Effects of <Emphasis Type="Italic">p</Emphasis>-Vinylphenyl Glycosides and Other Related Compounds on the Oviposition Behavior of <Emphasis Type="Italic">Ceratitis capitata</Emphasis>

Elaphoside-A [p-vinylphenyl (beta-D: -glucopyranosyl)-(1-->3)-beta-D: -allopyranoside], a Mediterranean fruit fly oviposition deterrent, was previously isolated from an Argentine collection of the fern Elaphoglossum piloselloides. In order to establish the structural requirements for the observed oviposition inhibition, we synthesized and characterized 4 known and 21 new aromatic glycosides structurally related to elaphoside-A. Their effects on the oviposition behavior of Ceratitis capitata females are discussed.     

Catalysts based on supported 12-molybdophosphoric acid

Catalysts preparation by equilibrium adsorption of 12-molybdophosphoric acid in water–ethanol solutions onto silica, titania, carbon and alumina is studied. The solute/support interaction follows the decreasing order: alumina, carbon, silica and titania. It is observed that the molybdophosphoric acid keeps its Keggin-type structure after being supported at room temperature on all supports. This species is stable up to 500°C on silica, 400°C on titania or carbon and 250°C for alumina. The acidity of the supported heteropoly acid decreases in the following order: silica>titania>carbon>alumina. This revised version was published online in July 2006 with corrections to the Cover Date.     

Polyurethane-ductilized epoxy resins

Amine-cured epoxy resins were modified to improve their impact properties. Urethane prepolymers (PUs), in which terminal isocyanate groups were blocked with nonylphenol (NP) for easy handling, were used as modifiers. The synthesis of the elastomers were carried out at different NCO : OH ratios: 1 : 1, 2 : 1, and 3 : 1 (PU1, PU2, and PU3). Characterization of these materials by GPC and FTIR indicated that PU1 has a negligible amount of NCO-terminated chains and no unreacted toluenediisocyanate (TDI). PU2 and PU3 have free-blocked TDI in the mixture, even after distillation under a vacuum. The molecular weight and polydispersity of the prepolymer increases as PU3 < PU2 < PU1. Copolymerization was carried out by crosslinking with a mixture of cycloaliphatic amines, which react with the epoxy ring and with the NCO groups by deblocking and urea formation. Dynamic mechanical tests were used to measure the glass transition temperatures (T_g) of the copolymers. Two T_g were found if PU1 was the epoxy modifier, indicating that phase separation took place. This was correlated with a structure of PU1 of linear chains with a negligible amount of reactive groups. Flexural and compression properties showed negligible changes for PU2- and PU3-modified epoxy, but the critical strain energy release rate (G_1C) was improved if PU2 was the modifier. This behavior was explained by the linkage of elastomeric chains into the epoxy network. The PU1–epoxy copolymer showed a completely different behavior, with the bending modulus (E_b) reduced to almost one-half with respect to that of the epoxy matrix and with largely improved impact properties. This difference was attributed to the separation of an elastomeric phase, which favors the formation of shear bands in the epoxy matrix. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68: 1781–1789, 1998     

Epoxy-based divinyl ester resin/styrene copolymers: Composition dependence of the mechanical and thermal properties

Epoxy-based divinyl ester resins (DVER) were obtained by reacting diglycidyl ether of bisphenol A (DGEBA) with methacrylic acid (MA) and characterized by FTIR and ¹H-NMR spectroscopies and gel permeation chromatography (GPC). The densities and viscosities of the DVER in styrene (S) solutions were measured at different temperatures, 25, 40, and 60°C and compositions, 3.4 to 100% by weight of styrene. Dynamic mechanical measurements (DMA) and differential scanning calorimetry (DSC) were used to determine the glass transition temperatures of the homopolymers and the DVER/S copolymers: 20, 40, 60, and 80% by weight of styrene. The values obtained are in the range limited by the homopolymers glass transition, 100°C for polystyrene and 173°C for the cured DVER. The data were well fitted if two contributions to the glass transition are taken into account: the “linear copolymer” contribution (Fox eq.) and the “crosslinking” contribution (Nielsen model). Uniaxial static compression tests were carried out to determine the modulus, yield stress, and ultimate stress in samples with different compositions. All the mentioned properties decrease with an increase in the styrene concentration in the final copolymer. It was found that the volumetric contraction during curing increases with styrene concentration. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 1059–1066, 1997     

Do low-numeracy people avoid shared decision making?

Objectives: Doctors have been increasingly encouraged to involve patients in decision making rather than pursuing the paternalistic model in which they make the decisions for their patients. But do patients want to participate in making decisions about their health? Is there a relationship between their preferences for shared decision making and numeracy skills? Are those preferences different in countries with different medical systems, and for different age groups? Extant studies cannot answer these questions because most are based on nonprobabilistic, highly selective patient samples that prevent generalizations to a broader population. Design: In a survey on probabilistic national samples in the United States and Germany, we interviewed participants with low numeracy skills (Germany: n = 127, mean numeracy = 37; United States: n = 117, mean numeracy = 36) and high numeracy skills (Germany: n = 133, mean numeracy = 96; U.S.: n = 121, mean numeracy = 91). Main Outcome Measures: Usual and preferred role in medical decision making. Results: A significant number of people with low numeracy in both the United States (35%, SE = 8.2) and Germany (30%, SE = 6.1) preferred to be more passive than they currently were. High-numeracy people, in contrast, were mostly satisfied with their current role. On average, Americans were more active than Germans. Middle-aged participants preferred to be more active compared to both younger and older ones. Conclusions: Shared decision-making preferences are related to numeracy skills, country, and age. Education efforts to increase numeracy, as well as using nonquantitative communication formats, may foster involvement of low-numeracy patients in decisions about their health. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Supercritical impregnation of drugs and supercritical fluid deposition of metals into aerogels

The presented review covers the latest research on supercritical impregnation into organic and inorganic aerogels by investigating those factors that influence the impregnation. Supercritical impregnation is a promising method for incorporating drugs within porous carriers including for water insoluble drugs. An additional step (reduction from metallic precursor to metal) is required for the supercritical impregnation of metallic precursors. Hence, this expanded method is preferably termed as supercritical fluid deposition or adsorption. Supercritical impregnation of drugs, as well as metals, are mostly influenced by interactions between the compound and aerogel matrix, supercritical impregnation conditions, and the characteristics of a compound within a supercritical fluid.     

Iron and zinc in vitro potential availability in an infant diet with fortified bread with different iron sources or with the addition of different iron absorption promoters

Home-made diets are the most frequently used complementary foods. In the present work we evaluated iron and zinc availability in a usually consumed infant diet containing either iron-fortified bread with different iron sources: ferrous sulfate, ferrous bisglycinate, NaFeEDTA. We also used non-fortified bread with absorption promoters: ascorbic acid, sodium citrate, Na2EDTA, combined with different beverages. The diet (potato, pumpkin, grits, bread, and apple) was combined with water, milk, tea, a soft drink and an orange-based artificial drink. Mineral dialyzability (D) as an indicator of potential availability was determined using an in vitro method. Statistical analysis was performed by ANOVA, and a posteriori Tukey test. There were no significant differences in FeD between diets with ferrous sulfate or ferrous bisglycinate fortified bread; in NaFeEDTA fortified bread it increased significantly (p<0.05). Iron D increase was greater in diets with bread containing absorption promoters than in those with fortified bread. The orange-based artificial drink increased FeD, while tea and milk decreased it significantly (p < 0.05). Zinc D increased significantly when the bread was fortified either with ferrous sulfate or NaFeEDTA, but remained unchanged in diets with ferrous bisglycinate fortified bread. The addition of tea or milk decreased ZnD while the orange-based artificial drink increased it significantly (p < 0.05). Regarding absorption promoters, the greater values both in FeD and ZnD were observed in diets with iron nonfortified bread containing Na2EDTA.     

Toughening of wood particle composites—Effects of sisal fibers

Sisal fibers were added to wood particle composites to enhance their toughness. The selected matrix was a commercial styrene diluted unsaturated polyester thermoset resin. Fracture tests were carried out using single‐edge notched beam geometries. Stiffness, strength, critical stress intensity factor K_IQ, and work of fracture W_f of notched specimens were determined. The incorporation of sisal fibers into wood particle composites significantly changed the fracture mode of the resulting hybrid composite. For the neat matrix and the wood particle composites, once the maximum load was reached, the crack propagated in a catastrophic way. For hybrid composites, fiber bridging and pull‐out were the mechanisms causing increased crack growth resistance. Addition of a 7% wt of sisal fibers almost doubled the K_IQ value of a composite containing 12% wt of woodflour. Moreover, the W_f increased almost 10‐fold, for the same sample. In general, the two composite toughness parameters K_IQ and W_f increased when the fraction of sisal fibers was increased. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 1982–1987, 2006     

Thermal and dynamic mechanical characterization of polypropylene‐woodflour composites

The performance of wood particle/polypropylene (PP) composites with modified compatibilities was compared. Woodflour modification was performed by esterification with maleic anhydride (MAN) and a non‐commercial maleic anhydride‐polypropylene copolymer (PPMAN) was selected as compatibilizing agent. The thermogravimetric analysis indicates that the onset of thermal degradation of treated woodflour occurs at lower temperature than that of the untreated one, and the same behavior was found in the corresponding composites. Differential scanning calorimetry indicated that both woodflours acted as nucleating agents for PP, while only treated woodflour induced PP crystallization in β‐phase in the composites. X‐ray diffractometry demonstrated that the crystallization in β‐phase was a shear‐induced phenomenon favored by the chemical modification of the woodflour surface. Dynamic mechanical studies suggested that composite properties decreased at concentrations higher than 40 wt% of woodflour and that the overall performance of MAN‐treated woodflour composites was lower than that of the composites where a compatibilizing agent was added.     

Characterization of chitosan/caseinate films

Films made from sodium caseinate and/or chitosan, using glycerol as plasticizer, were prepared by casting from aqueous solutions. Films cryo‐fractured surfaces were examined by SEM. FTIR spectra of the chitosan/caseinate films showed an increase in the intensity of the amide band, corresponding to the strong interactions developed by the polyelectrolytic complexation of both components. Addition of 28 wt% of glycerol to caseinate films, conditioned at 50% relative humidity (RH), reduced the modulus from 2908 to 250.9 MPa, while the ultimate elongation increased from 4 to 63.2%. Increment to 80% RH further reduced the modulus down to 52.8 MPa. Similar results were found for the glycerol plasticization of chitosan films. The complex films showed a moderate improvement of the tensile strength (19.6 MPa) and an increase of the impact strength (35.6 GPa) with respect to those corresponding of chitosan films (17 MPa and 26.6 GPa, respectively). These properties were markedly improved with respect to those of caseinate (6.2 MPa and 13.4 GPa, respectively). The interactions developed between the cationic polymer chitosan, and the Na‐caseinate carboxyl groups, lead to polyelectrolyte complexation in forming the film, which is proposed as the reason for improvement with respect to caseinate or chitosan films. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008