22 research outputs found

    Electrochemical evaluation of dsDNA—Liposomes interactions

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    The aim of the present work was to evaluate the interaction between double-stranded DNA (dsDNA) and liposomes by voltammetric methods. The experimental results were analyzed considering the initial studies regarding the oxidation mechanism of dsDNA purine bases by cyclic and differential pulse voltammetry at the glassy carbon electrode (GCE). The interaction between dsDNA and 1,2-Dimyristoyl-sn-glycero-3-phosphocholine (DMPC) was studied in a suspension containing both dsDNA and DMPC liposomes, prepared in pH = 7.0, 0.1 M phosphate buffer and using different incubation time periods. The formation of dsDNA-liposome complex was put in evidence by the decrease of the dsDNA oxidation peaks, dependent upon the incubation time. This behavior was explained considering the electroactive centers of dsDNA, guanosine monophosphate and adenosine monophosphate residues, part of them hidden inside the dsDNA-liposome complex structure and thus being unable to reach the GC electrode and preventing their oxidation. The electrochemical results are relevant for a better physicochemical characterisation of the dsDNA and dsDNA-liposome complex, which can be important for the development of gene therapy vectors

    Vaccination barriers and drivers in Romania: a focused ethnographic study

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    Background: In 2016-18, a large measles outbreak occurred in Romania identified by pockets of sub-optimally vaccinated population groups in the country. The aim of the current study was to gain insight into barriers and drivers from the experience of measles vaccination from the perspectives of caregivers and their providers. Methods: Data were collected by non-participant observation of vaccination consultations and individual interviews with health workers and caregivers in eight Romanian clinics with high or low measles vaccination uptake. Romanian stakeholders were involved in all steps of the study. The findings of this study were discussed during a workshop with key stakeholders. Results: Over 400 h of observation and 161 interviews were conducted. A clear difference was found between clinics with high and low measles vaccination uptake which indicates that being aware of and following recommended practices for both vaccination service delivery and conveying vaccine recommendations to caregivers may have an impact on vaccine uptake. Barriers identified were related to shortcomings in following recommended practices for vaccination consultations by health workers (e.g. correctly assessing contraindications or providing enough information to allow an informed decision). These observations were largely confirmed in interviews with caregivers and revealed significant knowledge gaps. Conclusions: The identification of key barriers provided an opportunity to design specific interventions to improve vaccination service delivery (e.g. mobile vaccination clinics, use of an electronic vaccination registry system for scheduling of appointments) and build capacity among health workers (e.g. guidance and supporting materials and training programmes)

    Potential of microbial functional communities for high-tech critical metals recovery

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    According to European Commission reports published between 2010 - 2013, the development of European economy depends crucially on access to critical raw materials. Following the analysis performed by experts at European level, in 2011 was compiled and published a list of 14 critical raw materials, the so-called EU-14. In 2014 the list was updated with several new elements and one element (tantalum), was withdrawn from the list. The current list, being renamed EU-20, covers 20 critical raw materials including several high tech critical metals. Traditional mine exploitations are concentrated on using the deposits of ore extracted and processed by conventional techniques. The efficiency of metal recovery was variable over time and as a result, a significant amount of metal was discarded, most concentrations exceeding the current minimal permissible threshold. On the other hand, it is necessary the recovery of recyclable waste for reducing the risk of shortage of high tech critical metals. Therefore, it is necessary to develop new technologies for obtaining high tech critical metals, which is applicable to both primary and secondary sources of raw materials. Recovery of high-tech critical metals by processing ore, tailings or mine wastes, and recyclable materials can be successfully done with help of consortia or individual isolates of microorganisms, bacteria or fungi. Microorganisms interact with metals thus altering their physical and chemical condition. Isolation of individual strains and identification of microbial consortia that can be used in the design and development of effective biotechnological processes for the extraction of high tech critical metals is a current challenge of the scientific research in Europe

    Preliminary screening of bacterial isolates from mining wastes

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    Developing innovative biotechnology for obtaining new resources of high tech critical metals is strongly influenced by the need to reduce the potential risk of shortages, to support the development of industry at European level. To set up these new technologies is essential to isolate strains with high potential in bioleaching of ore, tailings and mine wastes and bioaccumulation of high tech critical metals. Microorganisms are capable of mediating metal and mineral bioprecipitation. In this paper are presented preliminary studies performed for the isolation of strains existing in mining residues containing high tech critical metals. Were used samples collected from various depths in an area of mining wastes containing high tech critical metals. The samples were fine grounded and the powder was washed with sterile saline water. Exact quantities of samples were dispersed in sterile saline water, shaken for a period of 60 minutes, diluted and plated in triplicate on selective agar. After several steps were isolated 3 strains of gram negative bacteria

    SOCIAL, PSYCHOLOGICAL, AND ACADEMIC IMPACTS OF NATIONAL LOCKDOWN AMONG GRADUATE STUDENTS OF WESTERN PHILIPPINES UNIVERSITY

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    The national lockdown due to the global pandemic of the COVID-19 has affected all people in the world. The education sector particularly higher education has been impacted by the global crisis brought about by the COVID-19 socially, psychologically, and academically. According to Xiang et al., (2020), the COVID-19 is the greatest public emergency the world has experienced of global proportion. The study used a descriptive survey design involving graduate students of Western Philippines University, Rio Tuba, Palawan. A questionnaire was used to gather the needed data which was sent electronically through the email of the respondents. Frequency, percentage, and mean were used to analyze and interpret the data gathered from the respondents. Significant findings of the study revealed that the respondents experienced various social, psychological, and academic impacts due to the global effect of the COVID-19. Likewise, the study recommends that teaching personnel may use relevant teaching strategies to continue education despite the pandemic. This include, online modalities such as synchronous and asynchronous teaching and learning. For the students who have problems in connectivity, modular learning and long-distance consultation are strongly recommended. More importantly, the COVID-19 pandemic is an opportunity to design and develop teaching and learning pedagogies relevant to the new education normal

    Spatial Distribution of Some Heavy Metals in Sediments in the River Hadejia Catchment, Nigeria

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    Heavy metals concentration levels were determined using Instrumental Neutron Activation Analysis (INAA) technique which is possible using Nigeria Research Reactor-1 (NIRR) which is a Miniature Neutron Source Reactor (MNSR). The selection of sediment sample is because, overtime, the chemical elements precipitate on the sediment bed; therefore the sediment sample will indicate the true nature of the chemical elements present in the river system. The sediment samples were collected using stratified random sampling technique based on change in land use activity. Samples were collected during dry and wet seasons and analyzed in the laboratory. The results obtained show the presence of chemical contaminants Chromium (Cr), Zinc (Zn), and Europium (Eu) in concentrations above the permissible limits in the Hadejia river system. For example, Chromium (Cr) has mean concentration of 432.86 mg/l as against the permissible limit for both WHO, (2011) and NSDWQ, (2007) of 0.05mg/l. Anthropogenic and natural geology of the area are the key determinants of the presence of these chemical elements in the area. It is recommended among others that there is need for routing the actual sources of these contaminants in our river catchment areas

    Spatial Distribution of Some Heavy Metals in Sediments from the River Hadejia Catchment, Nigeria

    No full text
    Heavy metals concentration levels was determined using Instrumental Nitrogen Activation Analysis (INAA) is possible using Nigeria Research Reactor-1 (NIRR) which is a Miniature Neutron Source Reactor (MNSR). It is specifically used for the Neutron Activation Analysis (NAA) technique. The selection of sediment sample is because, overtime, the chemical elements precipitate on the sediment bed; therefore the sediment sample will indicate the true nature of the chemical elements present in the river system. River Hadejia is a perennial river, though the dry season flow is from the upstream regulated flow from the Tiga and Bagauda dams. The sediment samples were collected using stratified random sampling technique based on change in land use activity. Samples were collected during dry and wet seasons and analyzed in the laboratory. The results obtained show the presence of chemical contaminants Chromium (Cr), Zinc (Zn), and Europium (Eu) in concentrations above the permissible limits in the Hadejia river system. For example, Chromium (Cr) has mean concentration of 432.86 mg/l as against the permissible limit for both WHO, (2011) and NSDWQ, (2007) of 0.05mg/l. Anthropogenic and natural geology of the area are the key determinants of the presence of these chemical elements in the area. It is recommended among others that there is need for routing the actual sources of these contaminants in our river catchment areas
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