A descriptive analysis of the seasonal variation of physical oceanographic characteristics in the northern region of the Todos os Santos Bay (Bahia, Brazil)

The results obtained in the August and December 2003, August 2004 and January 2005 oceanographic campaigns in the northern region of the Todos os Santos Bay (lat. 12º44.5'S; long. 038º35.00'W) between the Madre de Deus and Maré islands are analyzed. Instruments of continuous and discrete samplings were used to measure hydrographic properties currents and tides. The water mass of the northern region of the bay is forced by semidiurnal and mesotides of form number 0.08 and the lunar component M2 height was estimated at 91cm. The time series of the surface currents indicated movements in the N/S direction, forced by the tide with maximum magnitudes of 0.73 m.s-1 on the December 2003 campaign. However, in August 2004 the currents were dominated by the wind stress forcing, with a maximum speed of 1.85 m.s-1 and SE direction. Near the bottom, the influence of the tide is not as evident, with a decrease in intensity due to internal and bottom friction, with a maximum velocity of 0.17 m.s-1. The thermal and haline structures were weakly horizontally, as well as vertically stratified, with extreme values varying in the intervals 23ºC (August, 2004) to 28ºC (December, 2003) and 31.0 psu (August, 2003) to 36.0 psu (December, 2003), respectively. Some conclusions may be drawn from these results: i) The signs of the dilution of the fresh water discharges of the Caípe, Mataripe and São Paulo rivers in the region under the influence of the RLAM were observed only during the winter periods, but in the summer the region was flooded by waters of oceanic origin and the salinities above 36.0 indicated TW mass intrusion; ii) The N-S circulation near the RLAM is strongly dominated by the tide, and the importance of the M2 component was unequivocal, however, the E-W component presented some tidal modulation away from abrupt bottom topographical changes, and iii) The residual series, calculated as the difference between the original and modeled, is about ¼ of the original and confirmed its semidiurnal character.

Shwachman-Kulczycki score still useful to monitor cystic fibrosis severity

INTRODUCTION: The Shwachman-Kulczycki score was the first scoring system used in cystic fibrosis to assess disease severity. Despite its subjectivity, it is still widely used. OBJECTIVE: To study correlations among forced expiratory volume in one second (FEV1), chest radiography, chest computed tomography, 6-minute walk test, and Shwachman-Kulczycki score in patients with cystic fibrosis and to test whether the Shwachman-Kulczycki score is still useful in monitoring the severity of the disease. METHODS: A cross-sectional prospective study was performed to analyze the correlations (Spearman). Patients with clinically stable cystic fibrosis, aged 3-21 years, were included. RESULTS: 43 patients, 19F/24M, mean age 10.5 + 4.7 years, with a median Shwachman-Kulczycki score of 70 were studied. The median Brasfield and Bhalla scores were 17 and 10, respectively. The mean Z score for the 6-minute walk test was -1.1 + 1.106 and the mean FEV1 was 59 + 26 (as percentage of predicted values). The following significant correlations versus the Shwachman-Kulczycki score were found: FEV1 (r = 0.76), 6-minute walk test (r = 0.71), chest radiography (r = 0.71) and chest computed tomography (r = -0.78). When patients were divided according to FEV1, a statistically significantly correlation with the Shwachman-Kulczycki score was found only in patients with FEV1 <70% (r = 0.67). CONCLUSIONS: The Shwachman-Kulczycki score remains an useful tool for monitoring the severity of cystic fibrosis, adequately reflecting the functional impairment and chest radiography and tomography changes, especially in patients with greater impairment of lung function. When assessing patients with mild lung disease its limitations should be considered and its usefulness in such patients should be evaluated in larger populations.

Morfologia dos órgãos genitais masculinos e da cloaca da ema (Rhea americana americana)

As características morfológicas, macroscópicas e microscópicas, dos órgãos genitais masculinos e da cloaca foram analisados em 23 emas, quatro filhotes (duas semanas), sete jovens (de três a oito meses) e doze adultos (três anos), provenientes da Cooperativa Emas do Brasil, RS, e do CEMAS, Mossoró, RN. Os testículos da ema possuem formato alongado e localizam-se na cavidade celomática, na região intra-abdominal dorsal, com comprimento e larguras médias de 7,6±1,2cm e 2,6± 0,7cm nos adultos; 4,5±1,5cm e 0,9±0,4cm nos jovens; e 0,8±0,3cm, e 0,2±0,1cm nos filhotes. O testículo está envolto pela túnica albugínea e seu parênquima possui túbulos seminíferos irregulares, compostos por epitélio espermatogênico e por células de sustentação, e pelo tecido intersticial, com as células endócrinas intersticiais, tecido conjuntivo frouxo e vasos. Nos adultos observaram-se todas as células da linhagem espermatogênica, enquanto nos jovens com 3 meses, os testículos apresentaram túbulos seminíferos com luz reduzidas, espermatogônias e células de sustentação indiferenciadas. Os ductos eferentes possuem um epitélio cúbico ciliado, enquanto no ducto epididimário o epitélio é columnar. O epidídimo apresentou-se alongado e fusiforme junto a margem medial do testículo. O ducto deferentes apresentou trajeto sinuoso nos adultos, retilíneo nos jovens, convoluto na sua porção média, diminuindo seu formato sigmóide em sua porção caudal, próximo à cloaca. O epitélio é pseudoestratificado e reveste a luz irregular nos adultos e circular nos jovens, mantendo proximidade com o ureter. A cloaca dividiu-se em três segmentos: o coprodeu, o urodeo e o proctodeo. No urodeu os ductos deferentes desembocaram em papilas na parede ventro-lateral, próximo a inserção do falo fibroso. O falo é um órgão fibroso linfático, localizado na parede ventral, no assoalho da cloaca, e apresentou duas porções: uma rígida bifurcada e contorcida, e outra simples espiralada e flexível, a qual normalmente esteve invertida. Em exposição forçada, o falo teve 14 cm de comprimento. De forma geral os órgãos reprodutores das emas compartilharam da morfologia de outras aves, principalmente aquelas descritas para os avestruzes.

Eventos de vida produtores de estresse e queixas de insônia entre auxiliares de enfermagem de um hospital universitário no Rio de Janeiro: estudo Pró-Saúde

OBJETIVO: Avaliar a associação entre eventos de vida produtores de estresse (EVPE) e queixas de insônia (QI). MÉTODOS: Foram analisados dados seccionais de 695 auxiliares de enfermagem de um hospital universitário, participantes do Estudo Pró-Saúde - coorte de funcionários de uma universidade no Rio de Janeiro. As informações foram obtidas através de um questionário multidimensional e autopreenchido, que avaliou a ocorrência de EVPE nos últimos 12 meses, variáveis socioeconômicas e demográficas e QI. As QI foram analisadas como desfecho politômico (frequente, ocasional, e ausente). Odds ratios brutos e ajustados foram calculados através de regressão logística multinomial. RESULTADOS: A prevalência total de QI foi de 45,8% (16,7% frequentes e 29,1% ocasionais). Após ajuste por sexo, idade, estado civil, renda familiar per capita e regime de trabalho, os EVPE associados com QI frequentes foram: "rompimento de relação amorosa" (OR = 3,32; IC95% 1,90 - 5,78), "ter tido problemas graves de saúde" (OR = 2,82; IC95% 1,73 - 4,58); "dificuldades financeiras graves" (OR = 2,38; IC95% 1,46 - 3,88), e "mudança forçada de moradia" (OR = 1,97; IC95% 1,02 - 3,79). Com relação às QI ocasionais, houve associação apenas com rompimento de relação amorosa (OR = 2,30; IC95% 1,42 - 3,74) e dificuldades financeiras graves (OR = 1,87; IC95% 1,27 - 2,75). CONCLUSÕES: Dada a responsabilidade com vidas humanas que os auxiliares de enfermagem assumem durante seu horário de trabalho, nossos achados podem contribuir para ações mais efetivas, por parte dos serviços de saúde ao trabalhador, para lidar com o estresse nessa categoria

The Effect of Spatial Scale on Predicting Time Series: A Study on Epidemiological System Identification

A susceptible-infective-recovered (SIR) epidemiological model based on probabilistic cellular automaton (PCA) is employed for simulating the temporal evolution of the registered cases of chickenpox in Arizona, USA, between 1994 and 2004. At each time step, every individual is in one of the states S, I, or R. The parameters of this model are the probabilities of each individual (each cell forming the PCA lattice ) passing from a state to another state. Here, the values of these probabilities are identified by using a genetic algorithm. If nonrealistic values are allowed to the parameters, the predictions present better agreement with the historical series than if they are forced to present realistic values. A discussion about how the size of the PCA lattice affects the quality of the model predictions is presented. Copyright (C) 2009 L. H. A. Monteiro et al.

Pluripotent Reprogramming of Fibroblasts by Lentiviralmediated Insertion of SOX2, C-MYC, and TCL-1A

Reprogramming of somatic cells to pluripotency promises to boost cellular therapy. Most instances of direct reprogramming have been achieved by forced expression of defined exogenous factors using multiple viral vectors. The most used 4 transcription factors, octamer-binding transcription factor 4 (OCT4), (sex determining region Y)-box 2 (SOX2), Kruppel-like factor 4 (KLF4), and v-myc myelocytomatosis viral oncogene homolog (C-MYC), can induce pluripotency in mouse and human fibroblasts. Here, we report that forced expression of a new combination of transcription factors (T-cell leukemia/lymphoma protein 1A [TCL-1A], C-MYC, and SOX2) is sufficient to promote the reprogramming of human fibroblasts into pluripotent cells. These 3-factor pluripotent cells are similar to human embryonic stem cells in morphology, in the ability to differentiate into cells of the 3 embryonic layers, and at the level of global gene expression. Induced pluripotent human cells generated by a combination of other factors will be of great help for the understanding of reprogramming pathways. This, in turn, will allow us to better control cell-fate and apply this knowledge to cell therapy.

Antidepressant activity evaluation of Hypericum brasiliense standardized extract

Hypericum brasiliense (Hypericaceae) is a Brazilian traditional plant used as an excitant, antispasmodic and antiofidic agent in the South and Southeastern areas. Pharmacological studies were performed to evaluate antidepressant effects of standard extract of H. brasiliense (SEHB) alone or combined with fluoxetine (10 mg/kg i. p.), GBR-12909 (10 mg/kg ip) or Trans-2-phenylcyclopropylamine (5 mg/kg ip) using forced swimming test (FST), open field test (OFT) and rota rod assays. In the FST, SEHB reduced in a dose-dependent manner the immobility time, and has shown antagonistic effect when administrated with fluoxetine. In the OFT, SEHB has caused marginal effect of the evaluated parameters (ambulation and rearing), but when associated with fluoxetine or trans-2-phenylcyclopropylamine, the reduction of the parameters was noticed. On rota rod test, SEHB did not produce significant alteration. Based on results we suggest that SEHB has an antidepressant activity.

Modeling Two-Oscillator Circadian Systems Entrained by Two Environmental Cycles

Several experimental studies have altered the phase relationship between photic and non-photic environmental, 24 h cycles (zeitgebers) in order to assess their role in the synchronization of circadian rhythms. To assist in the interpretation of the complex activity patterns that emerge from these ""conflicting zeitgeber'' protocols, we present computer simulations of coupled circadian oscillators forced by two independent zeitgebers. This circadian system configuration was first employed by Pittendrigh and Bruce (1959), to model their studies of the light and temperature entrainment of the eclosion oscillator in Drosophila. Whereas most of the recent experiments have restricted conflicting zeitgeber experiments to two experimental conditions, by comparing circadian oscillator phases under two distinct phase relationships between zeitgebers (usually 0 and 12 h), Pittendrigh and Bruce compared eclosion phase under 12 distinct phase relationships, spanning the 24 h interval. Our simulations using non-linear differential equations replicated complex non-linear phenomena, such as ""phase jumps'' and sudden switches in zeitgeber preferences, which had previously been difficult to interpret. Our simulations reveal that these phenomena generally arise when inter-oscillator coupling is high in relation to the zeitgeber strength. Manipulations in the structural symmetry of the model indicated that these results can be expected to apply to a wide range of system configurations. Finally, our studies recommend the use of the complete protocol employed by Pittendrigh and Bruce, because different system configurations can generate similar results when a ""conflicting zeitgeber experiment'' incorporates only two phase relationships between zeitgebers.

Gravity-Induced Vacuum Dominance

has been widely believed that, except in very extreme situations, the influence of gravity on quantum fields should amount to just small, subdominant contributions. This view seemed to be endorsed by the seminal results obtained over the last decades in the context of renormalization of quantum fields in curved spacetimes. Here, however, we argue that this belief is false by showing that there exist well-behaved spacetime evolutions where the vacuum energy density of free quantum fields is forced, by the very same background spacetime, to become dominant over any classical energy-density component. By estimating the time scale for the vacuum energy density to become dominant, and therefore for back-reaction on the background spacetime to become important, we argue that this (infrared) vacuum dominance may bear unexpected astrophysical and cosmological implications.

The impact of the subtropical South Atlantic SST on South American precipitation

The Community Climate Model (CCM3) from the National Center for Atmospheric Research (NCAR) is used to investigate the effect of the South Atlantic sea surface temperature (SST) anomalies on interannual to decadal variability of South American precipitation. Two ensembles composed of multidecadal simulations forced with monthly SST data from the Hadley Centre for the period 1949 to 2001 are analysed. A statistical treatment based on signal-to-noise ratio and Empirical Orthogonal Functions (EOF) is applied to the ensembles in order to reduce the internal variability among the integrations. The ensemble treatment shows a spatial and temporal dependence of reproducibility. High degree of reproducibility is found in the tropics while the extratropics is apparently less reproducible. Austral autumn (MAM) and spring (SON) precipitation appears to be more reproducible over the South America-South Atlantic region than the summer (DJF) and winter (JJA) rainfall. While the Inter-tropical Convergence Zone (ITCZ) region is dominated by external variance, the South Atlantic Convergence Zone (SACZ) over South America is predominantly determined by internal variance, which makes it a difficult phenomenon to predict. Alternatively, the SACZ over western South Atlantic appears to be more sensitive to the subtropical SST anomalies than over the continent. An attempt is made to separate the atmospheric response forced by the South Atlantic SST anomalies from that associated with the El Nino - Southern Oscillation (ENSO). Results show that both the South Atlantic and Pacific SSTs modulate the intensity and position of the SACZ during DJF. Particularly, the subtropical South Atlantic SSTs are more important than ENSO in determining the position of the SACZ over the southeast Brazilian coast during DJF. On the other hand, the ENSO signal seems to influence the intensity of the SACZ not only in DJF but especially its oceanic branch during MAM. Both local and remote influences, however, are confounded by the large internal variance in the region. During MAM and JJA, the South Atlantic SST anomalies affect the magnitude and the meridional displacement of the ITCZ. In JJA, the ENSO has relatively little influence on the interannual variability of the simulated rainfall. During SON, however, the ENSO seems to counteract the effect of the subtropical South Atlantic SST variations on convection over South America.

Magnetostriction of Fe-Ti Alloys

Longitudinal and transverse magnetostriction measurements were performed on polycrystalline Fe(100-x)Ti(x) alloys, for a large Ti concentration range, from x = 8.8 to 34.7 at.%. Our results showed that substituting Fe by Ti does not significantly enhance the magnetostriction. For all Ti concentrations in the magnetically saturated state, the longitudinal magnetostriction values vary from -2 x 10(-6) to 6 x 10(-6). On the other hand, Fe(100-x)Ti(x) alloys exhibit a large forced volume magnetostriction, which increases with increasing Ti-concentration. The magnetostriction behavior could be explained considering investigations of the hyteresis loops and the microstructure.

Do Larvae and Ovipositing Chironomus riparius (Diptera: Chironomidae) Females Avoid Copper-Contaminated Environments?

Studies on the avoidance behavior of aquatic organisms to contaminants have confirmed that such behavior can be relevant in field situations. However, almost all toxicity tests involve the forced exposure of organisms to toxicants. In particular, despite the importance of Chironomus riparius Meigen larvae in sediment toxicity testing, only a few studies on avoidance behavior have been performed. This study investigated the ability of different life stages of C. riparius, including ovipositing females, first-, second-, and fourth-instar larvae, to avoid copper-contaminated environments. Ovipositing females were given a choice between a control and copper solution (1.3 mg Cu l(-1)). First-instar larvae were provided with a choice between a control and a copper (2.0 mg Cu l(-1))-spiked sediment. Both second- and fourth-instars were exposed to a copper gradient (0.38-3.4 mg Cu l(-1)) in a flow-through system. None of the life stages avoided copper, even though the highest concentrations caused lethal effects on midges. The avoidance behavior of C. riparius is not a sensitive endpoint to assess copper sublethal toxicity.

Piezoceramic Composite Actuators for Flow Control in Low Reynolds Number Airflow

The research presented here employs solid-state actuators for flow separation delay or for forced attachment of separated flow seen in airfoils at low Reynolds numbers. To reduce separation, periodic excitation to the flow around the leading edge of the airfoil is induced by Macro-Fiber Composite actuated clamped-free unimorph benders. An electromechanical model of the unimorph is briefly presented and parametric study is conducted to aid the design of a unimorph to output high deformation at a desired frequency. The optimum frequency and amplitude for lift improvement at post-stall angles are identified experimentally. Along with aerodynamic force and structural displacement measurements, helium bubble flow visualization is used to verify existing separated flow, and the attached flow induced by flow control. The lift enhancement induced by several flow control techniques is compared. A symmetric and non-uniform (3D) flow excitation results in the maximum lift enhancement at post-stall region at the lowest power consumption level. A maximum lift coefficient increase of 27.5% (in the post-stall region) is achieved at 125 Hz periodic excitation, with the 3D symmetric actuation mode at 5 m/s and the reduced frequency of 3.78. C(l,max) is increased 7.6% from the baseline.

Experimental analysis of wheel/workpiece dynamic interactions in grinding

The aim of this work is to study the wheel/workpiece dynamic interactions in high-speed grinding using vitrified CBN wheel and DTG (difficult to grind) work materials. This problem is typical in the grinding of engine valve heads. The influence of tangential force per abrasive grain was investigated as an important control variable for the determination of G ratio. Experiments were carried out to observe the influence of vibrations in the wheel wear. The measurements of acoustic emission (AE) and vibration signals helped in identifying the correlation between the dynamic interactions (produced by forced random excitation) and the wheel wear. The wheel regenerative chatter phenomenon was observed by using the wheel mapping technique. (c) 2008 CIRP.

Floquet stability analysis of the flow around an oscillating cylinder

This investigative work is concerned with the flow around a circular cylinder submitted to forced transverse oscillations. The goal is to investigate how the transition to turbulence is initiated in the wake for cases with different Reynolds numbers (Re) and displacement amplitudes (A). For each Re the motion frequency is kept constant, close to the Strouhal number of the flow around a fixed cylinder at the same Re. Stability analysis of two-dimensional periodic flows around a forced-oscillating cylinder is carried out with respect to three-dimensional infinitesimal perturbations. The procedure consists of performing a Floquet type analysis of time-periodic base flows, computed using the spectral/hp element method. With the results of the Floquet calculations, considerations regarding the stability of the system are drawn, and the form of the instability at its onset is obtained. The critical Reynolds number is observed to change with the amplitude of oscillation. With respect to instabilities, unstable modes with the same symmetry as mode A of a fixed cylinder are observed; however, they present different wavelengths. Also, the instabilities observed for the oscillating cylinder are distinctively stronger in the braid shear layers. Other unstable modes similar to mode B are found. Quasi-periodic modes are observed in the 2S wake, and subharmonic mode occurrences are reported in P + S wakes. (C) 2009 Elsevier Ltd. All rights reserved.