Spatial Variability of CO2 Emissions from Newly Exposed Paraglacial Soils at a Glacier Retreat Zone on King George Island, Maritime Antarctica

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Growth of the speckled swimming crab, Arenaeus cribrarius (Lamarck, 1818) (Crustacea, Brachyura, Portunidae), in Ubatuba (SP), Brazil

A total of 2629 individuals of Arenaeus cribrarius (1293 males and 1336 females) were captured in Ubatuba (SP), from August 1996 to July 1997. Individuals were distributed in 5 mm size class carapace width (CW), to verify sex-specific growth-age equations. The Von Bertalanffy model was chosen to determine the growth rate and expressed by CW=120.52[1-e(-1.80t)] for males and CW=100.81[1-e(-1.60t)] for females. The age estimated for the first juvenile stage (t(o)) was 6.1 and 8.3 days for males and females, respectively. The maximum age determined was 1.8 years for males and 2 years for females, which correspond to a maximum size of 115.8 and 96.7 mm, respectively. The maximum size (CWmax) estimated using 95% of asymptotic size was 114.5 mm for males and 95.8 mm for females. Males have a precocious sexual maturity (5 months) when compared to females (6.8 months). The growth rate and size of A. cribrarius are higher than other portunid species, with great interest for aquaculture.

Fecundity and reproductive output of the speckled swimming crab Arenacus cribrarius (Lamarck, 1818) (Brachyura, Portunidae)

Areanaeus cribrarius females were collected over a 12-month period with otter-trawl nets in the Ubatuba littoral zone, Brazil. Ovigerous individuals were measured (CW = carapace width excluding lateral spines) and weighed (WW = wet weight). Each egg brood was weighed (WE = wet weight), dried, and the number of eggs (EN) counted. Scatterplots from EN/CW, EN/WW, and EN/WE were submitted to regression analyses. Mean relative fecundity ((F) over bar') was calculated in each month/season to assess seasonal variation of reproductive intensity. The number of eggs showed a positive correlation with CW, WW, and WE. Fecundity of A. cribrarius ranged from 135,210 to 682,156 eggs, intermediate in comparison with other portunids. Fecundity in Portunidae is typically high; lower values are found in Polybiinae and higher ones in Portuninae. Mean fecundity did not reveal significant differences over months and seasons, but reproductive activity tended to be more intense in summer and winter, a phenomenon related to reduced temperature oscillations as found in subtropical regions.

Ultramorphology of digestive tract of Anticarsia gemmatalis (Hubner, 1818) (Lepidoptera : Noctuidae) at final larval development

The digestive tract of insects is an important natural, physical, and chemical defense barrier against pathogen invasion. Certain. lepidopteran caterpillars are serious pests of agricultural crops and their biology has received much attention, but little is known about the larval noctuid gut. The morphological analysis of the digestive tract in Anticarsia gemmatalis under scanning electron microscopy (SEM) is a good model for studies about its defense mechanism. The material was fixed (2,5% glutaraldehyde solution; 0.1 M-phosphate buffer, pH 7.3), post-fixed (1% osmium tetroxide in the same buffer), dried at critical point, gold coated and analyzed in a SEM 515-Philips. A. gemmatalis digestive tract consists of a straight duct of varying length and diameter, subdivided in three main regions: the foregut formed by the oral cavity, pharynx, esophagus, and crop; the midgut that is the largest portion of the digestive tract without noticeable morphological differentiation along its length; and the hindgut that is morphologically differentiated in pylorus, ileum, colon, and rectum. Although the general morphology of the A. gemmatalis digestive tract is quite similar to the other Lepidoptera species, the anatomical array of the crop muscular layers is quite different comparing with the description for other larval insect.

Juvenile development and growth patterns in the mud crab Eurytium limosum (Say, 1818) (Decapoda, Brachyura, Xanthidae) under laboratory conditions

The post-larval development of the mud crab Eurytium limosum was studied under laboratory conditions by using the offspring of ovigerous females collected at the Comprido River mangrove, SP, Brazil. The first crab stage is fully described and the juvenile development, until crab stage 10, is examined with emphasis on morphological change, sexual differentiation and growth patterns. The carapace of the first crab stage is nearly square as observed in other xanthids, becoming similar to adults only at stage 15. The sexes can be distinguished from stage four, based on the number of pleopods and their morphology. While the intermoult period increases, the moult percentage decreases at each stage. The abdominal allometric growth is sex-dependent, with males showing a negative (b=0.71) and females an isometric (b=0.95) relative growth pattern. Male gonopods undergo a positive allometric growth, and their shape changes remarkably until sexual maturity. The cheliped dentition can be observed after stage 4. Regardless of sex, most crabs have a molariform right cheliped, which is thought to aid the handling of asymmetric prey such as gastropods.

Reproductive behavior of the swimming crab Arenaeus cribrarius (Lamarck, 1818) (Crustacea, Brachyura, Portunidae) in captivity

In this study, the reproductive behavior exhibited by Arenaeus cribrarius in captivity was described, and the duration of each behavioral stage was measured. Swimming crabs were trawled in Ubatuba, northern littoral of São Paulo State, Brazil, and maintained in aquaria. Water conditions and food items were provided according to this species' natural requirements in the wild. In the presence of premolt females, intermolt males exhibited a courtship display that became intensified when the potential mate was visually perceived. After mate selection, the male carried the female under itself (precopulatory position) for 29.8 +/- 5.1 d until the female molted. Afterwards, the male manipulated the recently molted female, and inverted her position under itself as to penetrate her with his first pair of pleopods (copulation), a process that took 17.1 +/- 4.6 h. After copulation the male continued to carry his soft-shelled mate for 29.7 +/- 5.8 d (postcopulatory position). The time elapsed between copulation and spawning was 57.8 +/- 3.8 d and the time interval between successive spawns 33.8 +/- 7.1 d. Total embryonic development took 13.5 +/- 2.1 d in temperature conditions of 25.0 +/- 2.0 degrees C. During the last 4.7 +/- 1.4 d embryos' eyes were already visible. The reproductive behavior pattern in A. cribrarius is very similar to those previously described in other portunids.

Sexual maturity of the speckled swimming crab Arenaeus cribrarius (Lamarck, 1818) (Decapoda, Brachyura, Portunidae), in the Ubatuba Littoral, São Paulo state, Brazil

The sizes at morphological and physiological maturity of male and female Arenaeus cribrarius were estimated to determine if both events are synchronous. Animals were captured with otto-trawls at Ubatuba, Brazil. A total of 2356 specimens, 977 males and 1379 females, were obtained. The major carapace width without spines (CW), the propodus length of the major cheliped (PL) and the width of the 5th abdominal somite (AW) were measured with vernier calipers. Allometric relationships and gonadal development were analyzed to determine the maturity in both sexes. The size at the onset of male morphological maturity was estimated at CW 52 mm, smaller than the CW 63.4 mm physiological maturity size observed. For females, these events are synchronous since both estimates converged at CW 59.7 mm. The onset of functional sexual maturity in A. cribrarius at CW 63.4 and 59.7 mm in males and females, respectively, would indicate a minimum size of CW 64 mm for fishing purposes. Differences between allometric and gonadal estimates indicate the importance of considering both methods. A comparison of the present results with other available data in portunid crabs is provided.

Sexual maturity of Eurytium limosum (say 1818) from a subtropical mangrove in Brazil

The size at onset of maturity of Eurytium limosum from a subtropical mangrove in Brazil was investigated. In this species, sexual maturity for males can be indicated by the allometric growth and gonopod length. For females, the morphological sexual maturity can only be externally verified through the relative quantity of setae along the abdominal margins and pleopods. Internally, gonad development was also examined. The size at which half of the population is physiologically mature was 11.6 mm of CW for females and 12.3 mm of CW for males. The values for the morphological and physiological maturity are very similar, indicating that the development of the secondary sexual characters is synchronized with the achievement of the physiological maturity for E. limosum.

Predation of Platyrrhinus lineatus (E. Geoffroy, 1810) (Chiroptera: Phyllostomidae) by Cyanocorax chrysops (Vieillot, 1818) (Passeriformes: Corvidae).

The predation on vertebrates by birds, including bats, is very common in some families (Accipitridae, Falconidae, Tytonidae, Strigidae), constituting their main diet. For other families (except those that feed strictly on fish), it is occasional and sometimes a matter of opportunity. Here we recorded the predation on a bat (Platyrrhinus lineatus) by the neotropical bird plush-crested jay (Cyanocorax chrysops). on July 26, 2009, around 11:00 am, we recorded an individual of C. chrysops taking part of a P. lineatus on its beak. This record occurred on Jacarezinho Farm (Valparaiso [long dash] SP). The prey species identification was done by visual observation, considering the bat size and its external morphology, especially by the presence of the white dorsal bright stripe. Probably, Platyrrhinus lineatus behavior, which involves living together or in couples on tree canopies, made the capture by the plush-crested jay easier. This is a new record for the diet of C. chrysops and highlights the necessity of additional studies related to birds diet in the Neotropics, even the more conspicuous ones.

The Wigner function associated with the Rogers-Szego polynomials

A Wigner function associated with the Rogers-Szego polynomials is proposed and its properties are discussed. It is shown that from such a Wigner function it is possible to obtain well-behaved probability distribution functions for both angle and action variables, defined on the compact support -pi less than or equal to theta < pi, and for m greater than or equal to 0, respectively. The width of the angle probability density is governed by the free parameter q characterizing the polynomials.

Algebraic properties of Rogers-Szego functions: I. Applications in quantum optics

By means of a well-established algebraic framework, Rogers-Szego functions associated with a circular geometry in the complex plane are introduced in the context of q-special functions, and their properties are discussed in detail. The eigenfunctions related to the coherent and phase states emerge from this formalism as infinite expansions of Rogers-Szego functions, the coefficients being determined through proper eigenvalue equations in each situation. Furthermore, a complementary study on the Robertson-Schrodinger and symmetrical uncertainty relations for the cosine, sine and nondeformed number operators is also conducted, corroborating, in this way, certain features of q-deformed coherent states.

The CMS experiment at the CERN LHC

The Compact Muon Solenoid (CMS) detector is described. The detector operates at the Large Hadron Collider (LHC) at CERN. It was conceived to study proton-proton (and lead-lead) collisions at a centre-of-mass energy of 14 TeV (5.5 TeV nucleon-nucleon) and at luminosities up to 10(34)cm(-2)s(-1) (10(27)cm(-2)s(-1)). At the core of the CMS detector sits a high-magnetic-field and large-bore superconducting solenoid surrounding an all-silicon pixel and strip tracker, a lead-tungstate scintillating-crystals electromagnetic calorimeter, and a brass-scintillator sampling hadron calorimeter. The iron yoke of the flux-return is instrumented with four stations of muon detectors covering most of the 4 pi solid angle. Forward sampling calorimeters extend the pseudo-rapidity coverage to high values (vertical bar eta vertical bar <= 5) assuring very good hermeticity. The overall dimensions of the CMS detector are a length of 21.6 m, a diameter of 14.6 m and a total weight of 12500 t.

Combination of Tevatron Searches for the Standard Model Higgs Boson in the W+W- Decay Mode

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Combined Tevatron upper limit on gg -> H -> W+W- and constraints on the Higgs boson mass in fourth-generation fermion models

We combine results from searches by the CDF and D0 collaborations for a standard model Higgs boson (H) in the process gg -> H -> W+W- in p (p) over bar collisions at the Fermilab Tevatron Collider at root s = 1.96 TeV. With 4.8 fb(-1) of integrated luminosity analyzed at CDF and 5.4 fb(-1) at D0, the 95% confidence level upper limit on sigma(gg -> H) x B(H -> W+W-) is 1.75 pb at m(H) = 120 GeV, 0.38 pb at m(H) = 165 GeV, and 0.83 pb at m(H) = 200 GeV. Assuming the presence of a fourth sequential generation of fermions with large masses, we exclude at the 95% confidence level a standard-model-like Higgs boson with a mass between 131 and 204 GeV.