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61.
Gabriela Ben-Melech Stan Kapil Dhaka Maytal Caspary Toroker 《Israel journal of chemistry》2020,60(8-9):888-896
Two-dimensional transistors are promising candidates for the next generation of nanoscale devices. Like the other alternatives, they also encounter problems such as instability under standard condition (STP), low channel mobility, small band gaps, and difficulty to integrate metal contacts. The latter poses a great challenge since metal/semiconductor interface significantly affects the transistor‘s performance. Some of these obstacles can be solved by using two-dimensional transition metal di-chalcogenides (TMDC) materials. In this study, we performed charge transport calculation based on density functional theory (DFT) followed by wave dynamics to evaluate the performance of six two-dimensional TMDC metal/semiconductor/metal systems. Each semiconductor monolayer was laterally connected, at both ends to metal contacts consisting of VS2 or FeS2 monolayers. We found that charge transport was more efficient in systems containing a CrS2 semiconductor monolayer compared to systems with MoS2 or WS2 as the semiconductor monolayer. The electronic characterization of the monolayer TMDC materials by DFT estimates well the trend in charge transport efficiency calculated using wave packet dynamics. 相似文献
62.
Miguel Olvera-Sosa Antonio Guerra-Contreras Cesar F. A. Gómez-Durán Raúl González-García Gabriela Palestino 《应用聚合物科学杂志》2020,137(8):48403
The swelling behavior of poly(acrylic acid-co-itaconic acid)/NaOH hydrogel as well as its ability for iron and copper rust removal was studied and established for the first time. Through an experimental design, the influence of the synthesis parameters on hydrogel response was determined. It was found that pH-responsiveness dependence of hydrogel determines its application. In alkaline media, the hydrogel acted as superabsorbent, while in acidic, the most outstanding property was its pickling capability that allowed to clean carbon steel and copper metallic surfaces. Infrared, thermogravimetry, and scanning electron microscopy were performed to determine copolymer formation, thermal properties, and morphology. Metallic crystallographic phases formed during the corrosion processes were determined by X-ray diffractometer. Hydrogel adhesiveness followed by diffusion and dissolution of metal oxides species was identified as the main steps in the rust removal mechanism. This method offers a new, environmentally friendly perspective to eliminate corrosion from metallic surfaces compared with traditional strategies. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48403. 相似文献
63.
Nina Kunov Henrieta Havalov Gabriela Ondrovi
ov Barbora Stojkovi
ov Jacob A. Bauer Vladena Bauerov-Hlinkov Vladimir Pevala Eva Kutejov 《International journal of molecular sciences》2022,23(3)
Mitochondrial proteins are encoded by both nuclear and mitochondrial DNA. While some of the essential subunits of the oxidative phosphorylation (OXPHOS) complexes responsible for cellular ATP production are synthesized directly in the mitochondria, most mitochondrial proteins are first translated in the cytosol and then imported into the organelle using a sophisticated transport system. These proteins are directed mainly by targeting presequences at their N-termini. These presequences need to be cleaved to allow the proper folding and assembly of the pre-proteins into functional protein complexes. In the mitochondria, the presequences are removed by several processing peptidases, including the mitochondrial processing peptidase (MPP), the inner membrane processing peptidase (IMP), the inter-membrane processing peptidase (MIP), and the mitochondrial rhomboid protease (Pcp1/PARL). Their proper functioning is essential for mitochondrial homeostasis as the disruption of any of them is lethal in yeast and severely impacts the lifespan and survival in humans. In this review, we focus on characterizing the structure, function, and substrate specificities of mitochondrial processing peptidases, as well as the connection of their malfunctions to severe human diseases. 相似文献
64.
Gabriela Antonio-Andres Gustavo U. Martinez-Ruiz Mario Morales-Martinez Elva Jimnez-Hernandez Estefany Martinez-Torres Tania V. Lopez-Perez Laura A. Estrada-Abreo Genaro Patino-Lopez Sergio Juarez-Mendez Víctor M. Davila-Borja Sara Huerta-Yepez 《International journal of molecular sciences》2022,23(3)
65.
Damian Jozef Flis Emilia Gabriela Bialobrodzka Ewa Aleksandra Rodziewicz-Flis Zbigniew Jost Andzelika Borkowska Wieslaw Ziolkowski Jan Jacek Kaczor 《International journal of molecular sciences》2022,23(2)
This study investigates the effect of Dexamethasone (Dex) treatment on blood and skeletal muscle metabolites level and skeletal muscle activity of enzymes related to energy metabolism after long-duration swimming. To evaluate whether Dex treatment, swimming, and combining these factors act on analyzed data, rats were randomly divided into four groups: saline treatment non-exercise and exercise and Dex treatment non-exercised and exercised. Animals in both exercised groups underwent long-lasting swimming. The concentration of lipids metabolites, glucose, and lactate were measured in skeletal muscles and blood according to standard colorimetric and fluorimetric methods. Also, activities of enzymes related to aerobic and anaerobic metabolism were measured in skeletal muscles. The results indicated that Dex treatment induced body mass loss and increased lipid metabolites in the rats’ blood but did not alter these changes in skeletal muscles. Interestingly, prolonged swimming applied after 9 days of Dex treatment significantly intensified changes induced by Dex; however, there was no difference in skeletal muscle enzymatic activities. This study shows for the first time the cumulative effect of exercise and Dex on selected elements of lipid metabolism, which seems to be essential for the patient’s health due to the common use of glucocorticoids like Dex. 相似文献
66.
67.
Nicoleta Stănciuc Iuliana Aprodu Gabriela Râpeanu Gabriela Bahrim 《European Food Research and Technology》2013,236(2):257-266
Bovine α-lactalbumin (α-LA) is able to interact with fatty acids, resulting in structural changes that are potentially responsible for the HAMLET/BAMLET role. Different states of α-LA induced by pH, temperature and fatty acid binding have been examined. Evidences of the structural changes of α-LA in molten globule and native states in correlation with oleic acid (OA) binding are shown using fluorescence spectroscopy and in silico approach. In addition, the α-LA was subjected to automated docking analysis, to better understand the interaction with oleic acid, using the PatchDock algorithm. The experimental results demonstrate a more flexible conformation of the protein at pH 2.5 when compared to neutral pH, thus facilitating the oleic acid binding to α-LA. The quenching experiments indicate the remarkable increase in the content of molten globule state at pH 2.5 and a more compact and rigid structure for α-LA–OA complexes at pH 7.0. The docking results are consistent with the experimental data concerning the thermal stability of the α-LA–OA complex. α-LA in different conformations/complexes was sensitive to pH and temperature. Several different molecular species induced by pH, heat treatment and oleic acid binding were suggested. The structure of the protein was more flexible at acidic pH, therefore favoring the hydrophobic exposure. 相似文献
68.
This study aimed to compare Petrifilm Aerobic Count (AC) plates and the conventional pour plate methodology using de Mann-Rogosa-Sharpe (MRS), Kang-Fung (KF) and Kang-Fung-Sol (KFS) culture media for screening and enumeration of lactic acid bacteria (LAB) in milk. Suspensions of 10 LAB species in reconstituted powder skim milk and 30 raw milk samples, without experimental inoculation, were tested. For selective enumeration, all samples were previously diluted in MRS, KF and KFS broths and then plated in Petrifilm AC and conventional pour plate methodology, using the same culture media with added agar. All plates were incubated at 37 degrees C for 48 h in anaerobic conditions. Differences in the counts were observed only for raw milk samples using KFS in conventional methodology, when compared with the counts obtained from MRS and KF (P0.05). The results showed excellent correlation indexes between both methodologies using the three culture media for LAB suspensions (r=0.97 for MRS, KF and KFS). For raw milk samples, the correlation indexes were excellent (r=0.97, for MRS) and good (r=0.84 for KF, and r=0.82 for KFS), showing some interference in Petrifilm AC when supplements were added, especially lactic acid. These results indicate the possibility of using Petrifilm AC plates for enumeration of LAB in milk, even with the use of selective supplements. 相似文献
69.
Paola Roccia Pablo D. Ribotta Cristina Ferrero Gabriela T. Pérez Alberto E. León 《Food and Bioprocess Technology》2012,5(4):1255-1264
High levels of soy flour added to wheat bread produce negative effects on gluten network formation, dough properties, and
on bread final quality. The objective of this study was to assess the influence of three enzymes, transglutaminase (TG), glucose
oxidase (GOX), and endoxylanase (XYL), on dough properties and final quality of high-protein breads. The addition of TG and
GOX increased the mixing stability and maximum resistance of dough, decreased its extensibility, and produced stronger and
more consistent dough samples. XYL incorporation produced opposite results. XYL addition and the lowest GOX dose increased
bread volume significantly and decreased initial crumb firmness, while high doses of TG (0.3%) produced detrimental effects
on bread volume and crumb firmness. In conclusion, XYL and GOX 0.001% addition improved the final quality of soy-fortified
breads, but XYL was the best additive to improve dough properties, bread volume, and quality. 相似文献
70.
Daniel Alberto Sánchez Gabriela Marta Tonetto María Luján Ferreira 《Journal of the American Oil Chemists' Society》2014,91(2):261-270
New avenues to add value to glycerol are currently being explored. One of them is the synthesis of structured lipids through glycerol esterification. In this work we have analyzed the recovery and purification of dicaprin obtained by esterification of glycerol with capric acid (C) in heptane, mediated by Lipozyme RM IM. This is an intermediate step to obtain lipids MLM. In the first stage, the diglyceride synthesis MGM (being G a central HC–OH) was carried out. When M = C, the diglyceride is CGC. Recovery of the diglyceride CGC is required to carry out the esterification of the sn-2 position with palmitic acid (P), thus obtaining the triglyceride CPC. Different solvents were evaluated using Ecofac 1.0 (a molecular design software solvent) through a theoretical approach to explore the best solvents for the acylglycerides separation. Then, the performance of the selected solvents to separate dicaprin from mono and tricaprin was experimentally studied in a liquid–liquid extraction process. Previously, the remaining fatty acid had been neutralized. With liquid–liquid extraction in three simple steps, using ethanol/water, 94 % of the dicaprin obtained by enzymatic esterification was recovered with a purity of 89 % (wt%). It was also possible to obtain dicaprin with a purity of 97 % but with a yield of 56 %. 相似文献