Effect of solar cycle 23 in foF2 trend estimation

The effect of including solar cycle 23 in foF2 trend estimation is assessed using experimental values for Slough (51.5°N, 359.4°E) and Kokobunji (35.7°N, 139.5°E), and values obtained from two models: (1) the Sheffield University Plasmasphere-Ionosphere model, SUPIM, and (2) the International Reference Ionosphere, IRI. The dominant influence on the F2 layer is solar extreme ultraviolet (EUV) radiation, evinced by the almost 90% variance of its parameters explained by solar EUV proxies such as the solar activity indices Rz and F10.7. This makes necessary to filter out solar activity effects prior to long-term trend estimation. Solar cycle 23 seems to have had an EUV emission different from that deduced from traditional solar EUV proxies. During maximum and descending phase of the cycle, Rz and F10.7 seem to underestimate EUV solar radiation, while during minimum, they overestimate EUV levels. Including this solar cycle in trend estimations then, and using traditional filtering techniques, may induce some spurious results. In the present work, filtering is done in the usual way considering the residuals of the linear regression between foF2 and F10.7, for both experimental and modeled values. foF2 trends become less negative as we include years after 2000, since foF2 systematically exceeds the values predicted by a linear fit between foF2 and F10.7. Trends become more negative again when solar cycle 23 minimum is included, since for this period, foF2 is systematically lower than values predicted by the linear fit. foF2 trends assessed with modeled foF2 values are less strong than those obtained with experimental foF2 values and more stable as solar cycle 23 is included in the trend estimation. Modeled trends may be thought of as a ‘zero level’ trend due to the assumptions made in the process of trend estimation considering also that we are not dealing with ideal conditions or infinite time series.Fil: Elias, Ana Georgina. Universidad Nacional de Tucuman. Facultad de Ciencias Exactas y Tecnologia. Departamento de Fisica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: de Haro Barbás, Blas F.. Universidad Nacional de Tucuman. Facultad de Ciencias Exactas y Tecnologia. Departamento de Fisica; ArgentinaFil: Shibasaki, Kiyoto . Nobeyama Solar Radio Observatory; JapónFil: Souza, Jonas R.. Centro de Previsao de Tempo E Estudos Climaticos. Instituto Nacional de Pesquisas Espaciais; Brasi

ANÁLISE QUALI-QUANTITATIVA DA ARBORIZAÇÃO DAS ÁREAS PÚBLICAS DO BAIRRO CENTRO DE RESENDE, RJ

O estudo visou analisar aspectos fitossociológicos arbóreos de 7 áreas públicas do centro do município de Resende-RJ. Foram realizadas visitas as áreas entre os meses de março a maio de 2013 com um formulário para a coleta de dados e uma chave de identificação de espécies. Foram catalogados 171 indivíduos em 18 famílias e 43 espécies. Em relação à Diversidade de Shannon, a Praça do Centenário obteve o maior índice (H'=2,26) em relação às demais áreas avaliadas. O Parque do Aarão obteve o maior índice de Dominância de Simpson (D=11,89). A Praça da Concórdia obteve o maior índice de Equitabilidade de Pielou (J=0,97). A Praça Marechal José Pessoa obteve o menor índice nos três aspectos supracitados (H'=0,79, D=1,65 e J=0,57). Quanto a fitossanidade das árvores, 43,27% dos espécimes foram considerados sadios e, apenas, 12,28% considerados ruins, demonstrando boa qualidade das árvores. A similaridade calculada por Jaccard variou de 0,07 a 0,23, demonstrando uma dissimilaridade entre as áreas estudadas. Tal resultado pode ser devido à utilização de diferentes tipos de modelos paisagísticos pelas gestões municipais em diferentes épocas. As áreas avaliadas apresentaram uma elevada riqueza de espécies e boa qualidade, sendo necessário o conhecimento, respeito e preservação por parte da população

Impairment of the Plasmodium falciparum Erythrocytic Cycle Induced by Angiotensin Peptides

Plasmodium falciparum causes the most serious complications of malaria and is a public health problem worldwide with over 2 million deaths each year. The erythrocyte invasion mechanisms by Plasmodium sp. have been well described, however the physiological aspects involving host components in this process are still poorly understood. Here, we provide evidence for the role of renin-angiotensin system (RAS) components in reducing erythrocyte invasion by P. falciparum. Angiotensin II (Ang II) reduced erythrocyte invasion in an enriched schizont culture of P. falciparum in a dose-dependent manner. Using mass spectroscopy, we showed that Ang II was metabolized by erythrocytes to Ang IV and Ang-(1–7). Parasite infection decreased Ang-(1–7) and completely abolished Ang IV formation. Similar to Ang II, Ang-(1–7) decreased the level of infection in an A779 (specific antagonist of Ang-(1–7) receptor, MAS)-sensitive manner. 10−7 M PD123319, an AT2 receptor antagonist, partially reversed the effects of Ang-(1–7) and Ang II. However, 10−6 M losartan, an antagonist of the AT1 receptor, had no effect. Gs protein is a crucial player in the Plasmodium falciparum blood cycle and angiotensin peptides can modulate protein kinase A (PKA) activity; 10−8 M Ang II or 10−8 M Ang-(1–7) inhibited this activity in erythrocytes by 60% and this effect was reversed by 10−7 M A779. 10−6 M dibutyryl-cAMP increased the level of infection and 10−7 M PKA inhibitor decreased the level of infection by 30%. These results indicate that the effect of Ang-(1–7) on P. falciparum blood stage involves a MAS-mediated PKA inhibition. Our results indicate a crucial role for Ang II conversion into Ang-(1–7) in controlling the erythrocytic cycle of the malaria parasite, adding new functions to peptides initially described to be involved in the regulation of vascular tonus

Impairment of the Plasmodium falciparum Erythrocytic Cycle Induced by Angiotensin Peptides

Plasmodium falciparum causes the most serious complications of malaria and is a public health problem worldwide with over 2 million deaths each year. The erythrocyte invasion mechanisms by Plasmodium sp. have been well described, however the physiological aspects involving host components in this process are still poorly understood. Here, we provide evidence for the role of renin-angiotensin system (RAS) components in reducing erythrocyte invasion by P. falciparum. Angiotensin II (Ang II) reduced erythrocyte invasion in an enriched schizont culture of P. falciparum in a dose-dependent manner. Using mass spectroscopy, we showed that Ang II was metabolized by erythrocytes to Ang IV and Ang-(1–7). Parasite infection decreased Ang-(1–7) and completely abolished Ang IV formation. Similar to Ang II, Ang-(1–7) decreased the level of infection in an A779 (specific antagonist of Ang-(1–7) receptor, MAS)-sensitive manner. 10−7 M PD123319, an AT2 receptor antagonist, partially reversed the effects of Ang-(1–7) and Ang II. However, 10−6 M losartan, an antagonist of the AT1 receptor, had no effect. Gs protein is a crucial player in the Plasmodium falciparum blood cycle and angiotensin peptides can modulate protein kinase A (PKA) activity; 10−8 M Ang II or 10−8 M Ang-(1–7) inhibited this activity in erythrocytes by 60% and this effect was reversed by 10−7 M A779. 10−6 M dibutyryl-cAMP increased the level of infection and 10−7 M PKA inhibitor decreased the level of infection by 30%. These results indicate that the effect of Ang-(1–7) on P. falciparum blood stage involves a MAS-mediated PKA inhibition. Our results indicate a crucial role for Ang II conversion into Ang-(1–7) in controlling the erythrocytic cycle of the malaria parasite, adding new functions to peptides initially described to be involved in the regulation of vascular tonus

Locative Media and Sociability:Using Location-Based Social Networks to Coordinate Everyday Life

Foursquare was a mobile social networking application that enabled people to share location with friends in the form of “check-ins.” The visualization of surrounding known social connections as well as unknown others has the potential to impact how people coordinate social encounters and forge new social ties. While many studies have explored mobile phones and sociability, there is a lack of empirical research examining location-based social network’s (LSBNs) from a sociability perspective. Drawing on a dataset of original qualitative research with a range of Foursquare users, the paper examines the application in the context of social coordination and sociability in three ways. First, the paper explores if Foursquare is used to organize certain social encounters, and if so, why. Second, the paper examines the visualization of surrounding social connections and whether this leads to “serendipitous encounters.” Lastly, the paper examines whether the use of Foursquare can produce new social relationships

In vitro leishmanicidal, antibacterial and antitumour potential of anhydrocochlioquinone A obtained from the fungus Cochliobolus sp

The bioassay-guided fractionation of the ethyl acetate extract of the fungus Cochliobolus sp. highlighted leishmanicidal activity and allowed for anhydrocochlioquinone A (ANDC-A) isolation. MS, 1D and 2D NMR spectra of this compound were in agreement with those published in the literature. ANDC-A exhibited leishmanicidal activity with EC50value of 22.4 \uc2\ub5g/mL (44 \uce\ubcM) and, when submitted to the microdilution assay against Gram-positive and Gram-negative bacteria, showed a minimal inhibitory concentration against Staphylococcus aureus ATCC 25295 of 128 \uce\ubcg/mL (248.7 \uce\ubcM). It was also active against five human cancer cell lines, showing IC50values from 5.4 to 20.3 \uce\ubcM. ANDC-A demonstrated a differential selectivity for HL-60 (SI 5.5) and THP-1 (SI 4.3) cell lines in comparison with Vero cells and was more selective than cisplatin and doxorubicin against MCF-7 cell line in comparison with human peripheral blood mononuclear cells. ANDC-A was able to eradicate clonogenic tumour cells at concentrations of 20 and 50 \uce\ubcM and induced apoptosis in all tumour cell lines at 20 \uce\ubcM. These results suggest that ANDC-A might be used as a biochemical tool in the study of tumour cells biochemistry as well as an anticancer agent with durable effects on tumours

Pentoxifylline associated to hypertonic saline solution attenuates inflammatory process and apoptosis after intestinal ischemia/reperfusion in rats

PURPOSE:To evaluate intestinal inflammatory and apoptotic processes after intestinal ischemia/reperfusion injury, modulated by pentoxifylline and hypertonic saline.METHODS:It was allocated into four groups (n=6), 24 male Wistar rats (200 to 250g) and submitted to intestinal ischemia for 40 min and reperfusion for 80 min: IR (did not receive any treatment); HS group (Hypertonic Saline, 4ml/kg-IV); PTX group (Pentoxifylline, 30mg/kg-IV); HS+PTX group (Hypertonic Saline and Pentoxifylline). All animals were heparinized (100U/kg). At the end of reperfusion, ileal fragments were removed and stained on hematoxylin-eosin and histochemical studies for COX-2, Bcl-2 and cleaved caspase-3.RESULTS:The values of sO2 were higher on treated groups at 40 minutes of reperfusion (p=0.0081) and 80 minutes of reperfusion (p=0.0072). Serum lactate values were lower on treated groups after 40 minutes of reperfusion (p=0.0003) and 80 minutes of reperfusion (p=0.0098). Morphologic tissue injuries showed higher grades on IR group versus other groups: HS (p=0.0006), PTX (p=0.0433) and HS+PTX (p=0.0040). The histochemical study showed lesser expression of COX-2 (p=0.0015) and Bcl-2 (p=0.0012) on HS+PTX group. A lower expression of cleaved caspase-3 was demonstrated in PTX (p=0.0090; PTXvsIR).CONCLUSION:The combined use of pentoxifylline and hypertonic saline offers best results on inflammatory and apoptotic inhibitory aspects after intestinal ischemia/reperfusion.São Paulo University Medical SchoolUSP Medical SchoolFederal University of São Paulo Medical SchoolUSP School of MedicineUSP School of Medicine Department of SurgeryUSP Medical School Department of SurgeryUNIFESP, Medical SchoolSciEL

The Antioxidant Role of Xanthurenic Acid in the Aedes aegypti Midgut during Digestion of a Blood Meal

In the midgut of the mosquito Aedes aegypti, a vector of dengue and yellow fever, an intense release of heme and iron takes place during the digestion of a blood meal. Here, we demonstrated via chromatography, light absorption and mass spectrometry that xanthurenic acid (XA), a product of the oxidative metabolism of tryptophan, is produced in the digestive apparatus after the ingestion of a blood meal and reaches milimolar levels after 24 h, the period of maximal digestive activity. XA formation does not occur in the White Eye (WE) strain, which lacks kynurenine hydroxylase and accumulates kynurenic acid. The formation of XA can be diminished by feeding the insect with 3,4-dimethoxy-N-[4-(3-nitrophenyl)thiazol-2-yl] benzenesulfonamide (Ro-61-8048), an inhibitor of XA biosynthesis. Moreover, XA inhibits the phospholipid oxidation induced by heme or iron. A major fraction of this antioxidant activity is due to the capacity of XA to bind both heme and iron, which occurs at a slightly alkaline pH (7.5-8.0), a condition found in the insect midgut. The midgut epithelial cells of the WE mosquito has a marked increase in occurrence of cell death, which is reversed to levels similar to the wild type mosquitoes by feeding the insects with blood supplemented with XA, confirming the protective role of this molecule. Collectively, these results suggest a new role for XA as a heme and iron chelator that provides protection as an antioxidant and may help these animals adapt to a blood feeding habit

Social autopsy: INDEPTH Network experiences of utility, process, practices, and challenges in investigating causes and contributors to mortality

<p>Abstract</p> <p>Background</p> <p>Effective implementation of child survival interventions depends on improved understanding of cultural, social, and health system factors affecting utilization of health care. Never the less, no standardized instrument exists for collecting and interpreting information on how to avert death and improve the implementation of child survival interventions.</p> <p>Objective</p> <p>To describe the methodology, development, and first results of a standard social autopsy tool for the collection of information to understand common barriers to health care, risky behaviors, and missed opportunities for health intervention in deceased children under 5 years old.</p> <p>Methods</p> <p>Under the INDEPTH Network, a social autopsy working group was formed to reach consensus around a standard social autopsy tool for neonatal and child death. The details around 434 child deaths in Iganga/Mayuge Health and Demographic Surveillance Site (HDSS) in Uganda and 40 child deaths in Dodowa HDSS in Ghana were investigated over 12 to 18 months. Interviews with the caretakers of these children elicited information on what happened before death, including signs and symptoms, contact with health services, details on treatments, and details of doctors. These social autopsies were used to assess the contributions of delays in care seeking and case management to the childhood deaths.</p> <p>Results</p> <p>At least one severe symptom had been recognized prior to death in 96% of the children in Iganga/Mayuge HDSS and in 70% in Dodowa HDSS, yet 32% and 80% of children were first treated at home, respectively. Twenty percent of children in Iganga/Mayuge HDSS and 13% of children in Dodowa HDSS were never taken for care outside the home. In both countries most went to private providers. In Iganga/Mayuge HDSS the main delays were caused by inadequate case management by the health provider, while in Dodowa HDSS the main delays were in the home.</p> <p>Conclusion</p> <p>While delay at home was a main obstacle to prompt and appropriate treatment in Dodowa HDSS, there were severe challenges to prompt and adequate case management in the health system in both study sites in Ghana and Uganda. Meanwhile, caretaker awareness of danger signs needs to improve in both countries to promote early care seeking and to reduce the number of children needing referral. Social autopsy methods can improve this understanding, which can assist health planners to prioritize scarce resources appropriately.</p