Characterizing Geo-located Tweets in Brazilian Megacities

This work presents a framework for collecting, processing and mining geo-located tweets in order to extract meaningful and actionable knowledge in the context of smart cities. We collected and characterized more than 9M tweets from the two biggest cities in Brazil, Rio de Janeiro and S\~ao Paulo. We performed topic modeling using the Latent Dirichlet Allocation model to produce an unsupervised distribution of semantic topics over the stream of geo-located tweets as well as a distribution of words over those topics. We manually labeled and aggregated similar topics obtaining a total of 29 different topics across both cities. Results showed similarities in the majority of topics for both cities, reflecting similar interests and concerns among the population of Rio de Janeiro and S\~ao Paulo. Nevertheless, some specific topics are more predominant in one of the cities

NO scavenger CPTIO does not impair maturation by, progesterone but suppresses SNAP effects on metaphase-II arrested eggs.

<p>(A) Effect of CPTIO on meiotic maturation. Histogram showing percentages of matured oocytes (with white spot) after overnight treatment with progesterone (10 µM) either in medium ND96 supplemented 10 mM CPTIO (CPTIO) or oocyte in pure ND96 injected 40 mM CPTIO (injCPTIO). Groups PG + (only progesterone), PG − (without progesterone) and inj water (progesterone and injection 15nl water) was a control of maturation and effect of microinjection. Error bands represent ± SEM values. Different superscripts indicate significant differences (P<0.05). (B) Histogram showing percentages of parthenogenetic activated oocytes after 2 hours treatment with 5 mM SNAP, 10 mM CPTIO or 10 µM A23187 injected or non-injected 40 mM NO scavenger CPTIO or water. Error bands represent ±SEM values. Different superscripts indicate significant differences (P<0.05). Data are shown as mean percentage of activation of five independent experiments. (C) Western blot analysis. After 2 hours ocytes were taken off, homogenized in lysis buffer, and immunoblotted with antibodies against Xp42^Mpk1 and p90^Rsk. (D) Control oocyte in metaphase II arrested oocytes exhibits typical bipolar spindle with chromosomes and the first polar body (nuclear red/picro-indigo carmine staining). (E) Activation after A23187 treatment: typical pronucleus. (F) Oocyte activated by SNAP with pronucleus. (G) Oocyte after SNAP&CPTIO treatment in metaphase II. Scale bars represent 10 µm (D,G) and 40 µm (E,F).</p

Kinetic of SNAP induced activation.

<p>(A) Kinetic of parthenogenetic activation after SNAP treatment. Matured oocytes were cultured with 5 mM SNAP or 10 µM A23187; cortical reaction was scored at 10 minutes time intervals. Data are shown as mean percentage of activation ± SEM of five independent experiments. (B) Western blot analysis. Each time 5 oocytes were taken off, homogenized in lysis buffer, and immunoblotted with antibodies against Cyclin B, P-Tyr15 Cdk1, Xp42^Mpk1 and p90^Rsk. (C) Western blot analysis. Neither Cyclin B or Mos were degraded in SNAP-treated matured oocytes (both were still detected 70 min after the beginning of the treatment); MPF activity was attested by its ability to phosphorylate histone H3. It is to note that Cdk1 remained unphosphorylated at tyrosine 15. (D) Immunoprecipitation. Cdk1 and Cyclin B are complexed together i metaphase II arrested oocytes. SNAP did not induce any separation between the two partners of the MPF heterodimer, even after 70 minutes.</p

Effect of three different nitric oxide donors on parthenogenetic activation of <i>Xenopus laevis</i> matured oocytes.

(A–B)<p>Values with different superscripts within the same row are significantly different.</p>*<p>high concetration of NOR5 strongly increase rate of lytic oocytes.</p><p>Data are shown as mean percentage of activation of five independent experiments for each experimental group.</p

Nitric oxide donor SNAP induces cortical reaction typical of parthenogenetic activation in <i>Xenopus laevis</i> matured oocytes.

<p>(A) Typical morphologies of <i>Xenopus laevis</i> oocytes in control batches, arrested in metaphase II, (B) following parthenogenetic activation by A23187 treatment or (C) following SNAP treatment. Scale bars represent 200 µm. (D) SNAP treatment induces release of cortical granule lectins from <i>Xenopus</i> oocytes. Oocytes were incubated for 1 hour without or with 5 mM SNAP or 10 µM A23187. After 1 hour the fluid surrounding oocytes (15 µl) was collected for analysis by SDS-PAGE and SYPRO Ruby staining. Molecular weight standards are indicated in kDa.</p

Effect of SNAP, A23187 and SNAP+CPTIO on spindle morphogenesis and pronuclear formation following progesterone-induced maturation.

<p>Effect of SNAP, A23187 and SNAP+CPTIO on spindle morphogenesis and pronuclear formation following progesterone-induced maturation.</p

SNAP induced parthenogenetic activation is calcium-dependent.

<p>Effects of 5 mM SNAP application on mature oocyte in ND96 (black triangles) or in ND96 with 50 µM BAPTA-AM (white squares) (A) or in presence of CPTIO (B). Typical results are depicted. Fluorescence was expressed in arbitrary units and background and auto-fluorescence were subtracted. SNAP superfusion, which started at time  = 5 minutes, was responsible for a rise of intracellular calcium fluorescence. The latter was abolished by presence of CPTIO (C) Effect of calcium chelator on SNAP induced activation. Histogram showing percentages of activated oocytes after 2 hours treatment with 5 mM SNAP or 10 uM A23187 supplemented 50 µM or 100 µM BAPTA-AM. Oocyte in control group were treated for 2 hours in clear ND96. Error bands represent ±SEM values. Different superscripts indicate significant diferences (P<0.05). Data are shown as mean percentage of activation of minimally four independent experiments. (D) Percentages of parthenogenetic activated oocytes after 2 hours treatment with 5 mM SNAP in ND96 medium, calcium free medium (CaFree) and calcium limited medium (CaLim). Error bands represent ±SEM values. Different superscripts indicate significant differences (P<0.05). Data are shown as mean percentage of activation of minimally four independent experiments. (E) Western blot analysis. After 2 hours oocytes were taken off, homogenized in lysis buffer, and immunoblotted with antibodies against Xp42^Mpk1 and p90^Rsk. (F) Releasing of nitric oxide in calcium restricted mediums. Nitric oxide contents after SNAP treatment was determined in ND96, CaLim and CaFree mediums by colorimetric measurement of NO nitric oxide metabolites, nitrites and nitrates (NO₃^−/NO₂). Each measurement was repeated three times. Different superscripts indicate significant differences (P<0.05).</p