Dark Energy with a Little Help from its Friends

We analyse theories that do not have a de Sitter vacuum and cannot lead to slow-roll quintessence, but which nevertheless support a transient era of accelerated cosmological expansion due to interactions between a scalar $\phi$ and either a hidden sector thermal bath, which evolves as Dark Radiation, or an extremely-light component of Dark Matter. We show that simple models can explain the present-day Dark Energy of the Universe consistently with current observations. This is possible both when $\phi$'s potential has a hilltop form and when it has a steep exponential run-away, as might naturally arise from string theory. We also discuss a related theory of multi-field quintessence, in which $\phi$ is coupled to a sector that sources a subdominant component of Dark Energy, which overcomes many of the challenges of slow-roll quintessence.Comment: 30 pages + appendices (two columns), 9 figure

Continuous Synthesis of Zn2Al-CO3 Layered Double Hydroxides for the Adsorption of Reactive Dyes from Water

A novel pilot scale approach to continuous synthesis of layered double hydroxides (LDHs) was used to produce Zn2Al-CO3. The Zn2Al-CO3 was calcined and used in the adsorption of Reactive Black 5 (RB5) and Reactive Orange 16 (RO16) from water. The specific surface area of the LDH was 50.1 m2 g-1, while the surface area of the calcined LDH (MMO) was 57.8 m2 g-1. X-ray diffraction indicated complete breakdown of the LDH at 500 °C for 4 hours, with amorphous Al2O3 or AlOOH alongside ZnO. Reaction variables in the adsorption system; temperature, adsorbent dose, pH, initial concentration and the effect of competing anions were investigated across four temperatures from 10 °C to 40 °C. Maximum adsorption capacity calculated from the Langmuir isotherm was 895 mg g-1 and 589 mg g-1 at 20 °C, for RB5 and RO16, respectively. Intercalation of dye molecules was the main mode of adsorption, as indicated by shifts in (003) reflection from 11.5° to 4.5° and 3.2° for RB5 and RO16 respectively. Adsorption was best modelled by the pseudo 2nd order kinetic model. The intra-particle diffusion model indicated multiple stages of adsorption; surface adsorption occurs initially, followed by, intra-particle diffusion of dye molecules into the interlayer region. Regeneration through calcination resulted in an adsorption equal to 99 ± 2%

Patogenicidade de Entamoeba dispar em cultivo polixênico e monoxênico comparada a uma cepa virulenta de E. histolytica

Two xenic isolates and cloned cultures of Entamoeba dispar were submitted to monoxenization using Crithidia fasciculata as the associated organism. Growth in monoxenic cultivation and ability of xenic and monoxenic trophozoites to destroy VERO cells and produce lesions in hamster livers were compared to those of a virulent E. histolytica. Parental and cloned E. dispar under monoxenic cultivation showed a remarkable lower growth than the monoxenic E. histolytica and were avirulent in both in vivo and in vitro tests. When xenically cultured, trophozoites of E. dispar showed a moderate lytic activity against VERO cells (1.5 to 41.8% of destruction) but caused severe hepatic lesions in hamsters as those caused by the virulent E. histolytica (29 to 100% in prevalence and 0.86 to 4.00 in lesion degree). Although E. dispar has not been associated with invasive disease in men, the ability of xenic trophozoites to produce prominent tissue damage in experimental conditions has indicated that some strains have a considerable pathogenic potential when in presence of bacteria.Dois isolados de Entamoeba dispar em cultivo polixênico e culturas clonadas deles obtidas foram submetidos à monoxenização utilizando Crithidia fasciculata como organismo associado. O crescimento em cultivo monoxênico dos isolados e clones, bem como sua capacidade de destruir células VERO (efeito citopático) e de produzir lesões hepáticas em hamster foram comparados a uma cepa virulenta de E. histolytica. Os trofozoítos de E. dispar em cultivo monoxênico apresentaram um crescimento nitidamente menor que o de E. histolytica e foram avirulentos tanto no teste in vivo quanto in vitro. Entretanto, isolados e clones de E. dispar em cultivo polixênico exibiram uma atividade lítica moderada sobre as células VERO (1,5 to 41,8% de destruição) e causaram lesões hepáticas em hamster (29 a 100% em prevalência e 0,86 a 4,00 no grau de lesão) tão extensas quanto aquelas causadas pela E. histolytica. Embora E. dispar não seja associada à doença invasiva no homem, a ocorrência de lesões teciduais significativas, causadas por trofozoítos em condições experimentais, indica que esta espécie pode apresentar potencial patogênico considerável quando em presença de bactérias intestinais

Coil-Assisted Retrograde Transvenous Obliteration (CARTO) for the Treatment of Portal Hypertensive Variceal Bleeding: Preliminary Results.

ObjectivesTo describe the technical feasibility, safety, and clinical outcomes of coil-assisted retrograde transvenous obliteration (CARTO) in treating portal hypertensive non-esophageal variceal hemorrhage.MethodsFrom October 2012 to December 2013, 20 patients who received CARTO for the treatment of portal hypertensive non-esophageal variceal bleeding were retrospectively evaluated. All 20 patients had at least 6-month follow-up. All patients had detachable coils placed to occlude the efferent shunt and retrograde gelfoam embolization to achieve complete thrombosis/obliteration of varices. Technical success, clinical success, rebleeding, and complications were evaluated at follow-up.ResultsA 100% technical success rate (defined as achieving complete occlusion of efferent shunt with complete thrombosis/obliteration of bleeding varices and/or stopping variceal bleeding) was demonstrated in all 20 patients. Clinical success rate (defined as no variceal rebleeding) was 100%. Follow-up computed tomography after CARTO demonstrated decrease in size with complete thrombosis and disappearance of the varices in all 20 patients. Thirteen out of the 20 had endoscopic confirmation of resolution of varices. Minor post-CARTO complications, including worsening of esophageal varices (not bleeding) and worsening of ascites/hydrothorax, were noted in 5 patients (25%). One patient passed away at 24 days after the CARTO due to systemic and portal venous thrombosis and multi-organ failure. Otherwise, no major complication was noted. No variceal rebleeding was noted in all 20 patients during mean follow-up of 384±154 days.ConclusionsCARTO appears to be a technically feasible and safe alternative to traditional balloon-occluded retrograde transvenous obliteration or transjugular intrahepatic portosystemic shunt, with excellent clinical outcomes in treating portal hypertensive non-esophageal variceal bleeding

Impressões digitais de DNA e RNA através de AP-PCR em Entamoeba histolytica

Differences were detected in the gene expression of strains of E. histolytica using RNA (RAP-PCR) and DNA fingerprinting (RAPD). Analysis of the electrophoretic profiles of the gels revealed some polymorphic markers that could be used in the individual characterization of the strains. The 260 bands generated by using five different primers for RAP-PCR, as well as RAPD, were employed in the construction of dendograms. The dendogram obtained based on the RAPD products permitted the distinction of symptomatic and asymptomatic isolates, as well the correlation between the polymorphism exhibited and the virulence of the strains. The dendogram obtained for the RAP-PCR products did not show a correlation with the virulence of the strains but revealed a high degree of intraspecific transcriptional variability that could be related to other biological features, whether or not these are involved in the pathogenesis of amebiasis.Diferenças na expressão gênica de cepas de E. histolytica foram obtidas pelo "fingerprinting" de RNA (RAP-PCR) e DNA (RAPD). A análise do perfil eletroforético do gel revelou alguns marcadores polimórficos que poderiam ser usados na caracterização individual das cepas. As 260 bandas geradas pela utilização de cinco primers diferentes, tanto no RAP-PCR, quanto no RAPD foram empregadas na construção de dendogramas. O dendograma obtido com os produtos do RAPD permitiu a distinção das cepas isoladas de pacientes sintomáticos e assintomáticos, além de correlacionar o polimorfismo exibido com a virulência das mesmas. O dendograma obtido com os produtos do RAP-PCR não apresentou correlação com a virulência das cepas, mas revelou uma exuberante variabilidade transcricional intra-específica, que pode estar relacionada a outros caracteres biológicos envolvidos, ou não, na patogênese da amebíase

Modelling Emerging Pollutants in Wastewater Treatment: A Case Study using the Pharmaceutical 17??ethinylestradiol

Mathematical modelling can play a key role in understanding as well as quantifying uncertainties surrounding the presence and fate of emerging pollutants in wastewater treatment processes (WWTPs). This paper presents for the first time a simplified emerging pollutant pathway in the WWTP that incorporates two potential pathways to sequestration. It develops de-terministic and stochastic ordinary differential equations to gain insight into the fate and behaviour of a case study pharmaceutical, with particular focus on sorption to the solid phase, as well as the nature of the experimentally measured solid parent compound. Statistical estimation and inferential procedures are developed and via a proof-of-concept examination, the study explores the transformation pathways of the bioactive chemicals (BACs) in the bioreactor, which is the heart of the WWTP. With a focus on the case study pharmaceutical 17??ethinlyestradiol (EE2), the simulation results show good agreement with the EE2 data. In addition, the results suggest that the experimentally measured solid EE2-parent concentration is very similar to the model-based sequestered EE2-parent concentration

Impressões digitais de DNA e RNA através de AP-PCR em Entamoeba histolytica

Differences were detected in the gene expression of strains of E. histolytica using RNA (RAP-PCR) and DNA fingerprinting (RAPD). Analysis of the electrophoretic profiles of the gels revealed some polymorphic markers that could be used in the individual characterization of the strains. The 260 bands generated by using five different primers for RAP-PCR, as well as RAPD, were employed in the construction of dendograms. The dendogram obtained based on the RAPD products permitted the distinction of symptomatic and asymptomatic isolates, as well the correlation between the polymorphism exhibited and the virulence of the strains. The dendogram obtained for the RAP-PCR products did not show a correlation with the virulence of the strains but revealed a high degree of intraspecific transcriptional variability that could be related to other biological features, whether or not these are involved in the pathogenesis of amebiasis.Diferenças na expressão gênica de cepas de E. histolytica foram obtidas pelo "fingerprinting" de RNA (RAP-PCR) e DNA (RAPD). A análise do perfil eletroforético do gel revelou alguns marcadores polimórficos que poderiam ser usados na caracterização individual das cepas. As 260 bandas geradas pela utilização de cinco primers diferentes, tanto no RAP-PCR, quanto no RAPD foram empregadas na construção de dendogramas. O dendograma obtido com os produtos do RAPD permitiu a distinção das cepas isoladas de pacientes sintomáticos e assintomáticos, além de correlacionar o polimorfismo exibido com a virulência das mesmas. O dendograma obtido com os produtos do RAP-PCR não apresentou correlação com a virulência das cepas, mas revelou uma exuberante variabilidade transcricional intra-específica, que pode estar relacionada a outros caracteres biológicos envolvidos, ou não, na patogênese da amebíase

Impressões digitais de DNA e RNA através de AP-PCR em Entamoeba histolytica

Differences were detected in the gene expression of strains of E. histolytica using RNA (RAP-PCR) and DNA fingerprinting (RAPD). Analysis of the electrophoretic profiles of the gels revealed some polymorphic markers that could be used in the individual characterization of the strains. The 260 bands generated by using five different primers for RAP-PCR, as well as RAPD, were employed in the construction of dendograms. The dendogram obtained based on the RAPD products permitted the distinction of symptomatic and asymptomatic isolates, as well the correlation between the polymorphism exhibited and the virulence of the strains. The dendogram obtained for the RAP-PCR products did not show a correlation with the virulence of the strains but revealed a high degree of intraspecific transcriptional variability that could be related to other biological features, whether or not these are involved in the pathogenesis of amebiasis.Diferenças na expressão gênica de cepas de E. histolytica foram obtidas pelo "fingerprinting" de RNA (RAP-PCR) e DNA (RAPD). A análise do perfil eletroforético do gel revelou alguns marcadores polimórficos que poderiam ser usados na caracterização individual das cepas. As 260 bandas geradas pela utilização de cinco primers diferentes, tanto no RAP-PCR, quanto no RAPD foram empregadas na construção de dendogramas. O dendograma obtido com os produtos do RAPD permitiu a distinção das cepas isoladas de pacientes sintomáticos e assintomáticos, além de correlacionar o polimorfismo exibido com a virulência das mesmas. O dendograma obtido com os produtos do RAP-PCR não apresentou correlação com a virulência das cepas, mas revelou uma exuberante variabilidade transcricional intra-específica, que pode estar relacionada a outros caracteres biológicos envolvidos, ou não, na patogênese da amebíase

Impressões digitais de DNA e RNA através de AP-PCR em Entamoeba histolytica

Differences were detected in the gene expression of strains of E. histolytica using RNA (RAP-PCR) and DNA fingerprinting (RAPD). Analysis of the electrophoretic profiles of the gels revealed some polymorphic markers that could be used in the individual characterization of the strains. The 260 bands generated by using five different primers for RAP-PCR, as well as RAPD, were employed in the construction of dendograms. The dendogram obtained based on the RAPD products permitted the distinction of symptomatic and asymptomatic isolates, as well the correlation between the polymorphism exhibited and the virulence of the strains. The dendogram obtained for the RAP-PCR products did not show a correlation with the virulence of the strains but revealed a high degree of intraspecific transcriptional variability that could be related to other biological features, whether or not these are involved in the pathogenesis of amebiasis.Diferenças na expressão gênica de cepas de E. histolytica foram obtidas pelo "fingerprinting" de RNA (RAP-PCR) e DNA (RAPD). A análise do perfil eletroforético do gel revelou alguns marcadores polimórficos que poderiam ser usados na caracterização individual das cepas. As 260 bandas geradas pela utilização de cinco primers diferentes, tanto no RAP-PCR, quanto no RAPD foram empregadas na construção de dendogramas. O dendograma obtido com os produtos do RAPD permitiu a distinção das cepas isoladas de pacientes sintomáticos e assintomáticos, além de correlacionar o polimorfismo exibido com a virulência das mesmas. O dendograma obtido com os produtos do RAP-PCR não apresentou correlação com a virulência das cepas, mas revelou uma exuberante variabilidade transcricional intra-específica, que pode estar relacionada a outros caracteres biológicos envolvidos, ou não, na patogênese da amebíase

The influence of dna repair genes variants

Funding: This research was funded by FCT—Fundação para a Ciência e a Tecnologia (Portuguese Foundation for Science and Technology) through Project UID/BIM/00009/2019—Centre for Toxicogenomics and Human Health.Radioiodine therapy with131I remains the mainstay of standard treatment for well-differentiated thyroid cancer (DTC). Prognosis is good but concern exists that131I-emitted ionizing radiation may induce double-strand breaks in extra-thyroidal tissues, increasing the risk of secondary malignancies. We, therefore, sought to evaluate the induction and 2-year persistence of micronuclei (MN) in lymphocytes from 26131I-treated DTC patients and the potential impact of nine homologous recombination (HR), non-homologous end-joining (NHEJ), and mismatch repair (MMR) polymorphisms on MN levels. MN frequency was determined by the cytokinesis-blocked micronucleus assay while genotyping was performed through pre-designed TaqMan® Assays or conventional PCR-restriction fragment length polymorphism (RFLP). MN levels increased significantly one month after therapy and remained persistently higher than baseline for 2 years. A marked reduction in lymphocyte proliferation capacity was also apparent 2 years after therapy. MLH1 rs1799977 was associated with MN frequency (absolute or net variation) one month after therapy, in two independent groups. Significant associations were also observed for MSH3 rs26279, MSH4 rs5745325, NBN rs1805794, and tumor histotype. Overall, our results suggest that131I therapy may pose a long-term challenge to cells other than thyrocytes and that the individual genetic profile may influence131I sensitivity, hence its risk-benefit ratio. Further studies are warranted to confirm the potential utility of these single nucleotide polymorphisms (SNPs) as radiogenomic biomarkers in the personalization of radioiodine therapy.publishersversionpublishe