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1.
Landgrave-Barbosa Fernando Marmolejo-Valencia Andrés F. Baray-Calderón Alejandro Hu Hailin Aguilar-Cordero Julio César Amador-Bedolla Carlos Ugalde-Saldivar Víctor M. 《Journal of Solid State Electrochemistry》2022,26(3):649-661
Journal of Solid State Electrochemistry - A study of poly(3-hexylthiophene) (P3HT) thin films by spin-coating process, deposited on conducting glass substrates of fluorine-doped tin oxide (FTO), is... 相似文献
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Hctor Solís-Chagoyn Aline Domínguez-Alonso Marcela Valds-Tovar Jesús Argueta Zuly A. Snchez-Florentino Eduardo Calixto Gloria Benítez-King 《Molecules (Basel, Switzerland)》2020,25(23)
The pro-oxidant compound okadaic acid (OKA) mimics alterations found in Alzheimer’s disease (AD) as oxidative stress and tau hyperphosphorylation, leading to neurodegeneration and cognitive decline. Although loss of dendrite complexity occurs in AD, the study of this post-synaptic domain in chemical-induced models remains unexplored. Moreover, there is a growing expectation for therapeutic adjuvants to counteract these brain dysfunctions. Melatonin, a free-radical scavenger, inhibits tau hyperphosphorylation, modulates phosphatases, and strengthens dendritic arbors. Thus, we determined if OKA alters the dendritic arbors of hilar hippocampal neurons and whether melatonin prevents, counteracts, or reverses these damages. Rat organotypic cultures were incubated with vehicle, OKA, melatonin, and combined treatments with melatonin either before, simultaneously, or after OKA. DNA breaks were assessed by TUNEL assay and nuclei were counterstained with DAPI. Additionally, MAP2 was immunostained to assess the dendritic arbor properties by the Sholl method. In hippocampal hilus, OKA increased DNA fragmentation and reduced the number of MAP2(+) cells, whereas melatonin protected against oxidation and apoptosis. Additionally, OKA decreased the dendritic arbor complexity and melatonin not only counteracted, but also prevented and reversed the dendritic arbor retraction, highlighting its role in post-synaptic domain integrity preservation against neurodegenerative events in hippocampal neurons. 相似文献
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Dr. Marzia Dell'Aera Dr. Filippo Maria Perna Dr. Paola Vitale Dr. Angela Altomare Prof. Alessandro Palmieri Dr. Lewis C. H. Maddock Leonie J. Bole Dr. Alan R. Kennedy Prof. Eva Hevia Prof. Vito Capriati 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(40):8742-8748
We report the first transition metal catalyst- and ligand-free conjugate addition of lithium tetraorganozincates (R4ZnLi2) to nitroolefins. Displaying enhanced nucleophilicity combined with unique chemoselectivity and functional group tolerance, homoleptic aliphatic and aromatic R4ZnLi2 provide access to valuable nitroalkanes in up to 98 % yield under mild conditions (0 °C) and short reaction time (30 min). This is particularly remarkable when employing β-nitroacrylates and β-nitroenones, where despite the presence of other electrophilic groups, selective 1,4 addition to the C=C is preferred. Structural and spectroscopic studies confirmed the formation of tetraorganozincate species in solution, the nature of which has been a long debated issue, and allowed to unveil the key role played by donor additives on the aggregation and structure of these reagents. Thus, while chelating N,N,N’,N’-tetramethylethylenediamine (TMEDA) and (R,R)-N,N,N’,N’-tetramethyl-1,2-diaminocyclohexane (TMCDA) favour the formation of contacted-ion pair zincates, macrocyclic Lewis donor 12-crown-4 triggers an immediate disproportionation process of Et4ZnLi2 into equimolar amounts of solvent-separated Et3ZnLi and EtLi. 相似文献
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Víctor Leiva 《商业与工业应用随机模型》2019,35(1):133-137
Sam C. Saunders, the son of Elizabeth Cundiff and Winston E. Saunders, was born in Richland, OR, on February 24, 1931. The family moved to La Grande, OR, in 1944, where Sam completed high school and two years at Eastern Oregon College. He then received the BSc degree in Mathematics from the University of Oregon, Eugene, OR, in 1952, and he attended the University of Washington, Seattle, WA, receiving a PhD degree under Z. W. Birnbaum. After graduating, he accepted employment at the Boeing Company in its Mathematical Services Unit and, in 1972, a position as a Full Professor at Washington State University, Pullman, WA, from which he retired in 1996. 相似文献
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A method to generate NOON states with three photons by injecting photons in an array of three waveguides is presented. Conditional measurements project the wave function in a given (desired) state. In passing, it is shown how the array of three waveguides, that effectively reproduces the interaction of three fields, may be reduced to the interaction of two fields. 相似文献
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Maldonado-Bustamante Sara Roxana Mondaca-Fernndez Iram Gortares-Moroyoqui Pablo Berg Alex Balderas-Corts Jos de Jess Meza-Montenegro Mara Mercedes Brown-Bojrquez Francisco Arvayo-Enrquez Hctor 《Cellulose (London, England)》2022,29(13):7151-7161
Cellulose - The present study investigates the organosolv treatment of wheat straw, for the optimization of cellulose delignification, which will serve as raw material for the paper industry. The... 相似文献
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Electronic Structure Modulation in an Exceptionally Stable Non‐Heme Nitrosyl Iron(II) Spin‐Crossover Complex 下载免费PDF全文
Lucía Piñeiro‐López Dr. Norma Ortega‐Villar Prof. Dr. M. Carmen Muñoz Dr. Gábor Molnár Dr. Jordi Cirera Prof. Dr. Rafael Moreno‐Esparza Prof. Dr. Víctor M. Ugalde‐Saldívar Dr. Azzedine Bousseksou Prof. Dr. Eliseo Ruiz Prof. Dr. José A. Real 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(36):12741-12751
The highly stable nitrosyl iron(II) mononuclear complex [Fe(bztpen)(NO)](PF6)2 (bztpen=N‐benzyl‐N,N′,N′‐tris(2‐pyridylmethyl)ethylenediamine) displays an S=1/2?S=3/2 spin crossover (SCO) behavior (T1/2=370 K, ΔH=12.48 kJ mol?1, ΔS=33 J K?1 mol?1) stemming from strong magnetic coupling between the NO radical (S=1/2) and thermally interconverted (S=0?S=2) ferrous spin states. The crystal structure of this robust complex has been investigated in the temperature range 120–420 K affording a detailed picture of how the electronic distribution of the t2g–eg orbitals modulates the structure of the {FeNO}7 bond, providing valuable magneto–structural and spectroscopic correlations and DFT analysis. 相似文献
10.
We introduce themulti-poly-Bernoulli numbers and polynomialswith a q parameter, which are generalizations of the poly-Bernoulli numbers and polynomials with a q parameter, respectively.We give several combinatorial identities and properties of these new numbers and polynomials. 相似文献