The foliar chemistry of sugar maple (Acer saccharunz Marsh.), American beech (Fagus grundifolia E... more The foliar chemistry of sugar maple (Acer saccharunz Marsh.), American beech (Fagus grundifolia Ehrh.), and red spruce (Picea rubens Sarg.) was studied from 1993 to 2003 at the Bear Brook Watershed in Maine (BBWM). The BBWM is a paired-watershed forest ecosystem study, with one watershed treated bimonthly since 1989 with ammonium sulfate ((NH4),SO4) at a rate of 25.2 kg N-ha-'-year-'. Foliar N concentrations were higher in all tree species within the treated watershed compared with trees within the reference watershed. Foliar Ca and Mg concentrations were lower in American beech and red spruce within the treated watershed. There were no significant differences in foliar K concentrations between watersheds. Foliar P and Mn concentration differences between watersheds were inconsistent among years. Differences in foliar N concentrations between watersheds declined over time in sugar maple but not in red spruce or American beech. Differences in foliar Ca and Mg concentrations between the treated and reference watersheds increased over time for American beech and red spruce, primarily because of a consistent decline in concentrations of these nutrients in trees within the treated watershed. No temporal trends in foliar Ca and Mg concentration differences between watersheds were observed for sugar maple. RCsum6 : Les caracteristiques chimiques des feuilles d'Crable h sucre (Acer succl~arum Marsh.), de hCtre a grandes feuilles (Fagus granciifoEia Ehrh.) et d'tpinette rouge (Pice~z rubens Sarg.) ont Cte CtudiCes de 1993 B 2003 dans le bassin de Bear Brook, dans le Maine. o i~ se d6roule une Ctude sur I'Ccosystkme forestier h 1'Cchelle du bassin. Cette etude est menCe dans deux bassins jumelCs dont un est trait6 sur une base bimensuelle depuis 1989 avec du sulfate d'ammonium ((NH4),S04) au taux de 25,2 kg ~.ha-'.an-'. La concentration de N dans les feuilles de toutes les espkces d'arbres dans le bassin trait6 etait plus ClevCe comparativement h celle des arbres du bassin tCmoin. La concentration de Ca et Mg dans les feuilles Ctait plus faible chez le hCtre 21 grandes feuilles et I'Cpinette rouge dans le bassin traitC. I1 n'y avait pas de diEtrence significative entre les bassins dans la concentration foliaire de K. Dans Ie cas de la concentration foliaire de P et Mn, la difference entre les bassins n'etait pas consistante d'une annCe h l'autre. La diff6rence dans la concentration foliaire de N entre les bassins a diminuC avec le temps chez I'trable 21 sucre mais pas chez I'epinette rouge ni le hstre B grandes feuiiles. La difference dans la concentration foliaire de Ca et Mg entre les bassins trait6 et tCmoin a augment6 at7ec le temps chez Ie hCtre a grandes feuilles et 1'Cpinette rouge, surtout 2I cause d'une diminution constante de la concentration de ces nutriments dans les arbres du bassin traitk. Dans le cas de I'Crable 9 sucre, aucune tendance dans le temps n'a Cte observCe dans la diffirence de concentration de Ca et Mg entre les bassins.
Background: This study aimed to compare the effects of intermit-tent and continuous swimming trai... more Background: This study aimed to compare the effects of intermit-tent and continuous swimming training on glucose metabolism in neonatal alloxan treated rats. Methods: Alloxan was injected in newborn rats at 6 days of age (250 mg/kg bw). At 28 days of age, the animals were divided into sedentary alloxan (SA), sedentary control (SC), continuous trained alloxan (CA), intermittent trained alloxan (IA), continuous trained control (CC) and intermittent trained control (IC) groups. The con-tinuous training protocol consisted of 12 weeks swimming (1 h/ day), uninterrupted, fi ve days a week, in individual cylinder tanks (25 cm diameter x 50 cm depth), and with supporting overload of 5 % bw. Intermittent training consisted of 12 weeks of swimming (30 s), interrupted by rest (30 s), in individual cylinder tanks (25 cm diameter x 50 cm depth), for a total of 20 min/day, fi ve days a week, and with an overload of 15 % bw. Results: At 28 days, the alloxan treated animals showed both a higher are...
Piperaceae species have long been used for therapeutic purposes, a reason for the great interest ... more Piperaceae species have long been used for therapeutic purposes, a reason for the great interest in their use as a source of raw material in phytochemical studies. The aim of this work is to investigate the chemical composition and biological potential of Manekia obtusa Miq, a native rare Piperaceae species in Brazil. Phytochemical studies of nonpolar extract from leaves of M. obtusa led to the isolation and characterization of the flavone 7,4'-dimethylapigenine and 2', 6'-dihydroxy-4'-methoxychalcone from the hexane extract. This flavonoid rich fraction was able to inhibit both growth and viability of Leishmania amazonensis in a dose dependent way. Minimum inhibitory concentration (MIC) and inhibitory concentration of 50% (IC 50) were calculated at 49.25 and 26.03 μg/ml, respectively. The leaves and stems of M. obtusa had their essential oils extracted by hydrodistillation and analyzed by gas chromatography-mass spectrometry (GC-MS). The constituents δ-3-carene (55....
2008 IEEE International Conference on Robotics and Biomimetics, 2009
This paper presents the virtual environment implementation for project simulation and conception ... more This paper presents the virtual environment implementation for project simulation and conception of supervision and control systems for mobile robots, that are capable to operate and adapting in different environments and conditions. This virtual system has as purpose to facilitate the development of embedded architecture systems, emphasizing the implementation of tools that allow the simulation of the kinematic conditions, dynamic and control, with real time monitoring of all important system points. For this, an open control architecture is proposal, integrating the two main techniques of robotic control implementation in the hardware level: systems microprocessors and reconfigurable hardware devices. The implemented simulator system is composed of a trajectory generating module, a kinematic and dynamic simulator module and of a analysis module of results and errors. All the kinematic and dynamic results shown during the simulation can be evaluated and visualized in graphs and tables formats, in the results analysis module, allowing an improvement in the system, minimizing the errors with the necessary adjustments optimization. For controller implementation in the embedded system, it uses the rapid prototyping, that is the technology that allows, in set with the virtual simulation environment, the development of a controller project for mobile robots. The validation and tests had been accomplish with nonholonomics mobile robots models with differential transmission.
Objectives: The present study identified the prevalent hepatitis B virus (HBV) genotypes and subt... more Objectives: The present study identified the prevalent hepatitis B virus (HBV) genotypes and subtypes in patients from the Brazilian state of Pará. Materials: A sample of 40 patients infected with HBV was selected from a special facility in Belém between January, 2007, and December, 2008. Clinical, biochemical, serological, virological and pathological variables were used to classify patients as inactive carriers and those with chronic hepatitis, either with or without cirrhosis. Serological tests were performed using enzyme immunoassays and viral DNA sequences and the viral load were assessed using PCR. The HBV genotypes were identified through the sequencing of the S region. Results: All but two of the patients sequenced were genotype A, of which, 92% were A1 and 8% A2. The other two patients were genotype D. The A1 samples were either subtype ayw1 or adw2, while the A2 and D subjects were adw2 and ayw3, respectively. The prevalence of genotype A was 90.5% in group A and 100% in group B. Conclusion: No association was found between genotype and the clinical outcomes of the HBV infection.
Bladder cancer is a significant health problem in rural areas of Africa and the Middle East where... more Bladder cancer is a significant health problem in rural areas of Africa and the Middle East where Schistosoma haematobium is prevalent, supporting an association between malignant transformation and infection by this blood fluke. Nevertheless, the molecular mechanisms linking these events are poorly understood. Bladder cancers in infected populations are generally diagnosed at a late stage since there is a lack of non-invasive diagnostic tools, hence enforcing the need for early carcinogenesis markers. Forty-three formalin-fixed paraffin-embedded bladder biopsies of S. haematobium-infected patients, consisting of bladder tumours, tumour adjacent mucosa and pre-malignant/malignant urothelial lesions, were screened for bladder cancer biomarkers. These included the oncoprotein p53, the tumour proliferation rate (Ki-67>17%), cell-surface cancer-associated glycan sialyl-Tn (sTn) and sialyl-Lewisa/x (sLea/sLex), involved in immune escape and metastasis. Bladder tumours of non-S. haemat...
Abstract: In order to investigate some of the physical consequences of the existence of a minimal... more Abstract: In order to investigate some of the physical consequences of the existence of a minimal length, we propose to include it in the framework of Quantum Mechanics by modifying the Heisenberg algebra, so that a minimum non-zero value for the uncertainty $\ ...
This study investigated whether skin conductance responsivity is associated with selective attent... more This study investigated whether skin conductance responsivity is associated with selective attention assessed by the Stroop Color Word Test (SCWT) in schizophrenia patients. The subjects (31 schizophrenia patients and 20 patients with other psychotic diagnoses) were selected from among inpatients of a general hospital psychiatric ward or day hospital attendees. They were matched with 31 healthy volunteers. The patients began experimental sessions immediately after remission of an acute episode. The three groups of participants were subdivided according to electrodermal responsivity into nonresponsive (NR) and responsive (R) groups. After the psychophysiological recording, the SCWT was applied. Results indicated that on the SCWT, the error interference of the NR schizophrenia group was significantly higher than that of all the other groups. Furthermore, the NR schizophrenia patients had significantly more negative symptoms than the R schizophrenia patients. These results suggest that there is a homogeneous subgroup of schizophrenia patients characterized by low neurovegetative responsiveness to external stimuli, predominance of negative symptoms, and selective attention deficit.
A common assumption in bioclimatic envelope modeling is that species distributions are in equilib... more A common assumption in bioclimatic envelope modeling is that species distributions are in equilibrium with contemporary climate. A number of studies have measured departures from equilibrium in species distributions in particular regions, but such investigations were never carried out for a complete lineage across its entire distribution. We measure departures of equilibrium with contemporary climate for the distributions of the world amphibian species. Specifically, we fitted bioclimatic envelopes for 5544 species using three presence-only models. We then measured the proportion of the modeled envelope that is currently occupied by the species, as a metric of equilibrium of species distributions with climate. The assumption was that the greater the difference between modeled bioclimatic envelope and the occupied distribution, the greater the likelihood that species distribution would not be at equilibrium with contemporary climate. On average, amphibians occupied 30% to 57% of their potential distributions. Although patterns differed across regions, there were no significant differences among lineages. Species in the Neotropic, Afrotropics, Indo-Malay, and Palaearctic occupied a smaller proportion of their potential distributions than species in the Nearctic, Madagascar, and Australasia. We acknowledge that our models underestimate non equilibrium, and discuss potential reasons for the observed patterns. From a modeling perspective our results support the view that at global scale bioclimatic envelope models might perform similarly across lineages but differently across regions.
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Papers by Jose Alex QC