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Radio-over-fiber (RoF) technology has been employed in network infrastructure due to its large capacity, low attenuation, and low operational costs, as well as due to the possibility of enlarging network coverage. This paper introduces a new approach for the interconnection of wireless sensor network (WSN) by employing RoF links, specifically wireless sensor network based on radio-over-fiber (WSN-RoF). The main contribution of this paper is the introduction of an architecture for the interconnection of WSN and two medium access control (MAC) protocols exclusively tailored to WSN-RoF architecture: scheduling of polling priority MAC and dynamic hybrid MAC for WSNs based on RoF access infrastructure. Both protocols deal with the main problems in WSN-RoF, i.e., the round-trip propagation delay in optical fiber links and the existence of two distinct collision domains: one wireless and the other optical. The performance of these two protocols shows their effectiveness in the interconnection of WSN through RoF links. Results of experiments demonstrate the benefits of using RoF links for the backhaul of WSN.

This work presents a remote monitoring and control solution for a level measurement system. The level measurement system comprises two tanks in a closed loop water circuit, some level transducers, detectors and two actuators. The developed solution is based on microcontrollers and web services. The web interface allows the user to remotely interact with the level measurement and control system.

It is crucial to understand how Neotropical leaf-nosed bats select fruits, because their choices strongly affect the seed dispersal process, especially of pioneer plants. We tested the hypothesis of hierarchical fruit selection by phyllostomid bats at the levels of the bat genus and species by combining a literature database with field experiments. Considering our database for the whole Neotropics, Artibeusbats focus on Ficus(Moraceae) and Cecropia(Cecropiaceae), Carolliabats on Piper(Piperaceae), and Sturnirabats on Solanum(Solanaceae). Results from a field experiment in Brazil corroborated those preferences, because bats of those 3 genera selected 1st the fruits of their preferred plant genera, even when secondary fruits were offered in higher abundance. In another field experiment in Panama, we observed that 2 sympatric Carolliaspecies, although focusing on the same plant genus, prefer different Piperspecies. Literature records for the whole range of the 2 Carolliaspecies show that they have strongly nested diets. Our findings corroborate the hypothesis that frugivorous phyllostomids do not forage opportunistically, and, moreover, segregate their diets hierarchically at the genus and species levels.

Yttrium-doped barium zirconate protonic conductors were synthesized by a two-step route consisting on diffusing barium ions into previously prepared yttrium-doped zirconia. The evolution of the structural phase content was followed by in situ high temperature X-ray diffraction in the room temperature-1200C and by X-ray diffraction analysis of a mixture of cubic yttria-stabilized zirconia and barium carbonate heat treated at high temperatures. The attainment of the BaZr0.85Y0.15O3-delta composition was evaluated by X-ray fluorescence measurements. Pellets sintered at 1500C had the electrical behavior under humidified argon studied by impedance spectroscopy in the 300-600C in the 40 Hz-110 MHz frequency range. Unitary planar solid oxide fuel cells La0,6Sr0,4Fe0,8Co0,2O3/BaZr0.85Y0.15O3-delta/Pt were assembled for measuring the output voltage under operation with hydrogen, methane and ethanol as fuels and air as the oxidant.

Yttrium-doped barium zirconate protonic conductors were synthesized by a two-step route consisting on diffusing barium ions into previously prepared yttrium-doped zirconia. The evolution of the structural phase content was followed by in situ high temperature X-ray diffraction in the room temperature-1200C and by X-ray diffraction analysis of a mixture of cubic yttria-stabilized zirconia and barium carbonate heat treated at high temperatures. The attainment of the BaZr0.85Y0.15O3-delta composition was evaluated by X-ray fluorescence measurements. Pellets sintered at 1500C had the electrical behavior under humidified argon studied by impedance spectroscopy in the 300-600C in the 40 Hz-110 MHz frequency range. Unitary planar solid oxide fuel cells La0,6Sr0,4Fe0,8Co0,2O3/BaZr0.85Y0.15O3-delta/Pt were assembled for measuring the output voltage under operation with hydrogen, methane and ethanol as fuels and air as the oxidant.

Heterogeneous amounts of Hb H have been detected in peripheral blood of alpha-thalassemic patients even when they carry the same mutation association. This suggests the involvement of other modulating factors besides the thalassemia determinants. To address this issue, we investigated differential gene expression in reticulocytes from two Brazilian siblings of mixed ethnical origin (Chinese and African) in whom Hb H disease is caused by the -a3.7/--SEA genotype. One is a 21-year-old male, and the other a 19-year-old female. Their hemoglobin H levels are 18.7 and 5.0%, respectively. By using the mRNA differential-display reverse-transcription polymerase chain reaction (DDRT-PCR) and suppression subtractive hybridization (SSH) techniques, we identified two main transcripts in both procedures, one corresponding to the phosphatidylinositol-4-phosphate-5-kinase type II-alpha (PIP5KIIA) gene and the other corresponding to the beta-globin gene, both overexpressed in the patient with the higher percentage of Hb H. This result was validated by quantitative RT-PCR using two endogenous genes (GAPDH and BAC). PIP5KIIA expression, in arbitrary units (AU), was 0.108701 in the patient with the higher Hb H, 0.031646 in the other and 0.01561 in the normal control, while beta-globin gene expression was 1.13882, 0.71080 and 0.37631 AU, respectively. Reticulocyte RNA samples obtained from three beta-thalassemia intermedia patients showed a very low level of PIP5KIIA expression. Type II PIP kinases produce phosphatidylinositol 4.5 biphosphate (PI4.5P2) by phosphorylating phosphatidylinositol-5-phosphate. PI4.5P2 is a pleiotropic regulatory molecule involved in diverse cellular activities, including modulation of actin cytoskeleton, protein localization and gene expression. Our results suggest that PIP5KIIA may be one of the factors related to the beta-globin gene expression and to the different levels of Hb H in alpha-thalassemic patients. Its exact mechanism of action, however, remains to be determined.

Heterogeneous amounts of Hb H have been detected in peripheral blood of alpha-thalassemic patients even when they carry the same mutation association. This suggests the involvement of other modulating factors besides the thalassemia determinants. To address this issue, we investigated differential gene expression in reticulocytes from two Brazilian siblings of mixed ethnical origin (Chinese and African) in whom Hb H disease is caused by the -a3.7/--SEAgenotype. One is a 21-year-old male, and the other a 19-year-old female. Their hemoglobin H levels are 18.7 and 5.0%, respectively. By using the mRNA differential-display reverse-transcription polymerase chain reaction (DDRT-PCR) and suppression subtractive hybridization (SSH) techniques, we identified two main transcripts in both procedures, one corresponding to the phosphatidylinositol-4-phosphate-5-kinase type II-alpha (PIP5KIIA) gene and the other corresponding to the beta-globin gene, both overexpressed in the patient with the higher percentage of Hb H. This result was validated by quantitative RT-PCR using two endogenous genes (GAPDH and BAC). PIP5KIIA expression, in arbitrary units (AU), was 0.108701 in the patient with the higher Hb H, 0.031646 in the other and 0.01561 in the normal control, while beta-globin gene expression was 1.13882, 0.71080 and 0.37631 AU, respectively. Reticulocyte RNA samples obtained from three beta-thalassemia intermedia patients showed a very low level of PIP5KIIA expression. Type II PIP kinases produce phosphatidylinositol 4.5 biphosphate (PI4.5P2) by phosphorylating phosphatidylinositol-5-phosphate. PI4.5P2 is a pleiotropic regulatory molecule involved in diverse cellular activities, including modulation of actin cytoskeleton, protein localization and gene expression. Our results suggest that PIP5KIIA may be one of the factors related to the beta-globin gene expression and to the different levels of Hb H in alpha-thalassemic patients. Its exact mechanism of action, however, remains to be determined.

Hereditary Persistence of Fetal Hemoglobin is a rare, heterogeneous and benign group of hereditary disorders with an abnormal switch from fetal to adult hemoglobin, resulting in high levels of Hb F in the adult stage. A total of six deletions related to HPFH have been described, associated with increased levels of both gamma chains. Three main hypotheses have been proposed to explain the relationship between these deletions and the non-suppression of gamma genes: the removal of competitive regions that interact with the LCR; the juxtaposition of enhancer elements; and the removal of silencers. Despite evidence to support these hypotheses, however, they are not conclusive. Recently, Xiang and cols (Abstract #1215, 2004 ASH Meeting; Blood, Volume 104, issue 11, November 16, 2004) developed a YAC construct with the whole beta-globin locus containing a deletion of approximately 83.5 Kb responsible for the HPFH-2. Unexpectedly, the gamma gene was completely silenced in the adult transgenic mice. These data suggest that other mechanisms could be involved in the increased levels of HbF in these conditions. The authors speculate that other regions upstream from the cluster may harbor this activity. We, herein, investigate the possible involvement of transcription factors, using the subtractive hybridization method to identify differentially expressed transcripts in reticulocytes from a normal subject and a HPFH-2 subject. We have identified 56 and 106 unique genes in the normal and HPFH-2 cDNA libraries, respectively. Some of these are transcription (zinc fingers and homeobox proteins) and chromatin remodeling (NAP and SWI like proteins) factors that could participate in globin gene regulation. These genes are located in cis or in trans to the deletion and their altered gene expression has been confirmed by Quantitative Real-time PCR in other two HPFH subjects. The data may present new clues about globin gene regulation, the increased expression of gamma gene in deletional HPFH and the dynamic organization of genes and chromosomes in cells.

Hereditary Persistence of Fetal Hemoglobin is a rare, heterogeneous and benign group of hereditary disorders with an abnormal switch from fetal to adult hemoglobin, resulting in high levels of Hb F in the adult stage. A total of six deletions related to HPFH have been described, associated with increased levels of both gamma chains. Three main hypotheses have been proposed to explain the relationship between these deletions and the non-suppression of gamma genes: the removal of competitive regions that interact with the LCR; the juxtaposition of enhancer elements; and the removal of silencers. Despite evidence to support these hypotheses, however, they are not conclusive. Recently, Xiang and cols (Abstract #1215, 2004 ASH Meeting; Blood, Volume 104, issue 11, November 16, 2004) developed a YAC construct with the whole beta-globin locus containing a deletion of approximately 83.5 Kb responsible for the HPFH-2. Unexpectedly, the gamma gene was completely silenced in the adult transgenic mice. These data suggest that other mechanisms could be involved in the increased levels of HbF in these conditions. The authors speculate that other regions upstream from the cluster may harbor this activity. We, herein, investigate the possible involvement of transcription factors, using the subtractive hybridization method to identify differentially expressed transcripts in reticulocytes from a normal subject and a HPFH-2 subject. We have identified 56 and 106 unique genes in the normal and HPFH-2 cDNA libraries, respectively. Some of these are transcription (zinc fingers and homeobox proteins) and chromatin remodeling (NAP and SWI like proteins) factors that could participate in globin gene regulation. These genes are located in cisor in transto the deletion and their altered gene expression has been confirmed by Quantitative Real-time PCR in other two HPFH subjects. The data may present new clues about globin gene regulation, the increased expression of gamma gene in deletional HPFH and the dynamic organization of genes and chromosomes in cells.