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971.
Soumya Banerjee Hameed Al-Qaheri Monica Chiş M. B. Ali Hassan 《Telecommunication Systems》2011,46(3):273-284
A central problem in marketing is the clear understanding of consumer’s choice or preferences. Designing questionnaires and
then analyzing the answers of probable customers can achieve this. The traditional approach in the marketing analysis has
been the designing of non-adaptive questionnaires, questionnaires that are predetermined and not at all influenced by respondent’s
answers. The aim of this paper is to design a questionnaire that is influenced by respondent’s answer through implementation
of soft computing and approximate reasoning methodologies. The learning of particular pattern on respondent’s fuzzy responses
has also been envisaged in the post-survey (Post-conjoint) and further better clustering of choices and segregation is accomplished.
The module of learning and finer clustering from respondent’s choice pattern could be a major pre-requisite for construction
of adaptive questionnaires. Further extensions of the soft computing methods for product recommender system have also been
mentioned for the design of adaptive questionnaire. 相似文献
972.
Merli D Ugonino M Profumo A Fagnoni M Quartarone E Mustarelli P Visai L Grandi MS Galinetto P Canton P 《Journal of nanoscience and nanotechnology》2011,11(4):3100-3106
We report a facile strategy to obtain multiwalled carbon nanotubes (MWCNTs) functionalized with covalently bonded lysozyme. The functionalization procedure has been investigated by means of several techniques, including thermogravimetry, Raman spectroscopy, transmission electron microscopy, and cyclic voltammetry. A functionalization of about 1 lysozyme molecule every 4000 carbon atoms is obtained. The modified lysozyme-CNTs nanocomposite shows a significant increase of the antibacterial activity towards the Gram-positive S. aureus if compared with lysozyme in solution. 相似文献
973.
974.
Cotar AI Badescu D Oprea M Dinu S Banu O Dobreanu D Dobreanu M Ionac A Flonta M Straut M 《International journal of molecular sciences》2011,12(12):9504-9513
Infective endocarditis (IE) is a serious, life-threatening disease with highly variable clinical signs, making its diagnostic a real challenge. A diagnosis is readily made if blood cultures are positive, but in 2.5 to 31% of all infective endocarditis cases, routine blood cultures are negative. In such situations, alternative diagnostic approaches are necessary. Coxiella burnetii and Bartonella spp. are the etiological agents of blood culture-negative endocarditis (BCNE) most frequently identified by serology. The purpose of this study is to investigate the usefulness of molecular assays, as complementary methods to the conventional serologic methods for the rapid confirmatory diagnostic of Q fever endocarditis in patients with BCNE. Currently, detection of C. burnetii by culture or an antiphase I IgG antibody titers >800 represents a major Duke criterion for defining IE, while a titers of >800 for IgG antibodies to either B. henselae or B. quintana is used for the diagnosis of endocarditis due to Bartonella spp. We used indirect immunofluorescence assays for the detection of IgG titers for C. burnetii, B. henselae and B. quintana in 57 serum samples from patients with clinical suspicion of IE. Thirty three samples originated from BCNE patients, whereas 24 were tested before obtaining the blood cultures results, which finally were positive. The results of serologic testing showed that nine out of 33 BCNE cases exhibited antiphase I C. burnetii IgG antibody titer >800, whereas none has IgG for B. henselae or B. quintana. Subsequently, we used nested-PCR assay for the amplification of C. burnetii DNA in the nine positive serum samples, and we obtained positive PCR results for all analyzed cases. Afterwards we used the DNA sequencing of amplicons for the repetitive element associated to htpAB gene to confirm the results of nested-PCR. The results of sequencing allowed us to confirm that C. burnetii is the causative microorganism responsible for BCNE. In conclusion, the nested PCR amplification followed by direct sequencing is a reliable and accurate method when applied to serum samples, and it may be used as an additional test to the serological methods for the confirmatory diagnosis of BCNE cases determined by C. burnetii. 相似文献
975.
Optimisation of microwave-assisted acid digestion for the purification of supported carbon nanotubes
Experimental optimisation of microwave-assisted acid digestion for supported carbon nanotube (CNT) purification is reported. Process variables including ramp rate, temperature, duration, scalability, acid type, volume and concentration were investigated using thermogravimetric, Fourier transform infra-red and Raman spectroscopy performance metrics. Key factors in purification were temperature, duration and acid. HNO3 damaged CNTs and introduced carboxyl and C–O functional groups. HCl and H2SO4 achieved similar impurity removal but, despite the incorporation of sulphur-based functional groups, H2SO4 was preferred due to a more homogeneous product. Concentration and volume variables could be condensed into a single factor – the stoichiometric excess of acid to impurities – for process simplification and to permit direct literature comparison. The scalable optimised process increased CNT purity from ∼22 wt% to > 95 wt% with negligible damage in a single 15 min isothermal treatment at 230 °C with a H2SO4 excess of 4.5 times the required stoichiometry (1 M). 相似文献
976.
Real Time PCR for the detection and discrimination of cereal contamination in gluten free foods 总被引:3,自引:0,他引:3
Martin?SandbergEmail author Lisa?Lundberg Monica?Ferm Ingrid?Malmheden Yman 《European Food Research and Technology》2003,217(4):344-349
Real-time PCR methods, using melting curve analysis for product identification, were established for the specific discrimination of wheat, rye, barley and oats in food samples. Specific primers targeting cereal prolamin genes were chosen for the amplification. The lengths of the amplicons varied between 104 and 181 base pairs and the melting point between 81.2 and 85.0 °C. The specificity of the wheat PCR was shown for spring and autumn wheat but also for durum wheat, spelt wheat and kamut. The methods were applied for final food products and for detection of toxic cereal contamination in oat samples. The results of the analysis were compared with those obtained with an established enzyme immuno assay for gluten analysis. The PCR methods give a good correlation with the protein assay and are rapid and sensitive. The PCR methods can thus be used as confirmatory methods in food analysis of gluten-free and naturally gluten-free foods. 相似文献
977.
Characterization and effect of year of harvest on the nutritional properties of three varieties of white lupine (Lupinus albus L.) 下载免费PDF全文
978.
Mammary apoptosis and lactation persistency in dairy animals 总被引:10,自引:0,他引:10
The decline in milk yield after peak lactation in dairy animals has long been a biological conundrum for the mammary biologist, as well as a cause of considerable lost income for the dairy farmer. Recent advances in understanding the control of the mammary cell population now offer new insights on the former, and a potential means of alleviating the latter. The weight of evidence now indicates that a change in mammary cell number, the result of an imbalance between cell proliferation and cell removal, is a principal cause of declining production. Further, it suggests that the persistency of lactation, the rate of decline in milk yield with stage of lactation, is strongly influenced by the rate of cell death by apoptosis in the lactating gland. Mammary apoptosis was first demonstrated during tissue involution after lactation, but has now been detected during lactation, in mammary tissue of lactating mice, goats and cattle. Those factors that determine the rate of cell death by apoptosis are as yet poorly characterized, but include the frequency of milking in lactating goats. Initial evidence suggests that nutrition also is likely to influence cell survival after peak lactation, an important factor being the degree of oxidative stress imposed by feed and the tissue's ability to deal with, and prevent damage by, reactive oxygen species. Comparison of cows in calf or not pregnant during declining lactation also indicates a likely influence of reproductive hormones, with oestradiol and progesterone acting to preserve mammary ductal and alveolar integrity during the dry period, while allowing a degree of apoptosis and cell replacement. In each case, the molecular mechanisms controlling mammary cell survival (or otherwise) are as yet poorly defined. On the other hand, more persistent lactations are likely to benefit animal welfare through fewer calvings and by placing less emphasis on maximal production at peak lactation, and modelling of persistent lactation with longer calving intervals indicates their likely economic benefits. In these circumstances, there is considerable incentive to elucidate the determinants of mammary apoptosis, and the factors controlling the dynamic balance between cell proliferation and cell death in the lactating mammary gland. 相似文献
979.
Julian Zayas-Arrabal Amaia Alquiza Erkan Tuncay Belma Turan Monica Gallego Oscar Casis 《International journal of molecular sciences》2021,22(13)
Background: Diabetic patients have prolonged cardiac repolarization and higher risk of arrhythmia. Besides, diabetes activates the innate immune system, resulting in higher levels of plasmatic cytokines, which are described to prolong ventricular repolarization. Methods: We characterize a metabolic model of type 2 diabetes (T2D) with prolonged cardiac repolarization. Sprague-Dawley rats were fed on a high-fat diet (45% Kcal from fat) for 6 weeks, and a low dose of streptozotozin intraperitoneally injected at week 2. Body weight and fasting blood glucose were measured and electrocardiograms of conscious animals were recorded weekly. Plasmatic lipid profile, insulin, cytokines, and arrhythmia susceptibility were determined at the end of the experimental period. Outward K+ currents and action potentials were recorded in isolated ventricular myocytes by patch-clamp. Results: T2D animals showed insulin resistance, hyperglycemia, and elevated levels of plasma cholesterol, triglycerides, TNFα, and IL-1b. They also developed bradycardia and prolonged QTc-interval duration that resulted in increased susceptibility to severe ventricular tachycardia under cardiac challenge. Action potential duration (APD) was prolonged in control cardiomyocytes incubated 24 h with plasma isolated from diabetic rats. However, adding TNFα and IL-1b receptor blockers to the serum of diabetic animals prevented the increased APD. Conclusions: The elevation of the circulating levels of TNFα and IL-1b are responsible for impaired ventricular repolarization and higher susceptibility to cardiac arrhythmia in our metabolic model of T2D. 相似文献
980.
Monica Barone Laura Mendozzi Federica DAmico Marina Saresella Simone Rampelli Federica Piancone Francesca La Rosa Ivana Marventano Mario Clerici Alessia dArma Luigi Pugnetti Valentina Rossi Marco Candela Patrizia Brigidi Silvia Turroni 《International journal of molecular sciences》2021,22(13)
Multiple sclerosis (MS) is a neurodegenerative inflammatory condition mediated by autoreactive immune processes. Due to its potential to influence host immunity and gut-brain communication, the gut microbiota has been suggested to be involved in the onset and progression of MS. To date, there is no definitive cure for MS, and rehabilitation programs are of the utmost importance, especially in the later stages. However, only a few people generally participate due to poor support, knowledge, and motivation, and no information is available on gut microbiota changes. Herein we evaluated the potential of a brief high-impact multidimensional rehabilitation program (B-HIPE) in a leisure environment to affect the gut microbiota, mitigate MS symptoms and improve quality of life. B-HIPE resulted in modulation of the MS-typical dysbiosis, with reduced levels of pathobionts and the replenishment of beneficial short-chain fatty acid producers. This partial recovery of a eubiotic profile could help counteract the inflammatory tone typically observed in MS, as supported by reduced circulating lipopolysaccharide levels and decreased populations of pro-inflammatory lymphocytes. Improved physical performance and fatigue relief were also found. Our findings pave the way for integrating clinical practice with holistic approaches to mitigate MS symptoms and improve patients’ quality of life. 相似文献