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101.
102.
RT-qPCR is the gold standard and the most commonly used method for measuring gene expression. Selection of appropriate reference gene(s) for normalization is a crucial part of RT-qPCR experimental design, which allows accurate quantification and reliability of the results. Because there is no universal reference gene and even commonly used housekeeping genes’ expression can vary under certain conditions, careful selection of an appropriate internal control must be performed for each cell type or tissue and experimental design. The aim of this study was to identify the most stable reference genes during osteogenic differentiation of the human osteosarcoma cell lines MG-63, HOS, and SaOS-2 using the geNorm, NormFinder, and BestKeeper statistical algorithms. Our results show that TBP, PPIA, YWHAZ, and EF1A1 are the most stably expressed genes, while ACTB, and 18S rRNA expressions are most variable. These data provide a basis for future RT-qPCR normalizations when studying gene expression during osteogenic differentiation, for example, in studies of osteoporosis and other bone diseases.  相似文献   
103.
Skin disorders are widespread around the world, affecting people of all ages, and oxidative stress represents one of the main causes of alteration in the normal physiological parameters of skin cells. In this work, we combined a natural protein, fibroin, with antioxidant compounds extracted in water from pomegranate waste. We demonstrate the effective and facile fabrication of bioactive and eco-sustainable films of potential interest for skin repair. The blended films are visually transparent (around 90%); flexible; stable in physiological conditions and in the presence of trypsin for 12 days; able to release the bioactive compounds in a controlled manner; based on Fickian diffusion; and biocompatible towards the main skin cells, keratinocytes and fibroblasts. Furthermore, reactive oxygen species (ROS) production tests demonstrated the high capacity of our films to reduce the oxidative stress induced in cells, which is responsible for various skin diseases.  相似文献   
104.
This paper discusses the feasibility of using neural networks as a tool in the fault detection process. A neural network is integrated with a state language programmable logic controller, an important device in an automatic control system. Time series data related to time spent in a state is gathered and used as input into a neural network, for the purpose of identifying when a fault has occurred. A feedforward neural network is used to identify which (if any) of three types of faults may have occurred. Experimental results related to sensitivity and accuracy measures are presented. A brief review of related applications and research is also presented.  相似文献   
105.
This article presents the findings of an exploratory study of education graduate students’ information-seeking behavior and attitudes. Qualitative data included interviews with education students, focusing on their research habits, and analyzed from phenomenographic approach that focused on variations in individuals’ experiences. The quantitative analysis stemmed from participants’ responses to the survey of their information-seeking behavior. A comparison of interview participants and survey respondents’ search skills, research strategies, and attitudes toward previous library instruction illustrate the wide variation in students’ abilities and experiences between the groups. This suggests the need for further analysis of these students’ information seeking behaviors.  相似文献   
106.
The use of pointers presents serious problems for software productivity tools for software understanding, restructuring, and testing. Pointers enable indirect memory accesses through pointer dereferences, as well as indirect procedure calls (e.g., through function pointers in C). Such indirect accesses and calls can be disambiguated with pointer analysis. In this paper we evaluate the precision of one specific pointer analysis (the FA pointer analysis by Zhang et al.) for the purposes of call graph construction for C programs with function pointers. The analysis is incorporated in a production-strength code-browsing tool from Siemens Corporate Research in which the program call graph is used as a primary tool for code understanding.The FA pointer analysis uses an inexpensive, almost-linear, flow- and context-insensitive algorithm. To measure analysis precision, we compare the call graph constructed by this analysis with the most precise call graph obtainable by a large category of existing pointer analyses. Surprisingly, for all our data programs the FA analysis achieves the best possible precision. This result indicates that for the purposes of call graph construction, inexpensive pointer analyses may provide precision comparable to the precision of expensive pointer analyses.  相似文献   
107.
The primary purpose of this paper is to discuss the role of empathy in the design of advanced systems in manufacturing and service industries in order to ensure suitable working conditions for employees from the social and technological point of view. The origins and components of empathy are briefly reviewed. The neural underpinnings of three components of empathy, including cognitive, emotional, and behavioral aspects, are considered in the context of human–human and human–machine interactions, as well as design of working environments. Finally, the potential advantages of applying empathy‐related knowledge to the design and development of human‐centered technology are discussed.  相似文献   
108.
Feeding agro-industrial by-products and unconventional forages, rich in potentially anti-nutritional factors, may influence the quality of the raw milk and the dairy products prepared therefrom. The aim of the present study was to determine side-effects on physicochemical properties of milk, yoghurt and cheese of feeding diets where one third were feeds either rich in lipids (tomato pomace and olive cake) or phenols (olive leaves and lentil straw) or electrolytes (Atriplex leaves). The diets, including a control diet, were designed to be isoenergetic and isonitrogenous. They were fed in amounts of 25 kg dry matter/day per head during 50 days to 6×10 multiparous fat-tailed Awassi ewes. Milk samples were analysed for various physicochemical traits and fatty acid composition on days 0, 24, 36 and 48. Three times, milk pooled by group was processed to yoghurt and non-aged farmer-type cheese, which were analysed for their gross and fatty acid composition and texture, and were subjected to sensory evaluation. Feeding olive cake and tomato pomace reduced milk casein, but increased proportions of monounsaturated fatty acids. There were some variations in minerals among test diets but, contrary to expectations, Atriplex did not increase milk sodium. The nutritional composition of yoghurt and cheese was not varied much by the test feeds, except for some changes in fatty acid profile similar to the milk. Yoghurt firmness declined with all test diets, but texture score tended to be lower only for olive cake and leaf diets relative to control. Cheese firmness was increased by feeding the Atriplex leaf and olive cake diets which was also reflected in the texture scores. No off-flavours were reported. Possible reasons for effects on the dairy products are discussed. In conclusion, the feeds investigated had certain effects on the physicochemical properties of dairy products, but these were neither very systematic nor large thus not prohibiting their use in Mediterranean sheep milk production systems.  相似文献   
109.
Individual tubers from mature plants of cultivars Pentland Dell and Estima were harvested from experimental plots in two successive years and analysed for α‐solanine, α‐chaconine and total glycoalkaloid concentration (α‐solanine and α‐chaconine combined) using high‐performance liquid chromatography. Mean tuber glycoalkaloid concentration per plant was strongly affected by genotype and was much higher in plants of Pentland Dell (10.0 and 16.3 mg per 100 g fresh weight in 1994 and 1995, respectively) than Estima (4.0 and 4.3 mg per 100 g fresh weight in 1994 and 1995, respectively). The variation between plants in mean tuber glycoalkaloid concentration, expressed as coefficient of variation, was similar for the two cultivars in both years. Variation within plants was higher for cultivar Pentland Dell than Estima for both years but it was statistically significant only in 1995. Tuber position within a plant had no effect on glycoalkaloid concentrations in tubers of similar size. An inverse relationship between total glycoalkaloid concentration and tuber fresh weight of individual tubers was found for both cultivars and small tubers of Pentland Dell (20–40 g fresh weight) exceeded the safety limit of 20 mg per 100 g fresh weight. The pattern of glycoalkaloid accumulation differed between genotypes and appeared related to tuber growth. The implications of these results in terms of food safety are discussed. © 1999 Society of Chemical Industry  相似文献   
110.
The indoor environment is an important venue for exposure to fine particulate matter (PM2.5) of ambient (outdoor) origin. In this work, paired indoor and outdoor PM2.5 species concentrations from three geographically distinct cities (Houston, TX, Los Angeles County, CA, and Elizabeth, NJ) were analyzed using positive matrix factorization (PMF) and demonstrate that the composition and source contributions of ambient PM2.5 are substantially modified by outdoor-to-indoor transport. Our results suggest that predictions of "indoor PM2.5 of ambient origin" are improved when ambient PM2.5 is treated as a combination of four distinct particle types with differing infiltration behavior (primary combustion, secondary sulfate and organics, secondary nitrate, and mechanically generated PM) rather than as a "single internally mixed entity". Study-wide average infiltration factors (i.e., fraction of ambient PM2.5 found indoors) for Relationship of Indoor, Outdoor, and Personal Air (RIOPA) study homes were 0.51, 0.78, and 0.04 (consistent with P = 0.6, 0.9, and 0.09; k = 0.2, 0.1, and 0.6 h(-1)) for PM2.5 associated with primary combustion, secondary formation (excluding nitrate), and mechanical generation, respectively. Modification of the composition, properties, and source contributions of ambient PM2.5 in indoor environments has important implications for exposure mitigation strategies, development of health hypotheses, and evaluation of exposure error in epidemiological studies that use ambient central-site PM2.5 as a surrogate for PM2.5 exposure.  相似文献   
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