Queen Volatiles as a Modulator of <Emphasis Type="BoldItalic">Tetragonisca angustula</Emphasis> Drone Behavior

Tetragonisca angustula mating occurs during the virgin queen nuptial flight, usually in the presence of a drone congregation area (DCA). The presence of virgin queen pheromone is considered the trigger for DCA establishment, although this has not been demonstrated experimentally. We established meliponaries, in different habitats, with T. angustula virgin queens during the main drone reproduction period. Eight DCAs were observed in urban areas, and all established outside or near colonies containing at least one virgin queen. The accumulation of drones in the DCAs occurred from 08:00 to 18:00 h and over 3–35 days. The number of drones in DCAs ranged from 60 to 2,000. In field trials, drones were attracted to virgin queens and also, unexpectedly, to physogastric queens. Volatiles collected from both virgin and physogastric queens elicited strong electoantennogram (EAG) responses from drones. Virgin and physogastric queen volatiles were qualitatively similar, but quantitatively different, in chemical composition. The queen’s abdomen was the principal source of these compounds. Isopropyl hexanoate (IPH), the most abundant compound in virgin queen volatiles and one of the most abundant in physogastric queen volatiles, was identified as one of the compounds that elicited EAG responses and was demonstrated to attract drones in a field test.     

Lectins of Lablab purpureus seeds

A column of chitin was utilized to separate four lectins (hemagglutinating activity) from the seeds of (Lablab purpureus L) Sweet. Two of these activities, which were bound by chitin and were also strongly inhibited by N-aeetyl-D -glucosamine, were differentiated according to their ionic properties: one is a basic (C2-S1) and the other is an acidic (C2-S2) lectin. A third N-acetyl-D -glucosamine binding lectin (Cl-2) is also acidic in nature but showed a lower binding capacity towards this sugar than C2-S2. A fourth lectin (C1-1S2) was strongly inhibited by galactose and has an acidic character. The lectin is formed by subunits of 39000 and 44000 kDa.     

Central international visibility of Brazilian psychiatric publications from 1981 to 1995

In this study, we examine the scientific output of Brazilian psychiatry, based on the databaseof the Institute for Scientific Information (ISI), publications in the 10 most important psychiatricjournals, and publications in major Brazilian journals. The number of Brazilian publications (i.e.,those carrying at least one Brazilian address) in psychiatry in the ISI database increased by 168%during the 15-year period under study (1981-1995) . Despite this growth, the relative contributionof publications in psychiatry to the country's publications in medical sciences did not change overthe 15-year period. This fraction, around 2%, remained at less than one-third of the averagecontribution of psychiatry journals to publications in medicine worldwide. The impact inferredfrom number of citations (1981-1992) shows that Brazilian articles in psychiatry were cited lessthan the world average in this field. In the 10 psychiatry journals with the highest impact,Brazilian authors published only 48 articles in the 1981-1995 period, representing only 0.2% ofthe articles in those journals. Like their American and British counterparts, Brazilian psychiatristsalso published primarily in domestic journals: 87.1% of the publications by Brazilians appeared inthe two major Brazilian psychiatric journals, compared with only 12.9% in foreign journals.Among publications in psychiatry in the ISI database, the number of articles co-authored byBrazilians with scientists from other countries increased 12.3 fold from 1981-1985 to 1991-1995,representing at the end 50% of all publications by Brazilian psychiatrists in international journals.Despite all cuts in funding for Brazilian science during the last decades, all of the articles in oursample originated in public universities, and only 10 universities were responsible for 70% of thepublications by Brazilian psychiatrists in our survey period. We conclude that Brazilianpsychiatric research is a subject worthy of particular concern, especially if we take into accountthe country's modest scientific performance and the socio-economic consequences of mentaldisorders in the Brazilian population.     

Flexible fluorescent films based on quantum dots (QDs) and natural rubber

This article presents the fabrication and characterization of polyisoprene fluorescent films doped with CdTe quantum dots (QDs). The biopolymer (polyisoprene) is extracted from natural rubber latex, generating flexible and transparent films in visible range (transmittance over 90%) ideal as a matrix to support QDs. The water solubility of the biopolymer facilitates its doping with water dispersed QDs at room temperature to obtain the fluorescent films. Thermogravimetric analysis reveals that QDs have no significant effect on the thermal properties of the biopolymer. Photophysical characterization of the solution and solid state (films) of the QDs evidenced that the polymer matrix does not influence its emission properties, the maximum fluorescence peaks have only 2 nm of difference between the solution and solid state (films) samples. Therefore, polyisoprene from natural rubber can be considered as an excellent flexible matrix to fabricate fluorescent films with QDs. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45459.     

Optimal transient performance under output set‐point reset

The purpose of this paper is to propose a new method for the optimization of the output transition in the case of set‐point reset for LTI, non‐minimum phase, possibly non‐hyperbolic plants. Assuming that the plant is stabilized by a proper feedback controller, the problem consists in finding a feedforward linear filter yielding a suitable reference trajectory for the closed‐loop system. The approach situates in the framework of model pseudo‐inversion because the external reference trajectory is computed starting from some desired features of the transient output between the two set points. A significant aspect of the new method is that the transition trajectory is not ‘ad hoc’ exactly prespecified by the designer. Rather, it is implicitly defined by the procedure for the minimization of a suitable multi‐objective quadratic cost functional. As no pre‐actuation is required, the method can be practically implemented on line and also works for the critical class of non‐hyperbolic systems. Copyright © 2015 John Wiley & Sons, Ltd.     

Coevolution of variability models and related software artifacts

Variant-rich software systems offer a large degree of customization, allowing users to configure the target system according to their preferences and needs. Facing high degrees of variability, these systems often employ variability models to explicitly capture user-configurable features (e.g., systems options) and the constraints they impose. The explicit representation of features allows them to be referenced in different variation points across different artifacts, enabling the latter to vary according to specific feature selections. In such settings, the evolution of variability models interplays with the evolution of related artifacts, requiring the two to evolve together, or coevolve. Interestingly, little is known about how such coevolution occurs in real-world systems, as existing research has focused mostly on variability evolution as it happens in variability models only. Furthermore, existing techniques supporting variability evolution are usually validated with randomly-generated variability models or evolution scenarios that do not stem from practice. As the community lacks a deep understanding of how variability evolution occurs in real-world systems and how it relates to the evolution of different kinds of software artifacts, it is not surprising that industry reports existing tools and solutions ineffective, as they do not handle the complexity found in practice. Attempting to mitigate this overall lack of knowledge and to support tool builders with insights on how variability models coevolve with other artifact types, we study a large and complex real-world variant-rich software system: the Linux kernel. Specifically, we extract variability-coevolution patterns capturing changes in the variability model of the Linux kernel with subsequent changes in Makefiles and C source code. From the analysis of the patterns, we report on findings concerning evolution principles found in the kernel, and we reveal deficiencies in existing tools and theory when handling changes captured by our patterns.     

Evaluating scenario-based SPL requirements approaches: the case for modularity,stability and expressiveness

Software product lines (SPL) provide support for productivity gains through systematic reuse. Among the various quality attributes supporting these goals, modularity, stability and expressiveness of feature specifications, their composition and configuration knowledge emerge as strategic values in modern software development paradigms. This paper presents a metric-based evaluation aiming at assessing how well the chosen qualities are supported by scenario-based SPL requirements approaches. The selected approaches for this study span from type of notation (textual or graphical based), style to support variability (annotation or composition based), and specification expressiveness. They are compared using the metrics developed in a set of releases from an exemplar case study. Our major findings indicate that composition-based approaches have greater potential to support modularity and stability, and that quantification mechanisms simplify and increase expressiveness of configuration knowledge and composition specifications.     

An economic production quantity model with random defective rate,rework process and backorders for a single stage production system

This paper revisits the economic production quantity (EPQ) model with rework process at a single-stage manufacturing system with planned backorders. It is well known that any imperfect production system of real life has random defective rates. In this direction, this paper extends an inventory model to allow random defective rates. Basically, three different inventory models are developed for three different distribution density functions such as uniform, triangular, and beta. The analytical derivation provides closed-form solution for each inventory model. We have made comparison tables of optimal results among the distribution functions. Some numerical examples and sensitivity analysis are given to illustrate the inventory models.     

Modelling of circulating fluidized bed combustion of a char

The combustion of a char in the 41 mm ID riser of a laboratory circulating fluidized bed combustor has been investigated at different air excesses and rates of solids (char and sand) circulating in the loop. Riser performance was characterized by an axial oxygen concentration profile as well as by the overall carbon content and particle size distribution. The proposed model accounts for carbon surface reaction, intraparticle and external diffusion, and attrition. External diffusion effects were relevant in the riser dense region where char was potentially entrapped in large clusters of inert solids. Experimental data and results of the model calculations are in satisfactory agreement.