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1.
J Sci Food Agric ; 101(9): 3767-3777, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33300619

RESUMEN

BACKGROUND: The utilization of Trifolium subterraneum L. cover crops may represent an innovative and efficient option in low-input and organic farming, especially in Mediterranean agroecosystems where low and irregular rainfall require frequent soil tillage and use of herbicides to reduce moisture losses and weed competitiveness. Since imbalances of soil macro- and micro-nutrients due to cover cropping establishment could be responsible for numerous problems in specialized orchards, such as disturbances in the normal tree growth and quality of fruits, the objective of this study was to investigate, the cumulative effects of a 3-years established T. subterraneum cover cropping, compared with a spontaneous flora and a conventional management (as a control), on the levels of mineral nutrients in the apricot leaves and fruits. RESULTS: Our findings indicated that T. subterraneum cover cropping tended to stimulate higher leaf macro- and micro-nutrients content than conventional management and flora spontaneous cover cropping. In addition, the presence of T. subterraneum cover cropping, especially with the incorporation of dead mulches into the soil, increased the content of potassium (K), nitrogen (N), calcium (Ca), iron (Fe) and manganese (Mn) in apricot fruits. CONCLUSION: Taking also into account the effects of T. subterraneum cover cropping on both the reduction of soil weed and enhancement of bacteria communities involved in the soil N-cycle, we may suggest its application in Mediterranean orchards as an eco-friendly alternative to synthetic herbicides for weed control and mineral N fertilizers, while enhancing the apricot tree nutritional status and fruit quality. © 2020 Society of Chemical Industry.


Asunto(s)
Producción de Cultivos/métodos , Frutas/química , Prunus armeniaca/crecimiento & desarrollo , Trifolium/crecimiento & desarrollo , Fertilizantes/análisis , Frutas/crecimiento & desarrollo , Nitrógeno/metabolismo , Estado Nutricional , Prunus armeniaca/química , Suelo/química
2.
J Sci Food Agric ; 99(11): 5219-5228, 2019 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-31049967

RESUMEN

BACKGROUND: The globe artichoke [Cynara cardunculus var. scolymus (L.) Fiori] is a natural source of minerals, fiber, inulin, and polyphenols. A ready-to-cook (RTC) version of this product could improve its commercialization and consumption. In this study, the effects of (i) anti-browning treatments (citric acid 0.5% + ascorbic acid 2%, or cysteine 0.5%, w/v) and (ii) dipping in locust bean gum (LBG) edible coating with or without Foeniculum vulgare essential oil (EO) were evaluated on RTC globe artichoke slices cv. 'Spinoso sardo' during storage (11 days at 4 °C). Fresh weight loss, color, texture, polyphenol oxidase (PPO), microbiological and chemical parameters, antioxidant capacity, and sensory descriptors were determined. RESULTS: The results showed that, despite the antioxidant treatment used, when EO was added to LBG, all microbiological groups underwent an average reduction of 0.50 log CFU g-1 . Cysteine preserved the antioxidant capacity, color, and texture of samples better than citric acid and ascorbic acid, and inhibited PPO; the addition of EO to LBG enhanced these effects. At the end of the storage period, the overall highest sensory attribute score was attained by the coated globe artichoke samples with EO. CONCLUSION: The marked efficacy of the LBG edible coating with added F. vulgare EO in maintaining microbiological, physical, chemical, and sensory qualities makes it a promising processing tool for the preservation of ready-to-cook Spinoso sardo globe artichoke slices during storage for 11 days at 4 °C. © 2019 Society of Chemical Industry.


Asunto(s)
Cynara scolymus/química , Comida Rápida/análisis , Foeniculum/química , Aditivos Alimentarios/análisis , Conservación de Alimentos/métodos , Aceites Volátiles/análisis , Aceites de Plantas/análisis , Color , Culinaria , Conservación de Alimentos/instrumentación , Humanos , Polifenoles/análisis , Gusto
3.
J Sci Food Agric ; 97(2): 650-658, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27144811

RESUMEN

BACKGROUND: Although nitrogen (N) fertilisation is essential for promoting crop yield, it may also affect the produce quality. Here, the influence of three N fertiliser rates (0 kg ha-1 as a control, 200 kg ha-1 and 400 kg ha-1 referred to as N0 , N200 and N400, respectively) on the overall quality of minimally processed globe artichoke heads was investigated during refrigerated storage for 12 days. RESULTS: Throughout the storage time, N fertilised samples had higher inulin contents than those unfertilised. In addition, the respiratory quotient of N200 and N400 samples was 2-fold and 2.5-fold lower than N0 ones, whose values were close to the normal range for vegetables. All the samples reported good microbiological standards, although N200 and N400 achieved lower mesophilic and psychotropic counts than N0 throughout the storage time. After 8 and 12 days of refrigerated storage, the N200 samples showed the highest scores of positive sensory descriptors. CONCLUSION: A fertiliser level of 200 kg N ha-1 is suitable for obtaining minimally processed globe artichoke heads with good nutritional, sensory and microbiological quality, characterised by low endogenous oxidase activities. Proper packaging systems and procedures are, however, crucial for extending the product shelf-life and, thus, promoting its exportation on a wider scale. © 2016 Society of Chemical Industry.


Asunto(s)
Producción de Cultivos , Productos Agrícolas/química , Cynara scolymus/química , Fertilizantes , Flores/química , Calidad de los Alimentos , Ciclo del Nitrógeno , Carga Bacteriana , Catecol Oxidasa/metabolismo , Respiración de la Célula , Productos Agrícolas/crecimiento & desarrollo , Productos Agrícolas/metabolismo , Productos Agrícolas/microbiología , Cynara scolymus/crecimiento & desarrollo , Cynara scolymus/metabolismo , Cynara scolymus/microbiología , Carbohidratos de la Dieta/análisis , Flores/crecimiento & desarrollo , Flores/metabolismo , Flores/microbiología , Manipulación de Alimentos , Almacenamiento de Alimentos , Bacterias Gramnegativas/crecimiento & desarrollo , Bacterias Gramnegativas/aislamiento & purificación , Bacterias Grampositivas/crecimiento & desarrollo , Bacterias Grampositivas/aislamiento & purificación , Inulina/análisis , Inulina/biosíntesis , Valor Nutritivo , Pigmentos Biológicos/análisis , Pigmentos Biológicos/biosíntesis , Pigmentos Biológicos/metabolismo , Proteínas de Plantas/metabolismo , Refrigeración , Sensación , Propiedades de Superficie
4.
BMC Ophthalmol ; 15: 185, 2015 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-26711893

RESUMEN

BACKGROUND: Glaucoma is an optic neuropathy characterized by retinal ganglion cells (RGC) loss and retinal nerve fiber layer (RNFL) injury: this results in functional and morphological changes. The first can be observed by Standard Automated Perimetry (SAP), the second by Optic Coherence Tomography (OCT) that measures the RNFL and ganglion cell complex (GCC) thicknesses. Nevertheless, diagnosis of early glaucoma may be difficult. Recently, Medeiros et al. derived an empirical formula combining the measurement of structural and functional tests to provide an estimate of RGC. The aim of the current study is to analyse the correlation between RGC count, estimated by Medeiros' formula, and the structural and functional parameters in patients examined for glaucoma and to evaluate SAP, OCT and RGC counts capability to discriminate the weight of the disease itself. METHODS: Ninety four eyes of 50 consecutive patients clinically referring to glaucoma service of the Universitary Eye Clinic were submitted to a complete ophthalmic evaluation including SAP and Spectral Domain OCT (SD-OCT) of RNFL and macular GCC. Average thickness of RNFL and macular GCC, parameters Global Loss Volume (GLV) and Focal Loss Volume (FLV) over the entire GCC map were taken into account. Estimates of RGC were obtained with the help of a model already published by Medeiros et al. combining light sensitivities from SAP and retinal thickness from OCT. The RGC count was estimated in the entire visual field (central 24°) and in the GCC macular area and then compared with functional and morphological parameters applying Pearson's correlation coefficient. RESULTS: After the classification of the patients by the Glaucoma Staging System 2 of Brusini, we noticed a good correlation among the functional parameters considered, even if the Visual Field Index is unable to identify early glaucoma. An analogous result can be observed for structural data (RNFL and GCC). The correlation detected between functional and structural parameters was moderate. Great differences in RGC counts were found between groups at various stages of glaucoma. GLV showed highest level of correlation (r > -0.8) with RCG counts. CONCLUSIONS: Estimate circumpapillary and macular RGC counts can discriminate various stages of the disease and there is also a good/very good correlation with both functional and structural parameters. GLV could be used instead of RGC counts in clinical practice.


Asunto(s)
Glaucoma de Ángulo Abierto/diagnóstico , Fibras Nerviosas/patología , Enfermedades del Nervio Óptico/diagnóstico , Células Ganglionares de la Retina/patología , Anciano , Recuento de Células , Femenino , Glaucoma de Ángulo Abierto/clasificación , Glaucoma de Ángulo Abierto/fisiopatología , Gonioscopía , Humanos , Presión Intraocular/fisiología , Masculino , Persona de Mediana Edad , Hipertensión Ocular/diagnóstico , Hipertensión Ocular/fisiopatología , Tomografía de Coherencia Óptica , Tonometría Ocular , Pruebas del Campo Visual , Campos Visuales/fisiología
5.
Phys Rev Lett ; 113(3): 034101, 2014 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-25083646

RESUMEN

We report and discuss analytical solutions of the vector nonlinear Schrödinger equation that describe rogue waves in the defocusing regime. This family of solutions includes bright-dark and dark-dark rogue waves. The link between modulational instability (MI) and rogue waves is displayed by showing that only a peculiar kind of MI, namely baseband MI, can sustain rogue-wave formation. The existence of vector rogue waves in the defocusing regime is expected to be a crucial progress in explaining extreme waves in a variety of physical scenarios described by multicomponent systems, from oceanography to optics and plasma physics.

6.
Phys Rev Lett ; 111(11): 114101, 2013 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-24074089

RESUMEN

We introduce a novel family of analytic solutions of the three-wave resonant interaction equations for the purpose of modeling unique events, i.e., "amplitude peaks" which are isolated in space and time. The description of these solutions is likely to be a crucial step in the understanding and forecasting of rogue waves in a variety of multicomponent wave dynamics, from oceanography to optics and from plasma physics to acoustics.

7.
Foods ; 12(21)2023 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-37959067

RESUMEN

The relationship between fruit position, ripening stage, and variety has not been well studied in pepper plants. To understand the interaction of these factors, a diversity of phytochemical traits as well as antioxidant activity were investigated with agronomic traits in eleven hot pepper varieties collected from the upper and lower parts of the plant and harvested at three maturity stages (green, orange, and red). Capsaicin content (CAP) showed a relatively high genetic effect; on the contrary, total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activity were more affected by the ripening stage and fruit position. The CAP values ranged from 0.29 ('FKbM') to 0.77 ('Bka') mg CAP equivalents g-1 DW. The ripening stage was the predominant factor for TPC, TFC, DPPH, and FRAP. There was no significant interaction between A × FP, A × RS, and FP × RS for all agro-morphological fruit traits. Variety, fruit position, and ripening stage effects are more significant than all interactions calculated. Lower fruit positions in all samples showed a maximum fruit size, whereas phytochemical traits and yield per plant were relevant in the upper parts, and Phytochemical traits and yield per plant were significantly correlated. From PCA and cluster analysis, all varieties showed the highest biochemical and antioxidant levels with moderate fruit size, except the 'Bel' variety that showed the smallest fruit traits with high yields, and the 'FKbM' and 'FKbK' varieties that showed the highest fruit size but low yields. This study supplies information to identify interesting cultivars with considerable levels of bioactive and phytochemical metabolites, which is useful for breeding programs of novel varieties.

9.
Plants (Basel) ; 11(14)2022 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-35890480

RESUMEN

Increasing interest has been shown in globe artichoke for pharmaceutical and food applications as a significant source of polyphenol compounds. With the aim to improve the polyphenol profile of globe artichoke, an open-field experiment is set up to study the effect of gibberellic acid (GA3) application on the cynaropicrin, caffeoylquinic acid and flavone levels of three genotypes ('Apollo', 'Tema 2000' and 'Violet de Provence'), along with crop earliness, yield and bio-morphological plant response. The results indicate that GA3 treatment is more effective in terms of total polyphenol and caffeoylquinic acid accumulation in 'Apollo', regardless of the plant parts analyzed. In particular, the leaves of 'Apollo' were the richest source of luteolin derivatives of 5-O- and 1,5-di-O-caffeoylquinic acids. On average across the genotypes, GA3 treatment favored the accumulation of apigenin derivatives in the floral stem, and caffeoylquinic acid and cynaropicrin in the leaves. From the perspective of yield, GA3 treatment allowed us to anticipate the first harvest in each genotype, while either maintaining ('Apollo', 'Violet de Provence') or enhancing ('Tema 2000') the fresh weight yield. In conclusion, this study could be interesting for promoting GA3 usage to ameliorate the globe artichoke nutraceutical profile and to anticipate the first harvest for fresh marketing without significant yield losses.

10.
Plants (Basel) ; 11(8)2022 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-35448748

RESUMEN

Durum wheat is one of the largest cultivated crops across Mediterranean areas. The high demand for sustainable crop productions, especially concerning weed management, is driving the return to local landraces. In the present work, the in vitro allelopathic effects of the extracts of three durum wheat landraces ('Timilia', 'Russello' and 'Perciasacchi') and a modern variety ('Mongibello'), obtained from three different plant parts (ears, stems and roots), were tested on seed germination (G) and mean germination time (MGT) of Portulaca oleracea L. and Stellaria. media (L.) Vill., two weeds commonly infesting wheat fields. In addition, the total polyphenol (TPC) and total flavonoid (TFC) content of extracts was determined. All extracts reduced G and increased MGT in both weeds compared to the control. The magnitude of phytotoxicity was strongly affected by the influence of genotype, plant part and extract dilution. Overall, the landraces 'Timilia' and 'Russello' showed the highest allelopathic effects, ear extracts were the most active, and the maximum extract dilution induced higher phytotoxicity. Extracts' TPC and TFC corroborated these results. The findings obtained here encourage the use of local landraces as a source of allelochemicals and suggest that they could be left on soil surface or soil-incorporated after harvest for a possible weed control.

11.
BMJ Open ; 12(6): e059309, 2022 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-35710248

RESUMEN

OBJECTIVES: To provide estimates for how different treatment pathways for the management of severe aortic stenosis (AS) may affect National Health Service (NHS) England waiting list duration and associated mortality. DESIGN: We constructed a mathematical model of the excess waiting list and found the closed-form analytic solution to that model. From published data, we calculated estimates for how the strategies listed under Interventions may affect the time to clear the backlog of patients waiting for treatment and the associated waiting list mortality. SETTING: The NHS in England. PARTICIPANTS: Estimated patients with AS in England. INTERVENTIONS: (1) Increasing the capacity for the treatment of severe AS, (2) converting proportions of cases from surgery to transcatheter aortic valve implantation and (3) a combination of these two. RESULTS: In a capacitated system, clearing the backlog by returning to pre-COVID-19 capacity is not possible. A conversion rate of 50% would clear the backlog within 666 (533-848) days with 1419 (597-2189) deaths while waiting during this time. A 20% capacity increase would require 535 (434-666) days, with an associated mortality of 1172 (466-1859). A combination of converting 40% cases and increasing capacity by 20% would clear the backlog within a year (343 (281-410) days) with 784 (292-1324) deaths while awaiting treatment. CONCLUSION: A strategy change to the management of severe AS is required to reduce the NHS backlog and waiting list deaths during the post-COVID-19 'recovery' period. However, plausible adaptations will still incur a substantial wait to treatment and many hundreds dying while waiting.


Asunto(s)
Estenosis de la Válvula Aórtica , COVID-19 , Estenosis de la Válvula Aórtica/cirugía , Humanos , Modelos Teóricos , Medicina Estatal , Listas de Espera
12.
J Sci Food Agric ; 91(2): 302-8, 2011 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-20954162

RESUMEN

BACKGROUND: The globe artichoke is an important vegetable, widely consumed in the Mediterranean Basin, and is spreading also to other parts of the world. The mineral profile of globe artichoke has been very little investigated. The purpose of this work was to evaluate the content of some essential macrominerals (Na, K, Ca, Mg) and microminerals (Fe, Cu, Mn, Zn) in nine genotypes of globe artichoke in relation to different head parts (bracts and receptacle), locations and seasons. RESULTS: The mineral profile was significantly affected by genotype, head fraction, location and season. Great variation was found among studied genotypes. 'Blanc Hyerois', Harmony F1', 'Madrigal F1' and 'Violetto di Provenza' showed high levels of both macro- and micromineral content. In particular, these, as well as other genotypes, had a higher content in the receptacle (edible part) than in the bracts. The globe artichoke had a high level of K and mainly, compared to some vegetables, low Na/K ratio, which is important in preventing hypertension and cardiovascular diseases. CONCLUSIONS: The results obtained partially improve the lack of data in the literature and this knowledge could be used to develop different crop managements and/or breeding programmes to improve the mineral composition, and thereby enhance human nutrition and health.


Asunto(s)
Cynara scolymus/química , Ambiente , Genotipo , Inflorescencia , Minerales/análisis , Oligoelementos/análisis , Cynara scolymus/genética , Estaciones del Año , Especificidad de la Especie
13.
Plant Foods Hum Nutr ; 66(3): 291-7, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21792680

RESUMEN

The globe artichoke is a widely consumed vegetable in the Mediterranean Basin, with Italy being the leading producer. In southern Italy, its cultivation contributes to local economic stability and social development. The producers are increasingly choosing to replace autochthonous varieties, such as 'Violetto di Sicilia', with cultivars bred or selected outside of the region, putting pressure on the maintenance of traditional varieties. Here, we have undertaken a detailed morphological and chemical analysis of a group of clones selected from a population of 'Violetto di Sicilia'. All the traits measured displayed genetic variation, particularly the total content of phenolics and minerals. The capitula of the 'Violetto di Sicilia' clones contained, on average, 6.3 g kg(-1) of fresh weight total phenolics, compared with 4.5 g kg(-1) in the two commercial varieties. The clones also had more inulin than commercial varieties (254 vs. 225 g kg(-1) of dry matter), as well as a good mineral content. The set of clones is of interest in the context of the proposed improvement of the crop through breeding and selection of genotypes with high nutritional quality and a specific end-use (industrial processing or fresh consumption).


Asunto(s)
Cynara scolymus/química , Variación Genética , Inulina/análisis , Minerales/análisis , Fenoles/análisis , Comercio , Cynara scolymus/anatomía & histología , Cynara scolymus/genética , Genotipo
14.
Proc Math Phys Eng Sci ; 477(2252): 20210408, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35153577

RESUMEN

We consider the propagation of short waves which generate waves of much longer (infinite) wavelength. Model equations of such long wave-short wave (LS) resonant interaction, including integrable ones, are well known and have received much attention because of their appearance in various physical contexts, particularly fluid dynamics and plasma physics. Here we introduce a new LS integrable model which generalizes those first proposed by Yajima and Oikawa and by Newell. By means of its associated Lax pair, we carry out the linear stability analysis of its continuous wave solutions by introducing the stability spectrum as an algebraic curve in the complex plane. This is done starting from the construction of the eigenfunctions of the linearized LS model equations. The geometrical features of this spectrum are related to the stability/instability properties of the solution under scrutiny. Stability spectra for the plane wave solutions are fully classified in the parameter space together with types of modulational instabilities.

15.
Foods ; 10(3)2021 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-33801354

RESUMEN

Two globe artichoke genotypes, "Spinoso sardo" and "Opera F1", have been processed as ready-to-cook (RTC) slices and refrigerated at 4 °C for 12 days (i) to evaluate the suitability to be processed as RTC slices; (ii) to evaluate the effect of a Foeniculum vulgare essential oil (EO) emitter, within an active package system, to delay quality decay, thus extending shelf life; (iii) to estimate the impact of EO emitter on the sensory profile of the RTC slices after cooking. Results revealed that both globe artichoke genotypes possess a good attitude to be processed as RTC product. "Opera F1" showed the best performances for color parameters, texture and chemical indexes, while "Spinoso sardo" showed lower mass loss (ML) over the storage time. The addition of EO emitter slowed down the consumption of O2, better preserved texture when compared to the control and more effectively control polyphenol oxidase (PPO) activity and antioxidants' retention during the cold storage. Microbial counts in control globe artichoke RTC slices were significantly higher than those packed with EO emitter, confirming the inhibiting role played by EO of F. vulgare. In addition, the EO emitter did not influence negatively the sensory profile of RTC globe artichoke slices after microwave cooking.

16.
Plants (Basel) ; 9(11)2020 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-33172153

RESUMEN

Cover crops are gaining in popularity as an eco-friendly tool for weed control in organic and low-input agricultural systems. A 5-year study was carried out in a Mediterranean environment (Sicily, south Italy) to (1) quantify cover crop biomass production and (2) evaluate the effects on weed soil seed bank, aboveground biomass, species richness, species composition and associations between communities. Cover crop treatments included subterranean clover (Trifolium subterraneum L.) and spontaneous flora, both with and without burying dead mulch into the soil, compared to a conventional management treatment. Weed biomass was significantly reduced by subterranean clover, contrariwise to spontaneous flora, with season-dependent results. Cover crop biomass, which ranged from 44 to more than 290 g DW m-2, was negatively correlated to weed biomass. Moreover, subterranean clover decreased the size of the soil seed bank and species richness. Based on relative frequency, a low similarity was found between the conventional management and cover crop treatments. In addition, no significant differences in species composition across treatments were observed, whereas principal component analysis highlighted some associations. The results suggest that subterranean clover cover cropping is a good option for weed management in Mediterranean agroecosystems.

17.
Am J Infect Control ; 47(3): 271-279, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30392995

RESUMEN

BACKGROUND: We describe the investigation undertaken and the measures adopted to control a Serratia marcescens outbreak in the neonatology unit of La Paz University Hospital in Madrid, Spain. METHODS: Weekly rectal and pharyngeal screenings for S marcescens were performed in the neonates starting after detection of the outbreak. Environmental samples and samples from health care workers (HCWs) were obtained for microbiological analysis. An unmatched case-control study was carried out to investigate risk factors for infection/colonization. RESULTS: The outbreak began in June 2016 and ended in March 2017, affecting a total of 59 neonates. Twenty-five (42.37%) neonates sustained an infection, most frequently conjunctivitis and sepsis. Multivariate logistic regression identified the following risk factors: parenteral nutrition (odds ratio [OR], 103.4; 95% confidence interval [CI], 11.9-894.8), history of previous radiography (OR, 15.3; 95% CI, 2.4-95.6), and prematurity (OR, 5.65; 95% CI, 1.5-21.8). Various measures were adopted to control the outbreak, such as strict contact precautions, daily multidisciplinary team meetings, cohorting, allocation of dedicated staff, unit disinfection, and partial closure. Hands of HCWs were the main suspected mechanism of transmission, based on the inconclusive results of the environmental investigation and the high number of HCWs and procedures performed in the unit. CONCLUSIONS: S marcescens spreads easily in neonatology units, mainly in neonatal intensive care units, and is often difficult to control, requiring a multidisciplinary approach. Strict measures, including cohorting and medical attention by exclusive staff, are often needed to get these outbreaks under control.


Asunto(s)
Brotes de Enfermedades , Transmisión de Enfermedad Infecciosa/prevención & control , Control de Infecciones/organización & administración , Infecciones por Serratia/epidemiología , Infecciones por Serratia/prevención & control , Estudios de Casos y Controles , Microbiología Ambiental , Femenino , Departamentos de Hospitales , Humanos , Recién Nacido , Control de Infecciones/métodos , Masculino , Técnicas Microbiológicas , Faringe/microbiología , Embarazo , Recto/microbiología , Factores de Riesgo , Serratia marcescens/aislamiento & purificación , España/epidemiología , Centros de Atención Terciaria
18.
J Nonlinear Sci ; 28(4): 1251-1291, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30008518

RESUMEN

It is well known that the linear stability of solutions of 1+1 partial differential equations which are integrable can be very efficiently investigated by means of spectral methods. We present here a direct construction of the eigenmodes of the linearized equation which makes use only of the associated Lax pair with no reference to spectral data and boundary conditions. This local construction is given in the general N×N matrix scheme so as to be applicable to a large class of integrable equations, including the multicomponent nonlinear Schrödinger system and the multiwave resonant interaction system. The analytical and numerical computations involved in this general approach are detailed as an example for N=3 for the particular system of two coupled nonlinear Schrödinger equations in the defocusing, focusing and mixed regimes. The instabilities of the continuous wave solutions are fully discussed in the entire parameter space of their amplitudes and wave numbers. By defining and computing the spectrum in the complex plane of the spectral variable, the eigenfrequencies are explicitly expressed. According to their topological properties, the complete classification of these spectra in the parameter space is presented and graphically displayed. The continuous wave solutions are linearly unstable for a generic choice of the coupling constants.

19.
Found Comut Math ; 17(4): 987-1035, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-32025229

RESUMEN

The paper presents the complete classification of Automorphic Lie Algebras based on sl n ( C ) , where the symmetry group G is finite and acts on sl n ( C ) by inner automorphisms, sl n ( C ) has no trivial summands, and where the poles are in any of the exceptional G-orbits in C ¯ . A key feature of the classification is the study of the algebras in the context of classical invariant theory. This provides on the one hand a powerful tool from the computational point of view; on the other, it opens new questions from an algebraic perspective (e.g. structure theory), which suggest further applications of these algebras, beyond the context of integrable systems. In particular, the research shows that this class of Automorphic Lie Algebras associated with the T O Y groups (tetrahedral, octahedral and icosahedral groups) depend on the group through the automorphic functions only; thus, they are group independent as Lie algebras. This can be established by defining a Chevalley normal form for these algebras, generalising this classical notion to the case of Lie algebras over a polynomial ring.

20.
Food Res Int ; 100(Pt 2): 95-99, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28888464

RESUMEN

Globe artichoke is a proven source of various minerals (such as K, Fe and Zn) in the Mediterranean diet, but their content in response to fertilizer regime has not yet been investigated sufficiently. Thus, we monitored the effect of two contrasting nitrogen/phosphorus/potassium (NPK) fertilizer regimes (one balanced and the other excessive) on the minerals accumulation of 'Apollo' and 'Tema 2000' cultivars, grown in three Sicilian locations ('Landolina', 'Iannarello' and 'Zotto') - South Italy. Except for total nitrogen, the balanced fertilizer regime favoured the accumulation of both macro- and micro-minerals, but with a different extent depending especially on trial location. Particularly, plants grown at 'Iannarello' responded more strongly to the fertilizer regime with respect to K, P, Ca, Fe and Zn accumulation, as a result of its different soil characteristics than the other locations. Providing a balanced supply of nitrogen/phosphorus/potassium via fertilization can enhance the nutritive value of globe artichoke, but taking into account especially soil characteristics.


Asunto(s)
Cynara scolymus/química , Fertilizantes/análisis , Oligoelementos/análisis , Análisis de los Alimentos , Italia , Nitrógeno/análisis , Fósforo/análisis , Potasio/análisis , Suelo/química
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