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The solubility of standards of the representative biopolymers of lignocellulosic biomass (cellulose, hemicellulose, and lignin) in mixtures of controlled composition of an ionic liquid capable of dissolving biomass (namely 1-ethyl-3methylimidazolium acetate, [C 2 mim][OAc]) and a volatile antisolvent (namely ethanol) was explored. On the basis of these results, a scheme for the recovery of dissolved biomass fractions from the ionic liquid medium via controlled addition of the antisolvent was proposed. The recoverability of the ionic liquid from its mixture with ethanol was evaluated via thermogravimetrical analysis. A characterization of key physical properties of the mixtures of [C 2 mim][OAc] and ethanol (namely density, viscosity, and surface tension) was carried out both as a function of temperature and of composition.

In this intervention, participants design and implement an HIV/AIDS prevention project for Mexican homosexual men. The intervention is consistent with, and contributes to, empowerment theory because it enhances collective action, provides opportunities to develop knowledge and skills, creates needed resources, and includes shared control with professional and among participants. The intervention described provides an illustration of an empowering process and distinguishes itself from empowerment outcomes. An evaluation of the project is also described, but the outcomes were HIV/AIDS-related behaviors rather than psychological empowerment of the participants. The results suggest that the participants' HIV/AIDS knowledge and preventive behavior improved when compared to individuals who did not participate in the intervention. In addition, the intervention generated community change initiated by participants. Implications for designing interventions using an empowerment approach are discussed.

In Europe, several diseases of maize (Zea mays L.) including seedling blight and stalk rot are caused by different Fusarium species, mainly Fusarium graminearum, F. verticillioides, F. subglutinans, and F. proliferatum (3). In recent years, these Fusarium spp. have received significant attention not only because of their impact on yield and grain quality, but also for their association with mycotoxin contamination of maize kernels (1,4). From October 2011 to October 2012, surveys were conducted in a maize plantation located in Galicia (northwest Spain). In each sampling, 100 kernels and 10 maize stalks were collected from plants exhibiting symptoms of ear and stalk rot. Dried kernels and small stalk pieces (1 to 2 cm near the nodes) were placed onto potato dextrose agar medium and incubated in the dark for 7 days. Fungal colonies displaying morphological characteristics of Fusarium spp. (2) were subcultured as single conidia onto SNA (Spezieller Nahrstoffarmer agar) (2) and identified by morphological characteristics, as well as by DNA sequence analysis. A large number of Fusarium species (F. verticillioides, F. subglutinans, F. graminearum, and F. avenaceum) (1,2) were identified. These Fusarium species often cause ear and stalk rot on maize. In addition, a new species, F. temperatum, recently described in Belgium (3), was also identified. F. temperatum is within the Gibberella fujikuroi species complex and is morphologically and phylogenetically closely related to F. subglutinans (2,3). Similar to previous studies (3), our isolates were characterized based on the presence of white cottony mycelium, becoming pinkish white. Conidiophores were erect, branched, and terminating in 1 to 3 phialides. Microconidia were abundant, hyaline, 0 to 2 septa; ellipsoidal to oval, produced singly or in false heads, and on monophialides, intercalary phialides, and polyphialides. Microconidia were not produced in chains. No chlamydospores were observed (3). Macroconidia in carnation leaf agar medium (2) were hyaline, 3 to 6 septate, mostly 4, falcate, with a distinct foot-like basal cell (2,3). DNA was amplified with primers ITS1/ITS4 and EF1/EF2 (3). Partial sequences of gene EF-1α showed 100% homology with F. temperatum (3) (GenBank Accession Nos. HM067687 and HM067688). DNA sequences of EF-1α gene and ITS region obtained were deposited in GenBank (KC179824, KC179825, KC179826, and KC179827). Pathogenicity of one representative isolate was confirmed using a soil inoculation method adapted from Scauflaire et al., 2012 (4). F. temperatum isolate was cultured on sterile wheat grains. Colonized wheat grains (10 g) were mixed with sterilized sand in 10 cm diameter pots. Ten kernels per pot were surface disinfected in 2% sodium hypochlorite for 10 min, rinsed with sterilized water, drained (4), placed on the soil surface, and covered with a 2 cm layer of sterilized sand. Five pots were inoculated and five uninoculated controls were included. Pots were maintained at 22 to 24°C and 80% humidity for 30 days. Seedling malformations, chlorosis, shoot reduction, and stalk rot were observed on maize growing in inoculated soil and not from controls. F. temperatum was reisolated from the inoculated seedlings but not from the controls. References: (1) B. J. Bush et al. Phytopathology 94:88, 2003. (2) J. F. Leslie et al. The Fusarium Laboratory Manual, page 388. Blackwell Publishing, 2006. (3) J. Scauflaire et al. Mycologia 103:586, 2011. (4) J. Scauflaire et al. Eur. J. Plant Pathol. 133:911, 2012.

Ionic liquids are the basis of a promising technology for the dissolution and fractionation of lignocellulosic materials. The use of a miscible organic cosolvent as additive may improve the physical properties of the dissolving fluid, as compared to those of the ionic liquid alone. Alternatively, this organic substance added in larger amounts can act as antisolvent for the regeneration of the nonvolatile lignocellulose fractions dissolved. In this work, mixtures of methanol and 1-ethyl-3methylimidazolium acetate (an archetypal ionic liquid for dissolution of lignocelluloses) were characterized from a thermal and physical point of view. Their ability to dissolve representative standards of the lignocellulose biopolymers (cellulose, hemicellulose, lignin) was assessed. Very different solubilities of the three biopolymer standards were observed as a function of composition of the solvent, suggesting the possibility of a selective dissolution procedure to separate mixtures of the disengaged polymers. Precipitation tests showed that fractionated recovery of the dissolved biopolymers from the ionic liquid was not possible by direct addition of moderate amounts of methanol, due to formation of gel-like phases.

A thermal and physical characterization of the binary mixtures of the ionic liquid 1-ethyl-3-methylimidazolium acetate ([C 2 mim][OAc]) with 1-propanol or with 2-propanol was carried out. Thermogravimetric analyses confirmed that the stability of the ionic liquid is not reduced by the presence of the propanols. The density, viscosity, refractive index, and surface tension of the two binary systems were experimentally determined over the entire composition range, at atmospheric pressure, and from 288.15 to 348.15 K (for the system [C 2 mim][OAc] + 1-propanol) or to 338.15 K (for the system [C 2 mim][OAc] + 2-propanol). All properties were found to decrease with an increase in temperature and in the concentration of alcohol in the system. Negative excess molar volume, positive logarithm viscosity change of mixing, and mostly negative surface tension change of mixing were obtained from the experimental data for the isotherms investigated. An analysis of the trends of these property changes of mixing in systems [C 2 mim][OAc] + alcohol was carried out. In assessing the trend for the surface tension change of mixing, experimental data for the surface tension of the system [C 2 mim][OAc] + methanol were also obtained.

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