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Efficient separation of carbon dioxide and methane in high-pressure and wet gas mixtures using Zr-MOF-808
The capture and separation of carbon dioxide (CO2) has been the focus of a plethora of research in order to mitigate its emissions and contribute to global development. Given that CO2 is commonly found in natural gas streams, there have been efforts to seek more efficient materials to separate gaseous mixtures such as CO2/CH4. However, there are only a few reports regarding adsorption processes within pressurized systems. In the offshore scenario, natural gas streams still exhibit high moisture content, necessitating a greater understanding of processes in moist systems. In this article, a metal-organic framework synthesis based on zirconium (MOF-808) was carried out through a conventional solvothermal method and autoclave for the adsorption of CO2 and CH4 under different temperatures (45–65 °C) and pressures up to 100 bar. Furthermore, the adsorption of humid CO2 was evaluated using thermal analyses. The MOF-808 synthesized in autoclave showed a high surface area (1502 m2/g), a high capacity for CO2 adsorption at 50 bar and 45 °C and had a low selectivity to capture CH4 molecules. It also exhibited a fine stability after five cycles of CO2 adsorption and desorption at 50 bar and 45 °C − as confirmed by structural post-adsorption analyses while maintaining its adsorption capacity and crystallinity. Furthermore, it can be observed that the adsorption capacity increased in a humid environment, and that the adsorbent remained stable after adsorption cycles in the presence of moisture. Finally, it was possible to confirm the occurrence of physisorption processes through nuclear magnetic resonance (NMR) analyses, thus validating the choice of mild temperatures for regeneration and contributing to the reduction of energy consumption in processing plants
Zinc associated nanomaterials and their intervention in emerging respiratory viruses:Journey to the field of biomedicine and biomaterials
Respiratory viruses represent a severe public health risk worldwide, and the research contribution to tackle the current pandemic caused by the SARS-CoV-2 is one of the main targets among the scientific community. In this regard, experts from different fields have gathered to confront this catastrophic pandemic. This review illustrates how nanotechnology intervention could be valuable in solving this difficult situation, and the state of the art of Zn-based nanostructures are discussed in detail. For virus detection, learning from the experience of other respiratory viruses such as influenza, the potential use of Zn nanomaterials as suitable sensing platforms to recognize the S1 spike protein in SARS-CoV-2 are shown. Furthermore, a discussion about the antiviral mechanisms reported for ZnO nanostructures is included, which can help develop surface disinfectants and protective coatings. At the same time, the properties of Zn-based materials as supplements for reducing viral activity and the recovery of infected patients are illustrated. Within the scope of noble adjuvants to improve the immune response, the ZnO NPs properties as immunomodulators are explained, and potential prototypes of nanoengineered particles with metallic cations (like Zn(2+)) are suggested. Therefore, using Zn-associated nanomaterials from detection to disinfection, supplementation, and immunomodulation opens a wide area of opportunities to combat these emerging respiratory viruses. Finally, the attractive properties of these nanomaterials can be extrapolated to new clinical challenges
Zinc associated nanomaterials and their intervention in emerging respiratory viruses: Journey to the field of biomedicine and biomaterials.
Respiratory viruses represent a severe public health risk worldwide, and the research contribution to tackle the current pandemic caused by the SARS-CoV-2 is one of the main targets among the scientific community. In this regard, experts from different fields have gathered to confront this catastrophic pandemic. This review illustrates how nanotechnology intervention could be valuable in solving this difficult situation, and the state of the art of Zn-based nanostructures are discussed in detail. For virus detection, learning from the experience of other respiratory viruses such as influenza, the potential use of Zn nanomaterials as suitable sensing platforms to recognize the S1 spike protein in SARS-CoV-2 are shown. Furthermore, a discussion about the antiviral mechanisms reported for ZnO nanostructures is included, which can help develop surface disinfectants and protective coatings. At the same time, the properties of Zn-based materials as supplements for reducing viral activity and the recovery of infected patients are illustrated. Within the scope of noble adjuvants to improve the immune response, the ZnO NPs properties as immunomodulators are explained, and potential prototypes of nanoengineered particles with metallic cations (like Zn2+) are suggested. Therefore, using Zn-associated nanomaterials from detection to disinfection, supplementation, and immunomodulation opens a wide area of opportunities to combat these emerging respiratory viruses. Finally, the attractive properties of these nanomaterials can be extrapolated to new clinical challenges
The Echinococcus canadensis (G7) genome: A key knowledge of parasitic platyhelminth human diseases
Background: The parasite Echinococcus canadensis (G7) (phylum Platyhelminthes, class Cestoda) is one of the causative agents of echinococcosis. Echinococcosis is a worldwide chronic zoonosis affecting humans as well as domestic and wild mammals, which has been reported as a prioritized neglected disease by the World Health Organisation. No genomic data, comparative genomic analyses or efficient therapeutic and diagnostic tools are available for this severe disease. The information presented in this study will help to understand the peculiar biological characters and to design species-specific control tools. Results: We sequenced, assembled and annotated the 115-Mb genome of E. canadensis (G7). Comparative genomic analyses using whole genome data of three Echinococcus species not only confirmed the status of E. canadensis (G7) as a separate species but also demonstrated a high nucleotide sequences divergence in relation to E. granulosus (G1). The E. canadensis (G7) genome contains 11,449 genes with a core set of 881 orthologs shared among five cestode species. Comparative genomics revealed that there are more single nucleotide polymorphisms (SNPs) between E. canadensis (G7) and E. granulosus (G1) than between E. canadensis (G7) and E. multilocularis. This result was unexpected since E. canadensis (G7) and E. granulosus (G1) were considered to belong to the species complex E. granulosus sensu lato. We described SNPs in known drug targets and metabolism genes in the E. canadensis (G7) genome. Regarding gene regulation, we analysed three particular features: CpG island distribution along the three Echinococcus genomes, DNA methylation system and small RNA pathway. The results suggest the occurrence of yet unknown gene regulation mechanisms in Echinococcus. Conclusions: This is the first work that addresses Echinococcus comparative genomics. The resources presented here will promote the study of mechanisms of parasite development as well as new tools for drug discovery. The availability of a high-quality genome assembly is critical for fully exploring the biology of a pathogenic organism. The E. canadensis (G7) genome presented in this study provides a unique opportunity to address the genetic diversity among the genus Echinococcus and its particular developmental features. At present, there is no unequivocal taxonomic classification of Echinococcus species; however, the genome-wide SNPs analysis performed here revealed the phylogenetic distance among these three Echinococcus species. Additional cestode genomes need to be sequenced to be able to resolve their phylogeny.Fil: Maldonado, Lucas Luciano. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; ArgentinaFil: Assis, Juliana. Fundación Oswaldo Cruz; BrasilFil: Gomes Araújo, Flávio M.. Fundación Oswaldo Cruz; BrasilFil: Salim, Anna C. M.. Fundación Oswaldo Cruz; BrasilFil: Macchiaroli, Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; ArgentinaFil: Cucher, Marcela Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; ArgentinaFil: Camicia, Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; ArgentinaFil: Fox, Adolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; ArgentinaFil: Rosenzvit, Mara Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; ArgentinaFil: Oliveira, Guilherme. Instituto Tecnológico Vale; Brasil. Fundación Oswaldo Cruz; BrasilFil: Kamenetzky, Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; Argentin
The cause of urinary symptoms among Human T Lymphotropic Virus Type I (HLTV-I) infected patients: a cross sectional study
BACKGROUND: HTLV-I infected patients often complain of urinary symptomatology. Epidemiological studies have suggested that these individuals have a higher prevalence and incidence of urinary tract infection (UTI) than seronegative controls. However, the diagnosis of UTI in these studies relied only on patient information and did not require confirmation by urine culture. The purpose of this study was to investigate the role of urinary tract infection (UTI) as the cause of urinary symptoms in HTLV-I infected patients. METHODS: In this cross sectional study we interviewed, and cultured urine from, 157 HTLV-I seropositive individuals followed regularly at a specialized clinic. All patients were evaluated by a neurologist and classified according to the Expanded Disability Status Scale (EDSS). Urodynamic studies were performed at the discretion of the treating physician. RESULTS: Sixty-four patients complained of at least one active urinary symptom but UTI was confirmed by a positive urine culture in only 12 of these patients (19%); the majority of symptomatic patients (81%) had negative urine cultures. To investigate the mechanism behind the urinary complaints in symptomatic individuals with negative urine cultures, we reviewed the results of urodynamic studies performed in 21 of these patients. Most of them (90.5%) had abnormal findings. The predominant abnormalities were detrusor sphincter hyperreflexia and dyssynergia, findings consistent with HTLV-I-induced neurogenic bladder. On a multivariate logistic regression, an abnormal EDSS score was the strongest predictor of urinary symptomatology (OR 9.87, 95% CI 3.465 to 28.116, P < 0.0001). CONCLUSION: Urinary symptomatology suggestive of UTI is highly prevalent among HTLV-I seropositive individuals but true UTI is responsible for the minority of cases. We posit that the main cause of urinary symptoms in this population is neurogenic bladder. Our data imply that HLTV-I infected patients with urinary symptomatology should not be empirically treated for UTI but rather undergo urine culture; if a UTI is excluded, further investigation with urodynamic studies should be considered
Tin Dioxide-Based Photoanodes Integrated Into the Dye Sensitized Solar Cells Structure
This academic article investigates the performance of dye-sensitized solar cells (DSSCs), which are affected by various defects like charge recombination, high impedance, and low power conversion efficiency due to complex physicochemical phenomena. The study explores different materials and processes to enhance DSSC performance, with a focus on photoanode development. Tin dioxide, tin chloride II dihydrate, copper oxide, boric acid, and sodium phosphate are utilized to fabricate the photoanodes. A thermal treatment at 450°C for 30 minutes precedes dye assembly on the photoanode surface. Results show that the tin chloride II dihydrate-modified photoanode outperforms others, achieving higher open-circuit voltage (0.50V), current density (9.58 mAcm-2), fill factor (0.37), and power conversion efficiency (1.77%). The study suggests that tin salt particles positively impact voltage, current, electron transport, and charge separation, enhancing overall cell performance. Charge recombination significantly affects power conversion efficiency and impedance, but accurately quantifying it remains challenging. Lower recombination levels favor efficiency, while higher levels reduce it
Aves del Parque Nacional Natural Chingaza y zona de amortiguación, Cordillera Oriental de Colombia
We describe the bird species composition in the Chingaza National Park and its buffer zone, based on a revision of 10 published studies, recent fieldwork between 2008-2017, and the Colombia Bio expedition on 2018. We report 531 species for the Chingaza National Park and its buffer zone, grouped in 339 genera and 57 families. Six species are endemic to Colombia, 14 are near-endemic, 1 is critically endangered, 6 are endangered, 4 are vulnerable, 3 are near-threatened and 37 are migratory. This list includes 149 species more than those comprised in previous information from published datasets and ornithological collections. Additionally, we generated genetic barcodes, based sequences of the mtDNA gene COI, for 74 species, and present the first genetic record from Colombia in Barcode of Life Datasystems (BOLD) for Dysithamnus leucostictus, Chamaeza turdina, Rupicola peruvianus, Atlapetes semirufus, Euphonia mesochrysa and Chlorospingus flavopectus olsoni. This list is a tool to promote the study and conservation of birds in this area of the Colombian Eastern Cordillera.Describimos la composición de especies de aves del Parque Nacional Natural (PNN) Chingaza y su zona de amortiguación, a partir de la revisión de 10 estudios ornitológicos, trabajo de campo entre 2008–2017 y la expedición Colombia Bio en 2018. Reportamos para el PNN Chingaza y su zona de amortiguación un total de 531 especies, agrupadas en 339 géneros y 57 familias. Seis especies presentes en el parque son endémicas de Colombia, 14 casi endémicas, 1 en peligro crítico, 6 en peligro, 4 vulnerables, 3 casi amenazadas y 37 migratorias. Esta lista incluye 149 especies adicionales a la información previamente conocida por datos publicados y colecciones ornitológicas. Adicionalmente, generamos códigos de barras genéticos, con base en secuencias del gen mitocondrial COI, para 74 especies y presentamos los primeros registros genéticos de Colombia en la plataforma para códigos de barra genéticos Barcode of Life Datasystems (BOLD) para Dysithamnus leucostictus, Chamaeza turdina, Rupicola peruvianus, Atlapetes semirufus, Euphonia mesochrysa y Chlorospingus flavopectus olsoni. El presente listado es una herramienta para incentivar el estudio y conservación de las aves en este sector de la Cordillera Oriental colombiana
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