Resolving scientific disputes by the joint design of crucial experiments by the antagonists: Application to the Erez–Latham dispute regarding participation in goal setting.

In this monograph we describe a unique method for resolving scientific disputes: the joint design of crucial experiments by the antagonists themselves with the help of a mediator. This method was applied to the issue of the effect of participation on goal commitment and performance. In research on this topic, Latham and his colleagues had obtained markedly different results from those obtained by Erez and her colleagues. With Locke serving as a third party mediator, Latham and Erez designed four experiments to resolve the discrepancies. The experiments were conducted at the University of Washington and the University of Maryland. The results revealed that the major reason for the difference was that Erez gave very brief tell instructions to her assigned goal subjects, whereas Latham used a tell and sell approach. Four additional factors also contributed to the earlier difference in findings: goal difficulty, setting personal goals before goal treatments were introduced, self-efficacy-inducing instructions, and instructions to reject disliked goals. It was concluded that (a) the differences between Latham and Erez can be explained on the basis of differences in specific procedures, and (b) the method used to resolve this dispute should be used by other investigators. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Calcium lactate effect on the shelf life of osmotically dehydrated guavas

The effect of calcium lactate on osmodehydrated guavas in sucrose and maltose solutions was monitored during storage under passive modified atmosphere for 24 d at 5 °C. Sample texture and color characteristics, microbial spoilage, sensory acceptance, structural changes, and gas composition inside the packages were periodically evaluated. Calcium lactate inhibited microbial growth on guavas, with yeast and mold counts in the order of 10(2) CFU/g throughout storage. The calcium salt reduced respiration rate of guava products, showing O(2) and CO(2) concentrations around 18% and 3% inside the packages. A firming effect on fruit texture, with up to 5 and 2 times higher stress and strain at failure values and tissue structure preservation could also be attributed to calcium lactate use. However, fruits treated with calcium lactate, osmodehydrated in maltose and sucrose solutions, showed sensory acceptance scores below the acceptability limit (4.5) after 13 and 17 d of storage, respectively.     

Thermo‐mechanical properties of candelilla wax and dotriacontane organogels in safflower oil

The thermo‐mechanical properties of organogels developed by a complex mixture of n‐alkanes present in candelilla wax (CW) were investigated and compared with the ones of organogels developed by a pure n‐alkane, dotriacontane (C₃₂). In both cases, the liquid phase used was safflower oil high in triolein (SFO) and the variables studied were two levels of gelator concentration (1 and 3%), cooling rates of 1 and 10 °C/min, and two gel setting temperatures, 5 and 25 °C (T_set). Based on comparisons of the organogels made with C₃₂, the presence of minor molecular components in CW had a profound effect on the crystal habit of the n‐alkanes in CW‐based organogels, and therefore on their physical properties. Thus, independent of the cooling rate and T_set, C₃₂ showed a higher solubility and higher self‐assembly capability in the SFO than CW. Nevertheless, for the same gelator concentration and time‐temperature conditions, C₃₂ organogels had lower G' profiles than CW organogels. Additionally, independent of the type of gelator, more stable organogel structures were developed at T_set = 5 °C and using the lower cooling rate. The rheological behavior of the organogels was explained considering the formation of a rotator phase by the n‐alkanes, its solid‐solid transition, and their dependence as a function of the cooling rate and T_set. The results here obtained showed that it is possible to gelate SFO through organogelation with CW and without the use of trans fats.     

Some Observations of Diatoms Under Turbulence

The effect of turbulence on several freshwater diatom taxa was investigated and our findings are described herein. We have compared diatom morphology in shallow natural systems that experience turbulence due to wind and in river/waterfall systems where turbulence is due to high flow rates. We have also introduced turbulence into diatom laboratory cultures by mechanical shaking and by forcing air into the media. In particular, we have studied diatoms in five independent environments or cultures: the freshwater diatoms Tabellaria and Eunotia in equatorial lakes experiencing extreme seasonal variability in depth; two freshwater diatom monocultures of Aulacoseira granulata var angustissima and Melosira varians in the laboratory; and a freshwater diatom community possessing equal amounts (by number) of elongated and non-elongated diatoms (mostly Nitzschia and mostly Cyclotella, respectively) in the laboratory. We have demonstrated the effect of turbulence on freshwater diatom frustule morphologies and, perhaps more importantly, the effect of turbulence on freshwater diatom species population after controlled perturbation of the organisms’ environment. It has been widely reported that symmetry is often preferred in biological evolution, however here we have observed a preference towards asymmetry for the survival of diatoms in the presence of environmental stress (in particular, turbulence). We also note that to date there have been no systematic attempts to manipulate diatom frustules using external stimuli. We therefore present a proof-of-concept study in order to demonstrate: (i) that diatom morphologies can be manipulated by controlled simple external triggers (chemical and physical) (ii) that population balance (i.e. natural selection) can be controlled via simple external triggers (chemical and physical). This approach could open up an entire new field of future studies wherein controlled environmental perturbations are used to manipulate the structure, form, growth and reproduction of biological species.     

The promise of a community-based approach to managing severe malnutrition: A case study from Ethiopia

BACKGROUND: Community-based therapeutic care (CTC) is a new strategy in the arsenal of techniques to manage complex nutritional emergencies in rural communities. The CTC approach uses a newly developed ready-to-use therapeutic food, Plumpynut, to rehabilitate severely malnourished children in their home communities. Emerging literature has suggested the CTC strategy yielded results that were superior to those of programs limited to therapeutic feeding centers, as measured by rates of coverage and numbers of children rehabilitated. OBJECTIVE: To compare the effectiveness of the CTC strategy in combination with conventional treatments for acute malnutrition. The expectation was that this program would support the growing consensus on the effectiveness of CTC strategies. METHODS: Data from monitoring the initial phase of program implementation were reviewed to ascertain program impact. The number of children participating and the outcome of their participation were assessed. RESULTS: Families became key participants in the rehabilitation of their children, and communities became strengthened through the mobilization of local networks and the improved knowledge base of local health workers. Recovery rates were comparable with international standards, and coverage far exceeded that of traditional center-based care. CONCLUSIONS: CTC is an important tool to effectively address nutritional emergencies and may be a valuable entry point for long-term development, since it fosters capacity building and improvement in local communities. CTC programs may eventually be viewed as the entry point for more sustained development-oriented interventions, thus helping make the transition from relief to development.     

Changes in the volatile composition of red wines during aging in oak barrels due to microoxygenation treatment applied before malolactic fermentation

Microoxygenation is a wine-making technique consisting in the addition of small and controlled amounts of oxygen. This study has examined the effect of this technique on the volatile composition of two red single variety wines during two successive vintages. The microoxygenation treatment was applied at the end of alcoholic fermentation and before beginning malolactic fermentation. Once the microoxygenation treatment had finished, wines were aged in new American oak barrels for 12 months. The results obtained showed that the microoxygenation treatment did not cause significant changes in the varietal and fermentation volatile compounds, however microoxygenation slowed down the extraction of some of the volatile compounds extracted from wood. A varietal and vintage effect was also observed for some of the compounds studied.     

Antioxidant potential of single-variety red wines aged in the barrel and in the bottle

Wine constitutes a dynamic system in continuous evolution, in which numerous reactions involving polymerization and condensation take place between its phenolic compounds during the ageing process, which undoubtedly affect its structure and, very probably, its antioxidant effect. This study set out to evaluate the effect of ageing on the antioxidant potential of wine. A group of 162 wines were studied, of varying ages, which had undergone different ageing processes, both in the barrel and in the bottle, and which were prepared from different grape varieties and vintages. Total antioxidant capacity (ABTS, DPPH, DMPD, ORAC and FRAP), scavenger activity (HRSA and SRSA) and the biomarkers of oxidative stress (DNA-damage and ABAP-LP) were all analysed. The assay methods showed different behaviours for the same wines, thus the young wines presented higher indices for ABTS, DPPH and DMPD, whereas those that were aged showed higher indices for ABAP-LP and ORAC. Finally, the antioxidant potential of the wines in the study appeared not to be influenced by other factors, such as microoxygenation or grape variety.     

Colloidal synthesis of Au nanoparticles using polyelectrolytes with 1,3,4-thiadiazole as reducing agents

Heterocyclic compounds are well known for their biological activity and coordination properties. Some heterocyclic compounds have been employed in the stabilization against coalescence of metallic nanoparticles in colloidal solutions, for example, tetrazole, triazole, and pyrazole. The aim of this work is to design new polyelectrolytes with heterocyclic pendant groups useful as reducing agents of Au³⁺ and as stabilizing agents for the synthesis of colloidal Au nanoparticles. Thus, polyelectrolytes with thiosemicarbazone and 1,3,4-thiadiazole pendant groups were used as reducing agents of Au³⁺ ions and stabilizing agents of Au nanoparticles. The voltammetry study of the polyelectrolytes showed that one with thiosemicarbazone pendant groups is the better reducing agent than polyelectrolytes with heterocyclic pendant groups. The polyelectrolytes can control the growth of the nanoparticles, obtaining structures with an average size of 9 nm. In this study, it was concluded that the nature of the heterocyclic group does not have an effect on the shape of nanoparticles and quasi-spherical nanoparticles were obtained with all polyelectrolytes. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47790.