1,640 research outputs found
Monitoring of hazardous substances at Alcantarilhaâs WTP, Portugal
A monitoring programme of hazardous substances was implemented in Alcantarilhaâs
water treatment plant (Algarve, Portugal) since 2002, in addition to the legally established
monitoring of standard physical, chemical and microbiological parameters. The objective of this
programme was to ensure the drinking water quality regarding the waterborne disease organisms
Cryptosporidium, Giardia, Salmonella, Pseudomonas aeruginosa, enterovirus and cyanobacteria,
and the potentially harmful chemicals aluminium, cyanotoxins, and disinfection by-products (THM)
and their precursors (TOC, DOC, UV254nm, SUVA). Most of these parameters are new and still not
regulated by the Portuguese and the European legislation. Data presented in this study refer to the
period of August 2002 to October 2003. Results show that, despite the seasonal variations of the
raw water quality, concentrations of the hazardous substances in the supplied drinking water were
far below the legal standards and the WHOâs and EPA guideline values, demonstrating the high
removal efficiencies of this treatment plant
OPTEXPLOR â new application for water resources management for private water supply utilities
This article presents the steps made for the development of a new water
management system (WMS) for a private water utility in the south of Portugal, and its main
results. The WMS is composed of a set of models representing the water resources, surface
and groundwater, water quality models, economic models, and water allocation
optimization models. The system was developed at the request of the regional water utility
(Ăguas do Algarve, S.A.), which is responsible for distributing water to the entire Algarve
region (most touristic area in Portugal, with about ten million tourists per year, and a local
population of about four hundred thousand). Results clearly show that independently of the
amount of water available, inter-annual exploration is always the best solution, if possible.
When water scarcity is high, as in consecutive dry years, the water utility will need to call
municipalities to use their systems to complement supply. The level of supply deficit is
higher, in any case, for annual exploration management, and so are exploration costs. These
results clearly show that water resources management needs careful inter-annual planning,
even for a private water supply utility with very limited control over water exploration by
other competing users
Brewers' spent grain as substrates for production of cellulolytic and hemicellulolytic enzymes by different Aspergillus species
Brewers' spent grain (BSG) is the major by-product of the brewing industry, representing around 85% of the
total by-products generated. It is a lignocellulosic material containing about 38% cellulose, 29%
hemicellulose, chiefly arabinoxylans, and 13% lignin. The production of cellulolytic and hemicellulolytic
enzymes using this material as substrate represent an eco-friendly strategy for the lignocellulosic biomass
hydrolysis, generating fermentable sugars that can be converted into high- added value products, such as
bioethanol, lactic acid, xylitol and others. Thus, this work aimed to evaluate the potential of cellulolytic and
hemicellulolytic enzymes production by some Aspergillus species cultivated in BSG. Fungi were grown in
minimum media, pH 6.5, with 1% BSG and inoculum was done with 107spores/mL, cultivated at 30°C, 120
rpm, for 5 days. Every 24 hours 2 mL of the samples were collected. The enzymatic activity was performed
after the incubation of the crude extract with 1% Linear arabinan, Xylan from beechwood, Xyloglucan, Locust
bean gum and CMC, at 50°C for 60 minutes and the reducing sugars were determined using dinitrosalicylic
acid (DNS). Synthetic substrates (2 mM of PNP--L-arabinofuranoside, PNP--D-xylopyranoside, PNP--Dglucopyranoside
and PNP--D-cellobioside) were also used at the same conditions. The extract from A.
niveus showed the best arabinanase (0.284 U/mL) and -glucosidase (0.126 U/mL) activities after 48 and 96
hours of cultivation, respectively. On the other hand, the extract from A. brasiliensis presented the best
activities of -L-arabinofuranosidase (0.129 U/mL), -xylosidase (0.265 U/mL) and xylanase (2.15 U/mL)
when cultivated for 48 hours. After 72 hours, this fungus also showed the best activities for xyloglucanase
(1.06 U/mL), mannanase (0.617 U/mL) and endoglucanase (0.254 U/mL). The extract produced by A. flavus
presented the best cellobiohydrolase activity with 0.113 U/mL after 120 hours of cultivation. It is important to
mention that A. awamori, A. clavatus and A. terreus also showed good levels of different enzymes produced
but they were not the best producers. These data suggest the great potential of different cellulolytic and
hemicellulolytic enzymes production using BSG as substrate, which represents an eco-friendly destination
for the residues and can generate high-added value products with great biotechnological application.Coordenação de Aperfeiçoamento de Pessoal de NĂvel Superior (CAPES)Fundação de Amparo Ă Pesquisa do Estado de SĂŁo Paulo (FAPESP)Institutos Nacionais de CiĂŞncia e Tecnologia (INCT)Fundação para a CiĂŞncia e a Tecnologia (FCT)info:eu-repo/semantics/publishedVersio
Production of an enzymatic cocktail by Aspergillus awamori grown on corn straw with stirred tank bioreactor
Increased agroindustrial activity has led to the accumulation of large amounts of lignocellulosic material
(LCM). LCM is nature's most abundant source of renewable carbon, representing a valuable industrial
substrate with potential for many applications. Thus, the objective of this work was to screen for different
holocellulases and to analyze the production of an Aspergillus awamori enzyme cocktail grown in corn straw
(CS) using a stirred tank bioreactor. Screening was performed with A. clavatus, A. flavus, A. terreus, A.
niveus, A. awamori and A. brasiliensis cultivated in minimal medium (MM), with 1% CS at 30 ÂşC or 37 ÂşC (for
A. niveus), 120 rpm, for 5 days. Xylanase (XYN) and endoglucanase (EG) activities were evaluated by
formation of reducing sugars using dinitrosalicylic acid (DNS). Cellobiohydrolase (CBH), -glucosidase (BGL)
and -xylosidase (BXL) were determined by cleavage of PNP--D-cellobioside, PNP--D-glucopyranoside
and PNP--D- xylopyranoside, respectively. After screening, a pre-inoculum was prepared with the best
enzyme producer using a 500 mL MM flask and incubated at 30 °C, 120 rpm for 48 hours. The increase of
enzyme production was performed in a Benchtop BioFlo 310 bioreactor, with 4.5 L of MM and 1% of CS, and
was then inoculated the best enzyme producer. Cultivation was performed at 30 °C, pH 6.5, 275 rpm, air flow
2 v.v.m., for 5 days. During the screening, all fungi presented EG, CBH, BGL, XYN and BXL activities.
However, A. awamori was chosen to continue the experiments because of its BXL activity which was 12.6
times higher than that produced by A. niveus. At the scale-up stage, XYN production (47.80 U/ mL) increased
4.1-fold compared to flask activity (11.52 U/mL). BXL also showed 1.6-times higher activity, as well as EG,
CBH and BGL, which improved 2.3, 3.3 and 1.2 times their activities, respectively. It was concluded that the
staggering of cocktail production improved the enzymatic activities and that corn straw is an excellent source
of induction. Furthermore, this cocktail has the potential to be applied in the hydrolysis of different LCM due
to the range of holocellulases present.Coordenação de Aperfeiçoamento de Pessoal de NĂvel Superior (CAPES)Fundação de Amparo Ă Pesquisa do Estado de SĂŁo Paulo (FAPESP)Institutos Nacionais de CiĂŞncia e Tecnologia (INCT)Fundação para a CiĂŞncia e a Tecnologia (FCT)info:eu-repo/semantics/publishedVersio
UWISH2 -- The UKIRT Widefield Infrared Survey for H2
We present the goals and preliminary results of an unbiased, near-infrared,
narrow-band imaging survey of the First Galactic Quadrant (10deg<l<65deg ;
-1.3deg<b<+1.3deg). This area includes most of the Giant Molecular Clouds and
massive star forming regions in the northern hemisphere. The survey is centred
on the 1-0S(1) ro-vibrational line of H2, a proven tracer of hot, dense
molecular gas in star-forming regions, around evolved stars, and in supernova
remnants. The observations complement existing and upcoming photometric surveys
(Spitzer-GLIMPSE, UKIDSS-GPS, JCMT-JPS, AKARI, Herschel Hi-GAL, etc.), though
we probe a dynamically active component of star formation not covered by these
broad-band surveys. Our narrow-band survey is currently more than 60% complete.
The median seeing in our images is 0.73arcsec. The images have a 5sigma
detection limit of point sources of K=18mag and the surface brightness limit is
10^-19Wm^-2arcsec^-2 when averaged over our typical seeing. Jets and outflows
from both low and high mass Young Stellar Objects are revealed, as are new
Planetary Nebulae and - via a comparison with earlier K-band observations
acquired as part of the UKIDSS GPS - numerous variable stars. With their
superior spatial resolution, the UWISH2 data also have the potential to reveal
the true nature of many of the Extended Green Objects found in the GLIMPSE
survey.Comment: 14pages, 8figures, 2tables, accepted for publication by MNRAS, a
version with higher resolution figures can be found at
http://astro.kent.ac.uk/~df
"Sustainable Cellulose Nanofibers-Mediated Synthesis of Uniform Spinel Zn-Ferrites Nanocorals for High Performances in Supercapacitors"
Spinel ferrites are versatile, low-cost, and abundant metal oxides with remarkable electronic and magnetic properties, which find several applications. Among them, they have been considered part of the next generation of electrochemical energy storage materials due to their variable oxidation states, low environmental toxicity, and possible synthesis through simple green chemical processing. However, most traditional procedures lead to the formation of poorly controlled materials (in terms of size, shape, composition, and/or crystalline structure). Thus, we report herein a cellulose nanofibers-mediated green procedure to prepare controlled highly porous nanocorals comprised of spinel Zn-ferrites. Then, they presented remarkable applications as electrodes in supercapacitors, which were thoroughly and critically discussed. The spinel Zn-ferrites nanocorals supercapacitor showed a much higher maximum specific capacitance (2031.81 F gâ1 at a current density of 1 A gâ1) than Fe2O3 and ZnO counterparts prepared by a similar approach (189.74 and 24.39 F gâ1 at a current density of 1 A gâ1). Its cyclic stability was also scrutinized via galvanostatic charging/discharging and electrochemical impedance spectroscopy, indicating excellent long-term stability. In addition, we manufactured an asymmetric supercapacitor device, which offered a high energy density value of 18.1 Wh kgâ1 at a power density of 2609.2 W kgâ1 (at 1 A gâ1 in 2.0 mol Lâ1 KOH electrolyte). Based on our findings, we believe that higher performances observed for spinel Zn-ferrites nanocorals could be explained by their unique crystal structure and electronic configuration based on crystal field stabilization energy, which provides an electrostatic repulsion between the d electrons and the p orbitals of the surrounding oxygen anions, creating a level of energy that determines their final supercapacitance then evidenced, which is a very interesting property that could be explored for the production of clean energy storage devices
Subversion of early innate antiviral responses during antibody-dependent enhancement of Dengue virus infection induces severe disease in immunocompetent mice
Dengue is a mosquito-borne disease caused by one of four serotypes of Dengue virus (DENV-1â4). Epidemiologic and observational studies demonstrate that the majority of severe dengue cases, dengue hemorrhagic fever and dengue shock syndrome (DHF/DSS), occurs predominantly in either individuals with cross-reactive immunity following a secondary heterologous infection or in infants with primary DENV infections born from dengue-immune mothers, suggesting that B-cell-mediated and antibody responses impact on disease evolution. We demonstrate here that B cells play a pivotal role in host responses against primary DENV infection in mice. After infection, ÎźMT[superscript â/â] mice showed increased viral loads followed by severe disease manifestation characterized by intense thrombocytopenia, hemoconcentration, cytokine production and massive liver damage that culminated in death. In addition, we show that poly and monoclonal anti-DENV-specific antibodies can sufficiently increase viral replication through a suppression of early innate antiviral responses and enhance disease manifestation, so that a mostly non-lethal illness becomes a fatal disease resembling human DHF/DSS. Finally, treatment with intravenous immunoglobulin containing anti-DENV antibodies confirmed the potential enhancing capacity of subneutralizing antibodies to mediate virus infection and replication and induce severe disease manifestation of DENV-infected mice. Thus, our results show that humoral responses unleashed during DENV infections can exert protective or pathological outcomes and provide insight into the pathogenesis of this important human pathogen
How communication affects prescription decisions in consultations for acute illness in children:a systematic review and meta-ethnography
BACKGROUND: Communication within primary care consultations for children with acute illness can be problematic for parents and clinicians, with potential misunderstandings contributing to overâprescription of antibiotics. This review aimed to synthesise the evidence in relation to communication and decision making in consultations for children with common acute illness. METHODS: A systematic search of MEDLINE, EMBASE, CINAHL, PsycINFO, SSCI, SIGLE, Dissertation Express and NHS economic evaluation databases was conducted. Studies of primary care settings in high income countries which made direct observations of consultations and reported qualitative data were included. Included studies were appraised using the process recommended by the Cochrane Qualitative Methods Group. Credibility was assessed as high for most studies but transferability was usually assessed low or unclear. Data were synthesised using a metaâethnographic approach. RESULTS: Thirtyâfive papers and 2 theses reporting on 13 studies were included, 7 of these focussed on children with respiratory tract infections (RTI) and the remaining 6 included children with any presenting illness. Parent communication focussed on their concerns and information needs, whereas clinician communication focussed on diagnosis and treatment decisions. During information exchanges, parents often sought to justify the need for the consultation, while clinicians frequently used problem minimising language, resulting in parents and clinicians sometimes talking at crossâpurposes. In the context of RTIs, a range of parent communication behaviours were interpreted by clinicians as indicating an expectation for antibiotics; however, most were ambiguous and could also be interpreted as raising concerns or requests for further information. The perceived expectation for antibiotics often changed clinician decision making into clinicianâparent negotiation. CONCLUSIONS: Misunderstandings occurred due to parents and clinicians talking at cross purposes about the âseriousnessâ of the illness and because parentsâ expressions of concern or requests for additional information were sometimes perceived as a challenge to the cliniciansâ diagnosis or treatment decision. This modifiable problem may be an important contribution to the unnecessary and unwanted prescribing of antibiotics. Primary care clinicians should be offered training to understand parent communication primarily as expressions of concern or attempts at understanding and always to check rather than infer parental expectations
A Model of DENV-3 Infection That Recapitulates Severe Disease and Highlights the Importance of IFN-Îł in Host Resistance to Infection
There are few animal models of dengue infection, especially in immunocompetent mice. Here, we describe alterations found in adult immunocompetent mice inoculated with an adapted Dengue virus (DENV-3) strain. Infection of mice with the adapted DENV-3 caused inoculum-dependent lethality that was preceded by several hematological and biochemical changes and increased virus dissemination, features consistent with severe disease manifestation in humans. IFN-Îł expression increased after DENV-3 infection of WT mice and this was preceded by increase in expression of IL-12 and IL-18. In DENV-3-inoculated IFN-Îłâ/â mice, there was enhanced lethality, which was preceded by severe disease manifestation and virus replication. Lack of IFN-Îł production was associated with diminished NO-synthase 2 (NOS2) expression and higher susceptibility of NOS2â/â mice to DENV-3 infection. Therefore, mechanisms of protection to DENV-3 infection rely on IFN-Îł-NOS2-NO-dependent control of viral replication and of disease severity, a pathway showed to be relevant for resistance to DENV infection in other experimental and clinical settings. Thus, the model of DENV-3 infection in immunocompetent mice described here represents a significant advance in animal models of severe dengue disease and may provide an important tool to the elucidation of immunopathogenesis of disease and of protective mechanisms associated with infection
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