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Separately and in combination a marine yeast Debaryomyces hansenii and a marine bacterium Stenotrophomonas rhizophila were evaluated for their biocontrol potential against Fusarium proliferatum on muskmelon fruit. The results show that the mixture of yeast and bacterium in vitro reduced the growth of F. proliferatum, possibly due to either by direct parasitism, nutrient competition, lytic enzymes, biosurfactants and/or volatile organic compounds (VOCs). Disease incidence and lesion diameter caused by F. proliferatum on muskmelon was reduced significantly, especially when fruit was inoculated with the mixture of D. hansenii + S. rhizophila. These results indicated that D. hansenii, S. rhizophila and their combination treatments were effective for the postharvest biocontrol of fruit rot on muskmelon.

Variable angle-infrared spectroscopic ellipsometry is proposed as a reliable tool for the characterization of heritage photographic prints. It is shown that the proposed technique has access to both the chemical composition and the physical structure of the photograph. In particular, the physical structure can be determined by interference related spectral oscillations and the behavior, for different angles of incidence, of the peaks corresponding to different chemical components. Emphasis is made on gelatin/baryta samples, and particularly, in the role of the baryta layer. A relatively simple model is used to simulate the ellipsometric spectra. It shows that the thickness and location of different layers in photographic prints can be assessed by optical means.

In this work, we explore the use of confocal microscopy to identify the composition of ancient photographs, taking advantage of the binders’ fluorescence and the organic materials nature used as protective coating in their respective manufacture processes. At the same time, the feasibility of using confocal technologies for the analysis of different photographic strata has been proposed. It is found that such technique provides relevant information about morphological features of the photographic surface as well as on the inner layers; thus, confocal microscopy provides useful images on the stratigraphic structure of photographs. In that sense, the technique is capable to determine the binder nature, the presence of intermediate layers such baryta layer, the presence of protective organic coating on photographic surface and inferred print typologies.

The appropriate selection of adequate primary packaging, such as the glass vial, rubber stopper, and crimp cap for parenteral products is of high importance to ensure product stability, microbiological quality (integrity) during storage as well as patient safety. A number of issues can arise when inadequate vial material is chosen, and sole compliance to hydrolytic class I is sometimes not sufficient when choosing a glass vial. Using an appropriate pre-treatment, such as surface modification or coating of the inner vial surface after the vial forming process the glass container quality is often improved and interactions of the formulation with the surface of glass may be minimized. This study aimed to characterize the inner surface of different type I glass vials (Exp33, Exp51, Siliconized, TopLyo™ and Type I plus®) at the nanoscale level. All vials were investigated topographically by colorimetric staining and Scanning Electron Microscopy (SEM). Glass composition of the surface was studied by Time-of-Flight - Secondary Ion Mass Spectrometry (ToF-SIMS) and X-ray Photoelectron Spectroscopy (XPS), and hydrophobicity/hydrophilicity of the inner surface was assessed by dye tests and surface energy measurements. All containers were studied unprocessed, as received from the vendor, i.e. in unwashed and non-depyrogenized condition. Clear differences were found between the different vial types studied. Especially glass vials without further surface modifications, like Exp33 and Exp51 vials, showed significant (I) vial-to-vial variations within one vial lot as well as (II) variations along the vertical axis of a single vial when studying topography and chemical composition. In addition, differences and heterogeneity in surface energy were found within a given tranche (circumferential direction) of Exp51 as well as Type I plus® vials. Most consistent quality was achieved with TopLyo™ vials. The present comprehensive characterization of surface properties of the different vial types may serve as basis to further guide the selection of adequate primary packaging based on the desired quality target product profile and to support studies of glass surface interactions with formulations. The proposed analytical method panel can be used for characterization of future glass vials either before delivery to the manufacturer or drug product manufacturing.

Glass delamination is characterized by the dissociation of glass flakes from the glass surface. Since glass delamination is time dependent, 5 vial types were investigated to assess delamination under accelerated stress conditions published as quick tests in literature and compared to stress testing recommended per United States Pharmacopoeia1660. A broad panel of analytical techniques was employed to test the solution for visible/subvisible particles and leachables and characterize topography and composition of the surface. The vial types showed significant differences in surface durability when applying the same stress conditions. An increase in glass leachables and change in topography were shown for uncoated vials. An indication for an elevated delamination risk was confirmed for Expansion 33 vials only by the compiled analytical data set including particle assessment and change in elemental composition of the near glass surface investigated by dynamic secondary ion mass spectrometry. The delamination test protocols differ in test solution, handling, and time. Before choosing the most appropriate protocol to predict delamination propensity and mimic real-time conditions, long-term storage data are needed. A combination of analytical techniques to study the risk for long-term corrosion of glass is highly recommended covering the 3 aspects: visible/subvisible particle assessment, solution analysis, and surface characterization.

Ethnobotany is an adequate tool to identify the most import wild edible plants used by local people and to develop strategies for its sustainable use and policy making. This research records the wild edible plants used by the inhabitants of the Sierra la Laguna Biosphere Reserve, in Mexico, and identified priority species for sustainable development. The employed quantitative approach included the application of a food-oriented index named Food Significance Index (FSI), which integrated cultural, agricultural and food parameters; moreover, it used multivariate analysis to identify priority edible species for use and/or conservation. Fifty taxa were identified as the most important wild edible plants in the reserve, integrated into five priority groups. Foods in priority group 1 had the highest culinary diversity by grouping three fruits (Ficus petiolaris, Stenocereus thurberi, and Cyrtocarpa edulis), one almond-like seed (Cnidoscolus maculatus), one vegetable (Matelea cordifolia), and one condiment (Capsicum annuum). Priority groups 2-5 were selective for one or two types of food, such as fruits, teas, or seeds. Since group 1 was the most diverse, the FSI and the employed strategy permitted to identify the priority wild edible plant species with the highest potential for food security. The selected six species should be included in the future management program of the reserve as the priority wild edible plants to develop strategies for conservation, sustainable use, and improvement of the local population income. General policies to manage the selected six species are outlined.

This study deals on the natural degradation of paper monitored by using laser induced fluorescence. Samples of aged paper dated from 1730 to 2009 were analyzed in the spectral region from 540 to 750 nm. A structural evolution of the paper has been detected through variations of the fluorescence spectra characteristics. Results indicate that changes ascribed to the paper fibers as cellulose, hemicellulose and lignin, can be monitored in function of their natural aging time. Therefore, fluorescence spectroscopy is an appropriate technique to investigate the degree of paper deterioration. Furthermore, the emission spectrum allows to estimate their manufacture date.

Today, acrylic emulsion paint is widely used in the artistic area as an alternative to the traditional oil painting. However, after a short time of painting exposure to the environment, the acrylic tends to accumulate surface dirt for inherent reasons to its composition. This phenomenon creates a conservation problem, because the usual cleaning methods are hindered by the acrylic film soft morphology and its high sensitivity to organic solvents. To date, few aqueous solutions based cleaning systems have been investigated as alternatives to the traditional methods. This paper proposes the use of oxalic and tartaric acid solutions for acrylic paints cleaning as alternatives to citric acid. A series of titanium white acrylic paint films were subjected to immersion tests in different aqueous solutions and their weight change was monitored to determine the effects produced by the solutions according to pH (3.5, 5 and 8.5) and conductivity (4, 6 and 12 mS cm−1). Fourier transform infrared spectroscopy with attenuated total reflectance (FTIR-ATR), X-ray diffraction (XRD), and scanning electron microscopy (SEM-EDX) techniques were used to evaluate the acids effects on the films before and after the tests. The results obtained showed that oxalic and tartaric acids exhibit similar properties to citric acid, resulting as a valid alternative for aqueous cleaning treatments on acrylic paintings.

Because the high biodiversity of Mexico about 12% of the country's total area is included as a Natural Protected Areas (NPAs); however, in the last years, according to the official data, an astonishing number of mining concessions covering 28% of the total area of the country has been granted already. The objective of this work is to quantify the geographical overlap of mining concessions with the federal NPAs of Mexico including the exploration/exploitation status of minerals to be extracted. We use geo-referenced polygons of the NPAs and those of mining exploration and exploitation concessions until 2010 and calculated their overlap extension with the application of ArcView GIS 3.3 (ESRI; Redland, CA, U.S.A.). Our results showed that a total of 1609 mining concessions covering an area of 1,486,433 ha geographically overlaps with the NPAs. With the exception of Natural Monuments (NM), all the different categories of NPAs in Mexico showed mining concessions; 75% of Natural Resources Protection Area (NRPA); 63% of Biosphere Reserve (BR); 47% of Protected Area for Flora and Fauna (PAFF); 22% of Sanctuary (S); and 15% of National Park (NP). The impacts of metal mining activities on NPAs are not only limited to biodiversity and affectation to human communities, but they also have a radius of influence not yet evaluated since most of the NPAs have a special role in supplying watersheds and aquifers. Obviously, currently in Mexico a NPA decree does not represent an obstacle to megamining projects; in consequence, their real environmental impacts are underestimated. It is a priority to legally support canceling the mining concessions already granted in the NPAs and stop granting new ones in the future. In the proportion to which environmental authorities continue to openly accept mining concessions within the NPAs, through modifying management programs that allow these activities, they may cause a significant increase in rejections of local people toward the changes in management programs and on the promotion of new NPAs in Mexico.

Multiple sclerosis (MS) is a complex immune-mediated disease. It has been suggested that genetic factors could explain differences in the prevalence among ethnic groups. To know whether genetic ancestry is a potential risk factor for MS in Mexican patients and to identify candidate genes for the susceptibility to the disease we conducted an initial trial of genome-wide analysis.29 patients with diagnosis of definitive MS and 132 unrelated healthy controls were genotyped using the Affymetrix human 6.0 array. After QC procedures, ancestry determination and a preliminary case-control association study were performed.We identified significant differences in the European ancestry proportion between MS cases and controls (33.1 vs. 25.56, respectively; p=0.0045). Imputation analysis in the MHC region on chromosome 6 showed a signal with a significant level (p0.00005) on the HLA-DRB region. Additionally, a preliminary association analysis highlighted the ASF1B as novel candidate gene participating in MS.Our data suggest that European ancestry is a risk factor to develop MS in Mexican Mestizo population. Conversely, indigenous ancestry of Asian origin seems to confer protection. Further studies with more MS cases are needed to confirm these findings.

The aim of this research was to investigate the effect of two different production systems, open-field and shade-enclosure, and four gypsum doses, to find the best environmental option in terms of physiological, morphometric characteristics and with optimum yield in two crops, oregano and thyme in Baja California Sur, Mexico. One cultivar of oregano and one of thyme were grown in shade-enclosure and open-field environments and evaluated for photosynthetic rate, transpiration rate, stomatal conductance, chlorophyll, leaf area, fresh and dry biomass and yield. The results showed significant differences between environmental conditions, crops and their interaction. Gypsum doses had no significant effect on any of the variables measured. For both species shade-enclosure variables measured were more favorable than open-field. In general, of the two crops, oregano performed better than thyme under shade-enclosure conditions, except for Chl a, b, total and leaf water potential which were higher in thyme.

Ordered mesoporous carbons (OMCs) with embedded metallic nickel (Ni) nanoparticles have been directly synthesized by a simple and low temperature (50 °C) hydrothermal method. The synthesis involved the use of a triblock copolymer Pluronic F127 as the mesostructure directing agent, resorcinol (R) and formaldehyde (F) as carbon precursors, and Ni(NO 3 ) 2 ·6H 2 O as nickel source. It consisted in the self-assembly of F127, Ni 2+ salt and RF polymer in an acidic medium and further carbonization, where the Ni 2+ was captured by the network of F127/RF and further reduced into metallic Ni nanoparticles. The resultant Ni/carbon materials were characterised by X-ray diffraction, thermogravimetric analysis, transmission electron microscopy and nitrogen sorption. Ni/carbon materials with a highly ordered mesostructure were obtained using equal moles of resorcinol and formaldehyde molar ratio (R/F = 1/1), whereas an excess amount of formaldehyde (R/F = 1/2) was found to not form an ordered carbon structure. The results showed that nickel particles, with sizes of ∼10–50 nm, were homogeneously dispersed in the carbon matrices, while the pore mesostructure remained intact. The homogeneous Ni/carbon composites synthesized by this easy hydrothermal route have been demonstrated to be effective molecular adsorbents for magnetic separation.

A modified two-step sol–gel route using silicon ethoxide (TEOS) has been used to synthesize amorphous sol–gel-derived silica, which has been successfully used as a cell encapsulation matrix for 3T3 mouse fibroblasts and CRL-2595 epithelial cells due to its non-toxicity. The sol–gel procedure comprised a first, low pH hydrolysis step, followed by a neutral condensation–gelation step. A high water-to-TEOS ratio and the addition of d -glucose as a porogen and source of nutrients were chosen to minimize silica dissolution and improve the biocompatibility of the process. Indeed, the cell integrity in the encapsulation process was preserved by alcohol removal from the starting solution. Cells were then added in a buffered medium, causing rapid gelation and entrapment of the cells within a randomly structured siloxane matrix in the shape of a monolith, which was maintained in the wet state. MTT and alamarBlue assays were used to check the cytotoxicity of the silica gels and the viability of entrapped cells at initial times in contact with silica. To improve cell attachment, cell clumping experiments – where groups of cells were formed – were designed, rendering improved viability. The obtained materials are therefore excellent candidates for designing tissue-culture scaffolds and implantable bioreactors for biomedical applications.

It is of great interest the design of materials able to adjust the drug amount to the clinical needs, in such a way that the dosage can be controlled as adsorption and release are modulated. The organic modification of the surface of silica-based ordered mesoporous materials has been found as key factor to effectively control the drug dosage. A range of amine-functionalization degrees led to diverse adsorption rates of sodium alendronate, and to different drug release. Taking into account that ordered mesoporous materials have shown to be ceramics with potential bone regeneration applications, these systems could be starting materials for the further design of scaffolds for bone tissue engineering with the added value of releasing sodium alendronate, a drug used for the treatment of osteoporosis.

Designed porous architecture scaffolds have been prepared with an innovative combination of techniques, avoiding the sintering stage for tissue engineering application. Firstly, hydroxyapatite/β-tricalcium phosphate HA/β-TCP/agarose porous scaffolds have been manufactured using a homogeneous ceramic/agarose suspension at low temperature, leading to non designed architecture scaffolds. In order to achieve scaffolds for bone tissue engineering applications a polymeric negative, obtained by stereolithography technique, is filled with this suspension. Afterwards, the polymeric negative is eliminated by alkaline dissolution at room temperature in order to obtain the designed architecture scaffolds. Secondly, room temperature and freeze-drying techniques have been applied in scaffolds drying stage. In this way, strong dried scaffolds, fully interconnected with high porosity, thoroughly open pores and tailored pore size have been obtained. Besides, depending on the drying technique employed, different porosity (59–80%), distribution of pores size (∼0.2 and 70 μm) and interconnected three-dimensional ellipsoidal channels between 300 μm × 380 μm and 340 μm × 460 μm can be achieved. In contact with body fluids, these scaffolds show flexibility and capacity to exert pressure into the bone defect of the patient and be easily handled by the surgeon.