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1.
Talita Moreira de Oliveira Nilda de Fátima Ferreira Soares Rodrigo Magela Pereira Kátia de Freitas Fraga 《Packaging Technology and Science》2007,20(2):147-153
Conservation of food products depends on product quality and packaging suitability. The objective of this work was to develop and evaluate the antimicrobial efficiency of natamycin‐incorporated film in the production process of Gorgonzola cheese. It aims to optimize the production process and increase shelf‐life and food safety for the consumer. Films with different concentrations of natamycin were produced and tested in Gorgonzola cheeses to evaluate its efficiency against Penicillium roqueforti on the cheese surface. Films with 2 and 4% natamycin presented satisfactory results for fungus inhibition and the amount of natamycin released to the cheese was below that allowed by the legislation. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
2.
F Zindy H Soares KH Herzog J Morgan CJ Sherr MF Roussel 《Canadian Metallurgical Quarterly》1997,8(11):1139-1150
In situ hybridization of mouse embryo sections demonstrated expression of mRNAs encoding two polypeptide inhibitors (p18INK4c and p19INK4d) of cyclin D-dependent kinase (CDK) 4 and CDK6 in the central nervous system. No expression of two other INK4 members, p16INK4a and p15INK4b, was observed. The p19INK4d and p18INK4c proteins formed complexes with either CDK4 or CDK6 in a temporal pattern consistent with the results of in situ hybridization. Expression of INK4c was observed at embryonic day 13.5 in neuroepithelial zones of the developing brain, being restricted to dividing neuroblasts but absent from differentiating postmitotic neurons. In the neocortex, p18INK4c was expressed precisely at those developmental stages when neuroblasts switch from a symmetric to an asymmetric pattern of cell division with concomitant increases in their G1 interval. INK4d RNA was detected from embryonic day 11.5 onward, at higher levels than INK4c and with a distinctly different spatial and temporal pattern. Marked INK4d expression was seen in dorsal root ganglia, spinal cord, and focally throughout the brain, but primarily in postmitotic neurons. Neural expression of INK4d continued postnatally into adulthood in postmitotic cells of the dentate gyrus, the pyramidal layer of the hippocampus, and in discrete regions of the cerebral cortex, cerebellum, thalamus, and brainstem. Downregulation of p19INK4d in the dentate gyrus after kainic acid-induced seizures indicated that its expression could also be modified in nondividing cells by excitotoxic stress. Therefore, p19INK4d may contribute to maintaining the quiescent state, acting as a buffer to prevent reactivation of cyclin D-dependent kinases in terminally differentiated cells. 相似文献
3.
Cohen S.S. Soares A.M. Gleason E.F. Wyatt P.W. Raffel J.I. 《Electron Devices, IEEE Transactions on》1993,40(7):1277-1283
A metal-insulator-metal (MIM) capacitor structure has been developed for use in field-programmable gate arrays (FPGAs) as a voltage-programmable link (VPL). The structure relies on a combination of a refractory metal and aluminum as the lower electrode, and either a similar combination or aluminum alone as the top electrode. The insulator is prepared by means of plasma-enhanced chemical vapor deposition (PECVD). It comprises a sandwich of nearly stoichiometric silicon dioxide interposed between two like layers of silicon-rich silicon nitride. The structure has displayed characteristics desirable for use in emerging FPGA technology, including high density, low on-resistance, reduced capacitance, and low programming voltage 相似文献
4.
B. Herreros G. Lifante A. Kling J.C. Soares M.F. da Silva P.D. Townsend P.J. Chandler J. Olivares J.M. Cabrera 《Optical Materials》1996,6(4):281-286
We present a structural study of two Nd3+/MgO codoped LiNbO3 waveguides fabricated by two different methods: ion-implantation and proton-exchange. Rutherford backscattering spectrometry in combination with channelling was used to study the influence of the waveguide fabrication method on the possible modification of the LiNbO3 crystal structure within the waveguiding layer. The results show that the ion-implanted waveguide mainly maintains the same properties as the virgin crystal, apart from a deterioration of a thin surface layer, whilst the proton-exchanged waveguide exhibits a quite different behaviour, although its surface is less damaged. 相似文献
5.
The effect of aluminium on the equilibrium phases of the Cu-Zn alloys has been studied within the range of chemical compositions
of interest to brass producers. Ternary alloys were cast by melting two Cu-Zn base alloys (with ∼59.5% and ∼61.2 wt.% Cu)
followed by the addition of aluminium up to 3.68 wt.%. Isothermal homogenization, followed by rapid cooling, has been used
to determine the equilibrium phases at different temperatures. The alloys have been observed by scanning electron microscopy
(SEM) and the respective chemical analysis determined by electron probe microanalysis (EPMA). Statistical analysis of the
results enables a correlation of the chemical compositions of the equilibrium phases with temperature within composition range
of the study. 相似文献
6.
In this paper, an original spatial shape error-concealment technique, to be used in the context of object-based image and video coding schemes, is proposed. In this technique, it is assumed that the shape of the corrupted object at hand is in the form of a binary alpha plane, in which some of the shape data is missing due to channel errors. From this alpha plane, a contour corresponding to the border of the object can be extracted. However, due to errors, some parts of the contour will be missing and, therefore, the contour will be broken. The proposed technique relies on the interpolation of the missing contours with Bézier curves, which is done based on the available surrounding contours. After all the missing parts of the contour have been interpolated, the concealed alpha plane can be easily reconstructed from the fully recovered contour and used instead of the erroneous one improving the final subjective impact. 相似文献
7.
8.
Two-phase partitioning bioreactors offer many advantages for the removal of toxic pollutants. In particular, such systems can be loaded with very large quantities of pollutants without risks of microbial inhibition, they are self-regulated and they prevent the risks of hazardous pollutant volatilisation during aerobic treatment. However, their potential has never been tested at low temperatures. Phenol biodegradation by a cold adapted Pseudomonas strain was therefore tested at 14 or 4 degrees C using 2-undecanone, diethyl sebacate or 2-decanone as organic phases in a two-phase partitioning bioreactor. The three solvents were biocompatible at 14 degrees C but evidence was found that diethyl sebacate was biodegraded by the bacteria and this solvent was not tested further. Although only 2-decanone was suitable at 4 degrees C, phenol biodegradation was more efficient in 2-undecanone at 14 degrees C, reaching a maximum volumetric rate (based on the volume of aqueous phase) of approximately 1.94 g/L.day after 47 h of cultivation. In 2-decanone at 14 degrees C, evidence was found that phenol degradation was limited by the release of biosurfactants, which increased the solubility and toxicity of the solvent in the aqueous phase inhibiting microbial activity. This study therefore shows that pollutant removal at low temperature is feasible but that the production of biosurfactants can have a negative impact on the process and must be taken into consideration when selecting the organic solvent. Future work should therefore focus on the selection of solvents suitable for use at temperatures below 14 degrees C. 相似文献
9.
Luciana Juncioni de Arauz Angela Faustino Jozala Gabriel Soares Pinheiro Priscila Gava Mazzola Adalberto Pessoa Júnior Thereza Christina Vessoni Penna 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2008,83(3):325-328
BACKGROUND: Nisin is a commercially available bacteriocin produced by Lactococcus lactis ATCC 11454 and used as a natural agent in the biopreservation of food. In the current investigation, milk whey, a byproduct from dairy industries was used as a fermentation substrate for the production of nisin. Lactococcus lactis ATCC 11454 was developed in a rotary shaker (30 °C/36 h/100 rpm) using two different media with milk whey (i) without filtration, pH 6.8, adjusted with NaOH 2 mol L?1 and without pH adjustment, both autoclaved at 121 °C for 30 min, and (ii) filtrated (1.20 µm and 0.22 µm membrane filter). These cultures were transferred five times using 5 mL aliquots of broth culture for every new volume of the respective media. RESULTS: The results showed that culture media composed of milk whey without filtration supplied L. lactis its adaptation needs better than filtrated milk whey. Nisin titers, in milk whey without filtration (pH adjusted), was 11120.13 mg L?1 in the second transfer, and up to 1628‐fold higher than the filtrated milk whey, 6.83 mg.L?1 obtained in the firstt transfer. CONCLUSIONS: Biological processing of milk byproducts (milk whey) can be considered a profitable alternative, generating high‐value bioproducts and contributing to decreasing river disposals by dairy industries. Copyright © 2008 Society of Chemical Industry 相似文献
10.
Sofia Cotton Dylan Ferreira Janine Soares Andreia Peixoto Marta Relvas-Santos Rita Azevedo Paulina Piairo Lorena Diguez Carlos Palmeira Luís Lima Andr M. N. Silva Lúcio Lara Santos Jos Alexandre Ferreira 《International journal of molecular sciences》2021,22(4)
Esophageal cancer (EC) is a life-threatening disease, demanding the discovery of new biomarkers and molecular targets for precision oncology. Aberrantly glycosylated proteins hold tremendous potential towards this objective. In the current study, a series of esophageal squamous cell carcinomas (ESCC) and EC-derived circulating tumor cells (CTCs) were screened by immunoassays for the sialyl-Tn (STn) antigen, a glycan rarely expressed in healthy tissues and widely observed in aggressive gastrointestinal cancers. An ESCC cell model was glycoengineered to express STn and characterized in relation to cell proliferation and invasion in vitro. STn was found to be widely present in ESCC (70% of tumors) and in CTCs in 20% of patients, being associated with general recurrence and reduced survival. Furthermore, STn expression in ESCC cells increased invasion in vitro, while reducing cancer cells proliferation. In parallel, an ESCC mass spectrometry-based proteomics dataset, obtained from the PRIDE database, was comprehensively interrogated for abnormally glycosylated proteins. Data integration with the Target Score, an algorithm developed in-house, pinpointed the glucose transporter type 1 (GLUT1) as a biomarker of poor prognosis. GLUT1-STn glycoproteoforms were latter identified in tumor tissues in patients facing worst prognosis. Furthermore, healthy human tissues analysis suggested that STn glycosylation provided cancer specificity to GLUT1. In conclusion, STn is a biomarker of worst prognosis in EC and GLUT1-STn glycoforms may be used to increase its specificity on the stratification and targeting of aggressive ESCC forms. 相似文献