Towards a low‐cost high‐quality carbon‐nanotube field‐emission display

Abstract— We have developed field‐emission‐display technology driven by chemical‐vapor‐deposition‐grown carbon‐nanotube emitters incorporated in a simple, low‐cost device structure. Here, we report on frit‐sealed test displays with a brightness of 3000 cd/m² at 3 kV and a lifetime of 9000 hours with only 45% degradation. We also demonstrate the scalability of the technology with a uniform high‐brightness 6‐in. QVGA that displays video images with a switching voltage of 40 V.     

The Saccharomyces cerevisiae MFS Superfamily SGE1 Gene Confers Resistance to Cationic Dyes

A gene from Saccharomyces cerevisiae whose overexpression confers resistance to 10-N-nonyl acridine orange (NAO) has been isolated. This cationic dye binds acidic phospholipids and more specifically cardiolipin (Petit, J. M., Maftah, A., Ratinaud, M. H. and Julien, R. Eur. J. Biochem. 209 , 267–273, 1992). The isolated gene was found to be identical to SGE1, a partial multicopy suppressor of the gal11 mutation (Amakasu, H., Suzuki, Y., Nishizawa, M. and Fukasawa, T. Genetics 134 , 675–683, 1993), that also confers crystal violet resistance to a supersensitive strain (Ehrenhofer-Murray, A. E., Wurgler, F. E. and Sengstag, C. Mol. Gen. Genet. 244 , 287–294, 1994). The data presented in this paper show that the SGE1 gene product, a member of the major facilitator superfamily, confers a pleiotropic drug-resistance phenotype when present in high copy number. The results also demonstrate that Sge1p acts as an extrusion permease whose specificity seems restricted to dye molecules possessing a large unsaturated domain that stabilizes a permanent positive charge such as NAO, crystal violet, ethidium bromide or malachite green. © 1997 John Wiley & Sons, Ltd.     

Spheroid Culture Differentially Affects Cancer Cell Sensitivity to Drugs in Melanoma and RCC Models

2D culture as a model for drug testing often turns to be clinically futile. Therefore, 3D cultures (3Ds) show potential to better model responses to drugs observed in vivo. In preliminary studies, using melanoma (B16F10) and renal (RenCa) cancer, we confirmed that 3Ds better mimics the tumor microenvironment. Here, we evaluated how the proposed 3D mode of culture affects tumor cell susceptibility to anti-cancer drugs, which have distinct mechanisms of action (everolimus, doxorubicin, cisplatin). Melanoma spheroids showed higher resistance to all used drugs, as compared to 2D. In an RCC model, such modulation was only observed for doxorubicin treatment. As drug distribution was not affected by the 3D shape, we assessed the expression of MDR1 and mTor. Upregulation of MDR1 in RCC spheroids was observed, in contrast to melanoma. In both models, mTor expression was not affected by the 3D cultures. By NGS, 10 genes related with metabolism of xenobiotics by cytochrome p450 were deregulated in renal cancer spheroids; 9 of them were later confirmed in the melanoma model. The differences between 3D models and classical 2D cultures point to the potential to uncover new non-canonical mechanisms to explain drug resistance set by the tumor in its microenvironment.     

Influence of protein and mineral composition on the formation of whey protein heat-induced microgels

The aim of the present study was to investigate the effect of the initial protein and mineral composition on the formation of whey protein microgels at a protein concentration of 4 wt%. As a model system, both demineralized α-lactalbumin (α-la) and β-lactoglobulin (β-lg) were mixed at 20/80, 50/50 and 80/20 α-la/β-lg ratios and heated (85 °C, 15 min) in the pH range 5.7–6.2. Pure dispersions of α-la were not forming microgels but rather precipitates (12%) and a majority of soluble aggregates (83%). Upon mixing with β-lg, microgels were only obtained for the 20/80 ratio at pH 5.7 or for pure β-lg at pH 5.8. Interestingly, the latter ratio was close to the natural composition occurring in most of the commercial whey protein isolates (WPIs). For higher ratios, particles were more or less aggregated and not spherical. As for α-la alone, most of the denatured proteins formed soluble aggregates. These results might be explained by the fact that α-la reduced the hydrophobic attractive forces involved in microgel formation, shifting the equilibrium towards the soluble aggregates pathway. This assumption was confirmed by the very low surface hydrophobicity of the soluble aggregates determined by ANS binding experiments. The conversion yield from native protein into microgels was about 51% for the 20/80 α-la/β-lg model mixture, whereas it was higher (70–85%) for commercial WPIs under similar experimental conditions. To test the possible effect of the initial mineral composition of the commercial WPIs, these products were demineralized and their ability to form microgels was tested again. After demineralisation, WPIs behaved very similarly to the 20/80 α-la/β-lg model system, the yield of conversion into microgels dropping to about 65% at pH 5.7. It was therefore concluded that in addition to the α-la/β-lg mixing ratio that was controlling hydrophobic interactions between denatured proteins that was accounting for about 50% of the microgel conversion yield, the initial mineral composition of WPIs contributed to another 20–35% yield as it was modulating the repulsive forces between the denatured proteins, promoting aggregation.     

Flexible technologies and smart clothing for citizen medicine, home healthcare, and disease prevention.

Improvement of the quality and efficiency of healthcare in medicine, both at home and in hospital, is becoming more and more important for patients and society at large. As many technologies (micro technologies, telecommunication, low-power design, new textiles, and flexible sensors) are now available, new user-friendly devices can be developed to enhance the comfort and security of the patient. As clothes and textiles are in direct contact with about 90% of the skin surface, smart sensors and smart clothes with noninvasive sensors are an attractive solution for home-based and ambulatory health monitoring. Moreover, wearable devices or smart homes with exosensors are also potential solutions. All these systems can provide a safe and comfortable environment for home healthcare, illness prevention, and citizen medicine.     

Xanthomonas citri pv. citri Pathotypes: LPS Structure and Function as Microbe‐Associated Molecular Patterns

Xanthomonas citri pv. citri is the pathogen responsible for Asiatic citrus canker, one of the most serious citrus diseases worldwide. The lipopolysaccharide (LPS) molecule has been demonstrated to be involved in X. citri pv. citri virulence. Despite enormous progress in investigations of the molecular mechanisms for bacterial pathogenicity, determination of the detailed LPS structure–activity relationship is limited, as the current knowledge is mainly based on structural determination of one X. citri pv. citri strain. As X. citri pv. citri strains are distinguished into three main pathogenicity groups, we characterized the full structure of the LPS from two pathotypes that differ in their host‐range specificity. This revealed an intriguing difference in LPS O‐chain structure. We also tested the LPSs and isolated lipid A moieties for their ability to act as microbe‐associated molecular patterns in Arabidopsis thaliana. Both LPS/lipid As induced ROS accumulation, but no difference was observed between the two pathotypes.     

Synthesis,characterization and bioactivity of bioglasses in the Na2O–CaO–P2O5–SiO2 system prepared via sol gel processing

Different kinds of bioactive materials are used as bone substitutes. In particular, bioglasses containing Si, Ca, Na and P, bind to host tissues with a stable chemical bond. The phenomenon of bioactivity is associated with the formation of a crystallized hydroxycarbonated apatite (HCA) layer on the bioglass surface, when soaked in a simulated physiological fluid. This layer is similar to the mineral phase of bone.     

Interaction between farming systems, riparian zones, and landscape patterns: a case study in western France

We analyze the factors driving land use within and outside riparian zones in four small (about 800 ha) watersheds in Brittany. The results show a difference between riparian and non-riparian zones (less used for grassland), but other factors are also important, such as field size or farm management type. In large farms, small fields are easily abandoned. A multivariate analysis with farm and field characteristics explains 30% of land use variation. Our results suggest that farm type deflects land use from the regional mode, so it is important, in the implementation of environmental zoning, to assess constraints at the farm level.     

End-of-day moods on work and leisure days in relation to extraversion, neuroticism, and amount of change in daily activities.

Tested hypotheses that (a) the relationship between daily activity variation (AV) of Ss and their end-of-day moods (M) is moderated by extraversion-introversion (E-I), the relationship being positive for extraverts and negative for introverts; and (b) the relationships of AV, M, and E-I are stronger on a nonwork (leisure) than a work day (WL). A possible influence of neuroticism-stability (N-S) on the above relationships was also explored. 98 adults were given the Eysenck Personality Inventory and, based on their scores, were placed into 1 of 4 groups (formed by combinations of extraversion or introversion and neuroticism or stability). Ss also completed a time diary for 1 work and 1 nonwork day, indicating their activities, moods, and other information. A 2 * 4 analysis of variance of M scores for the dichotimized classifications of WL, E-I, N-S, and AV supported both hypotheses. Neurotics showed inverted responses from those of stables, such that the positive relationship between AV and M for stable extraverts became negative, and the negative relationship for stable introverts became positive, when Ss were neurotic. A post-hoc formulation to account for results is presented, and there is a discussion of forms of varied experience that leisure days offer. (PsycINFO Database Record (c) 2010 APA, all rights reserved)