Polymer coated vermiculite-iron composites: Novel floatable magnetic adsorbents for water spilled contaminants

Magnetic adsorbents based on vermiculite-iron have been prepared and characterized by magnetic measurements, BET surface area, Mössbauer spectroscopy, powder X-ray diffraction, scanning electron microscopy, thermogravimetric and differential scanning calorimetric analyses. These magnetic materials show two important features for the remediation of contaminated sites: (i) they float on water and can be used to adsorb/ absorb spilled oils and (ii) after adsorption they can be easily removed from the medium by a simple magnetic separation procedure. These magnetic materials have been coated/hydrophobized with polymers such as epoxy resin and polystyrene improving their oil remotion capacity, floatability and the chemical and mechanical resistance.Fil: Machado, L. C. R.. Universidade Federal de Minas Gerais; BrasilFil: Lima, F. W. J.. Universidade Federal de Minas Gerais; BrasilFil: Paniago, R.. Universidade Federal de Minas Gerais; BrasilFil: Ardisson, J. D.. Universidade Federal de Minas Gerais; BrasilFil: Sapag, Manuel Karim. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Física Aplicada "Dr. Jorge Andrés Zgrablich". Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Instituto de Física Aplicada "Dr. Jorge Andrés Zgrablich"; ArgentinaFil: Lago, Rochel Montero. Universidade Federal de Minas Gerais; Brasi

The endoxylanases from family 11: Computer analysis of protein sequences reveals important structural and phylogenetic relationships

Indexación: Scopus.Eighty-two amino acid sequences of the catalytic domains of mature endoxylanases belonging to family 11 have been aligned using the programs MATCHBOX and CLUSTAL. The sequences range in length from 175 to 233 residues. The two glutamates acting as catalytic residues are conserved in all sequences. A very good correlation is found between the presence (at position 100) of an asparagine in the so-called 'alkaline' xylanases, or an aspartic acid in those with a more acidic pH optimum. Four boxes defining segments of highest similarity were detected; they correspond to regions of defined secondary structure: B5, B6, B8 and the carboxyl end of the alpha helix, respectively. Cysteine residues are not common in these sequences (0.7% of all residues), and disulfide bridges are not important in explaining the stability of several thermophilic xylanases. The alignment allows the classification of the enzymes in groups according to sequence similarity. Fungal and bacterial enzymes were found to form mostly separate clusters of higher similarity.https://www.sciencedirect.com/science/article/pii/S0168165602000020?via%3Dihu

Improvement in the Adsorption of Anionic and Cationic Dyes From Aqueous Solutions: A Comparative Study Using Aluminium Pillared Clays and Activated Carbon

The aim of this work was to evaluate the adsorption properties of anionic dye Reactive Black 5 (RB5) and cationic dye Methylene Blue (MB) from salted aqueous solution using natural clay, aluminum pillared clay (Al-PILC), and activated carbon. The textural properties of the materials were obtained by N2 adsorption at 77 K and the structural properties of natural and pillared clays were determined by X-ray diffraction. The effect of pH, contact time, initial concentration of dye, and influence of the addition of NaCl were evaluated by batch adsorption. Adsorption isotherms of Al-PILC, in different salt concentration were compared with natural clay and activated carbon. The adsorption isotherms were well fitted by the Langmuir and Langmuir-Freundlich models. The process of pillaring only improved the adsorption of the anionic dye RB5. Depending on the system adsorbent/adsorbate analyzed, the salt concentration can either help or hinder dye adsorption. We found that a special morphology formed during the process of pillaring greatly increased adsorption of the MB cationic dye in the range of high salt concentrations. This unexpected result may help in developing new pillarization strategies to treat effluents with high salt content.Fil: Aguiar, J. E.. Universidade Federal do Ceará. Centro de Tecnologia. Departamento de Engenharia Química. Grupo de Pesquisa em Separações por Adsorção; BrasilFil: Bezerra, B. T. C.. Universidade Federal do Ceará. Centro de Tecnologia. Departamento de Engenharia Química. Grupo de Pesquisa em Separações por Adsorção; BrasilFil: Siqueira, A. C. A.. Universidade Federal do Ceará. Centro de Tecnologia. Departamento de Engenharia Química. Grupo de Pesquisa em Separações por Adsorção; BrasilFil: Barrera Diaz, Deicy Amparo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Luis. Instituto de Física Aplicada; ArgentinaFil: Sapag, Manuel Karim. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Luis. Instituto de Física Aplicada; ArgentinaFil: Azevedo, D. C. S.. Universidade Federal do Ceará. Centro de Tecnologia. Departamento de Engenharia Química. Grupo de Pesquisa em Separações por Adsorção; BrasilFil: Lucena, S. M. P.. Universidade Federal do Ceará. Centro de Tecnologia. Departamento de Engenharia Química. Grupo de Pesquisa em Separações por Adsorção; BrasilFil: Silva Jr., I. J.. Universidade Federal do Ceará. Centro de Tecnologia. Departamento de Engenharia Química. Grupo de Pesquisa em Separações por Adsorção; Brasi

Kaolinite-based zeolites synthesis and their application in CO2 capture processes

In light of the urgent need of reducing the atmospheric CO2 emissions, the use of low-cost adsorbents, that exhibit a high affinity and CO2 adsorption capacity, is a promising method from the economic and environmental point of view to separate CO2 from the flue gas emitted from large sources of emissions like power-fueled plants. Clay minerals are low-cost raw materials with high availability all over planet and great versatility in the fields of adsorption and catalysis processes. The present study pretends to elucidate the link between the reaction conditions during the synthesis of the zeolite from kaolinite and its CO2 adsorption capacity. For that purpose, the type A zeolite was synthesized via hydrothermal process in alkaline solution using metakaolinite as a starting material. The metakaolinite was obtained by calcination of kaolinite at 600 degrees C and some parameters such as temperature and synthesis time were modified to optimize the synthesis aiming for a high CO2 adsorption capacity adsorbent. Synthesized materials were characterized by X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), N-2 adsorption-desorption at -196 degrees C and CO2 adsorption at 0 degrees C (up to 10 bars) isotherms and Nuclear Magnetic Resonance of solids (NMR). In addition, the adsorption capacity of CO2 was evaluated by means of CO2 adsorption-desorption isotherms at 25 degrees C up to atmospheric pressure. The obtained results indicated that synthesized zeolite 4A can be successfully prepared from natural kaolinite (via metakaolinization) at 100 degrees C for 48 h under alkaline conditions, showing chemical and physical properties similar to that of the commercial 4A zeolite

Improving Prevention of Mother-to-Child Transmission of HIV Care and Related Services in Eastern Rwanda

Younsook Lim and colleagues describe the Rwanda Learning Collaborative on Child Health, which aimed to improve and extend the impact of prevention of mother-to-child transmission of HIV/AIDS

Tracking health system performance in times of crisis using routine health data: lessons learned from a multicountry consortium

COVID-19 has prompted the use of readily available administrative data to track health system performance in times of crisis and to monitor disruptions in essential healthcare services. In this commentary we describe our experience working with these data and lessons learned across countries. Since April 2020, the Quality Evidence for Health System Transformation (QuEST) network has used administrative data and routine health information systems (RHIS) to assess health system performance during COVID-19 in Chile, Ethiopia, Ghana, Haiti, Lao People's Democratic Republic, Mexico, Nepal, South Africa, Republic of Korea and Thailand. We compiled a large set of indicators related to common health conditions for the purpose of multicountry comparisons. The study compiled 73 indicators. A total of 43% of the indicators compiled pertained to reproductive, maternal, newborn and child health (RMNCH). Only 12% of the indicators were related to hypertension, diabetes or cancer care. We also found few indicators related to mental health services and outcomes within these data systems. Moreover, 72% of the indicators compiled were related to volume of services delivered, 18% to health outcomes and only 10% to the quality of processes of care. While several datasets were complete or near-complete censuses of all health facilities in the country, others excluded some facility types or population groups. In some countries, RHIS did not capture services delivered through non-visit or nonconventional care during COVID-19, such as telemedicine. We propose the following recommendations to improve the analysis of administrative and RHIS data to track health system performance in times of crisis: ensure the scope of health conditions covered is aligned with the burden of disease, increase the number of indicators related to quality of care and health outcomes; incorporate data on nonconventional care such as telehealth; continue improving data quality and expand reporting from private sector facilities; move towards collecting patient-level data through electronic health records to facilitate quality-of-care assessment and equity analyses; implement more resilient and standardized health information technologies; reduce delays and loosen restrictions for researchers to access the data; complement routine data with patient-reported data; and employ mixed methods to better understand the underlying causes of service disruptions

Stigma in health facilities: Why it matters and how we can change it

Stigma in health facilities undermines diagnosis, treatment, and successful health outcomes. Addressing stigma is fundamental to delivering quality healthcare and achieving optimal health. This correspondence article seeks to assess how developments over the past 5 years have contributed to the state of programmatic knowledge - both approaches and methods - regarding interventions to reduce stigma in health facilities, and explores the potential to concurrently address multiple health condition stigmas. It is supported by findings from a systematic review of published articles indexed in PubMed, Psychinfo and Web of Science, and in the United States Agency for International Development's Development Experience Clearinghouse, which was conducted in February 2018 and restricted to the past 5 years. Forty-two studies met inclusion criteria and provided insight on interventions to reduce HIV, mental illness, or substance abuse stigma. Multiple common approaches to address stigma in health facilities emerged, which were implemented in a variety of ways. The literature search identified key gaps including a dearth of stigma reduction interventions in health facilities that focus on tuberculosis, diabetes, leprosy, or cancer; target multiple cadres of staff or multiple ecological levels; leverage interactive technology; or address stigma experienced by health workers. Preliminary results from ongoing innovative responses to these gaps are also described. The current evidence base of stigma reduction in health facilities provides a solid foundation to develop and implement interventions. However, gaps exist and merit further work. Future investment in health facility stigma reduction should prioritize the involvement of clients living with the stigmatized condition or behavior and health workers living with stigmatized conditions and should address both individual and structural level stigma