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901.
Christian Battaglia Gustavo F. Vilella Ana P. S. Bernardo Carolina L. Gomes Adriele G. Biase Tiago Z. Albertini Sergio B. Pflanzer 《Journal of texture studies》2020,51(2):252-262
Slice shear force (SSF) and laser diffraction, considered faster methodologies, for measuring beef instrumental tenderness and sarcomere length, were compared with reference methodologies Warner–Bratzler shear force (WBSF) and phase contrast microscopy. Striploin samples (n = 74) were analyzed for pH, sarcomere length, instrumental tenderness, myofibrillar fragmentation index, and sensorial tenderness. Pearson's correlation measured the association of meat evaluation methods with residual analysis of the multivariate analysis of variance model. The n-dimensional profile to evaluated methods was presented by biplot to identify the behavior of the correlation between the methods (variables). There was moderate correlation between SSF and WBSF (r = .63; p < .01) and both presented moderate correlation with sensorial tenderness (r = − .62 and −.55, to SSF and WBSF, respectively; p < .01). However, WBSF was more efficient to classify samples as tender (68%) than SSF (47%), comparing with sensorial tenderness (80%). There was a moderate correlation for laser and microscopy for sarcomere length (r = .57; p < .01). Sarcomeres were shorter when measured by laser than microscopy. Either with low correlation coefficients, sarcomere measured by laser (r = .29; p < .05) presented higher correlation with sensorial tenderness than with microscopy (r = .22; p < .10). Results highlighted that SSF was faster and easier to run, while WBSF was more appropriate to classify samples by sensorial tenderness grades. Laser diffraction is more suitable to explain effects on tenderness; however, microscopy revealed results of sarcomere length that were more realistic, once laser can underestimate sarcomeres. 相似文献
902.
Atacy Maciel de Melo Cavalcante Anely Maciel de Melo Francisco Lucas Chaves Almeida Natasha Carolina Melo Diniz Laís Costa Luna Gledson Firmino Gonçalves da Silva Edilayane da Nóbrega Santos Thamyres Cesar de Albuquerque Sousa Neila Lidiany Ribeiro Osvaldo Soares da Silva 《Journal of Food Processing and Preservation》2022,46(3):e16377
903.
Silva KT Abreu F Almeida FP Keim CN Farina M Lins U 《Microscopy research and technique》2007,70(1):10-17
Magnetotactic bacteria orient and migrate along geomagnetic field lines. Each cell contains membrane-enclosed, nano-scale, iron-mineral particles called magnetosomes that cause alignment of the cell in the geomagnetic field as the bacteria swim propelled by flagella. In this work we studied the ultrastructure of the flagellar apparatus in many-celled magnetotactic prokaryotes (MMP) that consist of several Gram-negative cells arranged radially around an acellular compartment. Flagella covered the organism surface, and were observed exclusively at the portion of each cell that faced the environment. The flagella were helical tubes never as long as a complete turn of the helix. Flagellar filaments varied in length from 0.9 to 3.8 micro m (average 2.4 +/- 0.5 micro m, n = 150) and in width from 12.0 to 19.5 nm (average 15.9 +/- 1.4 nm, n = 52), which is different from previous reports for similar microorganisms. At the base of the flagella, a curved hook structure slightly thicker than the flagellar filaments was observed. In freeze-fractured samples, macromolecular complexes about 50 nm in diameter, which possibly corresponded to part of the flagella basal body, were observed in both the P-face of the cytoplasmic membrane and the E-face of the outer membrane. Transmission electron microscopy showed that magnetosomes occurred in planar groups in the cytoplasm close and parallel to the organism surface. A striated structure, which could be involved in maintaining magnetosomes fixed in the cell, was usually observed running along magnetosome chains. The coordinated movement of the MMP depends on the interaction between the flagella of each cell with the flagella of adjacent cells of the microorganism. 相似文献
904.
905.
J. Jerald P. Asokan R. Saravanan A. Delphin Carolina Rani 《The International Journal of Advanced Manufacturing Technology》2006,29(5):584-589
Automated Guided Vehicles (AGVs) are among various advanced material handling techniques that are finding increasing applications
today. They can be interfaced to various other production and storage equipment and controlled through an intelligent computer
control system. Both the scheduling of operations on machine centers as well as the scheduling of AGVs are essential factors
contributing to the efficiency of the overall flexible manufacturing system (FMS). An increase in the performance of the FMS
under consideration would be expected as a result of making the scheduling of AGVs an integral part of the overall scheduling
activity. In this paper, simultaneous scheduling of parts and AGVs is done for a particular type of FMS environment by using
a non-traditional optimization technique called the adaptive genetic algorithm (AGA). The problem considered here is a large
variety problem (16 machines and 43 parts) and combined objective function (minimizing penalty cost and minimizing machine
idle time). If the parts and AGVs are properly scheduled, then the idle time of the machining center can be minimized; as
such, their utilization can be maximized. Minimizing the penalty cost for not meeting the delivery date is also considered
in this work. Two contradictory objectives are to be achieved simultaneously by scheduling parts and AGVs using the adaptive
genetic algorithm. The results are compared to those obtained by conventional genetic algorithm. 相似文献
906.
Compositional effects on the crosslink density of Ca–(Mg)–(Y)–Si–Al–oxyfluoronitride glasses 下载免费PDF全文
Carolina Clausell Antonio Barba Juan Carlos Jarque Ángel R. García‐Bellés Michael J. Pomeroy Stuart Hampshire 《Journal of the American Ceramic Society》2018,101(1):189-200
The effects of fluorine and nitrogen substitution for oxygen in aluminosilicate glasses, effectively oxyfluoronitride (OFN) glasses, modified by calcium, calcium–yttrium or calcium–magnesium on thermal and physical/mechanical properties have been compared. Thus, 42 glasses in the Ca–(Mg)–(Y)–Si–Al–O–(N)–(F) system have been prepared and characterized with respect to density (ρ), molar volume (MV), compactness (C), free volume (FV), glass transition temperatures measured by DTA (Tg,DTA) and dilatometry (Tg,dil), dilatometric softening point (TDS), microhardness (μHv) and Young's modulus (E). Gradients of property variation with nitrogen or fluorine substitutions for oxygen are similar for all three different oxyfluoronitride glass systems and are comparable with those reported for other OFN glasses, again indicating independent and additive effects of nitrogen and fluorine. In attempting to further understand how fluorine affects the cross‐link density (CLD) in OFN glasses, it becomes apparent that it is necessary to allow for a greater contribution by aluminum in a modifier role as fluorine content is increased. This modified calculation of CLD values results in good linear fits between Tg and CLD values. This analysis clearly demonstrates and endorses the concepts that thermal properties are related to CLD while physical/mechanical properties are dependent on glass compactness. 相似文献
907.
Florian Mann Sohini Vanjari Neil Rosser Sandra Mann Kanchon K. Dasmahapatra Chris Corbin Mauricio Linares Carolina Pardo-Diaz Camilo Salazar Chris Jiggins Stefan Schulz 《Journal of chemical ecology》2017,43(9):843-857
Neotropical Heliconius butterflies are members of various mimicry rings characterized by diverse colour patterns. In the present study we investigated whether a similar diversity is observed in the chemistry of volatile compounds present in male wing androconia. Recent research has shown that these androconia are used during courting of females. Three to five wild-caught male Heliconius individuals of 17 species and subspecies were analyzed by GC/MS. Most of the identified compounds originate from common fatty acids precursors, including aldehydes, alcohols, acetates or esters preferentially with a C18 and C20 chain, together with some alkanes. The compounds occurred in species-specific mixtures or signatures. For example, octadecanal is characteristic for H. melpomene, but variation in composition between the individuals was observed. Cluster analysis of compound occurrence in individual bouquets and analyses based on biosynthetic motifs such as functional group, chain length, or basic carbon-backbone modification were used to reveal structural patterns. Mimetic pairs contain different scent bouquets, but also some compounds in common, whereas sympatric species, both mimetic and non-mimetic, have more distinct compound compositions. The compounds identified here may play a role in mate choice thus helping maintain species integrity in a butterfly genus characterized by pervasive interspecific gene flow. 相似文献
908.
Carolina Nachi Rossi Cássia Reika Takabayashi Mario Augusto Ono Jaqueline Gozzi Bordini Osamu Kawamura Edio Vizoni Elisa Yoko Hirooka Elisabete Yurie Sataque Ono 《Food Security》2013,5(4):541-550
The objective of the present study was to assess the degree of exposure of broiler chicken to mycotoxins through naturally contaminated feed and the hygienic quality of feeds. For this purpose the total fungal count and occurrence of fumonisins and aflatoxins were evaluated in four feed types intended for broilers (n?=?158), collected from a poultry breeding farm in northern Paraná State, Brazil. In most feed samples (94 % pre-starter, 91 % starter, 99 % grower and 97 % finisher feeds) the total mould and yeast counts were below 1.0?×?104 CFU/g, the maximum limit established to assure a good hygienic quality of the product. Fumonisins were detected in 94.9 % feed samples at mean levels ranging from 0.52 mg/kg (finisher) to 0.68 mg/kg (pre-starter and grower), while aflatoxins were detected in 72.1 % feed samples at mean levels ranging from 0.0022 mg/kg (pre-starter) to 0.0064 mg/kg (grower). The maximum estimated daily intake of fumonisin B1 for broilers (0.057 mg/kg body weight/day) was below the Lowest Observed Adverse Effect Level (2 mg/kg bw/day). Concerning aflatoxins, most of the positive samples (97 %) showed aflatoxin levels below the maximum limit allowed by the European Commission 0.02 mg aflatoxin B1/kg. Nevertheless, a rigorous monitoring program of the feed producing chain is essential in order to minimize human health hazards. To our knowledge, this is the first report on the degree of exposure of broilers to mycotoxins through naturally contaminated feed in Brazil. 相似文献
909.
María Dolores De’Nobili Carolina Daiana Pérez Diego A. Navarro Carlos A. Stortz Ana M. Rojas 《Food and Bioprocess Technology》2013,6(1):186-197
l-(+)-Ascorbic acid (AA) was compartmentalized into a low methoxyl pectin (LMP) film in view of localized antioxidant activity at food interfaces. The AA hydrolysis was specifically studied in the present work in order to determine the ability of the formulated LMP film to stabilize AA. Hence, films were stored at controlled relative humidity (RH) in the absence of air. A commercial LMP characterized by a 40% degree of methylesterification (DM) was used. Since sucrose is normally added for its standardization, films were also made with the dialyzed LMP in order to determine the sucrose effect. Glycerol was used for plasticization. Kinetics of AA loss and subsequent browning development were determined, which are dependent on the RH. Considerable AA retention (t 1/2?=?744, 727, and 185 days) was achieved at 33.3%, 57.7%, or 75.2% RH, respectively, at 25 °C. Browning rate constants decreased in one order of magnitude with respect to kinetic constants determined from films previously developed with high methoxyl pectin (HMP; DM of 73%). Absence of sucrose in the LMP network only affected the browning kinetics at 75.2% RH. The glass transition temperature (T g) decreased with the increment of moisture content of the films and in a similar degree (T g?≈??90 °C) to that observed for the HMP films, indicating the contribution of water to the network plasticization. However, water was more confined in the LMP network as inferred from the water availability determined by the 1H-NMR and DSC. This was attributed to the water interaction at the Ca2+ junction zones. Sucrose seemed to hinder the retention of water molecules by the polymeric network at 75.2% RH. 相似文献
910.
Dannia Islas-Preciado Gabriela Ugalde-Fuentes Isabel Sollozo-Dupont María Eva Gonzlez Trujano Nancy Cervantes-Anaya Erika Estrada-Camarena Carolina Lpez-Rubalcava 《International journal of molecular sciences》2022,23(13)
Stress susceptibility could play a role in developing premenstrual anxiety due to abnormalities in the hypothalamus–pituitary–adrenal (HPA) axis and impairments in the GABAA receptors’ benzodiazepine (BDZ) site. Hence, we studied the stress-vulnerable Wistar Kyoto rat strain (WKY) to evaluate progesterone withdrawal (PW) effects on anxiety, HPA axis response, and to explore indicators of GABAA functionality in the BDZ site. For five days, ovariectomized WKY rats were administered 2.0 mg/kg of progesterone. Twenty-four hours after the last administration, rats were tested in the anxiety-like burying behavior test (BBT) or elevated plus maze test (EPM), and corticosterone was determined. [3H]Flunitrazepam binding autoradiography served as the BDZ binding site index of the GABAA receptor in amygdala nuclei and hippocampus’s dentate gyrus (DG). Finally, different doses of diazepam in PW-WKY rats were tested in the BBT. PW induced anxiety-like behaviors in both BBT and EPM compared with No-PW rats. PW increased corticosterone, but was blunted when combined with PW and BBT. PW increased [3H]Flunitrazepam binding in the DG and central amygdala compared with No-PW rats. Diazepam at a low dose induced an anxiogenic-like response in PW rats, suggesting a paradoxical response to benzodiazepines. Overall, PW induced anxiety-like behavior, a blunted HPA axis response, and higher GABAAR/BZD binding site sensitivity in a stress-vulnerable rat strain. These findings demonstrate the role of stress-susceptibility in GABAAR functionality in a preclinical approximation of PMDD. 相似文献