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121.
122.
Luan Amrico-Da-Silva Javiera Aguilera Oscar Quinteros-Waltemath Pablo Snchez-Aguilera Javier Russell Cynthia Cadagan Roberto Meneses-Valds Gina Snchez Manuel Estrada Gonzalo Jorquera Genaro Barrientos Paola Llanos 《International journal of molecular sciences》2021,22(19)
Low-grade chronic inflammation plays a pivotal role in the pathogenesis of insulin resistance (IR), and skeletal muscle has a central role in this condition. NLRP3 inflammasome activation pathways promote low-grade chronic inflammation in several tissues. However, a direct link between IR and NLRP3 inflammasome activation in skeletal muscle has not been reported. Here, we evaluated the NLRP3 inflammasome components and their role in GLUT4 translocation impairment in skeletal muscle during IR. Male C57BL/6J mice were fed with a normal control diet (NCD) or high-fat diet (HFD) for 8 weeks. The protein levels of NLRP3, ASC, caspase-1, gasdermin-D (GSDMD), and interleukin (IL)-1β were measured in both homogenized and isolated fibers from the flexor digitorum brevis (FDB) or soleus muscle. GLUT4 translocation was determined through GLUT4myc-eGFP electroporation of the FBD muscle. Our results, obtained using immunofluorescence, showed that adult skeletal muscle expresses the inflammasome components. In the FDB and soleus muscles, homogenates from HFD-fed mice, we found increased protein levels of NLRP3 and ASC, higher activation of caspase-1, and elevated IL-1β in its mature form, compared to NCD-fed mice. Moreover, GSDMD, a protein that mediates IL-1β secretion, was found to be increased in HFD-fed-mice muscles. Interestingly, MCC950, a specific pharmacological NLRP3 inflammasome inhibitor, promoted GLUT4 translocation in fibers isolated from the FDB muscle of NCD- and HFD-fed mice. In conclusion, we found increased NLRP3 inflammasome components in adult skeletal muscle of obese insulin-resistant animals, which might contribute to the low-grade chronic metabolic inflammation of skeletal muscle and IR development. 相似文献
123.
Jorge Teniente Ramón Gonzalo Carlos del Rio Javier Martí-Canales Mario Sorolla Angela Fernández Konstantin M. Likin Romualdo Martín 《Journal of Infrared, Millimeter and Terahertz Waves》1999,20(10):1757-1767
This paper presents the design and characterisation of a millimetre-wave corrugated horn antenna to perform low power measurements of the main parameters of the quasioptical transmission lines of the Electron Cyclotron Resonance Heating (ECRH) at TJ-II stellerator experiment working in Madrid (E). The antenna generates a practically pure Gaussian Beam at 53.2 GHz that simulates the stellerator gyrotron output beam. Simulations of the designed corrugated horn, by using a specially developed computer code, are presented. The far field radiation pattern of the constructed prototype was measured at the ESTEC Compact Antenna Test Range (CATR). The measurement results are in excellent agreement with those obtained from simulations. 相似文献
124.
Marina García‐Rosas Arturo Bello‐Prez Hernani Yee‐Madeira Gonzalo Ramos Areli Flores‐Morales Rosalva Mora‐Escobedo 《Starch - St?rke》2009,61(7):414-421
Storage of maize products such as tortillas may cause starch retrogradation and lead to resistant starch (RS) formation. This study was carried out to determine if storage of maize tortillas under refrigerated conditions enhanced RS content and/or modified RS structure. Improved Costeño variety maize grain was nixtamalized and processed into tortillas which were stored for five and ten days at 5°C. Total resistant starch (TRS) and retrograded resistant starch (RRS or RS3) contents were determined on raw and nixtamalized maize grain and tortillas stored for zero, five and ten days. Differential scanning calorimetry (DSC), X‐ray diffraction (XRD) and near‐infrared (NIR) spectroscopy were use to evaluate structural changes in retrograded resistant starch isolated from each sample type. Total starch content was 67 ± 1.5% for all samples, TRS ranged from 3.3% in the raw grain at 7.2% in tortillas stored for ten days, while RRS starch content ranged from 0% in the raw grain to 3.2% in tortillas stored for ten days. DSC showed endothermic transitions corresponding to amylopectin and amylose retrogradation, at 31.9 and 139.7°C in RRS from tortillas stored for five days, and at 47.9 and 146°C in RRS from tortillas stored for ten days. These values agreed with the higher total RS content recorded after prolonged storage. XRD revealed a starch crystallinity of 13.7% in tortillas stored for five days and 15.3% in those stored for ten days. NIR spectroscopy analysis showed evidence of structural changes in polymeric order that were more pronounced in RRS of tortillas stored for ten days, due to increase in crystalline region. 相似文献
125.
Cndida Lorenzo Teresa Garde-Cerdn Miguel A. Pedroza Gonzalo L. Alonso M. Rosario Salinas 《Food research international (Ottawa, Ont.)》2009,42(9):1281-1286
The purpose of this work was to study the possibility of determination of fermentative volatile compounds in aged red wines using NIR spectroscopy. To achieve this, 240 wines belonging to different geographic zones and elaborated with one or two varieties were analyzed. The volatile compounds were quantified by SBSE-GC–MS. Spectra obtained by NIR were co-related with these values using partial least square (PLS) regression. Calibration and validation statistics showed the quality of the model, after all when is done separately for each of the four geographic zones, and in the case of wines elaborated with two varieties. Consequently, near infrared spectroscopy can be used as an easy and rapid tool to determine fermentative volatile compounds in aged red wines. 相似文献
126.
Application of RFID technologies in the temperature mapping of the pineapple supply chain 总被引:2,自引:0,他引:2
Cecilia Amador Jean-Pierre Emond Maria Cecilia do Nascimento Nunes 《Sensing and Instrumentation for Food Quality and Safety》2009,3(1):26-33
Current temperature tracking systems lack the convenience and accuracy demanded by the real conditions of a fast-paced produce
supply chain. In recent years RFID technology has been suggested to be an enhanced method for temperature tracking because
of its many benefits, such as using little instrumentation, offering the quick readings necessary for real-time decision making,
and allowing the capture of long-duration temperature profiles. However its limitation lies in that probeless systems fail
to provide accurate temperature readings in some of the critical points of the pallet and the load. The objective of this
work was to study the use of RFID in temperature monitoring by comparing the performance of RFID temperature tags versus conventional
temperature tracking methods, as well as RFID temperature tags with probe versus RFID temperature tags without probes and
their utilization along the supply chain. Therefore, the temperature mapping of a shipping trial comprising pallets of crownless
pineapples instrumented using different RFID temperature dataloggers and traditional temperature dataloggers and packed in
two kinds of packages (corrugated boxes and reusable plastic containers) inside a container was performed. The results showed
that RFID temperature tags are analogous with regards to accuracy to the conventional methods, but have a superior performance
because they allow quick instrumentation and data recovery, and the possibility of accessing the sensor program and data at
any point of the supply chain without line of sight. In addition, the use of RFID tags with probe was justified by its role
in determining the efficiency of the pre-cooling operations and low temperature abuse tracking during transportation and refrigerated
storage; while the RFID tags without probe proved useful for high temperature abuse monitoring during transportation and refrigerated
storage. The creation of a RFID sensor with a probe, able to record both ambient and pulp temperatures simultaneously is suggested.
Presented at Food Processing Automation Conference, American Society of Agricultural and Biological Engineering (ASABE), Providence,
RI, USA, June 28–29 2008. 相似文献
127.
Digital in-line holographic microscopy (DIHM) using point sources has been shown to be a versatile technique, especially for three-dimensional tracking of particles or microorganisms. However, the spherical source wave is altered when measurements are performed through layers with different refractive indices, such as water cuvettes. The situations where a layer of medium with a refractive index different than that of the predominant surrounding propagation medium (usually air) is situated behind or in front of the plane to be reconstructed are analyzed in detail, and a general approach for reconstruction under such circumstances is developed. The proposed refractive index correction is tested experimentally and compared to conventional reconstruction algorithms. Using 3D traces of swimming algal spores, the influence on the velocity calculation is also shown. 相似文献
128.
Gonzalo del Coso Carlos del CañizoAntonio Luque 《Solar Energy Materials & Solar Cells》2011,95(4):1042-1049
This work aims at understanding the energy loss in the polysilicon deposition reactor during the production of solar grade silicon. The radiative heat transfer between the polysilicon rods and the reactor wall in the so-called Siemens reactor is studied in detail in this paper. First, the most commonly used reactor configuration, 36 rods in three rings, is explained, detailing the particular radiation transfer of each rod toward the wall. Based on this analysis, some proposals for diminishing the energy loss are proposed: enlarge the reactor capacity, improve the properties of the reactor wall and introduce thermal shields. The impact of each proposal on the energy savings is quantified. If the reactor capacity is enlarged from 36 to 60 rods, the energy savings would be around 11 kWh per kg of polysilicon produced (kWh kg−1). Increasing the reflectivity of the wall, the savings would be around 17 kWh kg−1. And finally, the potential for cost reduction because of the introduction of thermal shields would be 20 kWh kg−1. 相似文献
129.
Molet Mika?l; Urcelay Gonzalo P.; Miguez Gonzalo; Miller Ralph R. 《Canadian Metallurgical Quarterly》2010,36(1):126
Three conditioned lick suppression experiments with rats examined the role of the context in the selection and integration of independently acquired interval relationships. In Experiment 1, rats were exposed to separate conditioned stimuli 1 and 2 (CS1–CS2) pairings with 2 different interval relationships, each in its own distinctive context, X or Y. The resultant integration was determined by the training context (X or Y) in which unconditioned stimulus (US)–CS2 backward pairings occurred, as assessed in a third neutral context (Z). In Experiment 2, rats experienced CS1–CS2 pairings with 2 different interval relationships as in Experiment 1, and then received US–CS2 pairings in both contexts X and Y. The testing context (i.e., X or Y) determined the resultant integration. In Experiment 3, rats were exposed to CS1–CS2 pairings in 2 different interval relationships each in different phases (i.e., Phases 1 and 2), and then in Phase 3 received US–CS2 pairings. The temporal context of testing (i.e., short or long retention interval) determined the resultant integration. Thus, both physical and temporal context can be used to disambiguate conflicting temporal information. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
130.
High temperature tribological characterisation of TiAlSiN coatings produced by cathodic arc evaporation 总被引:2,自引:0,他引:2
Gonzalo G. Fuentes Eluxka Almandoz Rosario Martínez Jaume Caro 《Surface & coatings technology》2010,205(5):1368-1373
This study reports on the wear properties at medium-high temperatures of TiAlSiN films deposited by cathodic arc evaporation on hot work steel substrates. The chemical composition and microstructure of the coatings were characterised by glow discharge optical emission spectroscopy, scanning electron microscopy and X-ray diffraction. The mechanical properties, i.e. hardness and elastic modulus were evaluated by nanoindentation, and the adhesion of the coatings was tested by scratch tests. Coatings with stoichiometries of Ti0.31Al0.1Si0.06N0.53 and Ti0.23Al0.12Si0.09N0.55 exhibit microstructures consisting of solid solutions of (Ti,Al,Si)N, where Al and Si replace Ti atoms. These films show high hardness and good adhesion strength to the hot work steels. Conversely, coatings with a stoichiometry of Ti0.09Al0.34Si0.02N0.55 show a wurtzite-like microstructure, low hardness and poor adhesion strength.The wear rates of the coatings were investigated by ball-on-disc experiments at room temperature, 200 °C, 400 °C and 600 °C, using alumina balls as counter surfaces. At room temperature, the films show wear rates of the same order of magnitude of TiN and TiAlN coatings. On the other hand, the wear rates of solid solution (Ti,Al,Si)N coatings measured at 200, and 400 °C are one order of magnitude smaller than those measured at room temperature due to the formation of oxide-containing tribofilms on the wear tracks. At 600 °C the wear rates increase but still keep smaller than those measured at room temperature, although this effect can be influenced by the softening of the steel substrates by over-tempering. EDS analyses revealed that, between 200 °C and 400 °C, the oxidation of the coating occurs only at the contact zone between the film and the counterpart body due to the sliding process. 相似文献