Artigos científicos como recurso didático no ensino superior de Química

Chemistry teachers increasingly use research articles in their undergraduate courses. This trend arises from current pedagogical emphasis on active learning and scientific process. In this paper, we describe some educational experiences on the use of research articles in chemistry higher education. Additionally, we present our own conclusions on the use of such methodology applied to a scientific communication course offered to undergraduate chemistry students at the University of São Paulo, Brazil.

Formação docente no ensino superior de Química: contribuições dos programas de aperfeiçoamento de ensino

The literature on the challenges of teacher education in undergraduate chemistry teaching is limited. In the present study, the application of didactic proposals elaborated by two authors of this paper, graduate students and teaching assistants of the teaching improvement program at University of São Paulo, was investigated in terms of their contribution to the teaching assistants' education and undergraduate students' receptivity toward them. Such proposals were based on the jigsaw cooperative learning strategy and applied in two undergraduate courses. The results indicate students' good receptivity and suggest their importance to teaching assistants' education.

Non-coding RNAs in schistosomes: an unexplored world

Non-coding RNAs (ncRNAs) were recently given much higher attention due to technical advances in sequencing which expanded the characterization of transcriptomes in different organisms. ncRNAs have different lengths (22 nt to >1, 000 nt) and mechanisms of action that essentially comprise a sophisticated gene expression regulation network. Recent publication of schistosome genomes and transcriptomes has increased the description and characterization of a large number of parasite genes. Here we review the number of predicted genes and the coverage of genomic bases in face of the public ESTs dataset available, including a critical appraisal of the evidence and characterization of ncRNAs in schistosomes. We show expression data for ncRNAs in Schistosoma mansoni. We analyze three different microarray experiment datasets: (1) adult worms' large-scale expression measurements; (2) differentially expressed S. mansoni genes regulated by a human cytokine (TNF-α) in a parasite culture; and (3) a stage-specific expression of ncRNAs. All these data point to ncRNAs involved in different biological processes and physiological responses that suggest functionality of these new players in the parasite's biology. Exploring this world is a challenge for the scientists under a new molecular perspective of host-parasite interactions and parasite development.

Bioreduction of substituted a-tetralones promoted by Daucus carota root

The bioreduction of a series of substituted a-tetralones, carried out using Daucus carota root (carrot), afforded the corresponding homochiral a-tetralols in variable conversions (9 to 90%) and excellent enantiomeric excesses. Two of the assayed a-tetralones were resistant to the bioreduction conditions. The absolute configurations of four a-tetralols were assigned as being (S), by comparison to the (S)-enantiomers obtained by kinetic resolution promoted by CALB-catalysed acetylation. Additionally, the new 5-methoxy-6-methyl-1-tetralone was synthesized in seven steps from 3-methylsalicylic acid.

Description and phylogenetic analysis of the Calycopidina (Lepidoptera, Lycaenidae, Theclinae, Eumaeini): a subtribe of detritivores

Description and phylogenetic analysis of the Calycopidina (Lepidoptera, Lycaenidae, Theclinae, Eumaeini): a subtribe of detritivores. The purpose of this paper is to establish a phylogenetic basis for a new Eumaeini subtribe that includes those lycaenid genera in which detritivory has been recorded. Morphological characters were coded for 82 species of the previously proposed "Lamprospilus Section" of the Eumaeini (19 of these had coding identical to another species), and a phylogenetic analysis was performed using the 63 distinct ingroup terminal taxa and six outgroups belonging to four genera. Taxonomic results include the description in the Eumaeini of Calycopidina Duarte & Robbins new subtribe (type genus Calycopis Scudder, 1876), which contains Lamprospilus Geyer, Badecla Duarte & Robbins new genus (type species Thecla badaca Hewitson), Arzecla Duarte & Robbins new genus (type species Thecla arza Hewitson), Arumecla Robbins & Duarte, Camissecla Robbins & Duarte, Electrostrymon Clench, Rubroserrata K. Johnson & Kroenlein revalidated status, Ziegleria K. Johnson, Kisutam K. Johnson & Kroenlein revalidated status, and Calycopis. Previous "infratribe" names Angulopina K. Johnson & Kroenlein, 1993, and Calycopina K. Johnson & Kroenlein, 1993, are nomenclaturally unavailable and polyphyletic as proposed. New combinations include Badecla badaca (Hewitson), Badecla picentia (Hewitson), Badecla quadramacula (Austin & K. Johnson), Badecla lanckena (Schaus), Badecla argentinensis (K. Johnson & Kroenlein), Badecla clarissa (Draudt), Arzecla arza (Hewitson), Arzecla tarpa (Godman & Salvin), Arzecla canacha (Hewitson), Arzecla calatia (Hewitson), Arzecla tucumanensis (K. Johnson & Kroenlein), Arzecla sethon (Godman & Salvin), Arzecla nubilum (H. H. Druce), Arzecla paralus (Godman & Salvin), Arzecla taminella (Schaus), Arzecla albolineata (Lathy), Electrostrymon denarius (Butler & H.Druce), Electrostrymon guzanta (Schaus), Electrostrymon perisus (H. H. Druce), Rubroserrata mathewi (Hewitson), Rubroserrata ecbatana (Hewitson), Kisutam micandriana (K. Johnson), and Kisutam syllis (Godman & Salvin). The structure of the male genitalia lateral window, labides, and brush organs are described and discussed, as are the female genitalia signa of the corpus bursae and 8th abdominal tergum. Widespread wing pattern sexual dimorphism in the Calycopidina is noted and illustrated, and the presence of alternating dark and light bands on the ventral wings of both sexes is discussed. The evidence for detritivory in Lamprospilus, Badecla, Arzecla, Arumecla, Camissecla, Electrostrymon, Ziegleria, Kisutam, and Calycopis is summarized using the new classification.

Synchronization of Discrete-Time Chaotic Systems in Bandlimited Channels

Over the last couple of decades, many methods for synchronizing chaotic systems have been proposed with communications applications in view. Yet their performance has proved disappointing in face of the nonideal character of usual channels linking transmitter and receiver, that is, due to both noise and signal propagation distortion. Here we consider a discrete-time master-slave system that synchronizes despite channel bandwidth limitations and an allied communication system. Synchronization is achieved introducing a digital filter that limits the spectral content of the feedback loop responsible for producing the transmitted signal. Copyright (C) 2009 Marcio Eisencraft et al.

Laser Phototherapy for Stevens-Johnson Syndrome: A Case Report

Background and Objective: Stevens-Johnson syndrome (SJS) is a life-threatening dermatosis characterized by epidermal sloughing and stomatitis. We report the case of a 7-year-old boy in whom laser phototherapy (LPT) was highly effective in reversing the effects of an initial episode of SJS that had apparently developed in association with treatment with phenobarbital for a seizure disorder. The patient was first seen in the intensive care unit (ICU) of our institution with fever, cutaneous lesions on his extremities, trunk, face, and neck; mucosal involvement of his genitalia and eyes (conjunctivitis); ulcerative intraoral lesions; and swollen, crusted, and bleeding lips. He reported severe pain at the sites of his intraoral and skin lesions and was unable to eat, speak, swallow, or open his mouth. Materials and Methods: Trying to prevent and minimize secondary infections, gastric problems, pain, and other complications, the patient was given clindamycin, ranitidine, dipyrone, diphenhydramine (Benadryl) drops, and morphine. In addition, he was instructed to use bicarbonate solution and Ketoconazole (Xylogel) in the oral cavity. Because of the lack of progress of the patient, the LPT was selected. Results: At 5 days after the initial session of LPT, the patient was able to eat gelatin, and on the following day, the number and severity of his intraoral lesions and his labial crusting and swelling had diminished. By 6 days after his initial session of LPT, most of the patient's intraoral lesions had disappeared, and the few that remained were painless; the patient was able to eat solid food by himself and was removed from the ICU. Ten sessions of LPT were conducted in the hospital. The patient underwent three further and consecutive sessions at the School of Dentistry, when complete healing of his oral lesions was observed. Conclusion: The outcome in this case suggests that LPT may be a new adjuvant modality for SJS complications.

Restricted-Range Fishes and the Conservation of Brazilian Freshwaters

Background: Freshwaters are the most threatened ecosystems on earth. Although recent assessments provide data on global priority regions for freshwater conservation, local scale priorities remain unknown. Refining the scale of global biodiversity assessments (both at terrestrial and freshwater realms) and translating these into conservation priorities on the ground remains a major challenge to biodiversity science, and depends directly on species occurrence data of high taxonomic and geographic resolution. Brazil harbors the richest freshwater ichthyofauna in the world, but knowledge on endemic areas and conservation in Brazilian rivers is still scarce. Methodology/Principal Findings: Using data on environmental threats and revised species distribution data we detect and delineate 540 small watershed areas harboring 819 restricted-range fishes in Brazil. Many of these areas are already highly threatened, as 159 (29%) watersheds have lost more than 70% of their original vegetation cover, and only 141 (26%) show significant overlap with formally protected areas or indigenous lands. We detected 220 (40%) critical watersheds overlapping hydroelectric dams or showing both poor formal protection and widespread habitat loss; these sites harbor 344 endemic fish species that may face extinction if no conservation action is in place in the near future. Conclusions/Significance: We provide the first analysis of site-scale conservation priorities in the richest freshwater ecosystems of the globe. Our results corroborate the hypothesis that freshwater biodiversity has been neglected in former conservation assessments. The study provides a simple and straightforward method for detecting freshwater priority areas based on endemism and threat, and represents a starting point for integrating freshwater and terrestrial conservation in representative and biogeographically consistent site-scale conservation strategies, that may be scaled-up following naturally linked drainage systems. Proper management (e. g. forestry code enforcement, landscape planning) and conservation (e. g. formal protection) of the 540 watersheds detected herein will be decisive in avoiding species extinction in the richest aquatic ecosystems on the planet.

Increasing the symmetry of drug crystals: a monoclinic conformational polymorph of the platelet antiaggregating agent ticlopidine hydrochloride

Ticlopidine hydrochloride (TICLID (R)) is a platelet antiaggregating agent whose use as a potent antithrombotic pharmaceutical ingredient is widespread, even though this drug has not been well characterized in the solid state. Only the crystal phase used for drug product manufacturing is known. Here, a new polymorph of ticlopidine hydrochloride was discovered and its structure was determined. While the antecedent polymorph crystallizes in the triclinic space group P (1) over bar, the new crystal phase was solved in the monoclinic space group P2(1)/c. Both polymorphs crystallize as racemic mixtures of enantiomeric (ticlopidine)(+) cations. Detailed geometrical and packing comparisons between the crystal structures of the two polymorphs have allowed us to understand how different supramolecular architectures are assembled. It was feasible to conclude that the main difference between the two polymorphs is a rotation of about 120 degrees on the bridging bond between the thienopyridine and o-chlorobenzyl moieties. The differential o-chlorobenzyl conformation is related to changeable patterns of weak intermolecular contacts involving this moiety, such as edge-to-face Cl center dot center dot center dot pi and C-H center dot center dot center dot pi interactions in the new polymorph and face-to-face pi center dot center dot center dot pi contacts in the triclinic crystal phase, leading to a symmetry increase in the ticlopidine hydrochloride solid state form described for the first time in this study. Other conformational features are slightly different between the two polymorphs, such as the thienopyridine puckerings and the o-chlorophenyl orientations. These conformational characteristics were also correlated to the crystal packing patterns.

Inference of gene regulatory networks from time series by Tsallis entropy

Background: The inference of gene regulatory networks (GRNs) from large-scale expression profiles is one of the most challenging problems of Systems Biology nowadays. Many techniques and models have been proposed for this task. However, it is not generally possible to recover the original topology with great accuracy, mainly due to the short time series data in face of the high complexity of the networks and the intrinsic noise of the expression measurements. In order to improve the accuracy of GRNs inference methods based on entropy (mutual information), a new criterion function is here proposed. Results: In this paper we introduce the use of generalized entropy proposed by Tsallis, for the inference of GRNs from time series expression profiles. The inference process is based on a feature selection approach and the conditional entropy is applied as criterion function. In order to assess the proposed methodology, the algorithm is applied to recover the network topology from temporal expressions generated by an artificial gene network (AGN) model as well as from the DREAM challenge. The adopted AGN is based on theoretical models of complex networks and its gene transference function is obtained from random drawing on the set of possible Boolean functions, thus creating its dynamics. On the other hand, DREAM time series data presents variation of network size and its topologies are based on real networks. The dynamics are generated by continuous differential equations with noise and perturbation. By adopting both data sources, it is possible to estimate the average quality of the inference with respect to different network topologies, transfer functions and network sizes. Conclusions: A remarkable improvement of accuracy was observed in the experimental results by reducing the number of false connections in the inferred topology by the non-Shannon entropy. The obtained best free parameter of the Tsallis entropy was on average in the range 2.5 <= q <= 3.5 (hence, subextensive entropy), which opens new perspectives for GRNs inference methods based on information theory and for investigation of the nonextensivity of such networks. The inference algorithm and criterion function proposed here were implemented and included in the DimReduction software, which is freely available at http://sourceforge.net/projects/dimreduction and http://code.google.com/p/dimreduction/.

Influence of physical and geometrical parameters on three-dimensional load transfer mechanism at tunnel face

Three-dimensional discretizations used in numerical analyses of tunnel construction normally include excavation step lengths much shorter than tunnel cross-section dimensions. Simulations have usually worked around this problem by using excavation steps that are much larger than the actual physical steps used in a real tunnel excavation. In contrast, the analyses performed in this study were based on finely discretized meshes capable of reproducing the excavation lengths actually used in tunnels, and the results obtained for internal forces are up to 100% greater than those found in other analyses available in the literature. Whereas most reports conclude that internal forces depend on support delay length alone, this study shows that geometric path dependency (reflected by excavation round length) is very strong, even considering linear elasticity. Moreover, many other solutions found in the literature have also neglected the importance of the relative stiffness between the ground mass and support structure, probably owing to the relatively coarse meshes used in these studies. The analyses presented here show that relative stiffness may account for internal force discrepancies in the order of 60%. A dimensionless expression that takes all these parameters into account is presented as a good approximation for the load transfer mechanism at the tunnel face.

The solution structure of the N-terminal zinc finger of GATA-1 reveals a specific binding face for the transcriptional co-factor FOG

Zinc fingers (ZnFs) are generally regarded as DNA-binding motifs. However, a number of recent reports have implicated particular ZnFs in the mediation of protein-protein interactions. The N-terminal ZnF of GATA-1 (NF) is one such finger, having been shown to interact with a number of other proteins, including the recently discovered transcriptional co-factor FOG. Here we solve the three-dimensional structure of the NF in solution using multidimensional H-1/N-15 NMR spectroscopy, and we use H-1/N-15 spin relation measurements to investigate its backbone dynamics. The structure consists of two distorted beta-hairpins and a single alpha-helix, and is similar to that of the C-terminal ZnF of chicken GATA-1. Comparisons of the NF structure with those of other C-4-type zinc binding motifs, including hormone receptor and LIM domains, also reveal substantial structural homology. Finally, we use the structure to map the spatial locations of NF residues shown by mutagenesis to be essential for FOG binding, and demonstrate that these residues all lie on a single face of the NE Notably, this face is well removed from the putative DNA-binding face of the NE an observation which is suggestive of simultaneous roles for the NF; that is, stabilisation of GATA-1 DNA complexes and recruitment of FOG to GATA-1-controlled promoter regions.

Dysmorphogenesis in psychosis: Quantitative and qualitative measures involving the head and face

In this study, we examined qualitative and quantitative measures involving the head and face in a sample of patients and well controls drawn from the Brisbane Psychosis Study. Patients with psychosis (n=310) and age and sex-matched controls (n=303) were drawn from a defined catchment area. Features assessed involved hair whorls (position, number, and direction), eyes (epicanthus), supraorbital ridge, ears (low set, protrusion, hypoplasia, ear lobe attachment, asymmetry, helix width), and mouth (palate height and shape, palate ridges, furrowed and bifid tongue). Quantitative measures related to skull size (circumference, width and length) selected facial heights and depths. The impact of selected risk factors (place and season of birth, fathers' occupation at time of birth, selfreported pregnancy and birth complications, family history) were examined in the entire group, while the association between age of onset and dysmorphology was assessed within the patient group. Significant group (cases versus controls) differences included: patients had smaller skull bases, smaller facial heights, larger facial depths, lower set and protruding ears, different palate shape and fewer palate ridges. In the entire sample significant associations included: (a) those with positive family history of mental illness bad smaller head circumference, cranial length and facial heights; (b) pregnancy and birth complications was associated with smaller facial beights: (c) larger head circumference was associated with higher ranked fathers' occupations at birth. Within the patient group, age of onset was significantly lower in those with more qualitative anomalies or with larger facial heights. The group differences were not due to outliers or distinct subgroups, suggesting that the factors responsible for the differences may be subtle and widely dispersed in the patient group. The Stanley Foundation supported this project.

Management Innovation at the Brazilian Superior Tribunal of Justice

We describe administrative reform involving management innovation undertaken at the Superior Tribunal of Justice, Brazil`s highest appellate court for infra-constitutional cases. The innovation is the introduction of a new management model based on strategic planning and a process management approach to work processes. Introduction of the new model has been supported by the use of information technology and project management techniques. Qualitative methods were used for data collection and analysis. Findings reveal that the innovation is contributing to the development of a systemic overview of key processes, reducing the fragmenting effects of the division of work activities within the Tribunal. At least three new organizational routines or capabilities have been developed as a result of the innovation studied: Electronic Court Management, Project Management, and Process Management. The paper contributes to knowledge about court management, a field that has received little research attention in the public administration literature.