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791.
Birgitta Strandvik Susanne Eriksson Malin Garemo Vilborg Palsdottir Sabine Sampels Jana Pickova 《Lipid Technology》2008,20(3):57-59
Alongside the increase of overweight and obesity in the world there is the avoidance of saturated fat and an increased dietary use of vegetable oils rich in omega‐6 fatty acids. These changes result in a marked increase of the omega‐6/omega‐3 ratio and there is increasing evidence that this changed balance is related to lifestyle diseases. There are also indications that this balance between fatty acids may be involved in epigenetics, i. e. that it influences metabolic pathways during intra‐uterine or early life which cause diseases later in life. Such processes would be a possible explanation for the epidemic outburst of obesity during the latest decades. 相似文献
792.
Oscar?JalnefjordEmail authorView authors OrcID profile Mats?Andersson Mikael?Montelius G?ran?Starck Anna-Karin?Elf Viktor?Johanson Johanna?Svensson Maria?Ljungberg 《Magma (New York, N.Y.)》2018,31(6):715-723
Objective
Intravoxel incoherent motion (IVIM) shows great potential in many applications, e.g., tumor tissue characterization. To reduce image-quality demands, various IVIM analysis approaches restricted to the diffusion coefficient (D) and the perfusion fraction (f) are increasingly being employed. In this work, the impact of estimation approach for D and f is studied.Materials and methods
Four approaches for estimating D and f were studied: segmented IVIM fitting, least-squares fitting of a simplified IVIM model (sIVIM), and Bayesian fitting of the sIVIM model using marginal posterior modes or posterior means. The estimation approaches were evaluated in terms of bias and variability as well as ability for differentiation between tumor and healthy liver tissue using simulated and in vivo data.Results
All estimation approaches had similar variability and ability for differentiation and negligible bias, except for the Bayesian posterior mean of f, which was substantially biased. Combined use of D and f improved tumor-to-liver tissue differentiation compared with using D or f separately.Discussion
The similar performance between estimation approaches renders the segmented one preferable due to lower numerical complexity and shorter computational time. Superior tissue differentiation when combining D and f suggests complementary biologically relevant information.793.
Narusyte Jurgita; Neiderhiser Jenae M.; Andershed Anna-Karin; D'Onofrio Brian M.; Reiss David; Spotts Erica; Ganiban Jody; Lichtenstein Paul 《Canadian Metallurgical Quarterly》2011,120(2):365
Genetic factors are important for the association between parental negativity and child problem behavior, but it is not clear whether this is due to passive or evocative genotype–environment correlation (rGE). In this study, we applied the extended children-of-twins model to directly examine the presence of passive and evocative rGE as well as direct environmental effects in the association between parental criticism and adolescent externalizing problem behavior. The cross-sectional data come from the Twin and Offspring Study in Sweden (N = 909 pairs of adult twins) and from the Twin Study of Child and Adolescent Development (N = 915 pairs of twin children). The results revealed that maternal criticism was primarily due to evocative rGE emanating from their adolescent's externalizing behavior. On the other hand, fathers' critical remarks tended to affect adolescent problem behavior in a direct environmental way. This suggests that previously reported differences in caretaking between mothers and fathers also are reflected in differences in why parenting is associated with externalizing behavior in offspring. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
794.
All available thermodynamic and phase diagram data have been critically assessed for all phases in the MnO-TiO2, MgO-TiO2, FeO-TiO2, Ti2O3-TiO2, Na2O-TiO2, and K2O-TiO2 systems at 1 bar pressure from 298 K to above the liquidus temperatures. All reliable thermodynamic and phase diagram data
have been simultaneously optimized to obtain, for each system, one set of model equations for the Gibbs energy of the liquid
slag as a function of composition and temperature and equations for the Gibbs energies of all compounds as functions of temperature.
The modified quasichemical model was used for the molten slag phases. 相似文献
795.
A software-based measurement system using both analogue data acquisition and digital communication via a general-purpose interface bus (GPIB) board has been developed for analysis and evaluation of disc brake squeal. The system is built around a computer and based on commercial software. Brake pressure and torque, rotational speed, five different temperatures, and sound emission are logged once a second. If the sound is characterised as a squeal it is saved to file together with the other parameters. The measurement system is very flexible, allowing for different types of instruments and sensors to be used by adapting the software. Furthermore, the same software is used for evaluation of the collected data. Mechanically, the equipment consists of a complete front wheel suspension where the original brake disc and caliper are mounted in a steel tube chassis. The brake disc is driven by a DC electric motor, while a hydraulic system provides the brake pressure. Brake pressure and rotational speed can be controlled independently. 相似文献
796.
Camilla Eriksson Prof. Sunithi Gunasekera Dr. Taj Muhammad Mingshu Zhang Ida Laurén Prof. Sara M Mangsbo Dr. Martin Lord Prof. Ulf Göransson 《Chembiochem : a European journal of chemical biology》2023,24(15):e202300103
The SARS-CoV-2 virus that causes COVID-19 is a global health issue. The spread of the virus has resulted in seven million deaths to date. The emergence of new viral strains highlights the importance of continuous surveillance of the SARS-CoV-2 virus by using timely and accurate diagnostic tools. Here, we used a stable cyclic peptide scaffolds to present antigenic sequences derived from the spike protein that are reactive to SARS-CoV-2 antibodies. Using peptide sequences from different domains of SARS-CoV-2 spike proteins, we grafted epitopes on the peptide scaffold sunflower trypsin inhibitor 1 (SFTI-1). These scaffold peptides were then used to develop an ELISA to detect SARS-CoV-2 antibodies in serum. We show that displaying epitopes on the scaffold improves reactivity overall. One of the scaffold peptides (S2_1146-1161_c) has reactivity equal to that of commercial assays, and shows diagnostic potential. 相似文献