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991.
The sensory and physiochemical properties of sausages with varying fat and salt levels were investigated. Twenty eight sausages were produced with varying concentrations of fat (22.5%, 27.5%, 32.5%, 37.5% w/w) and salt (0.8%, 1%, 1.2%, 1.4%, 1.6%, 2%, 2.4% w/w). Sausages were assessed instrumentally for colour, moisture, fat, cooking loss and texture profile analysis. Consumers (n = 25), evaluated each product in duplicate for colour, texture, tenderness, juiciness, salt taste, meat flavour, off-flavour and overall acceptability using a hedonic scale.  相似文献   
992.
This is an exploratory study in order to elucidate the potential of using Raman spectroscopy (785 nm excitation) for quantitative measurements of carotenoid, collagen and fat in fish muscle. Raman spectra were collected from fish fillets of species known to be either high or low in carotenoids, collagen or fat. A pre-treatment routine was used to remove unwanted fluorescence signals from the spectra. Chemical origin of the spectral peaks were identified by literature references as well as reference measurements on pure components. Semi-quantitative analyses were performed by principal component analysis (PCA) of the spectra. The results show that fish muscle exhibits little fluorescence for 785 nm excitation, enabling efficient Raman analysis. The Raman spectra contained detailed spectral information and relative concentration information about all the studied constituents. Raman spectroscopy might be a useful tool for rapid and nondestructive analysis of fish quality.  相似文献   
993.
Very few studies have defined trajectories of smoking. In the present study, we modeled growth in adolescent smoking and empirically identified prototypical trajectories. We conceptualized escalation of smoking as a growth process and modeled rates of change and heterogeneity of these patterns using latent growth mixture modeling. The analysis identified six trajectories with low ambiguity about group membership (early rapid escalators, late rapid escalators, late moderate escalators, late slow escalators-smokers, stable puffers, and late slow escalators-puffers). A trajectory of quitters was not identified. We also examined predictors of the smoking trajectories. The predictors were assessed across the adolescent years and included variables related to smoking and other substance use, as well as a range of variables related to sociodemographic factors and mental health. Observed change in the pattern of predictors across age has implications for the mechanism of effect of these variables in relation to smoking trajectories, including predictors that differentiated among daily smokers, variables that may determine the trajectory (e.g., friends smoking), and variables that may result from the trajectory (e.g., marijuana use, less attachment to friends).  相似文献   
994.
Changes in aqueous- and solid-phase Pu oxidation state were monitored over time in magnetite (Fe3O4) suspensions containing 239Pu(V)-amended 0.01 M NaCl. Oxidation state distribution was determined by leaching of Pu into an aqueous phase followed by an ultrafiltration/solvent extraction technique. The capability of the technique to measure Pu oxidation state distribution was verified using 230Th(IV), 237Np(V), and 233U(VI) as oxidation state analogues. Reduction of Pu(V) was observed at all pH values (pH 3 to 8) and magnetite concentrations (10 to 100 m2 L(-1)). In the pH range 5 to 8, adsorption was a rate-limiting step, and reduction was mediated by the solid phase; at pH 3 reduction occurred in the aqueous phase. The overall reaction (describing both adsorption and reduction of Pu(V)) was found to be approximately first order with respect to the magnetite concentration and of order -0.34+/-0.02 with respect to the hydrogen ion concentration. Assuming first order dependence with respect to Pu, the overall reaction rate constant was calculated as k(rxn) = 4.79+/-0.62 x 10(-8) (m(-2) L)0.99(mol(-1) L)-0.34(s(-1)). The Pu(IV) solid-phase species became more stable over time.  相似文献   
995.
996.
997.
This study accumulated European consumer attitudes towards processed meats and their use as a functional food. A survey was set up using an online web-application to gather information on consumer perception of processed meats as well as neutraceutical-containing processed meats. 548 responses were obtained and statistical analysis was carried out using a statistical software package. Data was summarized as frequencies for each question and statistical differences analyzed using the Chi-Square statistical test with a significance level of 5% (P < 0.05). The majority of consumer attitudes towards processed meat indicate that they are unhealthy products. Most believe that processed meats contain large quantities of harmful chemicals, fat and salt. Consumers were found to be very pro-bioactive compounds in yogurt style products but unsure of their feelings in meat based products, which is likely due to the lack of familiarity to these products. Many of the respondents were willing to consume meat based functional foods but were not willing to pay more for them.  相似文献   
998.
Abstract

This article focuses on monitor plans aimed at the early detection of the increase in the frequency of events. The literature recommends either monitoring the time between events (TBE) if events are rare or counting the number of events per unit non-overlapping time intervals otherwise. Some authors advocate using the Bernoulli model for rare events, applying presence or absence of events within non-overlapping and exhaustive time intervals. This Bernoulli model does improve the real-time monitoring assessment of these events compared to counting events over a larger interval, making them less rare. However this approach became inefficient if more than one event starts occurring within the intervals. Monitoring TBE is the real-time option for outbreak detection, because outbreak information is accumulated when an event occurs. This is preferred to waiting for the end of a period to count events. If the TBE reduces significantly, then the incidence of these events increases significantly. This article explores this TBE option relative to using the monitoring of counts when the TBEs are either Exponentially, Gamma or Weibull distributed for moderately low count scenarios. The article will discuss and compare the approaches of using an Exponentially Weighted Moving Average (EWMA) statistic for the TBEs to the EWMA of counts. Several robust options will be considered when the future change in event frequency is unknown. Our goal is to have a robust monitoring plan which is able to efficiently detect many different levels of shifts. These robust plans are compared to the more traditional event monitoring plans for both small and large changes in the event frequency.  相似文献   
999.
Li  Yong  Liu  Xifeng  Gaihre  Bipin  Li  Linli  Rezaei  Asghar  Miller  A. Lee  Waletzki  Brian  Park  Sungjo  Terzic  Andre  Lu  Lichun 《Journal of Materials Science》2022,57(10):5998-6012

Hydroxyapatite (HA) is a bioceramic material that shares similar crystal and chemical structures with inorganic components of the bone. However, HA lacks osteoinductive activity and has a brittle nature, making it challenging to apply for direct load-bearing bone applications. In this study, we used a wet chemical method to synthesize zinc-doped hydroxyapatite powders with different Zn/(Zn+Ca) molar ratios of 0, 0.025, 0.05, and 0.1. The corresponding Zn-HA was designated as HA, Zn2.5-HA, Zn5-HA, and Zn10-HA. The Zn-HA powders at 30 wt% were used to fabricate poly(propylene fumarate) (PPF)-based nanocomposite scaffolds (HA/PPF, Zn2.5-HA/PPF, Zn5-HA/PPF, and Zn10-HA/PPF). The physical properties of obtained scaffolds were examined by scanning electron microscopy, energy-dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), and atomic force microscopy (AFM). Live/dead cell viability assay showed that these scaffolds were biocompatible and supported excellent adhesion of MC3T3-E1 preosteoblast cells. Additionally, the proliferation of cells was detected at 1, 4, and 7 days on these scaffolds. Alkaline phosphatase (ALP) activity measurement and alizarin red staining showed good osteogenic differentiation and matrix mineralization for MC3T3-E1 cells growing on these scaffolds. Taken together, the results here indicate that Zn5-HA/PPF nanocomposite scaffolds are promising scaffold material for bone tissue engineering.

Graphical abstract
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1000.
Lattice parameter changes can be detected by the use of a previously established technique which is based upon computer simulation of HOLZ patterns. This simulation technique is then applied to two precipitation phenomena in Nimonic PE16. Firstly, the growth of gamma prime, γ, precipitates from a solid solution is monitored via the decrease in lattice parameter of the parent phase, and secondly the lattice parameter of coarsened, overaged γ is measured for precipitates sited both at grain boundaries and within grains. The variations thus detected between intergranular and intragranular precipitates are attributed to changes in the Ti/Al ratio due to preferential γ coarsening at the grain boundary. The very subtle compositional changes inferred (~1 at. % Ti) would have been very difficult to establish by chemical analysis, but can be easily measured by convergent beam electron diffraction.  相似文献   
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