270 research outputs found
COMPUTATIONAL MODELLING OF CONTAMINANT TRANSPORT UNDER NONLINEAR BIODEGRADATION AND PHYSICAL SORPTION PROCESSES IN A SATURATED POROUS MEDIUM
Abstract The aim of this work is to develop a computational modelling for a multiple species contaminant transport under nonlinear biodegradation and physical sorption processes in a saturated porous medium, which characterizes a scenario of subsurface contamination by organic contaminants. Sorption in nonlinear equilibrium and non-equilibrium conditions are incorporated upon the model setting as Freundlich type. Moreover, aerobic biodegradation is modelled through the multiplicative Monod kinetic. Mathematically, the problem is given by a nonlinear advection-diffusion-reaction partial differential system coupled by the reaction terms, associated with the biodegradation process. A new operator-splitting approach is proposed for treating in a sequential fashion the convectivediffusive and reactive terms. A predictor-multi corrector algorithm with Newton-Raphson and stabilized finite element (SUPG) methods are used in the time and spatial discretizations, respectively. Numerical results illustrate the good applicability and the effectiveness of the present approach, corroborating the well-known observation that to better predict contamination scenarios the nonlinear physical and biological processes should be inserted in the model
Functional hybrid nanoemulsions for sumatriptan intranasal delivery
In recent years, advanced nanohybrid materials processed as pharmaceuticals have proved to be very advantageous. Triptans, such as the commercially available intranasal sumatriptan (SMT), are drugs employed in the treatment of painful migraine symptoms. However, SMT effectiveness by the intranasal route is limited by its high hydrophilicity and poor mucoadhesion. Therefore, we designed hybrid nanoemulsions (NE) composed of copaiba oil as the organic component plus biopolymers (xanthan, pectin, alginate) solubilized in the continuous aqueous phase, aiming at the intranasal release of SMT (2% w/v). Firstly, drug-biopolymer complexes were optimized in order to decrease the hydrophilicity of SMT. The resultant complexes were further encapsulated in copaiba oil-based nanoparticles, forming NE formulations. Characterization by FTIR-ATR, DSC, and TEM techniques exposed details of the molecular arrangement of the hybrid systems. Long-term stability of the hybrid NE at 25°C was confirmed over a year, regarding size (~ 120 nm), polydispersity (~ 0.2), zeta potential (~ −25 mV), and nanoparticle concentration (~ 2.1014 particles/mL). SMT encapsulation efficiency in the formulations ranged between 41–69%, extending the in vitro release time of SMT from 5 h (free drug) to more than 24 h. The alginate-based NE was selected as the most desirable system and its in vivo nanotoxicity was evaluated in a zebrafish model. Hybrid NE treatment did not affect spontaneous movement or induce morphological changes in zebrafish larvae, and there was no evidence of mortality or cardiotoxicity after 48 h of treatment. With these results, we propose alginate-based nanoemulsions as a potential treatment for migraine pain.Fil: Ribeiro, Lígia N. M.. Universidade Estadual de Campinas; BrasilFil: Rodrigues da Silva, Gustavo H.. Universidade Estadual de Campinas; BrasilFil: Couto, Verônica M.. Universidade Estadual de Campinas; BrasilFil: Castro, Simone R.. Universidade Estadual de Campinas; BrasilFil: Breitkreitz, Márcia C.. Universidade Estadual de Campinas; BrasilFil: Martinez, Carolina Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; Argentina. Universidad Nacional de Quilmes; ArgentinaFil: Igartúa, Daniela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Quilmes; ArgentinaFil: Prieto, Maria Jimena. Universidad Nacional de Quilmes; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; ArgentinaFil: de Paula, Eneida. Universidade Estadual de Campinas; Brasi
Hemoglobinopatias no Distrito Federal, Brasil
Em uma amostra de 3137 pessoas, residentes no Distrito Federal, foram detectadas as seguintes hemoglobinas: em 3009(95,92%) HbAA; em 91 (2,90%) HbAS; em 20(0,64%) HbAC; em 8 (0,26%) talassemia beta minor; em 5(0,16%) HbAJ alfa; em 3 (0,09%) HbAM e em 1 (0,03%) talassemia major associada com HbAS. A HbAS têm as seguintes freqüências, quanto ao grupo racial: branco - 1,84%; mulato claro 2,55%; mulato médio-3,68%; mulato escuro - 6,80%; negro -10,43% e mestiço de índio -3,85%.The hemoglobins of 3137 persons from the Federal District, Brazil was studied. The identified types of hemoglobins were: HbAA (3009 - 95,92%); HbAS (91 - 2,90%); HbAC (20 - 0,64%) beta thalassemia minor (8 - 0,26%); HbAJ alpha (5 - 0,16%); HbAM (3 - 0,09%) and beta thalassemia major/HbS (1 - 0,03%). The frequencies of sickle cell trait (HbAS) of each racial class were: white (1,84%); light mulatto (2,55%); medium mulatto (3,68%); dark mulatto(6,80%), negro (10,43%)and indian mestizo (3,85%)
Decrease in APP and CP mRNA expression in Alzheimer’s disease patients suggests impairment of cellular iron export in this dementia
Recentemente tem-se assistido a um acumular de evidência sugerindo a
implicação de uma desregulação do metabolismo do ferro (Fe) na fisiopatologia
da doença de Alzheimer (DA). Neste trabalho, pretendemos esclarecer
melhor os mecanismos moleculares subjacentes à homeostasia deste
metal na DA, particularmente ao nível do efluxo celular. Assim, mediu-se
em células mononucleares do sangue periférico de 73 doentes com DA e
74 controlos a expressão de genes diretamente envolvidos na regulação e
exportação celular de Fe, utilizando a técnica de PCR quantitativo. Os resultados
mostraram uma diminuição significativa na expressão dos genes
aconitase (ACO1; P=0,007); ceruloplasmina (CP; P<0,001) e proteína precursora
de beta amilóide (APP; P=0,006) em doentes com DA comparativamente
com os voluntários saudáveis. Estas observações apontam para
uma diminuição significativa da expressão dos genes associados com a
exportação de Fe celular mediada pela ferroportina na DA. Assim, o presente
estudo reforça resultados anteriores que mostram alterações no metabolismo
do Fe e podem estar na origem da retenção intracelular deste
metal e aumento de stress oxidativo caraterísticos desta patologia.A dysregulation of iron (Fe) metabolism in Alzheimer’s disease (AD) has
been suggested previously. Herein, we intended to further clarify the
molecular mechanisms underlying Fe homeostasis in AD particularly
at the level of cellular iron efflux. Thus, the expression of specific Fe
metabolism-related genes directly involved in Fe regulation and export
was assessed by quantitative PCR in peripheral blood mononuclear cells
(PBMCs) from 73 AD patients and 74 controls. A significant decrease
in the expression of aconitase 1 (ACO1; P=0.007); ceruloplasmin (CP;
P<0.001) and amyloid peptide precursor (APP; P=0.006) genes was fund
in AD patients compared with healthy volunteers. These observations
point out to a significant downregulation of the expression of genes associated
with ferroportin-mediated cellular Fe export in PBMCs from
AD patients. The present findings support previous studies suggesting
impairment of Fe homeostasis in AD, which may lead to cellular Fe retention
and oxidative stress, a typical feature of this disease
Processing of Apeiba tibourbou Aubl. extract via spray drying
The effects of drying air inlet temperature (IT) and concentration of Aerosil® 200 (CA) on several properties of spray-dried Apeiba tibourbou extracts were investigated following a 32 full factorial design. Powder recovery varied from 9.83 to 46.95% and dried products showed moisture contents below 7%. Although the spray-dried products lost some of their polyphenols, they still present excellent antioxidant activity, opening perspectives for its use to medicinal purpose. CA exerted a key role on the properties of spray-dried extracts, while IT did not present a significative influence. Aerosil® 200 proved to be an interesting alternative as an excipient for the drying of the herbal extract, even at intermediate concentrations such as 15%. The best combination of conditions to use for obtaining dry A. tibourbou extracts with adequate physicochemical and functional properties involves an IT of 100 ºC and a CA of 15%.Colegio de Farmacéuticos de la Provincia de Buenos Aire
Nitrogen Transfer from Cover Crop Residues to Onion Grown under Minimum Tillage in Southern Brazil
Validated HPLC-PDA method for rosmarinic acid quantification in Rosemary
A fast and simple HPLC-PDA method for rosmarinic acid quantification in Rosemary leaves powder was validated. The analyses were performed using a C18 column in isocratic conditions and detection at 254 nm. Performing the system suitability tests, the method showed to be capable of providing data of acceptable quality. Results showed that the method was selective, linear for concentration ranges between 2.5-50 μg.mL–1 , sensitive, precise, accurate and robust. The main advantages of the method were the simplicity and promptness of sample analysis, as well as equipment convenience. These results allowed us to conclude that it can be successfully applied on the routinely quality control of Rosemary phytopharmaceuticals inputs.Colegio de Farmacéuticos de la Provincia de Buenos Aire
Pediatric tuberculosis in the metropolitan area of Rio de Janeiro
Aim: To evaluate the clinical characteristics, diagnostic approach, and treatment outcomes of tuberculosis (TB) in children living in a high-burden metropolitan area. Methods: This was a retrospective study, based on a medical chart review, involving children under 15 years old treated for TB between 2007 and 2016, in four primary health units (PHU) and three reference centers (RC) in five cities of Rio de Janeiro metropolitan area. Factors associated with TB treatment setting, microbiological diagnosis, and treatment outcomes were evaluated. Results: A total of 544 children were enrolled; 71% were treated in PHU, 36% were under 5 years old, and 72% had pulmonary TB (PTB). The HIV prevalence was 10% (31/322). Fifty-three percent had at least one microbiological test for TB, 68% of them (196/287) had TB confirmed. Among 222 children with previous TB contact, information on LTBI was available for 78 (35%), and only 17% (13/78) were treated. Extrapulmonary TB (56% vs 32%), microbiologically confirmed TB (77% vs 60%), and HIV positivity (18.5% vs 4.0%) were significantly more frequent in RC. Treatment in RC (odds ratio (OR) 3.08, 95% confidence interval (CI) 1.74–5.44) and PTB (OR 2.47, 95% CI 1.34–4.56) were independently associated with a microbiological diagnosis of TB. The treatment success rate was 85%. In the logistic regression analysis, HIV-infected children had a 2.5-fold higher risk of an unfavorable outcome (OR 2.53, 95% CI 1.0–6.38; p = 0.05). Conclusions: Opportunities for TB prevention and early TB treatment are missed due to suboptimal close contact screening. Microbiological diagnosis of TB and drug susceptibility testing in children should be made available through more sensitive and accessible tests
Estimativa de potenciais técnicos de energia renovável em Portugal: eólico, solar fotovoltaico, solar concentrado, biomassa e oceanos
Executive Summary: There is a clear need to accelerate the energy transition, including the implementation of renewable electricity production plants, as well as the increase in consumption of other renewable energy carriers in buildings, industry, transport and other sectors. This work provides key information to make this transition possible, that is, the technical renewable energy potentials for Portugal. The aim is thus to contribute to policy support, as well as to decision-making by various Portuguese stakeholders (public and private) in the domains of energy, energy transition and greenhouse gases emissions mitigation. The work presents the technical renewable energy potentials for Portugal to: (i) decentralized solar photovoltaic (PV) plants in artificialized (or built-up) areas; (ii) centralized solar PV plants in non-artificialized (or natural) areas; (iii) concentrated solar power; (iv) onshore wind; (v) offshore wind (floating and fixed); (vi) bioenergy, and (vii) solar thermal. The wave energy primary energy resource potential is also presented (not the technical potential). The technical potential values of renewable energy sources (RES) presented are dynamic values, given the substantial uncertainty associated with their estimation. The study identifies technical RES potentials i.e., the technically viable energy generation achievable from a specific technology, considering the primary energy resource available and the geographic, environmental and land use limitations. RES economic potentials represent the fraction of RES technical potential that is economically viable, but they are not presented in this work. Likewise, this report does not address market potential, that translate the capacity and energy generation that the market effectively manages to implement. The presented RES technical potentials include the total capacity currently installed in the country. The technical potentials are estimated mostly for mainland Portugal, in most cases with a spatial disaggregation of at least NUT2 and sometimes for NUT5 and/or type of building. Despite adopting an approach based on a territorial analysis in which some areas of the country are excluded, this potential does not correspond to the work done in mapping less-sensitive areas towards future definition of RES “Go-To Areas”. The decentralized solar PV potential in artificialized areas is divided into 6 area types: industrial areas; commercial buildings; residential and mixed-use buildings; villas; health, education, cultural, tourist and military buildings, and other land uses (including parking lots and patios, ports, waste and wastewater treatment infrastructure, sports facilities, among others). It is estimated a technical potential of 23.33 GW that could generate up to 36.84 TWh/year. This potential is distributed throughout the entire territory of mainland Portugal but is higher in the North and Center regions. The RES technical potential for centralized solar PV was estimated as a range of values that translate the uncertainty associated with using different levels of concern in excluding certain areas in which solar PV can be deployed (for example to safeguard ecosystems, water resources, agriculture or archaeological heritage). The centralized solar PV potential varies between 168.82 GW and 45.63 GW. The maximum threshold of installed capacity could generate 278.11 TWh/year of electricity. The value is high and reflects on the one hand, the excellence of the solar resource throughout the country, and on the other, the large size of the considered areas. The CSP potential is 62.6 GW with a corresponding electrical production potential of 183.61 TWh/year. It is mainly located in the Alentejo region, although other areas have also been identified in other regions of the country. The wind onshore technical potential is 15.7 GW, that could generate 37.13 TWh/year, taking into account the safeguarding of various areas for the protection of ecosystems and also social acceptability issues. In the case of offshore wind and considering a capacity density of 4 MW/km2 for floating offshore and 5.5 MW/km2 for fixed offshore, a total of 36 GW and 2 GW are obtained, respectively. This capacity could generate up to 126.14 TWh/year (floating offshore) or 6.31 TWh/year (fixed offshore). The solar thermal energy potential focused residential and service buildings (such as nursing homes, barracks, etc., tourism, hospitals, indoor swimming pools and other sports facilities). The potential is of 0.95 GWt and 0.95 TWh/year for service buildings, 7.26 GWt and 5.84 TWh/year for residential buildings. For industry there is a potential of 1.06 GWt, which could generate up to 1.15 TWh/year for applications up to 160 ºC. The total technical potential of solar thermal is 9.25 GWt and 7.93 TWh/year of thermal energy generated, with a substantial weight of residential buildings in the total value. Potential values are disaggregated by NUTS III and type of building. In terms of biomass and bioenergy potential, annual values of forest biomass, agricultural biomass, agro-industrial waste, urban waste and wastewater treatment are estimated, totaling around 58 TWh/year. Regarding the production of biofuels (HVO and FAME) it is estimated that the annual production of domestic used oils and other similar residues is 1.4 TWh/year. The use of oils from food crops such as soybean, sunflower and rapeseed is limited by European (and national) policy guidelines and is 2.1 TWh/year.
Regarding wave energy, the resource potential is estimated between 1.4 GW for 80 m bathymetry and 4.8 for 20 m bathymetry. There are substantial uncertainties associated with the presented values, inherent to the methodological approach considered. Nevertheless, these estimates are a valuable starting point to be refined and improved in subsequent updates.N/
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