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Role of sex hormones in gastrointestinal motility in pregnant and non-pregnant rats

World Journal of Gastroenterology 2016年第25期22卷 5761-5768页

作者： Juliana Fernandes matos madileine Francely Americo Yuri Karen Sinzato Gustavo Tadeu Volpato Luciana Aparecida Corá marcos Felipe Freitas Calabresi ricardo Brandt Oliveira Debora Cristina Damasceno Jose ricardo Arruda miranda Sao Paulo State University BotucatuSP 18618-970Brazil Instituto de Ciencias Biologicas e da Saude Federal University of Mato GrossoBarra do GarcasMT 78600-000Brazil Universidade Estadual de Ciencias da Saude de Alagoas MaceioAL 57010-300Brazil Sao Paulo University Ribeirao PretoSP 14049-900Brazil

AIm: To correlate gastric contractility, gastrointestinal transit, and hormone levels in non-pregnant(estrous cycle) and pregnant rats using noninvasive techniques. mETHODS: Female rats(n = 23) were randomly divided into(1) non-pregnant,(contractility, n =6; transit, n = 6); and(2) pregnant(contractility, n = 5; transit, n = 6). In each estrous cycle phase or at 0, 7, 14, and 20 d after the confirmation of pregnancy, gastrointestinal transit was recorded by AC biosusceptometry(ACB), and gastric contractility was recorded by ACB and electromyography. After each recording, blood samples were obtained for progesterone and estradiol determination. RESULTS: In the estrous cycle, despite fluctuations of sex hormone levels, no significant changes in gastrointestinal motility were observed. Days 7 and 14 of pregnancy were characterized by significant changes in the frequency of contractions(3.90 ± 0.42 cpm and 3.60 ± 0.36 cpm vs 4.33 ± 0.25 cpm) and gastric emptying(168 ± 17 min and 165 ± 15 min vs 113 ± 15 min) compared with day 0. On these same days, progesterone levels significantly increased compared with control(54.23 ± 15.14 ng/m L and 129.96 ± 30.52 ng/mL vs 13.25 ± 6.31 ng/mL). On day 14, we observed the highest level of progesterone and the lowest level of estradiol compared with day 0(44.3 ± 15.18 pg/mL vs 24.96 ± 5.96 pg/mL). CONCLUSION: Gastrointestinal motility was unaffected by the estrous cycle. In our data, high progesterone and low estradiol levels can be associated with decreased contraction frequency and slow gastric emptying.

关键词： Reproductive physiological process Sex hormones Gastrointestinal motility magnetic fields Gastric emptying

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Printing accuracy tracking with 2D optical microscopy and super-resolution metamaterial-assisted 1D terahertz spectroscopy

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npj Flexible Electronics 2020年第1期4卷 178-184页

作者： mariia Zhuldybina Xavier Ropagnol ChloéBois ricardo J.Zednik François Blanchard Département de génieélectrique École de technologie supérieure(ÉTS)MontréalQCCanada Institut national de la recherche scientifique Énergiematériaux et télécommunications(INRS-EMT)VarennesQCCanada Institut des Communications Graphiques et de l’imprimabilité MontréalQCCanada Collège Ahuntsic MontréalQCCanada Département de génie mécanique École de technologie supérieure(ÉTS)MontréalQCCanada

Printable electronics is a promising manufacturing technology for the potential production of low-cost flexible electronic devices,ranging from displays to active *** is known that rapid printing of conductive ink on a flexible substrate is vulnerable to several sources of variation during the manufacturing ***,this process is still not being subjected to a quality control method that is both non-invasive and in *** address this issue,we propose controlling the printing accuracy by monitoring the spatial distribution of the deposited ink using terahertz(THz)*** parameters studied are the printing speed of an industrial roll-to-roll press with flexography printing units and the pre-calibration compression,or expansion factor,for a pattern printed on a flexible plastic *** pattern,which is carefully selected,has Babinet’s electromagnetic transmission properties in the THz frequency *** validate our choice,we quantified the geometric variations of the printed pattern by visible microscopy and compared its accuracy using one-dimensional THz *** study shows a remarkable agreement between visible microscopic observation of the printing performance and the signature of the THz ***,under specific conditions,one-dimensional(1D)THz information from a resonant pattern can be more accurate than two-dimensional(2D)microscopy *** result paves the way for a simple strategy for non-invasive and contactless in situ monitoring of printable electronics production.

关键词： printing visible pattern

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WEIGHTED A PRIORI ESTImATES FOR SOLUTION OF （-△）^mu = f WITH HOmOGENEOUS DIRICHLET CONDITIONS

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Analysis in Theory and Applications 2010年第4期26卷 339-349页

作者： ricardo G. Durn marcela Sanmartino marisa Toschi Facultad de Ciencias Exactas y Naturales Universidad De Buenon Aires Facultad De Ciencias Exactas Universidad Nacional De La Plata

Let u be a weak solution of （-△）mu = f with Dirichlet boundary conditions in a smooth bounded domain Ω C Rn. Then, the main goal of this paper is to prove the following a priori estimate：｜｜u｜｜w2m/ω·p（Ω）... 详细信息

关键词： Dirichlet problem Green function Calderon-Zygmund theory weightedSobolev space

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Fatty acid oxidation and autophagy promote endoxifen resistance and counter the effect of AKT inhibition in ER-positive breast cancer cells

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Journal of molecular Cell Biology 2021年第6期13卷 433-444页

作者： Lei Duan Sarah Calhoun Daeun Shim ricardo E.Perez Lothar A.Blatter Carl G.maki Department of Cell and molecular medicine Rush University Medical CenterChicagoIL 60612USA Department of molecular Biophysics and Physiology Rush University Medical CenterChicagoIL 60612USA

Tamoxifen(TAm)is the first-line endocrine therapy for estrogen receptor-positive(ER+)breast cancer(BC).However,acquired resistance occurs in∼50%***,although the PI3K/AKT/mTOR pathway is a viable target for treatment of endocrine therapy-refractory patients,complex signaling feedback loops exist,which can counter the effectiveness of inhibitors of this ***,we analyzed signaling pathways and metabolism in ER+mCF7 BC cell line and their TAm-resistant derivatives that are co-resistant to endoxifen using immunoblotting,quantitative polymerase chain reaction,and the Agilent Seahorse XF *** found that activation of AKT and the energy-sensing kinase AmPK was increased in TAm and endoxifen-resistant ***,ERRα/PGC-1βand their target genes mCAD and CPT-1 were increased and regulated by AmPK,which coincided with increased fatty acid oxidation(FAO)and autophagy in TAm-resistant *** of AKT feedback-activates AmPK and ERRα/PGC-1β-mCAD/CPT-1 with a consequent increase in FAO and autophagy that counters the therapeutic effect of endoxifen and AKT ***,our results indicate increased activation of AKT and AmPK with metabolic reprogramming and increased autophagy in TAm-resistant *** inhibition of AKT and FAO/autophagy is necessary to fully sensitize resistant cells to endoxifen.

关键词： endoxifen fatty acid oxidation autophagy AmPK AKT

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Experimental verification of ill-defined topologies and energy sinks in electromagnetic continua

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Advanced Photonics 2022年第3期4卷 97-104页

作者： David E.Fernandes ricardo A.m.Pereira Sylvain Lannebère Tiago A.morgado mário G.Silveirinha University of Coimbra Instituto de Telecomunicações and Department of Electrical EngineeringCoimbraPortugal University of Aveiro Instituto de TelecomunicaçõesDepartment of ElectronicsTelecommunications and InformaticsAveiroPortugal University of Lisbon Instituto Superior Técnico and Instituto de TelecomunicaçõesDepartment of Electrical EngineeringLisboaPortugal

.It is experimentally verified that nonreciprocal photonic systems with continuous translation symmetry may have an ill-defined *** topological classification of such systems is only feasible when the material response is regularized with a spatial-frequency *** experimentally demonstrate that adjoining a small air layer to the relevant material interface may effectively imitate an idealized spatial cutoff that suppresses the nonreciprocal response for short wavelengths and regularizes the ***,it is experimentally verified that nonreciprocal systems with an ill-defined topology may be used to abruptly halt the energy flow in a unidirectional waveguide due to the violation of the bulk-edge *** particular,we report the formation of an energy sink that absorbs the incoming electromagnetic waves with a large field enhancement at the singularity.

关键词： topological photonics nonreciprocity topological singularities bulk edge correspondence.

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p53 promotes AKT and SP1-dependent metabolism through the pentose phosphate pathway that inhibits apoptosis in response to Nutlin-3a

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Journal of molecular Cell Biology 2018年第4期10卷 331-340页

作者： Text Lei Duan ricardo E. Perez Ling Chen Lothar A. Blatter Carl G. maki Department of Cell & molecular medicine Rush University Medical Center Chicago IL 60612 USA Department of Laboratory medicine Shiyan Taihe Hospital College of Biomedical Engineering Hubei University of Medicine Shiyan 442000 China Department of Physiology & Biophysics Rush University Medical Center Chicago IL 60612 USA

Nutlin-3a is a mDm2 antagonist and preclinical drug that activates p53. Cells with mDm2 gene amplification are especially prone to Nutlin-3a-induced apoptosis, though the basis for this is unclear. Glucose metabolism can inhibit apoptosis in response to Nutlin-3a through mechanisms that are incompletely understood. Glucose metabolism through the pentose phosphate pathway （PPP） produces NADPH that can protect cells from potentially lethal reactive oxygen species （ROS）. We compared apoptosis and glucose metabolism in cancer cells with and without mDm2 gene amplification treated with Nutlin-3a. Apoptosis in mDm2-amplified cells was associated with a reduction in glycolysis and the PPP, reduced NADPH, increased ROS, and depletion of the transcription factor SP1, which normally promotes PPP gene expression. In contrast, glycolysis and the PPP were maintained or increased in mDm2 non-amplified cells treated with Nutlin-3a. This was dependent on p53-mediated AKT activation and was associated with maintenance of SP1 and continued expression of PPP genes. Knockdown or inhibition of AKT, SP1, or the PPP sensitized mDm2-non-amplified cells to apoptosis. The data indicate that p53 promotes AKT and SP1-dependent activation of the PPP that protects cells from Nutlin-3a-induced apoptosis. These findings provide insight into how glucose metabolism reduces Nutlin-3a-induced apoptosis, and also provide a mechanism for the heightened sensitivity of mDm2-amplified cells to apoptosis in response to Nutlin-3a.

关键词： Nutlin p53 mDm2 SP1 glycolysis pentose phosphate pathway

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A large epeiric methanogenic Bambuí sea in the core of Gondwana supercontinent?

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Geoscience Frontiers 2021年第1期12卷 203-218页

作者： Sergio Caetano-Filho Pierre Sansjofre magali Ader Gustavo m.Paula-Santos Cristian Guacaneme marly Babinski Carolina Bedoya-Rueda matheus Kuchenbecker Humberto L.S.Reis ricardo I.F.Trindade Universidade de Sao Paulo Instituto de GeocienciasRua do Lago562-Sao Paulo05508-080Brazil mNHN Sorbonne UniversiteCNRS UMR 7590Institut de Mineralogiede Physique des Materiaux et de Cosmochimie75005ParisFrance Universite de Paris Institut de Physique du Globe de ParisCNRSF-75005ParisFrance Universidade Estadual de Campinas Instituto de GeocienciasRua Carlos Gomes250-Campinas13083-855Brazil Universidade Federal dos Vales do Jequitinhonha e mucuri Instituto de Ciencia e TecnologiaLaboratorio de Estudos TectonicosRodovia MGT 367Km 583-Diamantina39100-000Brazil Universidade Federal de Ouro Preto Departamento de Geologia-Escola de MinasLaboratiorio de Modelagem TectonicaCampus Morro do Cruzeiro-Ouro Preto35400-000Brazil Universidade de Sao Paulo Instituto de AstronomiaGeofísica e Ciencias AtmosfericasRua do Matao1226-Sao Paulo05508-090Brazil

Carbon isotope compositions of both sedimentary carbonate and organic matter can be used as key proxies of the global carbon cycle and of its evolution through time,as long as they are acquired from waters where the dissolved inorganic carbon(DIC)is in isotope equilibrium with the atmospheric ***,in shallow water platforms and epeiric settings,the influence of local to regional parameters on carbon cycling may lead to DIG isotope variations unrelated to the global carbon *** may be especially true for the terminal Neoproterozoic,when Gondwana assembly isolated waters masses from the global ocean,and extreme positive and negative carbon isotope excursions are recorded,potentially decoupled from global *** improve our understanding on the type of information recorded by these excursions,we investigate the pairedδ^13Ccarb andδ^13Corg evolution for an increasingly restricted late Ediacaran-Cambrian foreland system in the West Gondwana interior:the basal Bambui *** succession represents a 1~(st)-order sedimentary sequence and records two majorδ^13Ccarb excursions in its two lowermost lower-rank *** basal cap carbonate interval at the base of the first sequence,deposited when the basin was connected to the ocean,hosts antithetical negative and positive excursions forδ^13Ccarb andδ^13Corg,respectively,resulting inΔ^13C values lower than 25‰.From the top of the basal sequence upwards,an extremely positiveδ^13Ccarb excursion is coupled toδ^13Corg,reaching values of+14‰and-14‰,*** positive excursion represents a remarkable basin-wide carbon isotope feature of the Bambui Group that occurs with only minor changes inΔ^13C values,suggesting change in the DIC isotope *** argue that this regional isotopic excursion is related to a disconnection between the intrabasinal and the global carbon *** extreme carbon isotope excursion may have been a product of a disequilibria between the basin DIC and atmospheric CO2

关键词： methanogenesis Ediacaran Cambrian Carbon isotopes Sao Francisco Basin Bambui Group

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Scarcity events analysis in adequacy studies using CN2 rule mining

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Energy and AI 2022年第2期8卷 116-123页

作者： Fabian Heymann ricardo Bessa mario Liebensteiner Konstantinos Parginos Juan Carlos martin Hinojar Pablo Duenas Center for Power and Energy Systems INESC TEC Porto Portugal School of Business Economics and Society Friedrich-Alexander-Universitat Erlangen-Nuremberg NurembergGermany System Development ENTSO-E Brussels Belgium mIT Energy Initiative massachusetts Institute of Technology Cambridge(mA) United States PERSEE Mines ParisTech

Dealing with scarcity events is nowadays gaining relevance in electricity market studies, as traditionally predictable generation and consumption patterns are fading. Policymakers and system planners use therefore adequacy studies to a) understand if the current market design will attract sufficient generation capacity to meet electricity demand in the future and b) to comprehend what drives system inadequacy or resource scarcity when future scenarios lack adequate capacity. This work addressed the latter and showcases a first in-its-kind rulebased methodology that filters scarcity events from a large set of electricity market simulations. In this proof-of-concept, a rule-mining algorithm is applied to outputs from ENTSO-E’s Pan-European electricity market model, which is run for 700 model scenarios, each covering 8760 time steps. The developed methodology shows how to unveil potential reasons behind scarcity events in an automated, interpretable, and scalable manner.

关键词： Electricity markets Data mining Security of supply Renewable energy Interpretability

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Estimation of Low Nutrients in Tomato Crops Through the Analysis of Leaf Images Using machine Learning

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Journal of Artificial Intelligence and Technology 2021年第2期1卷 131-137页

作者： Hiram Ponce Claudio Cevallos ricardo Espinosa Sebastián Gutiérrez Universidad Panamericana Facultad de IngenieríaAugusto Rodin 498Ciudad de México 03920México Universidad Panamericana Facultad de IngenieríaJosemaría Escriváde Balaguer 101Aguascalientes 20290México

Tomato crops are considered the most important agricultural products ***,the quality of tomatoes depends mainly on the nutrient *** inspection is made by farmers to anticipate the nutrient deficiency of the ***,precision agriculture has explored opportunities to automate nutrient level *** work has demonstrated that a convolutional neural network is able to estimate low nutrients in tomato plants using images of their ***,the performance of the convolutional neural network was not ***,this work proposes a novel convolutional neural network-based classifier,namely,CNN+AHN,for estimating low nutrients in tomato crops using an image of the tomato *** CNN+AHN incorporates a set of convolutional layers as the feature extraction part,and a supervised learning method called artificial hydrocarbon network as the dense *** combinations of the architecture of CNN+AHN were *** results showed that our best CNN+AHN classifier is able to estimate low nutrients in tomato plants with an accuracy of 95.57%and F1-score of 95.75%,outperforming the literature.

关键词： agriculture image processing deep learning computer vision color analysis

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Effects of combined pre- and post-natal protein deprivation on the myenteric plexus of the esophagus of weanling rats:A histochemical,quantitative and ultrastructural study

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World Journal of Gastroenterology 2007年第26期13卷 3598-3604页

作者： Edson A Liberti ricardo BV Fontes Verginia m Fuggi Laura Bm maifrino Romeu R Souza Autonomic Nervous System Laboratory (VQm) Department of AnatomyInstitute of Biomedical SciencesUniversity of So Paulo So PauloBrazil

AIm: To evaluate the effects of protein deprivation on the myenteric plexus of the esophagus of weanling rats. mETHODS: Pregnant female Wistar rats were divided into 2 groups: nourished (N),receiving normal diet,and undernourished (D),receiving a protein-deprived diet,which continued after birth. At twenty-one days of age,13 esophagi from each group were submitted to light microscopy and morphometrical analysis employing the NADH diaphorase,NADPH diaphorase and acetylcholinesterase techniques. Three other esophagi from each group were evaluated with transmission electron microscopy (TEm). RESULTS: In both the NADH- and the NADPH-reactive mounts,the neurons of the N mounts were more intensely stained,while in the D esophagi only the larger neurons were reactive. many myenteric neurons of N were intensely reactive for AChE activity but only a few neurons of D exhibited these aspects. Ultrastructural analysis revealed that the granular reticulum of N showed large numbers of ribosomes aligned on the outer surface of its regularly arranged membrane while the ribosomes of D were disposed in clusters. The chromatin was more homogeneously scattered inside the neuron nucleus of N as well as the granular component of the nucleolus was evidently more developed in this group. Statistically significant differences between N and D groups were detected in the total estimated number of neurons stained by the NADPH technique. CONCLUSION: The morphological and quantitative data shows that feeding with protein-deprived diet in 21-d old rats induces a delay in the development of the myenteric neurons of the esophagus.

关键词： Enteric nervous system myenteric plexus Nutrition microscopy Electron Transmission Esopha-gus Rat Wistar

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