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Pneumatic hydrodynamics influence transplastomic protein yields and biological responses during in vitro shoot regeneration of Nicotiana tabacum callus: Implications for bioprocess routes to plant-made biopharmaceuticals
No full textAbstractTransplastomic plants are capable of high-yield production of recombinant biopharmaceutical proteins. Plant tissue culture combines advantages of agricultural cultivation with the bioprocess consistency associated with suspension culture. Overexpression of recombinant proteins through regeneration of transplastomic Nicotiana tabacum shoots from callus tissue in RITA® temporary immersion bioreactors has been previously demonstrated. In this study we investigated the hydrodynamics of periodic pneumatic suspension of liquid medium during temporary immersion culture (4min aeration every 8h), and the impact on biological responses and transplastomic expression of fragment C of tetanus toxin (TetC). Biomass was grown under a range of aeration rates for 3, 20 and 40-day durations. Growth, mitochondrial activity (a viability indicator) and TetC protein yields were correlated against the hydrodynamic parameters, shear rate and energy dissipation rate (perkg of medium). A critical aeration rate of 440mlmin−1 was identified, corresponding to a shear rate of 96.7s−1, pneumatic power input of 8.8mWkg−1 and initial 20-day pneumatic energy dissipation of 127Jkg−1, at which significant reductions in biomass accumulation and mitochondrial activity were observed. There was an exponential decline in TetC yields with increasing aeration rates at 40days, across the entire range of conditions tested. These observations have important implications for the optimisation and scale-up of transplastomic plant tissue culture bioprocesses for biopharmaceutical production
Seroprevalence of sandfly fever virus infection in military personnel on the western border of Iran
No full textSummaryMilitary troops deployed to endemic areas are at risk of contracting sandfly fever, an arthropod-borne viral infection. Although typically a self-limited disease, sandfly fever can cause significant morbidity and loss of function among soldiers. We conducted this study to determine the extent of past SFV infection in a group of healthy Iranian military personnel in Ilam province on the western border of Iran. A total of 201 serum samples were tested by indirect immunofluorescence assay (IFA) to detect four common sandfly fever virus serotypes. Demographic data were also collected. Overall, 37 samples (18.4%) were positive for specific IgG antibodies to sandfly viruses. Sandfly fever Sicilian virus (SFSV) and sandfly fever Naples virus (SFNV) were the most common serotypes. A positive test was inversely related to nativity (P<0.01) but was not associated with age (P=0.163), duration of presence in the border region (P=0.08) or employment status (P=0.179).Our findings indicate that past SFV infection is common among military personnel in the western border region of Iran, a Leishmania-endemic region. Therefore, it should be considered in the differential diagnosis of troops presenting with acute febrile illness in similar settings
Metal source and tectonic setting of iron oxide-copper-gold (IOCG) deposits: Evidence from an in situ Nd isotope study of titanite from Norrbotten, Sweden
No full textAbstractTitanite occurs as a widespread accessory phase in mineralised zones and alteration associated with iron oxide-copper gold (IOCG) and iron oxide-apatite (IOA) deposits of Norrbotten County, Sweden, and is a major host of the REE in these deposits. In situ analyses of SmNd isotope ratios in titanites previously analysed for UPb geochronology and trace element composition confirms previous interpretations of grain scale isotopic heterogeneity. Initial Nd-isotope ratios expressed relative to CHUR range from ~−3 to −8 in IOA deposits, from ~−1 to −9 in IOCG deposits, and from +2 to −4 in the most Cu-rich, deformed IOCG deposits of the Nautanen Deformation zone. Within individual IOA deposits εNd varies relative to CHUR: from −3.1 to −4.0 at Valkommen (Malmberget), from −1.4 to −5.7 in grain cores, and −7.2 to −8.2 in grain rims rim at Gruvberget; and from −3.0 to −6.0 in grain cores and from −5.8 to −7.1 in grain rims at Luossavaara. In IOCG deposits at Rakkurijärvi εNd varies from −6.1. to −7.1, and in deformed IOCG deposits at Nautanen from −1.3 to −2.3. These values are consistent with the derivation of the REE, and potentially economically enriched metals, from the local volcanic sequence, either via granitic melts, or directly by leaching by metasomatic fluids. The most Cu-rich deposits reflect the involvement of more basic protoliths. The age distribution of these deposits suggest IOA deposit formation during the collisional phase of the Svecofennian orogeny (~1.9–1.8Ga), and IOCG mineralisation during this phase and during post-orogenic collapse (~1.8–1.7Ga), whilst model ages indicate the ultimate enrichment of the continental crust in these metals during pre-collisional extensional and subduction-related basic magmatism. These processes underscore the importance of continental cycles both in producing the preserved geological record of orogenic ore deposition, and in the generation of fertile continental crust, from which metals can be mobilised by subsequent events
LCA of emerging technologies: addressing high uncertainty on inputs' variability when performing global sensitivity analysis
No full textAbstractIn the life cycle assessment (LCA) context, global sensitivity analysis (GSA) has been identified by several authors as a relevant practice to enhance the understanding of the model's structure and ensure reliability and credibility of the LCA results. GSA allows establishing a ranking among the input parameters, according to their influence on the variability of the output. Such feature is of high interest in particular when aiming at defining parameterized LCA models.When performing a GSA, the description of the variability of each input parameter may affect the results. This aspect is critical when studying new products or emerging technologies, where data regarding the model inputs are very uncertain and may cause misleading GSA outcomes, such as inappropriate input rankings. A systematic assessment of this sensitivity issue is now proposed.We develop a methodology to analyze the sensitivity of the GSA results (i.e. the stability of the ranking of the inputs) with respect to the description of such inputs of the model (i.e. the definition of their inherent variability). With this research, we aim at enriching the debate on the application of GSA to LCAs affected by high uncertainties.We illustrate its application with a case study, aiming at the elaboration of a simple model expressing the life cycle greenhouse gas emissions of enhanced geothermal systems (EGS) as a function of few key parameters. Our methodology allows identifying the key inputs of the LCA model, taking into account the uncertainty related to their description
Catéter epidural anudado. Complicación poco frecuente. Reporte de 2 casos
No full textResumenIntroducciónLa inserción de un catéter en el espacio epidural es una técnica anestésica que no está exenta de complicaciones. El anudamiento y la retención de un catéter son complicaciones poco frecuentes. Hallazgos clínicos, evaluación diagnóstica e intervenciones: Presentamos dos casos de complicaciones asociadas al catéter epidural. El primero debido a la formación de un nudo espontaneo y el segundo por retención y posterior ruptura. Los dos casos requirieron extracción quirúrgica.ConclusiónPara evitar estas posibles complicaciones no pasar en exceso el catéter y no dejar más de 5 cm del catéter en el espacio epidural. Si un catéter no puede ser fácilmente retirado se pueden intentar extracción de este usando varias maniobras, si estas son infructuosas o si hay dolor o parestesias, se debe ubicar el catéter con imágenes diagnósticas y solicitar apoyo de neurocirugía.AbstractIntroductionInserting a catheter into the epidural space is an anesthetic technique, not exempt from complications. Catheter knotting and retention are rare complications. Clinical findings, diagnostic evaluation and interventions: Two cases of epidural catheterassociated complications are discussed. The first was due to the development of a spontaneous knot and the second due to retention and then rupture; both cases required surgical removal.ConclusionTo prevent these potential complications, refrain frompassing excessive catheter length and do not leave more than 5 cm of catheter into the epidural space. If a catheter cannot be easily removed, try using several maneuvers and if these fail or there is any pain or paresthesia, diagnostic imaging is required to locate the catheter and request neurosurgery support
Photochemistry of nanoporous carbons: Perspectives in energy conversion and environmental remediation
No full textAbstractThe interest in the use of nanoporous carbon materials in applications related to energy conversion and storage, either as catalysts or additives, has grown over recent decades in various disciplines. Since the early studies reporting the benefits of the use of nanoporous carbons as inert supports of semiconductors and as electron acceptors that enhance the splitting of the photogenerated excitons, many researchers have investigated the key role of carbon matrices coupled to all types of photoactive materials. More recently, our group has demonstrated the ability of semiconductor-free nanoporous carbons to convert the absorbed photons into chemical reactions (i.e. oxidation of pollutants, water splitting, reduction of surface groups) opening new opportunities beyond conventional applications in light energy conversion. The aim of this paper is to review the recent progress on the application of nanoporous carbons in photochemistry using varied illumination conditions (UV, simulated solar light) and covering their role as additives to semiconductors as well as their use as photocatalysts in various fields, describing the photochemical quantum yield of nanoporous carbons for different reactions, and discussing the mechanisms postulated for the carbon/light interactions in confined pore spaces
Bioenergetic potential and genetic diversity of elephantgrass via morpho-agronomic and biomass quality traits
No full textAbstractElephantgrass has been a notable option as bioenergy plant. However, for its bioenergetic use, the quantification of genetic diversity based on biomass quality traits has not been commonly reported in the literature. The objective of this study was to quantify the genetic diversity among 100 accessions of the Active Elephantgrass Germplasm Bank (BAGCE), by means of morphological (flowering, height, vigor and stalk diameter), agronomic (total dry biomass) and biomass quality traits (dry matter concentration, cellulose, lignin, hemicellulose, in vitro digestibility, nitrogen, ash, and calorific value), and the ultimate goal was to use the elephantgrass as a bioenergy feedstock. By using mixed model methodology and genetic diversity analyses, it was found genetic variability between elephantgrass accessions, which is the basic premise to start any breeding program. The BAGCE presented greater genetic variability for the biomass quality traits, when compared with morpho-agronomic traits. The accessions were divided into 6 clusters of genetic similarity, with potential for use in second generation ethanol production and direct biomass combustion, besides forage uses. Furthermore, to potentiate elephantgrass as bioenergetic plant, crosses among divergent individuals from distinct clusters were recommended. Thus, the genetic variability of BAGCE can be exploited to produce superior combinations that can maximize second generation ethanol conversion and biomass direct combustion. In addition, these actions can increase the contribution of elephantgrass for a sustainable energetic matrix diversification
Tetracaine – selective electrodes with polymer membranes and their application in pharmaceutical formulation control
No full textAbstractThe construction and electrochemical response characteristics of poly(vinyl chloride) (PVC) membrane electrodes for tetracaine hydrochloride (TCH) are described. The sensing membranes incorporating ion-association complexes of tetracaine cation with phosphotungstic acid (PTA) or phosphomolybdic acid (PMA) or Sodium tetraphenyl borate (NaTPB) as electroactive materials and di-n-butyl phthalate (DBPH) or tri-n-butyl phosphate (TBP) as a plasticizer in PVC matrixes were evaluated. The results obtained show the electrodes based on PTA or PMA as electroactive compounds and DBPH as plasticizer with a fast, stable and near-Nernstian response over a wide concentration range (1×10−5–5×10−2M), with cationic slopes of 55.02 and 52.05mVdecade−1 over a pH range of (2.5–6.5). The electrodes show good discrimination of tetracaine from several inorganic cations and sugars. The electrodes were successfully applied for the determination of tetracaine in pharmaceutical formulations
Tackling the Fallout From Chronic Kidney Disease of Unknown Etiology: Why We Need to Focus on Providing Peritoneal Dialysis in Rural, Low-Resource Settings
No full textGluconacetobacter sp. gel_SEA623-2, bacterial cellulose producing bacterium isolated from citrus fruit juice
No full textAbstractCellulose producing bacterial strain was isolated from citrus fruit juice fungus. The isolated strain was identified as Gluconacetobacter sp. gel_SEA623-2 based on several morphological characteristics, biochemical tests, and 16S rRNA conducted. Culture conditions for bacterial cellulose production by SEA623-2 were screened in static trays. Conditions were extensively optimized by varying the kind of fruit juice, pH, sugar concentration, and temperature for maximum cellulose production. SEA623-2 has a high productive capacity in citrus processing medium, but not in other fruits. The optimal combination of the media constituents for bacterial cellulose production is as follows: 10% citrus juice, 10% sucrose, 1% acetic acid, and 1% ethanol at 30°C, pH 3.5. Bacterial cellulose produced by SEA623-2 has soft physical properties, high tensile strength, and high water retention value. The cellulose produced by the selected bacteria is suitable as a cosmetic and medical material