On the moduly of convexity

[EN] It is known that, given a Banach space (X, parallel to center dot parallel to), the modulus of convexity associated to this space delta X is a non-negative function, nondecreasing, bounded above by the modulus of convexity of any Hilbert space and satisfies the equation delta x(epsilon)/epsilon(2) 0 is a constant. We show that, given a function f satisfying these properties then, there exists a Banach space in such a way its modulus of convexity is equivalent to f, in Figiel's sense. Moreover this Banach space can be taken to be two-dimensional.The first author was supported by grants MTM2005-08379 of MECD (Spain), 00690/PI/04 of Fundación Séneca (CARM, Spain), and AP2003-4453 of MECD (Spain).Guirao Sánchez, AJ.; Hajek, P. (2007). On the moduly of convexity. Proceedings of the American Mathematical Society. 135(10):3233-3240. https://doi.org/10.1090/S0002-9939-07-09030-2S323332401351

Schauder bases under uniform renormings

[EN] Let X be a separable superreflexive Banach space with a Schauder basis. We prove the existence of an equivalent uniformly smooth (resp. uniformly rotund) renorming under which the given basis is monotone.First author supported by the grants MTM2005-08379 of MECD (Spain), 00690/PI/04 of Fundación Séneca (CARM, Spain) and AP2003-4453 of MECD (Spain), Second author supported by AV0Z10190503 and A100190502.Guirao Sánchez, AJ.; Hajek, P. (2007). Schauder bases under uniform renormings. Positivity. 11(4):627-638. https://doi.org/10.1007/s11117-007-2067-9S627638114R. Deville, G. Godefroy, V. Zizler, Smoothness and renormings in Banach spaces. Pitman Monographs and Surveys 64, Longman Ed (1993).M. Fabian, P. Habala, P. Hájek, V. Montesinos, J. Pelant, V. Zizler, Functional analysis and infinite dimensional geometry. Canadian Math. Soc. Books, Springer Verlag, (2001).M. Fabian, V. Montesinos, V. Zizler, Smoothness in Banach spaces. Selected problems. Rev. R. Acad. Cien. Serie A Mat. 100, (2006), 101–125.T. Figiel, On the moduli of convexity and smoothness. Studia Math. 56, (1976), 121–155.M. Zippin, A remark on bases and reflexivity in Banach spaces. Isr. J. Math. 6, (1968), 74–79.P. Enflo, Banach spaces which can be given an equivalent uniformly convex norm. Isr. J. Math 13, (1972), 281–288

Strong correlation between the antifungal effect of amphotericin B and its inhibitory action on germ-tube formation in a Candida albicans URA+ strain

The hypothetical capacity of amphotericin B to suppress the formation of germ-tubes, which is the first step of yeast-to-hypha conversion in Candida albicans, has been investigated in the wild-type strain CEY.1 (CAI.4-URA+). Exponential cells exposed to concentrations of amphotericin B below or around the MIC90, exhibited a weak reduction in the percentage of human serum-induced germ-tube formation at 37ºC compared with a non-exposed control. However, the dimorphic transition was drastically suppressed after addition of potentially lethal doses of amphotericin B, which also caused severe cell killing. In contrast, an identical experimental approach carried out with the fungistatic compound 5-fluorocytosine had no significant effect on the level of the germ-tube formation. Together, these results strongly point to a close correlation between the fungicidal action of amphotericin B and its ability to impair morphogenetic conversion in C. albicans. [Int Microbiol 2015; 18(1):25-31]Keywords: Candida albicans · amphotericin B · 5-fluorocytosine · germ-tube · cell killin

Analysis of validamycin as a potential antifungal compound against Candida albicans

Validamycin A has been successfully applied in the fight against phytopathogenic fungi. Here, the putative antifungal effect of this pseudooligosaccharide against the prevalent human pathogen Candida albicans was examined. Validamycin A acts as a potent competitive inhibitor of the cell-wall-linked acid trehalase (Atc1p). The estimated MIC50 for the C. albicans parental strain CEY.1 was 500 mg/l. The addition of doses below MIC50 to exponentially growing CEY.1 cells caused a slight reduction in cell growth. A concentration of 1 mg/ml was required to achieve a significant degree of cell killing. The compound was stable as evidenced by the increased reduction of cell growth with increasing incubation time. A homozygous atc1Δ/atc1Δ mutant lacking functional Atc1p activity showed greater resistance to the drug. The antifungal power of validamycin A was limited compared with the drastic lethal action caused by exposure to amphotericin B. The endogenous content of trehalose rose significantly upon validamycin and amphotericin B addition. Neither serum-induced hypha formation nor the level of myceliation recorded in macroscopic colonies were affected by exposure to validamycin A. Our results suggest that, although validamycin A cannot be considered a clinically useful antifungal against C. albicans, its mechanism of action and antifungal properties provide the basis for designing new, clinically interesting, antifungal-related compounds. [Int Microbiol 2013; 16(4):217-225]Keywords: Candida albicans · Rhizoctonia solani · validamycin A · amphotericin B · trehalos

Analysis of nonlinear compartmental model using a reliable method

The goal of this work is to investigate nonlinear models and their complexity using techniques that are universal and have connections to historical and material aspects. Using the premise of a constant population that is uniformly mixed, a nonlinear compartmental model that depicts the movement between voter classes is taken into consideration. In the current work, we investigate the dynamical framework that supports the interactions between the three parties. It is discussed how rate change affects various metrics. The conditions for boundedness, stability, existence, and other dynamics are obtained. We derive the effects of generalizing the model in any order. The current study supports investigations into complex real-world issues and forecasts of necessary plans. © 2023 The Author(s

Ranges of operators and Derivatives

[EN] We show a unified method of proving the existence of C(1)-Frechet smooth and Lipschitz mappings which are surjective or whose range of the derivative contains the whole dual unit ball. As an application, under Martin's Maximum axiom, we obtain a complete result for those spaces with density character omega(1). (C) 2009 Elsevier Inc. All rights reserved.Research supported by Project MTM2008-05396 and the Universidad Politecnica de Valencia. Research supported by the grants A100190502, IAA 100190801 and Inst. Research Plan AV0Z10190503. Research supported by Project MTM2008-03211 and the Universidad Politecnica de Valencia.Guirao Sánchez, AJ.; Hájek, P.; Montesinos Santalucia, V. (2010). Ranges of operators and Derivatives. Journal of Mathematical Analysis and Applications. 367(1):29-33. https://doi.org/10.1016/j.jmaa.2009.12.010S2933367

Effects of Current and Future Summer Marine Heat Waves on Posidonia oceanica: Plant Origin Matters?

Marine heat waves (MHWs), prolonged discrete anomalously warm water events, have been increasing significantly in duration, intensity and frequency all over the world, and have been associated with a variety of impacts including alteration of ecosystem structure and function. This study assessed the effects of current and futureMHWs on the Mediterranean seagrass Posidonia oceanica performance, also testing the importance of the thermal environment where the plant lives. The effects of current MHWs were studied through a mensurative experiment in a cold and in a warm site (West and North-West Sardinia, Italy, respectively). Future MHWs effects were tested through a manipulative experiment using P. oceanica shoots collected fromthe cold and warmsites and transplanted in a common garden in front of a power plant (North-West Sardinia): here plants were exposed to heat longer in duration and stronger in intensity than the natural MHWs of the last 20 years, resembling the future scenario. Morphological (total # of leaves, maximum leaf length, and percentage of total necrotic leaf length per shoot) and biochemical variables (leaf proteins, carbohydrates, and lipids) were considered. Plants had similar sublethal responses in both the experiments for most of the variables, revealing that current and future MHWs had similar effect types, but different in magnitude depending on the intensity of the waves: in general, the number of leaves, the maximum leaf length and lipid content decreased, while the leaf necrosis and carbohydrates increased. However, also the origin of the plants affected the results, corroborating the hypothesis that the thermal context the plants live affects their tolerance to the heat. Overall, this study provided evidence about the importance of biochemical variations, such as carbohydrate and lipid levels, as potentially good indicators of seagrass heat stress

Effects of Current and Future Summer Marine Heat Waves on Posidonia oceanica: Plant Origin Matters?

Marine heat waves (MHWs), prolonged discrete anomalously warm water events, have been increasing significantly in duration, intensity and frequency all over the world, and have been associated with a variety of impacts including alteration of ecosystem structure and function. This study assessed the effects of current and future MHWs on the Mediterranean seagrass Posidonia oceanica performance, also testing the importance of the thermal environment where the plant lives. The effects of current MHWs were studied through a mensurative experiment in a cold and in a warm site (West and North-West Sardinia, Italy, respectively). Future MHWs effects were tested through a manipulative experiment using P. oceanica shoots collected from the cold and warm sites and transplanted in a common garden in front of a power plant (North-West Sardinia): here plants were exposed to heat longer in duration and stronger in intensity than the natural MHWs of the last 20 years, resembling the future scenario. Morphological (total # of leaves, maximum leaf length, and percentage of total necrotic leaf length per shoot) and biochemical variables (leaf proteins, carbohydrates, and lipids) were considered. Plants had similar sublethal responses in both the experiments for most of the variables, revealing that current and future MHWs had similar effect types, but different in magnitude depending on the intensity of the waves: in general, the number of leaves, the maximum leaf length and lipid content decreased, while the leaf necrosis and carbohydrates increased. However, also the origin of the plants affected the results, corroborating the hypothesis that the thermal context the plants live affects their tolerance to the heat. Overall, this study provided evidence about the importance of biochemical variations, such as carbohydrate and lipid levels, as potentially good indicators of seagrass heat stress.En prens

¿Cómo nos afecta la pérdida de biodiversidad en el planeta? el uso de problemas en una propuesta para futuros profesores de primaria

Este trabajo forma parte de una tesis doctoral que indaga acerca de las concepciones y actitudes sobre la conservación del medio de los futuros maestros, las estrategias educativas que proponen para su desarrollo en Primaria y la posible relación entre ambos aspectos (lo que piensan y saben, y lo que hacen). Dentro de nuestro programa de formación, se ha diseñado la propuesta “¿Cuánta biodiversidad necesitamos para sobrevivir en este planeta?”. Se centra en la adquisición de conocimientos y el desarrollo de competencias ante la pérdida de biodiversidad, y el análisis y discusión de las prácticas educativas más adecuadas para lograr concienciar y cambiar el comportamiento de los alumnos. Se desarrolla en torno a problemas socioambientales cercanos, que atienden sus necesidades formativas como futuros maestros