The small species of Belostoma Latreille (Heteroptera, Belostomatidae). III. A revision of oxyurum group, with a new species from Brazil and description of the male of B. noualhieri Montandon

Species of the oxyurum group (sensu Lauck) consist of five extant Neotropical small species, whose lengths range 15.0 to 20.0 mm. The anterior interocular width about 1.5 times the width of an eye and ventral diverticulum of phallus flattened, circular, and large are, in combination, diagnostic. The small species of the oxyurum group were included in the Lauck´s key to the identification of the species groups, without dealing with the species included in it because many of them are very similar in appearance. Therefore here we redescribe and key the Belostoma species of the oxyurum group. Belostoma oxyurum (Dufour) is newly recorded from Brazil (Paraná and Rio Grande do Sul). Holotype and lectotype are designated for B. oxyurum and B. sanctulum Montandon, respectively. The aspect of the prosternal keel, the ratio between the width of the ventral diverticulum of phallus and its length in ventral view, and the aspect of dorsal arms of ventral diverticulum have proven useful for better species delimitation. Based on specimens from Pará State (N. Brazil), Belostoma carajaensis Ribeiro & Estévez, sp. nov. is described and illustrated. This new species differs from B. sanctulum in having anteoculus shorter than interoculus and the dorsal arms of ventral diverticulum divergent and large. A male specimen of B. noualhieri Montandon was collected in São Paulo State and based mainly on features of male genitalia, this species is here also included under oxyurum group.

Veliidae (Insecta, Heteroptera, Gerromorpha) from southeastern Brazil: three new species from Rio de Janeiro State, a new species group for Neotropical Rhagovelia Mayr, and notes on distribution and synonymy

Microvelia nelsoni sp. nov., M. takiyae sp. nov., and Rhagovelia mangaratiba sp. nov. are described. Rhagovelia scitula and R. whitei are transferred from the robusta group to the new whitei group. Rhagovelia denticulata is synonymized under R. scitula. Microvelia longipes, Oiovelia brasiliensis, Rhagovelia sooretama, R. trianguloides, R. vaniniae, and Stridulivelia quadrispinosa are recorded for the first time from Rio de Janeiro State. Additional new municipality records in Rio de Janeiro State are presented for Microvelia braziliensis, M. ioana, M. mimula, M. pulchella, Paravelia basalis, P. itatiayana, Rhagovelia accedens, R. agra, R. aiuruoca, R. elegans, R. hambletoni, R. henryi, R. itatiaiana, R. lucida, R. macta, R. modesta, R. novana, R. scitula, R. tenuipes, R. tijuca, R. triangula, and R. zela. Corrections are presented for the previously published distributions of Rhagovelia aiuruoca, R. lucida, R. macta, and R. triangula.

A new Amazonian species from the Drosophila annulimana species group (Diptera, Drosophilidae)

Drosophila caxiuana sp. nov., Drosophila subgenus, is described and illustrated. This new species was collected in the Amazonian Biome (Caquajó river, Portel, Pará, Brazil) and is an atypical species to the group due the unusual morphology of the male terminalia.

Do fly parasites of bats and their hosts coevolve?speciation in Trichobius phyllostomae group (Diptera, Streblidae) and their hosts (Chiroptera, Phyllostomidae) suggests that they do not

We examined whether, like many parasite-host systems of coevolution, a group of obligate parasitic bat flies (Trichobius phyllostomae Kessel and related species) cospeciate with their hosts. We first did a cladistic analysis of the T. phyllostomae group and combined that analysis with a phylogenetic hypothesis from the literature for the Stenodermatinae bats. The cladistic analysis included, as outgroups, one species from each morphological group and complex of Trichobius Gervais, and one species from the following genera: Paratrichobius Miranda-Ribeiro, Megistopoda Macquart, Megistapophysys Dick & Wenzel, Neotrichobius Wenzel & Aitken, Speiseria Kessel and Strebla Wiedemann. The cladogram was rooted with a species of Strebla in the subfamily Streblinae. One cladogram was obtained and which found Trichobius to be polyphyletic. The phylogenetic hypothesis as follows: (Paratrichobius, (Neotrichobius, (Megistopoda, Megistapophysis)))) is the sister-group of the phyllostomae group and the following relationships within the ingroup, (((T. vampyropis Wenzel, Trichobius sp. 2) ((T. hispidus Wenzel, T. petersoni Wenzel) ((Trichobius sp. 1 (T. phyllostomae, T. brennani Wenzel))))). When we compared phylogenies through historical association analyses, cospeciation was uncommon, while host-switching was more common and better explained the association between the phyllostomae group and their bat hosts.

Notes on social wasps of the group of Mischocyttarus(Omega) punctatus (Ducke), with description of six new species (Hymenoptera, Vespidae, Polistinae)

ABSTRACTA revision of the taxonomic status and an identification key for wasp species of the genus Mischocyttarus related to M. punctatus (Ducke, 1904) are presented here. Six new species are proposed (M. tayrona Silveira sp. nov.; M. anchicaya Silveira sp. nov.; M. caxiuana Silveira sp. nov.; M. verissimoi Silveira sp. nov.; M. rodriguesi Silveira sp. nov.; M. ryani Silveira sp. nov.), raising to nine the number of species in the M. punctatus group. The highest diversity of the group concentrates in northern South America, in Andean areas and Amazonia. New information concerning the very peculiar nests of these wasps is also given.

A new species of Aguna Williams (Lepidoptera, Hesperiidae) from Panamá belonging to the “claxon group”

ABSTRACT A new species of Aguna Williams, 1927 from Panamá is described: Aguna prasinus Siewert, Leviski, Mielke & Casagrande, sp. nov. Illustrations of adults and male genitalia are provided. A dichotomous key for the male Aguna species for the “claxon group” is also provided.

HETEROTIC GROUP FORMATION IN PSIDIUM GUAJAVA L. BY ARTIFICIAL NEURAL NETWORK AND DISCRIMINANT ANALYSIS

ABSTRACT The present study aimed at evaluating the heterotic group formation in guava based on quantitative descriptors and using artificial neural network (ANN). For such, we evaluated eight quantitative descriptors. Large genetic variability was found for the eight quantitative traits in the 138 genotypes of guava. The artificial neural network technique determined that the optimal number of groups was three. The grouping consistency was determined by linear discriminant analysis, which obtained classification percentage of the groups, with a value of 86 %. It was concluded that the artificial neural network method is effective to detect genetic divergence and heterotic group formation.

O relevante papel do agente sililante na modificação de superfícies de polímeros

The applicability of the silylant agents of the general formula Y3Si-R-X, depends on the reactivity of Y group (halide or alcoxide) attached to silicon and the organic function X (halide, amine, thiol, cyanide, etc) in the extreme position of the chain. Both groups are linked together by an organic chain R, containing usually three methylene groups. A series of these agents can be covalently bonded to an inorganic matrix, since the available OH groups are distributed on the surface, making silica gel the most common support. However, other inorganic oxides, zeolites, lamellar inorganic phosphates and chrysotile can also have these agents anchored. Some illustration are presented for immobilized surface in the use as extractors of cations from dilute aqueous or non-aqueous solutions, catalysts agents, ionic exchanged materials, support for enzyme immobilization, chromatographic applications, use in some industrial features and in many other areas. The evolution of this exciting research field to produce new materials, for many tecnological applications, is strongly dependent on the development of a sensible systematic process for the synthesis of a series of new specific silylant agents.

Simultaneous determination of B-Group vitamins in enriched cookies

The objective of this research was to determine the levels of enrichment of vitamins B1, B2, B6 and B3 in different types and brands of enriched cookies. The chromatographic separation was performed in a C18 column with gradient elution and UV detection at 254 and 287 nm. The results show that only 5 of the 24 brands evaluated are in accordance with the Brazilian legislation with respect to the vitamin content declared on the labels. However, consumption of approximately 100-150 g of most of the brands supplies the recommended dietary intake for children and adults of the vitamins evaluated.

Spectrophotometric and spectrofluorimetric determination of some drugs containing secondary amino group in bulk drug and dosage forms via derivatization with 7-Chloro-4-Nitrobenzofurazon

Sensitive and selective spectrophotometric and spectrofluorimetric methods have been developed for determination of some drugs such as Pramipexole, Nebivolol, Carvedilol, and Eletriptan, which commonly contain secondary amino group. The subject methods were developed via derivatization of the secondary amino groups with 7-Chloro-4-Nitrobenzofurazon in borate buffer where a yellow colored reaction product was obtained and measured spectrophotometrically or spectrofluorimetrically. Concentration ranges were found as 2.0 to 250 μg mL-1 and 0.1 to 3.0 μg mL-1, for spectrophotometric and spectrofluorimetric study, respectively. The described methods can be easily applied by the quality control laboratories in routine analyses of these drugs in pharmaceutical preparations.

Complete ¹H and 13C NMR structural assignments for a group of four goyazensolide-type furanoheliangolides

Four goyazensolide-type sesquiterpene lactones - lychnofolide, centratherin, goyazensolide and goyazensolide acetate - were thoroughly studied by NMR experimental techniques. ¹H NMR, 13C NMR {¹H}, COSY, HMQC, HMBC, J-res. and NOE experiments were performed to provide the needed structural information. Complete and unequivocal assignment, including the determination of all multiplicities, was obtained for each structure and the data collections are presented in tables.

Spectroscopic analysis of C80 doping with group III and group V elements using semiempirical PM3 molecular modelling technique

Semiempirical calculations at the level of PM3 of theory were carried out to study the structural and electronic properties of C80 and some of its doped derivatives with the elements of group III and V at the level of PM3 of theory. We have selected these elements to be substituted in the fullerene-C80 cage in order to show the effect of such structural change on the electronic properties of the molecules studied. The theoretical IR spectra, some of physical and chemical properties of the molecules studied are obtained and discussed.

Evaluation of group electronegativities and hardness (softness) of group 14 elements and containing functional groups through density functional theory and correlation with NMR spectra data

Quantum Chemical calculations for group 14 elements of Periodic Table (C, Si, Ge, Sn, Pb) and their functional groups have been carried out using Density Functional Theory (DFT) based reactivity descriptors such as group electronegativities, hardness and softness. DFT calculations were performed for a large series of tetracoordinated Sn compounds of the CH3SnRR'X type, where X is a halogen and R and R' are alkyl, halogenated alkyl, alkoxy, or alkyl thio groups. The results were interpreted in terms of calculated electronegativity and hardness of the SnRR'X groups, applying a methodology previously developed by Geerlings and coworkers (J. Phys. Chem. 1993, 97, 1826). These calculations allowed to see the regularities concerning the influence of the nature of organic groups RR' and inorganic group X on electronegativities and hardness of the SnRR'X groups; in this case, it was found a very good correlation between the electronegativity of the fragment and experimental 119Sn chemical shifts, a property that sensitively reflects the change in the valence electronic structure of molecules. This work was complemented with the study of some compounds of the EX and ER types, where E= C, Si, Ge, Sn and R= CH3, H, which was performed to study the influence that the central atom has on the electronegativity and hardness of molecules, or whether these properties are mainly affected for the type of ligand bound to the central atom. All these calculations were performed using the B3PW91 functional together with the 6-311++G** basis set level for H, C, Si, Ge, F, Cl and Br atoms and the 3-21G for Sn and I atoms.

A simple spectrophotometric method for the determination of captopril in pharmaceutical preparations using ammonium molybdate

A simple, rapid and sensitive spectrophotometric method for the determination of captopril (CPT) in pharmaceutical formulations is proposed. This method is based on the reduction reaction of ammonium molybdate, in the presence of sulphuric acid, for the group thiol of CPT, producing a green compound (λ max 407 nm). Beer's law is obeyed in a concentration range of 4.60 x 10-4 - 1.84 x 10-3 mol l-1 of CPT with an excellent correlation coefficient (r = 0.9995). The limit of detection and limit of quantification were 7.31 x 10-6 e 2.43 x 10-5 mol l-1 of CPT, respectively. The proposed method was successfully applied to the determination of CPT in commercial brands of pharmaceuticals. No interferences were observed from the common excipients in the formulations. The results obtained by the proposed method were favorably compared with those given by the official reported method at 95 % confidence level.

Group mentoring for junior medical students: perceptions of mentees and mentors

Entering medical school can be associated with a number of difficulties that can hinder students' performance. Mentoring programs are designed to help students circumvent difficulties and improve their learning and personal development. The current study aimed to evaluate the perceptions of both students and mentors regarding a recently introduced, group-based mentoring program designed to support first-year students. After one year of regular meetings, students and mentors' perceptions of the program were assessed by means of structured questionnaires. Response content categories were identified through multiple readings. Both regular attendees and non-participating students had positive opinions about the program. Mentors were highly satisfied at having participated and acknowledged that the program has been useful not only for assisting students, but also for fostering their own personal and professional development. In conclusion, the group-based mentoring program is feasible and can elicit positive views from both mentors and students. In addition, faculty members' participation as mentors can also be beneficial, since the program appears to contribute to their own personal and professional development