Studies of water-particle flow dynamics in shallow estuarine systems show that tidal currents control water exchange, salt flux and residence time. We used the 3D Estuary, Lake and Coastal Ocean ...Model (ELCOM) to estimate the dynamics of tidal currents, salt flux and residence time in the Macuse Estuary, central Mozambique. The model was calibrated using data acquired from field-data measurements obtained in 2014 with an acoustic Doppler current profiler and conductivity-temperature-depth (CTD) casts and a tide-gauge. The water flow dynamics that were tracked indicated that tidal currents of 100 cm s
−1
were dissipated by friction caused by bathymetric morphology during both the spring and neap tides. The water dissipation was translated into a phase-difference delay of ∼15 min between the catchment zone and the outlet during flood and ebb tides. The study showed that tidal currents and river discharges controlled the salt flux (2.07 × 10
5
g kg
−1
m
3
s
−1
) and the variation in residence time from hours to 40 days. The water ages were mostly driven by U-velocity tidal currents, bathymetric gradients and seasonal river discharges of ∼500 m
3
s
−1
. River discharges seasonally affected salinity changes between 15 and 30, and changes in the concentration of suspended sediments of ∼300 mg l
−1
. In addition, it was shown that ELCOM was able to track the water-particle dynamics well, indicating the model's suitability. These results contribute to our understanding of the effect of water-exchange dynamics on residence time and salt flux in shallow coastal inlet systems.
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BFBNIB, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
•A model of TRIGA IPR-R1 was developed in Serpent 2.1.32 code with ENDF/B-VIII.•The global neutron multiplication factor and the axial neutron flux in the central tube were evaluated and ...compared.•The results were evaluated by comparing the experimental values and a model developed in MCNP5 (ENDF/B-VI).•The axial neutron flux was obtained and compared using MCNP6 (ENDF/B-VI). and Serpent (ENDF/B-VIII) models.•The results are still in good agreement with the experimental values.
With the Serpent 2.1.32 and the ENDF/B-VIII cross-section data library, a simulation model of the TRIGA IPR-R1, a research pool-type reactor located at the Nuclear Technology Development Center (Centro de Desenvolvimento da Tecnologia Nuclear − CDTN) in Belo Horizonte/ Brazil, was developed to perform Monte Carlo simulations to assess neutronic parameters relevant to reactor physics research such as the neutron multiplication factor and axial neutron flux. The simulations were performed with normal operation conditions and during a loss of coolant accident. After analyzing the results obtained, it was possible to validate the model due to the good agreement with former studies and experimental values.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
► Stable Eu3+ and Er3+ barium titanate tellurite glasses were prepared. ► Crystallization studies shown that transparent glass–ceramics can be obtained. ► Barium titanate BaTiO3 is precipitated ...together with another crystalline phase identified as an isostructure of La10Te6O27.3. ► Gold doping is efficient to promote volume nucleation and preferential precipitation of BaTiO3.
The main objective of this work has been to investigate the crystallization behavior of the glass composition 70TeO2–15BaO–15TiO2 doped with Eu3+ and Er3+ in order to check the possibility of obtaining transparent glass–ceramics containing rare earth-doped BaTiO3 nanocrystals. Glass samples with the ternary composition 70TeO2–15BaO–15TiO2 were synthesized by the melt-quenching method and doped with 0.1% of Eu3+ and Er3+. Thermal properties were investigated by DTA and heat-treatments were applied between Tg and Tx to induce the controlled crystallization of these glasses. One-step and two-step heat treatments were tested and the final glass–ceramics characterized by X-ray diffraction and UV–Vis absorption. It has been shown that transparent glass–ceramics can be obtained after heat-treatment but barium titanate BaTiO3 is hardly precipitated without coprecipitation of another crystalline phase identified as an isostructure of lanthanum tellurate. In addition, the crystalline volume fraction is relatively small in these transparent samples. Finally, Gold doping has been shown to be very effective to promote a volume nucleation and preferential crystallization of BaTiO3 over the other crystalline phases.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
In this work, we report preliminary results for Monte Carlo simulations of mono-disperse Fe
3O
4 based nanoparticles. For the low concentration colloids considered in our calculation, we observed ...only the formation of dimers, with a mean particle–particle distance around 0.5
nm for a 9
nm sample, in excellent agreement with magnetic resonance data. However, our calculated dimer concentration does not change with the particle size in disagreement with experimental finds. This is probably related to the fact that the Hamaker constant is considered size independent.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Chagas’ disease (CD) is highly prevalent in South America. Brazilian surgeons and gastroenterologists gained valuable experience in the treatment of CD esophagopathy (chagasic achalasia) due to the ...high number of cases treated. The authors reviewed the lessons learned with the treatment of achalasia by different centers experienced in the treatment of Chagas’ disease. Preoperative evaluation, endoscopic treatment (forceful dilatation and botulinum toxin injection), Heller's myotomy, esophagectomy, conservative techniques other than myotomy, and reoperations are discussed in the light of personal experiences and review of International and Brazilian literature. Aspects not frequently adopted by North American and European surgeons are emphasized. The review shows that nonadvanced achalasia is frequently treated by Heller's myotomy. Endoscopic treatment is reserved to limited cases. Treatment for end‐stage achalasia is not unanimous. Esophagectomy was a popular treatment in advanced disease; however, the morbidity/mortality associated to the procedure made some authors seek different alternatives, such as Heller's myotomy and cardioplasties. Minimally invasive approach to esophageal resection may change this concept, although few centers perform the procedure routinely.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
Abstract
Background
Physical inactivity has been shown to be associated with all-cause mortality in both healthy and unhealthy middle-aged and older individuals. While regular exercise is equally ...recommended for men and women, it is virtually unknown if sex influences the long-term survival among participants of a medically-supervised exercise program (MSEP).
Purpose
To evaluate if cardiovascular and all-cause mortality differs between men and women who participates in a MSEP.
Methods
Retrospective data from an open cohort of individuals aged 36 to 85 years old (66% men) who participated in a private MSEP between March 1994 and December 2018 were analyzed. The participants were free to attend the exercise sessions anytime from 6 a.m. to 9:30 p.m. (Monday to Friday) or 7 a.m. to 4 p.m. (Saturday). In median, the participants completed 47 sessions (1 to 5992 sessions) and attended for 6 months. Exercise sessions last between 60–80 minutes on average and included aerobic, muscle power, flexibility and balance exercises for all participants. Depending on clinical condition, gross and fine motor coordination, inspiratory muscle and isometric handgrip training were also performed under direct supervision of a multiprofessional team. Before each exercise session, the participant was briefly assessed by the exercise physician amd the aerobic exercise part was individually prescribed based on pre-participation evaluation/previous session data. Kaplan-Meier survival curves were separately determined for men and women - cardiovascular and all-cause mortality - and statistically compared by log rank test.
Results
Men and women had identical mean ages of 62.5 years-old (p>0.99) and median follow-up was 11 years, ranging from 0.1 to 24.8 years. From a total of 2,238 participants wit different disorders (68% with coronary artery disease), 465 died (21%), with almost three times higher death rate for men (15.1%) as compared to women (5.7%) (p<0.001). Cardiovascular deaths were 27% of total and also proportionally more frequent in men than women (HR 0.63, 95% CI 0.44–0.9; p=0.012). Women had a higher long-term overall survival rate than men (83% vs. 77%, respectively, HR 0.66, 95% CI 0.55–0.80; p<0.001).
Conclusion
Long-term cardiovascular and all-cause mortality were much higher in men than women that participated in a MSEP and these differences could not be explained by age. Future studies are needed to explain these findings and to analyze if men and women in MSEP would need similar dose of exercise for better survival benefit.
Acknowledgement/Funding
CNPq/FAPERJ/Health State Secretary
Unveiling the enigma of ATLAS17aeu Melandri, A.; Rossi, A.; Benetti, S. ...
Astronomy & astrophysics,
01/2019, Volume:
621
Journal Article
Peer reviewed
Open access
Aims. The unusual transient ATLAS17aeu was serendipitously detected within the sky localisation of the gravitational wave trigger GW 170104. The importance of a possible association with ...gravitational waves coming from a binary black hole merger led to an extensive follow-up campaign, with the aim of assessing a possible connection with GW 170104. Methods. With several telescopes, we carried out both photometric and spectroscopic observations of ATLAS17aeu, for several epochs, between ∼3 and ∼230 days after the first detection. Results. We studied in detail the temporal and spectroscopic properties of ATLAS17aeu and its host galaxy. Although at low significance and not conclusive, we found similarities to the spectral features of a broad-line supernova superposed onto an otherwise typical long-GRB afterglow. Based on analysis of the optical light curve, spectrum, and host galaxy spectral energy distribution, we conclude that the redshift of the source is probably z ≃ 0.5 ± 0.2. Conclusions. While the redshift range we have determined is marginally compatible with that of the gravitational wave event, the presence of a supernova component and the consistency of this transient with the Ep–Eiso correlation support the conclusion that ATLAS17aeu was associated with the long gamma-ray burst GRB 170105A. This rules out the association of the GRB 170105A/ATLAS17aeu transient with the gravitational wave event GW 170104, which was due to a binary black hole merger.
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FMFMET, NUK, UL, UM, UPUK
In the developing mammalian brain, differentiating neurons mature morphologically via neuronal polarity programs. Despite discovery of polarity pathways acting concurrently with differentiation, it's ...unclear how neurons traverse complex polarity transitions or how neuronal progenitors delay polarization during development. We report that zinc finger and homeobox transcription factor-1 (Zeb1), a master regulator of epithelial polarity, controls neuronal differentiation by transcriptionally repressing polarity genes in neuronal progenitors. Necessity-sufficiency testing and functional target screening in cerebellar granule neuron progenitors (GNPs) reveal that Zeb1 inhibits polarization and retains progenitors in their germinal zone (GZ). Zeb1 expression is elevated in the Sonic Hedgehog (SHH) medulloblastoma subgroup originating from GNPs with persistent SHH activation. Restored polarity signaling promotes differentiation and rescues GZ exit, suggesting a model for future differentiative therapies. These results reveal unexpected parallels between neuronal differentiation and mesenchymal-to-epithelial transition and suggest that active polarity inhibition contributes to altered GZ exit in pediatric brain cancers.
Mesenchymal stem cells (MSC) are modern tools in regenerative therapies of humans and animals owed to their immunomodulatory properties, which are activated in a pro-inflammatory environment. ...Different preconditioning strategies had been devised to enhance the immunomodulatory properties of MSC. In this research, we evaluated the immunological attributes of equine adipose MSC (eAMSC) before and after preconditioning in vitro with prostaglandin E2 (PGE2), substance P (SP), their combination and IFNγ. PGE2/SP was the best combination to keep or enhance the mesodermal lineage differentiation of eAMSC. Alongside with this, preconditioning of eMSC with PGE2 and SP did not affect expression of stemness MSC surface phenotype: CD90+, CD44+, MHC class I+, MHC class II− and CD45−, assessed by cytometry. Both naïve and preconditioned eAMSC expressed genes related with immune properties, such as MHC-I, PTGES, IL6, IL1A, TNFα and IL8 assessed by qPCR. Only TNFα was under expressed in treated cells, while the other markers were either overexpressed or not changed. In no cases MHC-II expression was detected. The antiproliferative effect of preconditioned eAMSC exposed to activated peripheral blood mononuclear cells (PBMC) showed that SP treatment significantly inhibited proliferation of LPS stimulated PBMC. When eAMSC were stimulated with Poly I:C, all the treatments significantly inhibited proliferation of stimulated PBMC (p < 0.05). Direct contact (coculture) between the preconditioned eAMSC and PBMC, induced a shift of significantly more (CD4/CD25/FOXP3)+ T-regulatory PBMC than naïve eAMSC. In the experiments of this research, we investigated the secreted proteomic profile of naïve and preconditioned eAMSC, 42 up-regulated and 40 down-regulated proteins were found in the proteomic assay. Our proteomic data revealed profound changes in the secretory pattern of MSC exposed to different treatments, compared to naïve eAMSC as well as among treatments. In overall, compared to naïve cells, the protein profile of preconditioned cells resembled the mesenchymal-epithelial transition (MET). Here we showed that the combined use of PGE2 and SP provoked in overall the highest expression of anti-inflammatory markers as well as lead to an increased acquisition of a T-regulatory phenotype in preconditioned eAMSC without affecting their “stemness”.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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