A note about the complexity of minimizing Nesterov's smooth Chebyshev–Rosenbrock function

This short note considers and resolves the apparent contradiction between known worst-case complexity results for first- and second-order methods for solving unconstrained smooth nonconvex optimization problems and a recent note by Jarre [On Nesterov's smooth Chebyshev–Rosenbrock function, Optim. Methods Softw. (2011)] implying a very large lower bound on the number of iterations required to reach the solution's neighbourhood for a specific problem with variable dimension.     

Natural Antioxidants in Anemia Treatment

Anemia, characterized by a decrease of the hemoglobin level in the blood and a reduction in carrying capacity of oxygen, is a major public health problem which affects people of all ages. The methods used to treat anemia are blood transfusion and oral administration of iron-based supplements, but these treatments are associated with a number of side effects, such as nausea, vomiting, constipation, and stomach pain, which limit its long-term use. In addition, oral iron supplements are poorly absorbed in the intestinal tract, due to overexpression of hepcidin, a peptide hormone that plays a central role in iron homeostasis. In this review, we conducted an analysis of the literature on biologically active compounds and plant extracts used in the treatment of various types of anemia. The purpose of this review is to provide up-to-date information on the use of these compounds and plant extracts, in order to explore their therapeutic potential. The advantage of using them is that they are available from natural resources and can be used as main, alternative, or adjuvant therapies in many diseases, such as various types of anemia.     

Chemical characterisation of anthocyanins in tamarillo (Solanum betaceum Cav.) and Andes berry (Rubus glaucus Benth.) fruits

The anthocyanin composition of tamarillo (Solanum betaceum Cav., red variety) and Andes berry (Rubus glaucus Benth.) was determined by HPLC–PDA and HPLC–ESIMS. From the anthocyanin-rich extracts (AREs), pure compounds (1–7) were obtained by MLCCC (multilayer countercurrent chromatography) and further preparative HPLC, and their unequivocal structures were obtained by 1D and 2D NMR analyses. The new anthocyanin delphinidin 3-O-α-l-rhamnopyranosyl-(1 → 6)-β-d-glucopyranoside-3′-O-β-d-glucopyranoside, as well as the known cyanidin-3-O-rutinoside, pelargonidin-3-O-rutinoside, and delphinidin-3-O-rutinoside were identified as constituents of tamarillo fruit. Although the anthocyanin composition of Andes berry had been reported before in the literature, the unequivocal structure elucidation of the major compound, cyanidin-3-O-α-l-rhamnopyranosyl-(1 → 6)-O-β-d-xylopyranosyl-(1 → 2)-β-d-glucopyranoside, was achieved for the first time.     

Changes in odour-active compounds of two varieties of Colombian guava (Psidium guajava L.) during ripening

Changes in the concentrations of odour-active compounds in two varieties of Colombian guava (Psidium guajava L.) fruits during ripening were followed by application of stable isotopic dilution analyses (SIDA). The data revealed that, in particular, the concentration of C₆-aldehydes, as well as the amount of the sulphur compounds 3-sulphanylhexyl acetate and 3-sulphanyl-1-hexanol, decreased with ripening, while the concentrations of aliphatic esters and furanones increased during this process. A calculation of odour activity values indicated that although the C₆-aldehydes decreased during ripening, these still made the greatest contribution to the overall aroma at all stages of ripening. Changes in odour-active compounds in white- and pink-fleshed guavas showed the same behaviour.     

Microencapsulation of Andes Berry (Rubus glaucus Benth.) Aqueous Extract by Spray Drying

The Andes berry (Rubus glaucus Benth.), a tropical fruit with a high anthocyanin content and pleasant aroma, was selected for spray drying to produce solids that preserve the sensory characteristics (colour, odour and taste) of the fresh fruit. A factorial design (9?×?2) was implemented to evaluate the influence of the encapsulating agent (maltodextrin DE 20, arabic gum, corn starch, yucca starch, Capsul® TA and Hi-Cap^TM 100, as well as three mixtures of them) and the nozzle diameter (1.0 and 2.0 mm) on the characteristics of solids, anthocyanin content, moisture and water activity. All solids showed water activity values (a _w) between 0.199 and 0.422, and particle size ranging from 3 to 15 μm according to microscopy results. The samples exhibiting the highest anthocyanin content were subjected to a discriminative sensory analysis. The Andes berry microencapsulates obtained with Hi-Cap^TM 100 and maltodextrin DE 20 as wall materials were chosen because of their sensory properties. The release of anthocyanins as well as volatile aroma compounds by water dissolution was confirmed by both liquid and gas chromatography coupled to mass spectrometry (HPLC-MS and GCMS, respectively). The chroma (C*ab) and a* values of the solutions were higher than those of the powders, which indicated a more intense red colour. Thermal analyses (thermogravimetric analyses and differential scanning calorimetry) showed that these two solids were stable up to 100 °C under a nitrogen atmosphere. Remarkably, the anthocyanin content did not change during 180 days at 18 °C and a relative humidity of less than 60 %. However, the shelf life of these products is highly dependent on the humidity during storage because a relative humidity increase causes significant damage to the microcapsule structures and the loss of the encapsulated materials.     

Inhibitory effect of Zizania latifolia chloroform fraction on allergy-related mediator production in RBL-2H3 cells

Food Science and Biotechnology - Zizania latifolia exhibits anti-inflammatory and anti-allergic effects; however, the mechanisms behind these effects are unknown. Here the ethanol extract of Z....     

Multifunctional Silver Nanoparticles-Decorated Silica Functionalized with Retinoic Acid with Anti-Proliferative and Antimicrobial Properties

The paper describes a rapid and simple method for preparing a multifunctional biomaterial based on retinoic acid covalently bound on silica@Ag particles. Monodispersed SiO₂ particles were prepared by Stöber method and further used for loading the Ag nanoparticles on their surface. This composite was further functionalized with retinoic acid. Characterization of the hybrid materials was made by UV–Visible spectroscopy, Transmission electron microscopy, Scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and Thermal analysis. The biological evaluation of the obtained materials revealed their potential use for multiple biomedical applications, from anti-proliferative agents to novel antimicrobial and antibiofilm strategies.     

Sex and Age-Related Differences in Neuroinflammation and Apoptosis in Balb/c Mice Retina Involve Resolvin D1

(1) Background: The pro-resolving lipid mediator Resolvin D1 (RvD1) has already shown protective effects in animal models of diabetic retinopathy. This study aimed to investigate the retinal levels of RvD1 in aged (24 months) and younger (3 months) Balb/c mice, along with the activation of macro- and microglia, apoptosis, and neuroinflammation. (2) Methods: Retinas from male and female mice were used for immunohistochemistry, immunofluorescence, transmission electron microscopy, Western blotting, and enzyme-linked immunosorbent assays. (3) Results: Endogenous retinal levels of RvD1 were reduced in aged mice. While RvD1 levels were similar in younger males and females, they were markedly decreased in aged males but less reduced in aged females. Both aged males and females showed a significant increase in retinal microglia activation compared to younger mice, with a more marked reactivity in aged males than in aged females. The same trend was shown by astrocyte activation, neuroinflammation, apoptosis, and nitrosative stress, in line with the microglia and Müller cell hypertrophy evidenced in aged retinas by electron microscopy. (4) Conclusions: Aged mice had sex-related differences in neuroinflammation and apoptosis and low retinal levels of endogenous RvD1.     

Characterisation and performance assessment of guava (Psidium guajava L.) microencapsulates obtained by spray-drying

The aqueous extract of pink-fleshed guava fruit was encapsulated by spray-drying with maltodextrin (MD), arabic gum (AG), and their mixtures. The use of AG improves the fluidity during the drying process but produces an undesirable residual taste and decreases the thermal stability in the final microencapsulated powders. Retention of some aroma-active guava volatiles in the powders was confirmed by using HS-SPME-GC-MS analyses. The sensory analyses performed by two sets of non-trained panellists (adults and children) allow to select the most promising powders (MD and AGMD-1). They were physicochemically characterised and subjected to thermal (TGA and DSC) and morphologic (SEM) analyses. The successful production of spherical microencapsulates was also confirmed. From a storage stability study at two relative humidity (RH) conditions (74% and 94%), a strong influence of this parameter in the structure stability of microencapsulates and aroma release was found. The solids developed in this study represent an innovative and natural processed product from guava fruits which can be incorporated into different food products due to their sensory properties.