify halal-haram food. This E-Nose system uses an Arduino Nano microcontroller. The Graphic User Interface (GUI) system is built with Visual Studio 2008. Then, the data responses will be evaluated by using 2 patterns recognition methods called Principle Component Analysis (PCA). The classification results can be explained by the value of the score plot on the PCA of the data. PC1 accounts for 19% of the variance, and PC2 accounts for 5% of the variance, data obtained is stored and displayed on personal computers in Excel format. Each sample was tested for up to ten repetitions. The data obtained from the six sensors in the e-nose was processed using Minitab 18 and it was necessary to obtain classification data on lard, pig oil, and sample B, which were fried crackers using pork oil.
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Hidayat, Nurul, Samsul Hidayat, Nugroho Adi Pramono, and Ulfa Nadirah. "Sistem Deteksi Kebocoran Gas Sederhana Berbasis Arduino Uno." Rekayasa 13, no. 2 (2020): 181–86. http://dx.doi.org/10.21107/rekayasa.v13i2.6737.
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Penggunaan gas di berbagai sendi kehidupan manusia sekarang ini tidak dapat terhindarkan, mulai dari kebutuhan skala rumah tangga hingga industri. Dalam upaya meningkatkan pencegahan terjadinya kecelakaan kerja akibat kebocoran gas, kontrol terhadap kebocoran gas merupakan sebuah tindakan yang vital. Oleh karena itu, makalah ini membahas respon sensor gas MQ2, MQ3, dan MQ5 terhadap gas dan asap. Ketiga sensor gas tersebut dijalankan oleh mikrokontroler ATMega328 dengan modul Arduino Uno. Sebagai aktuator, buzzer digunakan sebagai pengirim sinyal audio dan LED sebagai basis informasi visual terkait pengingat adanya gas berlebih yang terdeteksi oleh MQ2, MQ3, dan MQ5. Secara mekanisme fisis, ketika sensor gas mendeteksi adanya gas berlebih, maka sinyal suara dari buzzer akan aktif sedemikian rupa sehingga dapat digunakan sebagai indikasi dini terhadap keberadaan atau kebocoran gas. Secara umum, sensor gas MQ2, MQ3, dan MQ5 memiliki respon yang sedikit berbeda pada jenis asap dan gas yang berbeda. Pada gilirannya nanti, hasil dari penelitian ini dirancang sebagai informasi penting dalam pemilihan jenis sensor gas sesuai kebutuhan. Simple Gas Leakage Detection System Based on Arduino UnoAbstractThe use of gas in various aspects of human life nowadays is inevitable, ranging from the needs of household scales to industries. As an effort to increase the prevention of occupational accidents due to gas leakage, control of gas leakage becomes a vital action. Therefore, this paper discusses the response of MQ2, MQ3, and MQ5 gas sensors to gases and smokes. The ATMega328 microcontroller ran the three gas sensors with the Arduino Uno module. As an actuator, buzzers were used as audio signal senders and LEDs as a basis for visual information related to reminders of excess gas detected by MQ2, MQ3, and MQ5. The physical mechanism, when the gas sensor detects the presence of excess gas, then the sound signal from the buzzer could be activated in such a way that it can be used as an early indication of the presence of leakage of gas. Generally, MQ2, MQ3, and MQ5 gas sensors performed slightly differently in responding to the presence of gases and smokes. In turn, the results of this study are designed as relevant information in selecting the type of gas sensor as needed.Keywords: Gas sensor, Microcontroller, MQ2, MQ3, MQ5, Simple instrumentation.
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Mendrofa, Mareanus, Perdinan Sinuhaji, and Muljadi Muljadi. "Study on the Production of Bonded Magnet NdFeB and Polyvinyl Butyral." Journal of Technomaterials Physics 2, no. 1 (2020): 25–33. http://dx.doi.org/10.32734/jotp.v2i1.5263.
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bonded magnet is composite magnet material made by mixing magnetic powder with non-magnetic binder. The process in manufacturing bonded magnet NdFeB made by mixing powder of neodymium iron boron (NdFeB) commercial type MQP-B with a polyvinyl butyral powder using a glass beaker. The comparisons of variation in composing NdFeB magnets powders with a binder of PVB (% weight) are 98:2, 96:4, 94:6 and 93:7 of 8 grams from total mass of the sample. After mixing the powder, it is molded by using a compression molding method with 8 tons pressure for 20 minutes at curing temperature 1600C. The molded samples are conducted by characterizing the physical properties which include measurement of density, microstructure analysis using SEM-EDX and magnetic properties which include measurement of the magnetic field strength using a Gaussmeter and hysteresis curve using VSM. The result of the study shows that the addition of and binder PVB in bonded magnet NdFeB causes a decrease in the density and magnetic field strength. The best result of density and magnetic field in the manufacture of bonded magnets is obtained by the addition of 2 % binder of 5.66 g/cm3 and strong magnetic field of 1862.4 G. the score of Mr = 72.86 emu/g, Ms = 103 emu/gram, Hc = 8.490 KOe and BHmax = 5.1 MGOe was obtained on the addition of PVB 2 %.
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Page, Patrick, Joshua DeJong, Alaina Bandstra, and Robert A. Boomsma. "Effect of Serum and Oxygen Concentration on Gene Expression and Secretion of Paracrine Factors by Mesenchymal Stem Cells." International Journal of Cell Biology 2014 (2014): 1–7. http://dx.doi.org/10.1155/2014/601063.
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Mesenchymal stem cells (MSC) secrete paracrine factors that may exert a protective effect on the heart after coronary artery occlusion. This study was done to determine the effect of hypoxia and serum levels on the mRNA expression and secretion of paracrine factors. Mouse bone marrow MSC were cultured with 5% or 20% serum and in either normoxic (21% O2) or hypoxic (1% O2) conditions. Expression of mRNA for vascular endothelial growth factor (VEGF), monocyte chemotactic protein-1 (MCP-1), macrophage inflammatory protein-1α(MIP-1α), MIP-1β, and matrix metalloproteinase-2 (MMP-2) was determined by RT-qPCR. Secretion into the culture media was determined by ELISA. Hypoxia caused a reduction in gene expression for MCP-1 and an increase for VEGF (5% serum), MIP-1α, MIP-1β, and MMP-2. Serum reduction lowered gene expression for VEGF (normoxia), MCP-1 (hypoxia), MIP-1α(hypoxia), MIP-1β(hypoxia), and MMP-2 (hypoxia) and increased gene expression for MMP-2 (normoxia). The level of secretion of these factors into the media generally paralleled gene expression with some exceptions. These data demonstrate that serum and oxygen levels have a significant effect on the gene expression and secretion of paracrine factors by MSC which will affect how MSC interactin vivoduring myocardial ischemia.
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Mardenli, Omar R. "The Progeny test of Friesian sires for milk traits by using the contemporary comparison method." Revista Colombiana de Ciencia Animal - RECIA 13, no. 1 (2021): e747. http://dx.doi.org/10.24188/recia.v13.n1.2021.747.
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In this study, the contemporary comparison method (CC) of half-sibs relation was used to estimate the breeding values of Holstein-Friesian sires for 305 -day milk yield (305-DMY) and basic components of milk traits, 409 records of cows that are daughters of ten sires in eight Syrian dairy farms where used. Result of the study showed differences in the estimated breeding values(ccEBVs), where the E Sire achieved the highest value of 305-DMY trait (254.47 kg), while the B Sire achieved the highest value of milk protein percentage (MPP), milk fat percentage (MFP)and milk lactose percentage (MLP) traits (0.822 %, 0.857 %and 1.09% respectively). According to their sires, daughters of E Sire outperformed the counterparts in the 305-DMY (p = 0.001), MPP (p = 0.001) and MFP (p = 0.04) traits (5701.44 kg, 3.55%, and 3.88% respectively). According to source of farm, daughters in Farm 5 achieved the highest value of 305-DMY trait (p=0.04) and daughters in the seventh farm achieved the highest value of MPP trait (p=0.007), the values were 5403.48 kg and 3.54 % respectively. Values of heritability (h2) for the traits of 305-DMY, MPP, MFP and MLP were 0.33,0.54,0.43 and 0.47 respectively. Most of genetic and phenotypic correlations coefficients were approaching to zero except the genetic relation between MLP and MPP and phenotypic relation between MFP and MPP (0.88 and 0.84 respectively).
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Ye, Dongping, Weiguo Liang, Libing Dai, and Yicun Yao. "Moderate Fluid Shear Stress Could Regulate the Cytoskeleton of Nucleus Pulposus and Surrounding Inflammatory Mediators by Activating the FAK-MEK5-ERK5-cFos-AP1 Signaling Pathway." Disease Markers 2018 (June 12, 2018): 1–9. http://dx.doi.org/10.1155/2018/9405738.
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We first applied moderate fluid shear stress to nucleus pulposus cells. The correlation of AP-1 with type II collagen, proteoglycan, Cytokeratin 8 protein, MAP-1, MAP-2, and MAP-4 and the correlation of AP-1 with IL-1β, TNF-α, IL-6, IL-8, MIP-1, MCP-1, and NO were detected. Our results document that moderate fluid shear stress could activate the FAK-MEK5-ERK5-cFos-AP1 signaling pathway. AP1 could downregulate the construct factors of cytoskeleton such as type II collagen, proteoglycan, Cytokeratin 8 protein, MAP-1, MAP-2, and MAP-4 in nucleus pulposus cell after the fluid shear stress was loaded. AP1 could upregulate the inflammatory factors such as IL-1β, TNF-α, IL-6, IL-8, MIP-1, MCP-1, and NO in nucleus pulposus cell after the fluid shear stress was loaded. Taken together, our data suggested that moderate fluid shear stress may play an important role in the cytoskeleton of nucleus pulposus and surrounding inflammatory mediators by activating the FAK-MEK5-ERK5-cFos-AP1 signaling pathway, thereby affecting cell degeneration.
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Ogata, Ryouji, Nobuhiko Hiramatsu, Kunihiro Hayakawa, et al. "Impairment of MCP-1 Expression in Mesothelial Cells Exposed to Peritoneal Dialysis Fluid by Osmotic Stress and Acidic Stress." Peritoneal Dialysis International: Journal of the International Society for Peritoneal Dialysis 31, no. 1 (2011): 80–89. http://dx.doi.org/10.3747/pdi.2009.00159.
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BackgroundBacterial peritonitis is one of the most frequent complications in patients on peritoneal dialysis. In the present study, we investigated effects of peritoneal dialysis fluid (PDF) on mesothelial cell recruitment of macrophages, focusing especially on unphysiological properties of PDF.MethodsHuman and murine mesothelial cells were exposed to PDF or individual properties of PDF (low pH, high glucose concentration, hyperosmolality, high lactate concentration) in vitro and in vivo, treated with inflammatory stimuli, and subjected to analyses of monocyte chemo-attractant protein-1 (MCP-1), nuclear factor-κB (NF-κB), mitogen-activated protein (MAP) kinases, and MAP kinase phosphatase-1 (MKP-1).ResultsWe found that intraperitoneal administration of PDF suppressed expression of MCP-1 and infiltration of mononuclear cells in the peritoneum of mice following injection with lipopolysaccharide. Among the unphysiological properties of PDF, low pH and hyperosmolality caused blunted induction of MCP-1 in cytokine-stimulated mesothelial cells. The attenuated response was ascribed to suppression of NF-κB by low pH and inhibition of p38 MAP kinase by hyperosmolality. Furthermore, the attenuated phosphorylation of p38 MAP kinase by osmotic stress was associated with induction of MKP-1.ConclusionThese results suggest a possibility that mesothelial cells exposed to PDF exhibit attenuated MCP-1 expression and consequent impairment of macrophage recruitment through dual mechanisms, that is, inhibition of NF-κB by acidic stress and blunted activation of p38 MAP kinase by osmotic stress. In patients on peritoneal dialysis, blunted expression of chemokines may lead to perturbation of bacterial clearance by macrophages in the peritoneal cavity.
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Uguccioni, Mariagrazia, Massimo D'Apuzzo, Marcel Loetscher, Beatrice Dewald та Marco Baggiolini. "Actions of the chemotactic cytokines MCP-1, MCP-2, MCP-3, RANTES, MIP-1α and MIP-1β on human monocytes". European Journal of Immunology 25, № 1 (1995): 64–68. http://dx.doi.org/10.1002/eji.1830250113.
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Konenkov, Konenkov V. I., Koroleva E. G. Koroleva, Orlov N. B. Orlov та ін. "Changes in the serum concentrations of CCL chemokines (MCP-1, MIP-1α, MIP-1β, RANTES, and EOTAXIN) in women with uterine myoma". Akusherstvo i ginekologiia 8_2019 (1 вересня 2019): 107–11. http://dx.doi.org/10.18565/aig.2019.8.107-111.
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Zhang, Jizhou, Qingqing Wu, Courtney Johnson, et al. "In Situ Fate Mapping of Native and Stress Myelopoiesis Reveals a Unique Niche for Mono- and Dendritic Cell -Poiesis." Blood 136, Supplement 1 (2020): 38–39. http://dx.doi.org/10.1182/blood-2020-143123.
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In contrast to virtually all other tissues in the body the anatomy of differentiation in the bone marrow remains unknown. This is due to the lack of strategies to examine blood cell production in situ, which are required to better understand differentiation, lineage commitment decisions, and to define how spatial organizing cues inform tissue function. We developed approaches to image and fate map -using confetti mice- myelopoiesis in situ and generated 3D atlases of granulocyte and monocyte/dendritic cell differentiation during homeostasis and after emergency myelopoiesis induced by infection with Listeria monocytogenes. Figure 1 shows stepwise differentiation during myelopoiesis. We have found that -in imaging studies- CD11b-Ly6C-CD117+CD115+ cells are MDP; Lin-CD117+CD16/32+CD115- cells are GMP; CD11b-Ly6C+CD117+CD115+ are MOP; CD11b-CD117+CD115-Ly6C+ are GP; CD11b+CD115+Ly6Chi and CD11b+CD115+Ly6Clo cells are Ly6Chi and Ly6Clo monocytes; and MHCIIhi reticular cells are dendritic cells (DC). We used these markers to map every myeloid cell in the sternum and assessed the relationships between myeloid progenitors, their offspring and candidate niches in situ with single cell resolution. To test whether the interactions observed were specific we obtained the X, Y and Z coordinates for every hematopoietic cell in the sternum (detected using αCD45 and αTer119). We then used these coordinates to randomly place each type of myeloid cell, at the same frequencies found in vivo, through the BM to generate random distributions for each myeloid cell type. We found that myeloid progenitors do not localize with HSC indicating that they leave the HSC niche during differentiation. In the steady-state GP, MOP, and MDP are found as single cells that do not associate with each other indicating that granulo-, mono-, and dendritic cell-poiesis take place in different location. Myeloid progenitors are specifically recruited to sinusoids but are depleted near endosteum and arterioles (e.g. mean MDP distance to sinusoids, arterioles, and endosteum observed 5, 134, and 105μm vs 9, 86, and 69µm in the random simulation). GP form clusters with preneutrophils and immature neutrophils, in situ fate mapping demonstrated that these clusters are oligoclonal and that additional GP are serially recruited to the cluster as the old ones differentiate. Ly6Clo monocytes and dendritic cells are selectively enriched near MDP (2.0 DC and 4.4 Ly6Clo monocytes observed within 50µm of an MDP vs 0.9 DC and 1.8 Ly6Clo monocytes in the random simulation p=0.02 and p<0.0001). Fate mapping experiments demonstrated that the monocytes around MOP and monocytes and dendritic cells around the MDP are oligoclonal but are not the derived from the MOP/MDP they associate with. These indicate that Ly6Clo monocytes and DC are produced elsewhere but are then selectively recruited to regions enriched in MDP. The results above suggest that different sinusoids might be responsible for supporting different myeloid lineages. We found that dendritic cells localize to a unique subset (8% of all vessels) of colony stimulating factor 1 (CSF1, the major regulator of monopoiesis) -expressing sinusoids. Csf1 deletion in the vasculature disrupted MDP interaction with sinusoids, leading to reduced MDP numbers and differentiation ability, with subsequent loss of Ly6Clo monocytes and dendritic cells. L. monocytogenes infection dramatically changed the architecture of myelopoiesis and caused massive expansion of myeloid progenitors leading to the formation of monoclonal GP clusters and oligoclonal MOP clusters whereas MDP are still found as single cells associated with dendritic cells. Even after this massive insult granulopoiesis and mono/DC poiesis remained spatially segregated to different sinusoids. Csf1 deletion in the vasculature prevented generation of MDP and dendritic cells in response to infection. In summary we have developed strategies to image and fate map myelopoiesis in situ; revealed spatial segregation of -and distinct clonal architectures for- granulopoiesis and mono/DCpoiesis; and identified rare CSF1+ sinusoids that maintain mono/DCpoiesis in the steady-state and after infection. These data indicate that there is a specific spatial organization of definitive hematopoiesis and that local cues produced by distinct blood vessels are responsible for this organization. Figure Disclosures No relevant conflicts of interest to declare.
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Whitney, Darryl, David Klein, Tiffany Rodriguez, Lena Kenny, Eric Strauss, and Matthew Kingery. "Synovial Fluid Biomarkers in the Osteoarthritic Knee: Differences in Concentration with Progression of Radiographic Severity." Orthopaedic Journal of Sports Medicine 8, no. 7_suppl6 (2020): 2325967120S0044. http://dx.doi.org/10.1177/2325967120s00446.
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Objectives: The purpose of the current study was to analyze the synovial fluid concentrations of known inflammatory biomarkers in the setting of symptomatic osteoarthritis (OA) of the knee and assess for any differences in biomarker concentrations based on the extent of radiographic disease. Methods: Patients presenting with knee complaints were invited to provide synovial fluid samples from the symptomatic knee during their initial office visit. For this study, a subset of patients with OA was analyzed. The concentration of 16 synovial fluid biomarkers was measured, including TIMP-1, TIMP-2, TIMP-3, MMP-13, IL-6, MCP-1, MIP-1β, VEGF, bFGF, eotaxin, IL-1Ra, MMP-1, MMP-3, MMP-9, RANTES, and TSG-6. Samples were analyzed using a multiplex magnetic bead immunoassay. Patients were divided into a low-grade OA group (K-L ≤ 2 or OARSI ≤ 1) or a high-grade cartilage OA group (K-L ≥ 3 or OARSI ≥ 2). Results: 101 patients were included in this analysis. There was a significant difference in MIP-1β (p=0.025) and bFGF (p=0.015) concentrations between OARSI grade groups. Patients with high-grade joint space narrowing had significantly greater concentrations of MIP-1β (p=0.022) and bFGF (p=0.003). There was a significant difference in MIP-1β concentration between K-L grade groups (p=0.013). Patients in the high-grade K-L group had a significantly greater concentration of MIP-1β (p=0.020). Conclusions: The synovial fluid concentrations of two synovial fluid biomarkers were found to differ significantly based on the extent of radiographic OA present. MIP-1β is a pro-inflammatory growth factor known to induce the synthesis of other inflammatory factors including interleukins and TNF-α. bFGF is a growth factor that is known to promote chondrogenesis, angiogenesis, wound healing, and granulation tissue formation. Continued study of synovial fluid biomarkers in the setting of symptomatic OA may improve our understanding of the pathogenesis of disease and identify treatment targets in an attempt to halt disease progression.
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McQuibban, G. Angus, Jiang-Hong Gong, Julie P. Wong, John L. Wallace, Ian Clark-Lewis, and Christopher M. Overall. "Matrix metalloproteinase processing of monocyte chemoattractant proteins generates CC chemokine receptor antagonists with anti-inflammatory properties in vivo." Blood 100, no. 4 (2002): 1160–67. http://dx.doi.org/10.1182/blood.v100.4.1160.h81602001160_1160_1167.
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Monocyte chemoattractant protein (MCP)–3 is inactivated upon cleavage by the matrix metalloproteinase (MMP) gelatinase A (MMP-2). We investigated the susceptibility to proteolytic processing of the 4 human MCPs by 8 recombinant MMPs to determine whether MCP-3 is an isolated example or represents a general susceptibility of chemokines to proteolytic inactivation by these important inflammatory proteases. In addition to MMP-2, MCP-3 is efficiently cleaved by membrane type 1 (MT1)–MMP, the cellular activator of MMP-2, and by collagenase-1 and collagenase-3 (MMP-1, MMP-13) and stromelysin-1 (MMP-3). Specificity was shown by absence of cleavage by matrilysin (MMP-7) and the leukocytic MMPs neutrophil collagenase (MMP-8) and gelatinase B (MMP-9). The closely related chemokines MCP-1, MCP-2, and MCP-4 were not cleaved by MMP-2 or MT1-MMP, but were cleaved by MMP-1 and MMP-3 with varying efficiency. MCPs were typically cleaved between residues 4 and 5, but MCP-4 was further processed at Val7-Pro8. Synthetic MCP analogs corresponding to the MMP-cleaved forms bound CC chemokine receptor (CCR)–2 and CCR-3, but lacked chemoattractant activity in pre-B cells transfected with CCR-2 and CCR-3 or in THP-1 monocytic cells, a transformed leukemic cell line. Moreover, the truncated products of MCP-2 and MCP-4, like MCP-3, were potent antagonists of their cognate CC chemokine receptors in transwell cell migration assays in vitro. When they were injected 24 hours after the initiation of carrageenan-induced inflammation in rat paws, their in vivo antagonist activities were revealed by a greater than 66% reduction in inflammatory edema progression after 12 hours. We propose that MMPs have an important role in modulating inflammatory and immune responses by processing chemokines in wound healing and in disease.
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Ewins, J. P., M. D. Waller, M. White, and P. F. Lister. "MIP-map level selection for texture mapping." IEEE Transactions on Visualization and Computer Graphics 4, no. 4 (1998): 317–29. http://dx.doi.org/10.1109/2945.765326.
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Trappanese, Danielle M., Sarah Sivilich, Hillevi K. Ets, Farah Kako, Michael V. Autieri, and Robert S. Moreland. "Regulation of mitogen-activated protein kinase by protein kinase C and mitogen-activated protein kinase phosphatase-1 in vascular smooth muscle." American Journal of Physiology-Cell Physiology 310, no. 11 (2016): C921—C930. http://dx.doi.org/10.1152/ajpcell.00311.2015.
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Vascular smooth muscle contraction is primarily regulated by phosphorylation of myosin light chain. There are also modulatory pathways that control the final level of force development. We tested the hypothesis that protein kinase C (PKC) and mitogen-activated protein (MAP) kinase modulate vascular smooth muscle activity via effects on MAP kinase phosphatase-1 (MKP-1). Swine carotid arteries were mounted for isometric force recording and subjected to histamine stimulation in the presence and absence of inhibitors of PKC [bisindolylmaleimide-1 (Bis)], MAP kinase kinase (MEK) (U0126), and MKP-1 (sanguinarine) and flash frozen for measurement of MAP kinase, PKC-potentiated myosin phosphatase inhibitor 17 (CPI-17), and caldesmon phosphorylation levels. CPI-17 was phosphorylated in response to histamine and was inhibited in the presence of Bis. Caldesmon phosphorylation levels increased in response to histamine stimulation and were decreased in response to MEK inhibition but were not affected by the addition of Bis. Inhibition of PKC significantly increased p42 MAP kinase, but not p44 MAP kinase. Inhibition of MEK with U0126 inhibited both p42 and p44 MAP kinase activity. Inhibition of MKP-1 with sanguinarine blocked the Bis-dependent increase of MAP kinase activity. Sanguinarine alone increased MAP kinase activity due to its effects on MKP-1. Sanguinarine increased MKP-1 phosphorylation, which was inhibited by inhibition of MAP kinase. This suggests that MAP kinase has a negative feedback role in inhibiting MKP-1 activity. Therefore, PKC catalyzes MKP-1 phosphorylation, which is reversed by MAP kinase. Thus the fine tuning of vascular contraction is due to the concerted effort of PKC, MAP kinase, and MKP-1.
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Dahinden, C. A., T. Geiser, T. Brunner, et al. "Monocyte chemotactic protein 3 is a most effective basophil- and eosinophil-activating chemokine." Journal of Experimental Medicine 179, no. 2 (1994): 751–56. http://dx.doi.org/10.1084/jem.179.2.751.
Full textAbstract:
CC chemokines constitute a novel class of cytokines that attract and activate monocytes and lymphocytes, as well as basophil and eosinophil leukocytes, with distinct target cell profiles, and are believed to be involved in the regulation of different types of inflammation. The action of the recently identified monocyte chemotactic protein 3 (MCP-3) on human basophil and eosinophil function was studied and compared with that of other CC chemokines. In basophils, MCP-3, MCP-1, RANTES, and macrophage inflammatory protein (MIP)-1 alpha all induced cytosolic-free calcium concentration ([Ca2+]i) changes and, with different efficacies, chemotaxis (RANTES = MCP-3 > MCP-1 > MIP-1 alpha), histamine release (MCP-1 = MCP-3 > RANTES > MIP-1 alpha), and leukotriene C4 formation, after IL-3 pretreatment (MCP-1 = MCP-3 > RANTES > MIP-1 alpha). Thus, MCP-3 was as effective as MCP-1 as an inducer of mediator release, and as effective as RANTES as a stimulus of basophil migration. In contrast to MCP-1, MCP-3 was also a stimulus for eosinophils, and induced [Ca2+]i changes and chemotaxis as effectively as RANTES, which is the most potent chemotactic cytokine for these cells. Desensitization of the transient changes in [Ca2+]i was used to assess receptor usage. In basophils, stimulation with MCP-3 prevented responsiveness to MCP-1 and RANTES, but not to MIP-1 alpha. No single CC chemokine (except for MCP-3 itself) affected the response to MCP-3, however, which was prevented only when the cells were prestimulated with both MCP-1 and RANTES. In eosinophils, by contrast, cross-desensitization between RANTES and MCP-3 was obtained. RANTES and to a lesser extent MCP-3 also desensitized eosinophils toward MIP-1 alpha. The desensitization data suggest the existence of three chemokine receptors: (a) a MCP-1 receptor expressed on basophils but not eosinophils that is activated by MCP-1 and MCP-3; (b) a RANTES receptor in basophils and eosinophils that is activated by RANTES and MCP-3; and (c) a MIP-1 alpha receptor that is activated by MIP-1 alpha, RANTES and, more weakly, by MCP-3. This study shows that MCP-3 combines the properties of RANTES, a powerful chemoattractant, and MCP-1, a highly effective stimulus of mediator release, and thus has a particularly broad range of activities toward both human basophil and eosinophil leukocytes.
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Smirnov, Ivan E., L. M. Roshal, V. A. Mitish, A. G. Kucherenko, O. V. Karaseva, and I. V. Ponina. "MATRIX METALLOPROTEINASES IN CHILDREN WITH A COMBINED BONE INJURY." Russian Pediatric Journal 22, no. 3 (2019): 170–75. http://dx.doi.org/10.18821/1560-9561-2019-22-3-170-175.
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There were comprehensively examined 55 children, including 35 children with combined bone injury (average age of 12.6 ± 2.3 years), reference group consisted of 20 apparently healthy children (average age of 11.8 ± 2.7 years) without pathology of the motor system. on the 1-3rd and 30th day after the combined bone injury, changes in the content of matrix metalloproteinases (MMP) and cytokines - transforming growth factor-beta (TGF-β), monocytic chemotactic factor (MCP-1) and macrophage inflammatory protein (MIP-1β) were followed in the dynamics by serum immunoassay determination. It was established that after combined bone injury at the stage of post-traumatic formation of the regenerate by 30th days the serum concentrations of gelatinases (MMP-2, MMP-9) and collagenases (MMP-8) significantly increased, the levels of stromelysins (MMP-3) did not change, and the content of TIMP-1 decreased. Early detection of changes in the blood content of bone biomarkers during the recovery process after a combined trauma in children allows the timely implementing the correction of disturbances and the choice of the optimal individual treatment tactics for a particular patient, taking into account the features of his bone metabolism.
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Ghosh, Asish K., Mainak Majumder, Robert Steele, Robert A. White, and Ratna B. Ray. "A Novel 16-Kilodalton Cellular Protein Physically Interacts with and Antagonizes the Functional Activity of c-myc Promoter-Binding Protein 1." Molecular and Cellular Biology 21, no. 2 (2001): 655–62. http://dx.doi.org/10.1128/mcb.21.2.655-662.2001.
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ABSTRACT We initially identified c-myc promoter-binding protein 1 (MBP-1) from a human cervical carcinoma cell expression library which negatively regulates c-myc promoter activity. A recent study demonstrated that MBP-1 acts as a general transcriptional repressor (A. K. Ghosh, R. Steele, and R. B. Ray, Mol. Cell. Biol. 19:2880–2886, 1999). In order to identify the cellular protein(s) interacting with MBP-1 for transcriptional regulation, a HeLa cell cDNA expression library was screened using a yeast two-hybrid system. An MBP-1-interacting cDNA encoding a polypeptide of 140 amino acid residues with an approximate molecular mass of 16 kDa was identified and named MBP-1 interacting protein-2A (MIP-2A). MIP-2A has a sequence similarity with an unknown mRNA and SEDL. Mutations in the SEDL gene, located at human chromosome Xp22, has recently been implicated with an X-linked genetic disease, although the function of SEDL gene product was not determined (A. K. Gedeon et al., Nat. Genet. 22:400–404, 1999). However, our results suggested the localization of MIP-2A at human chromosome 19. The specificity of interaction between MBP-1 and MIP-2A was verified by an in vitro glutathione S-transferase pulldown experiment, a mammalian two-hybrid analysis, and in vivo coimmunoprecipitation assays. Further analysis revealed that the amino-terminal domain of MBP-1 (amino acids 1 to 95) interacts with MIP-2A. Immunofluorescent staining suggested colocalization of MIP-2A and MBP-1 primarily in the perinuclear membrane of cells. Functional analysis demonstrated that MIP-2A relieves MBP-1 mediated transcriptional repression on c-mycpromoter. Additionally, MIP-2A antagonizes cell growth regulatory role of MBP-1. Taken together, these results suggest the functional interaction of MIP-2A and MBP-1 in cell growth regulation.
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Gururajan, N., and M. Sambassivame. "Chaos-Logistic Map-Tent Map -Corresponding Cellular Automata." Mapana - Journal of Sciences 9, no. 2 (2010): 28–34. http://dx.doi.org/10.12723/mjs.17.4.
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We study the characteristic features of Tent Mop and Logistic Map towards Chaos. Cellular Automata is obtained for Tent Mop and Logistic Map. The behavior of Tent Mop and Logistic Mop is reflected in the Cellular Automata generated.
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Philipova, R., and M. Whitaker. "MAP kinase activity increases during mitosis in early sea urchin embryos." Journal of Cell Science 111, no. 17 (1998): 2497–505. http://dx.doi.org/10.1242/jcs.111.17.2497.
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A MBP kinase activity increases at mitosis during the first two embryonic cell cycles of the sea urchin embryo. The activity profile of the MBP kinase is the same both in whole cell extracts and after immunoprecipitation with an anti-MAP kinase antibody (2199). An in-gel assay of MBP activity also shows the same activity profile. The activity is associated with the 44 kDa protein that cross-reacts with anti-MAP kinase antibodies. The 44 kDa protein shows cross-reactivity to anti-phosphotyrosine and MAP kinase-directed anti-phosphotyrosine/phosphothreonine antibodies at the times that MBP kinase activity is high. The 2199 antibody co-precipitates some histone H1 kinase activity, but the MBP kinase activity cannot be accounted for by histone H1 kinase-dependent phosphorylation of MBP. The MAP kinase 2199 antibody was used to purify the MBP kinase activity. Peptide sequencing after partial digestion shows the protein to be homologous to MAP kinases from other species. These data demonstrate that MAP kinase activation during nuclear division is not confined to meiosis, but also occurs during mitotic cell cycles. MAP kinase activity in immunoprecipitates also increases immediately after fertilization, which in the sea urchin egg occurs at interphase of the cell cycle. Treating unfertilized eggs with the calcium ionophore A23187 stimulates the increase in MAP kinase activity, demonstrating that a calcium signal can activate MAP kinase and suggesting that the activation of MAP kinase at fertilization is due to the fertilization-induced increase in cytoplasmic free calcium concentration. This signalling pathway must differ from the pathway responsible for calcium-induced inactivation of MAP kinase activity that is found in eggs that are fertilized in meiotic metaphase.
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Elbedri Abdalla, Omer Abdalla, and Omer A. Musa. "Variability of lung function and respiratory muscles power in healthy and asthmatic subjects." Journal of Lung, Pulmonary & Respiratory Research 6, no. 3 (2019): 64–67. http://dx.doi.org/10.15406/jlprr.2019.06.00209.
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Airway function is one of the many biologic functions that exhibit circadian variability over 24-h periods. Studies of circadian variability of lung function in normal subjects as well as asthmatics are particularly scarce, and those of MEP and MIP are unknown. The aim of this study to determine circadian variation in lung function (FVC, FEV1 and PEFR) and respiratory muscle pressures(MEP and MIP) for measurement of respiratory muscle power at 6:00am (early morning),12:00midday, 6:00pm( evening) and 12:00 midnight in healthy subjects and in patients with mild asthma at 6:00am and 6:00pm , to elaborate on the possibility of using MEP and MIP variability as a new diagnostic test for asthma. This is a cross sectional study performed in Khartoum, the capital of Sudan during December 2010. Thirty healthy, symptoms free non smokers normal subjects aged 20-64 years selected randomly and 15 mild asthmatics, clinically free during the time of study aged 19-49 years were included in the study. There is significant drop in healthy subjects early in the morning compared to 6:00pm, the drop in FVC was 9.75%, in FEV1 was 8.79%, in PEFR was 8.44%, in MEP was 10.04%, and in MIP was 17.57%. There is also significant drop in asthmatics early in the morning in MEP and MIP (21.76%, 27.57% respectively), is comparable to FEV1 (22.56%) and PEFR (23.86%). The sensitivity and specificity of variability for MEP (53%, 77%) and MIP (60%, 63%) comparable to sensitivity and specificity of FEV1 variability (40%, 86%) and PEFR variability (46%, 73%). The obtained comparable results of MEP, MIP variability to FEV1, PEFR variability in normal and asthmatic subjects could imply that MEP & MIP can be used in assessing airway calibre as in asthma. The study concluded that MEP & MIP variability could be sensitive tests to confirm asthma diagnosis.
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Blanpain, Cédric, Isabelle Migeotte, Benhur Lee, et al. "CCR5 Binds Multiple CC-Chemokines: MCP-3 Acts as a Natural Antagonist." Blood 94, no. 6 (1999): 1899–905. http://dx.doi.org/10.1182/blood.v94.6.1899.
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Abstract CCR5 was first characterized as a receptor for MIP-1, MIP-1β, and RANTES, and was rapidly shown to be the main coreceptor for M-tropic human immunodeficiency virus (HIV)-1 strains and simian immunodeficiency virus (SIV). Chemokines constitute a rapidly growing family of proteins and receptor-chemokine interactions are known to be promiscuous and redundant. We have therefore tested whether other CC-chemokines could bind to and activate CCR5. All CC-chemokines currently available were tested for their ability to compete with [125I]-MIP-1β binding on a stable cell line expressing recombinant CCR5, and/or to induce a functional response in these cells. We found that in addition to MIP-1β, MIP-1, and RANTES, five other CC-chemokines could compete for [125I]-MIP-1β binding: MCP-2, MCP-3, MCP-4, MCP-1, and eotaxin binding was characterized by IC50 values of 0.22, 2.14, 5.89, 29.9, and 21.7 nmol/L, respectively. Among these ligands, MCP-3 had the remarkable property of binding CCR5 with high affinity without eliciting a functional response, MCP-3 could also inhibit the activation of CCR5 by MIP-1β and may therefore be considered as a natural antagonist for CCR5. It was unable to induce significant endocytosis of the receptor. Chemokines that could compete with high affinity for MIP-1β binding could also compete for monomeric gp120 binding, although with variable potencies; maximal gp120 binding inhibition was 80% for MCP-2, but only 30% for MIP-1β. MCP-3 could compete efficiently for gp120 binding but was, however, found to be a weak inhibitor of HIV infection, probably as a consequence of its inability to downregulate the receptor.
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Blanpain, Cédric, Isabelle Migeotte, Benhur Lee, et al. "CCR5 Binds Multiple CC-Chemokines: MCP-3 Acts as a Natural Antagonist." Blood 94, no. 6 (1999): 1899–905. http://dx.doi.org/10.1182/blood.v94.6.1899.418k31_1899_1905.
Full textAbstract:
CCR5 was first characterized as a receptor for MIP-1, MIP-1β, and RANTES, and was rapidly shown to be the main coreceptor for M-tropic human immunodeficiency virus (HIV)-1 strains and simian immunodeficiency virus (SIV). Chemokines constitute a rapidly growing family of proteins and receptor-chemokine interactions are known to be promiscuous and redundant. We have therefore tested whether other CC-chemokines could bind to and activate CCR5. All CC-chemokines currently available were tested for their ability to compete with [125I]-MIP-1β binding on a stable cell line expressing recombinant CCR5, and/or to induce a functional response in these cells. We found that in addition to MIP-1β, MIP-1, and RANTES, five other CC-chemokines could compete for [125I]-MIP-1β binding: MCP-2, MCP-3, MCP-4, MCP-1, and eotaxin binding was characterized by IC50 values of 0.22, 2.14, 5.89, 29.9, and 21.7 nmol/L, respectively. Among these ligands, MCP-3 had the remarkable property of binding CCR5 with high affinity without eliciting a functional response, MCP-3 could also inhibit the activation of CCR5 by MIP-1β and may therefore be considered as a natural antagonist for CCR5. It was unable to induce significant endocytosis of the receptor. Chemokines that could compete with high affinity for MIP-1β binding could also compete for monomeric gp120 binding, although with variable potencies; maximal gp120 binding inhibition was 80% for MCP-2, but only 30% for MIP-1β. MCP-3 could compete efficiently for gp120 binding but was, however, found to be a weak inhibitor of HIV infection, probably as a consequence of its inability to downregulate the receptor.