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61.
Phytic acid (PA) is a strong anti-nutritional factor with a key antioxidant role in countering reactive oxygen species. Despite the potential benefits of low phytic acid (lpa) mutants, the reduction of PA causes pleiotropic effects, e.g., reduced seed germination and viability loss related to seed ageing. The current study evaluated a historical series of naturally aged seeds and showed that lpa1-1 seeds aged faster as compared to wildtype. To mimic natural ageing, the present study set up accelerated ageing treatments at different temperatures. It was found that incubating the seeds at 57 °C for 24 h, the wildtype germinated at 82.4% and lpa1-1 at 40%. The current study also hypothesized two possible solutions to overcome these problems: (1) Classical breeding was used to constitute synthetic populations carrying the lpa1-1 mutation, with genes pushing anthocyanin accumulation in the embryo (R-navajo allele). The outcome showed that the presence of R-navajo in the lpa1-1 genotype was not able to improve the germinability (−20%), but this approach could be useful to improve the germinability in non-mutant genotypes (+17%). (2) In addition, hydropriming was tested on lpa1-1 and wildtype seeds, and germination was improved by 20% in lpa1-1, suggesting a positive role of seed priming in restoring germination. Moreover, the data highlighted metabolic differences in the metabolome before and after hydropriming treatment, suggesting that the differences in germination could also be mediated by differences in the metabolic composition induced by the mutation.  相似文献   
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Ammonium removal from the wastewater treatment effluents is mandatory considering the imposed discharge limits and the recycling/reuse requirements. Ion exchange represents a viable alternative for the biological processes of ammonium removal, although concurrent processes make modeling complex. This study reports on the performance of a commercial cation exchange resin, PUROLITE C150H, for ammonium removal from synthetic aqueous solutions. Thermodynamic and kinetic process parameters are calculated using the Langmuir model (thermodynamic study) and the shrinking core model (kinetic study); the data are correlated with the surface properties of the substrate, outlining the adsorption mechanism. For initial ammonium concentrations of 25–150 mg NH4 +/L, removal efficiencies of 80–90 % were obtained.  相似文献   
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Gaussian beam launching is proposed as an alternative to ray-based techniques for propagation channel modeling, and it is implemented and validated in the context of indoor propagation. A rigorous Gabor frame decomposition of source fields is used to represent a radiated field as a superposition of shifted and rotated Gaussian beams, conveniently expressed as complex rays. Beam tracking through multiple reflections and transmissions is straightforward, and fields can then be evaluated by summation of closed form expressions. The parameters of a given transformed Gaussian beam have to be calculated only once for all observation points, leading to easy implementation, and computationally efficient algorithms. Simulations of amplitude–delay profiles, mean excess delay, and RMS delay spread are performed in an indoor environment at 60 GHz and compared to measured and published results.  相似文献   
65.
Chicken meat is well known for its high nutritional value. Its shelf life is short, due to the pronounced perishability, even under refrigeration. Paper bags are usually used as packaging materials, due to their biodegradability. The main negative aspect concerning paper is its high porosity and low moisture barrier. In this regard, it has to be coated/modified with efficient moisture barrier materials. The storage of chicken breast meat wrapped in four types of paper-based materials currently in use in Romania (RO), Italy (IT), Spain (SP) and Slovenia (SLO) is reported. RO and IT are paper coated with polyethylene (PE) film, SP is waxed paper, and SLO is paper modified with hydrophobized starch. The influence of the coating film on the organoleptical, biochemical and microbiological characteristics of the chicken breast meat stored at 4°C was the aim of the study. The mathematical modelling revealed two aspects: (1) the stability period in which the meat safe for consumption is in the range 1.92–2.18 days in the case of all paper types, and (2) cadaverine, the amine generated by protein degradation, is a less sensitive indicator of the meat alteration than microbial growth. The papers coated with PE (RO and IT samples) and with hydrophobized starch (SLO paper) were packaging materials more efficient that the waxed paper (SP sample). The polyethylene film reduced the conversion of putrescine into spermidine in a higher extent than wax.  相似文献   
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Water Resources Management - Floods are among the most severe natural hazard phenomena that affect people around the world. Due to this fact, the identification of zones highly susceptible to...  相似文献   
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Background: The interleukin-1-receptor antagonist IL1RA (encoded by the IL1RN gene) is a potent competitive antagonist to interleukin-1 (IL1) and thereby is mainly involved in the regulation of inflammation. Previous data indicated a role of IL1RA in muscle-invasive urothelial carcinoma of the bladder (UCB) as well as an IL1-dependent decrease in tissue barrier function, potentially contributing to cancer cell invasion. Objective: Based on these observations, here we investigated the potential roles of IL1RA, IL1A, and IL1B in bladder cancer cell invasion in vitro. Methods: Cell culture, real-time impedance sensing, invasion assays (Boyden chamber, pig bladder model), qPCR, Western blot, ELISA, gene overexpression. Results: We observed a loss of IL1RA expression in invasive, high-grade bladder cancer cell lines T24, UMUC-3, and HT1197 while IL1RA expression was readily detectable in the immortalized UROtsa cells, the non-invasive bladder cancer cell line RT4, and in benign patient urothelium. Thus, we modified the invasive human bladder cancer cell line T24 to ectopically express IL1RA, and measured changes in cell migration/invasion using the xCELLigence Real-Time-Cell-Analysis (RTCA) system and the Boyden chamber assay. The real-time observation data showed a significant decrease of cell migration and invasion in T24 cells overexpressing IL1RA (T24-IL1RA), compared to cells harboring an empty vector (T24-EV). Concurrently, tumor cytokines, e.g., IL1B, attenuated the vascular endothelial barrier, which resulted in a reduction of the Cell Index (CI), an impedance-based dimensionless unit. This reduction could be reverted by the simultaneous incubation with IL1RA. Moreover, we used an ex vivo porcine organ culture system to evaluate cell invasion capacity and showed that T24-IL1RA cells showed significantly less invasive capacity compared to parental T24 cells or T24-EV. Conclusions: Taken together, our results indicate an inverse correlation between IL1RA expression and tumor cell invasive capacity and migration, suggesting that IL1RA plays a role in bladder carcinogenesis, while the exact mechanisms by which IL1RA influences tumor cells migration/invasion remain to be clarified in future studies. Furthermore, we confirmed that real-time impedance sensing and the porcine ex vivo organ culture methods are powerful tools to discover differences in cancer cell migration and invasion.  相似文献   
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(1) Background: Biomarkers might play a significant role in predicting the clinical outcomes of patients with ovarian cancer. By analyzing lipid metabolism genes, future perspectives may be uncovered; (2) Methods: RNA-seq data for serous ovarian cancer were downloaded from The Cancer Genome Atlas and Gene Expression Omnibus databases. The non-negative matrix factorization package in programming language R was used to classify molecular subtypes of lipid metabolism genes and the limma package in R was performed for functional enrichment analysis. Through lasso regression, we constructed a multi-gene prognosis model; (3) Results: Two molecular subtypes were obtained and an 11-gene signature was constructed (PI3, RGS, ADORA3, CH25H, CCDC80, PTGER3, MATK, KLRB1, CCL19, CXCL9 and CXCL10). Our prognostic model shows a good independent prognostic ability in ovarian cancer. In a nomogram, the predictive efficiency was notably superior to that of traditional clinical features. Related to known models in ovarian cancer with a comparable amount of genes, ours has the highest concordance index; (4) Conclusions: We propose an 11-gene signature prognosis prediction model based on lipid metabolism genes in serous ovarian cancer.  相似文献   
70.
Ricotta is a highly perishable cheese of which shelf-life is strongly influenced by the properties of packages in which it is stored. Four plastic packages currently in use in Italy (IT), Romania (RO), Slovenia (SLO), and Spain (SP) are characterized in term of structure, barrier, and antimicrobial properties, and their efficiency in the ricotta storage at 4°C is assessed. Differential scanning calorimetry and Fourier-transform infrared spectroscopy analysis indicate that the IT and SP packages are made of low-density polyethylene and the RO and SLO packages consist of polyethylene and polyamide 6. Permeability to the water vapour and oxygen transmission rate vary as follows: IT>SLO > RO > SP and SP > IT>RO > SLO, respectively. The SP package expressed the highest antimicrobial inhibition whilst the IT package the lowest. The maximum amounts of volatile compounds in cheese were reached after 3 days in the IT and SP packages and after 6 days in the SLO and RO packages. The score 2.8 for cheese overall acceptability was exceeded after 7 days in the IT, RO, and SP packages and 6 days in the SLO package. Barrier properties of packages significantly influence the shelf-life of ricotta. Low barrier properties resulted in high level of oxygen and water vapours inside the headspace of packages ultimately favour the microbial development. The simultaneous compliance of microbiological safety level and overall acceptability score gives ricotta a shelf-life of 3 days in the IT, RO, and SP packages and 1 day in the SLO package.  相似文献   
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