871 research outputs found
Chemo-enzymatic saccharification strategy of microalgae chlorella sorokiniana
Biofuel production using microalgae attracted much attention because it can be cultured using CO2 and sunlight. With high carbohydrate content, microalgae have the potential to be used as a fermentation feedstock for bioethanol production. In present work, chemo-enzymatic saccharification of Chlorella sorokiniana microalgae were investigated. Chemical hydrolysis of the biomass followed by enzymatic hydrolysis and was also evaluated the effect of combining the two enzymes and the sequential addition. The effect of α-amylase concentrations was analyzed in ranged between 50 and 8000 U/g of biomass and for amyloglucosidase between 90 and 600 U/g of biomass. The higher concentrations showed the highest conversion of reducing sugars. The α-amylase concentration 8000 U/g of biomass presented a conversion of 43.06â±â2.92% (w/w), while amyloglucosidase with 600 U/g of biomass obtained 76.57â±â6.42% (w/w). The combination of two enzymes simultaneously was more efficient than the sequential addition for low enzyme concentrations (α-amylase 50 U/g and amyloglucosidase 90 U/g) with a total reducing sugar of 22.78â±â3.06 and 16.92â±â2.06% (w/w), respectively. On the other hand, using the higher enzymes concentrations, no difference was observed between the two addition strategies, 58.9â±â3.55 and 57.05â±â2.33% (w/w) for the sequential and simultaneous, respectively. Both strategies didnât present advantage, since the amyloglucosidase enzyme alone produced slightly higher results. Even thought, the obtained results showed successfully performed saccharification of microalgal biomass and clearly point to microalgae use for saccharification and subsequent bioethanol production.Part of this work has been supported by European governments (INTERREG VA-POCTEP- 2014-2020; 0055_ALGARED_PLUS_5_E) and the Portuguese Science Foundation (FCT) through the grant UID/MAR/00350/2013 to the CIMA of the University of Algarve.info:eu-repo/semantics/publishedVersio
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Vibration reduction for vision systems on board unmanned aerial vehicles using a neuro-fuzzy controller
In this paper, an intelligent control approach based on neuro-fuzzy systems performance is presented, with the objective of counteracting the vibrations that affect the low-cost vision platform onboard an unmanned aerial system of rotating nature. A scaled dynamical model of a helicopter is used to simulate vibrations on its fuselage. The impact of these vibrations on the low-cost vision system will be assessed and an intelligent control approach will be derived in order to reduce its detrimental influence. Different trials that consider a neuro-fuzzy approach as a fundamental part of an intelligent semi-active control strategy have been carried out. Satisfactory results have been achieved compared to those obtained by means of vibration reduction passive techniques
Polyfunctional T cell responses in children in early stages of chronic Trypanosoma cruzi infection contrast with monofunctional responses of long-term infected adults
Background: Adults with chronic Trypanosoma cruzi exhibit a poorly functional T cell compartment, characterized by monofunctional (IFN-Îł-only secreting) parasite-specific T cells and increased levels of terminally differentiated T cells. It is possible that persistent infection and/or sustained exposure to parasites antigens may lead to a progressive loss of function of the immune T cells. Methodology/Principal Findings: To test this hypothesis, the quality and magnitude of T. cruzi-specific T cell responses were evaluated in T. cruzi-infected children and compared with long-term T. cruzi-infected adults with no evidence of heart failure. The phenotype of CD4+ T cells was also assessed in T. cruzi-infected children and uninfected controls. Simultaneous secretion of IFN-Îł and IL-2 measured by ELISPOT assays in response to T. cruzi antigens was prevalent among T. cruzi-infected children. Flow cytometric analysis of co-expression profiles of CD4+ T cells with the ability to produce IFN-Îł, TNF-α, or to express the co-stimulatory molecule CD154 in response to T. cruzi showed polyfunctional T cell responses in most T. cruzi-infected children. Monofunctional T cell responses and an absence of CD4+TNF-α+-secreting T cells were observed in T. cruzi-infected adults. A relatively high degree of activation and differentiation of CD4+ T cells was evident in T. cruzi-infected children. Conclusions/Significance: Our observations are compatible with our initial hypothesis that persistent T. cruzi infection promotes eventual exhaustion of immune system, which might contribute to disease progression in long-term infected subjects.Fil: Albareda, MarĂa Cecilia. DirecciĂłn Nacional de Instituto de InvestigaciĂłn. AdministraciĂłn Nacional de Laboratorio e Instituto de Salud. Instituto Nacional de ParasitologĂa; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. Provincia de Buenos Aires. Ministerio de Salud. Hospital Interzonal de Agudos "Eva PerĂłn"; ArgentinaFil: de Rissio, Ana MarĂa. DirecciĂłn Nacional de Instituto de InvestigaciĂłn. AdministraciĂłn Nacional de Laboratorio e Instituto de Salud. Instituto Nacional de ParasitologĂa; ArgentinaFil: Tomas, Gonzalo. DirecciĂłn Nacional de Instituto de InvestigaciĂłn. AdministraciĂłn Nacional de Laboratorio e Instituto de Salud. Instituto Nacional de ParasitologĂa; ArgentinaFil: Serjan, Alicia. Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Juan A. FernĂĄndez"; ArgentinaFil: Alvarez, MarĂa Gabriela. Provincia de Buenos Aires. Ministerio de Salud. Hospital Interzonal de Agudos "Eva PerĂłn"; ArgentinaFil: Viotti, Rodolfo Jorge. Provincia de Buenos Aires. Ministerio de Salud. Hospital Interzonal de Agudos "Eva PerĂłn"; ArgentinaFil: Fichera, Laura Edith. DirecciĂłn Nacional de Instituto de InvestigaciĂłn. AdministraciĂłn Nacional de Laboratorio e Instituto de Salud. Instituto Nacional de ParasitologĂa; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Esteva, MĂłnica InĂ©s. DirecciĂłn Nacional de Instituto de InvestigaciĂłn. AdministraciĂłn Nacional de Laboratorio e Instituto de Salud. Instituto Nacional de ParasitologĂa; ArgentinaFil: Potente, Daniel Fernando. Provincia de Buenos Aires. Ministerio de Salud. Hospital Interzonal de Agudos "Eva PerĂłn"; ArgentinaFil: Armenti, Alejandro. Provincia de Buenos Aires. Ministerio de Salud. Hospital Interzonal de Agudos "Eva PerĂłn"; ArgentinaFil: Tarleton, Rick L.. University of Georgia; Estados UnidosFil: Laucella, Susana Adriana. DirecciĂłn Nacional de Instituto de InvestigaciĂłn. AdministraciĂłn Nacional de Laboratorio e Instituto de Salud. Instituto Nacional de ParasitologĂa; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentin
Primary bilateral adrenal B-cell lymphoma associated with EBV and JCV infection
Primary lymphoma of the adrenal gland is a rare and highly aggressive disease, with only a few reports in the literature. The pathogenesis is unknown, but detection of Epstein Barr virus (EBV) genome sequences and gene expression in some cases of primary adrenal lymphomas suggested the virus might be a causative agent of the malignancy. While investigating the presence of genome sequences of oncogenic viruses in a large series of adrenal tumors, both EBV and JC polyomavirus (JCV) DNA sequences were detected in a diffuse large primary bilateral B-cell non-Hodgkin lymphoma of the adrenal gland, which was diagnosed only at postmortem examination in a 77 year-old woman with incidentally discovered adrenal masses and primary adrenal insufficiency. The presence of both EBV and JCV genome sequences suggests the relevance of EBV and JCV coinfection in the pathogenesis of this rare form of B-cell lymphoma
The Submarine Volcano Eruption off El Hierro Island: Effects on the Scattering Migrant Biota and the Evolution of the Pelagic Communities
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Prevalence and socio-demographic correlates of physical activity levels among South African adults in Cape Town and Mount Frere communities in 2008-2009
BACKGROUND: Physical activity has been linked to reduced risk of various cardiometabolic disease, cancer, and
premature mortality. We investigated the prevalence and socio-demographic correlates of physical activity
among adults in urban and rural communities in South Africa. METHODS: This was a cross-sectional survey
comprising 1733 adults aged ?35 years from the Cape Town (urban) and Mount Frere (rural) sites of the
Prospective Urban Rural Epidemiology study. Physical activity was assessed using the validated International
Physical Activity Questionnaire. Multinomial logistic regressions were used to relate physical activity with
socio-demographic characteristics.
RESULTS: Overall, 74% of participants engaged in moderate-to-vigorous physical activity. In the adjusted regression
models, women were 34% less likely to engage in vigorous physical activity (OR =0.66, 95%-CI = 0.47-0.93). Physical
activity decreased with age, varied with marital status, education and occupation, always in differential ways
between urban and rural participants (all interactions p ? 0.047). For instance, in urban settings, those with
secondary education were more likely to engage in moderate physical activity (OR = 2.06, 95%-CI = 1.08-3.92)
than those with tertiary education. Single people were more likely to engage in high physical activity (OR = 2.10,
95%-CI = 1.03-4.28) than divorced. Overall, skilled participants were more likely to engage in vigorous physical
activity (OR = 2.07, 95%-CI = 1.41-3.05) driven by significant effect in rural area (OR = 2.70, 95%-CI = 1.51-4.83).
Urban participants were more likely to engage in moderate physical activity (OR = 1.67, 95%-CI = 1.31-2.13)
than rural participants.
CONCLUSIONS: To prevent chronic diseases among South Africans, attention should be paid to specific policies
and interventions aimed at promoting PA among young adults in rural and urban setting, and across the
social-economic diversity
Plastisol Foaming Process. Decomposition of the Foaming Agent, Polymer Behavior in the Corresponding Temperature Range and Resulting Foam Properties
The decomposition of azodicarbonamide, used as foaming agent in PVC - plasticizer (1/1) plastisols was studied by DSC. Nineteen different plasticizers, all belonging to the ester family, two being polymeric (polyadipates), were compared. The temperature of maximum decomposition rate (in anisothermal regime at 5 K min-1 scanning rate), ranges between 434 and 452 K. The heat of decomposition ranges between 8.7 and 12.5 J g -1. Some trends of variation of these parameters appear significant and are discussed in terms of solvent (matrix) and viscosity effects on the decomposition reactions. The shear modulus at 1 Hz frequency was determined at the temperature of maximum rate of foaming agent decomposition, and differs significantly from a sample to another. The foam density was determined at ambient temperature and the volume fraction of bubbles was used as criterion to judge the efficiency of the foaming process. The results reveal the existence of an optimal shear modulus of the order of 2 kPa that corresponds roughly to plasticizer molar masses of the order of 450 ± 50 g mol-1. Heavier plasticizers, especially polymeric ones are too difficult to deform. Lighter plasticizers such as diethyl phthalate (DEP) deform too easily and presumably facilitate bubble collapse
Observation of associated near-side and away-side long-range correlations in âsNN=5.02ââTeV proton-lead collisions with the ATLAS detector
Two-particle correlations in relative azimuthal angle (ÎÏ) and pseudorapidity (Îη) are measured in âsNN=5.02ââTeV p+Pb collisions using the ATLAS detector at the LHC. The measurements are performed using approximately 1ââÎŒb-1 of data as a function of transverse momentum (pT) and the transverse energy (ÎŁETPb) summed over 3.1<η<4.9 in the direction of the Pb beam. The correlation function, constructed from charged particles, exhibits a long-range (2<|Îη|<5) ânear-sideâ (ÎÏâŒ0) correlation that grows rapidly with increasing ÎŁETPb. A long-range âaway-sideâ (ÎÏâŒÏ) correlation, obtained by subtracting the expected contributions from recoiling dijets and other sources estimated using events with small ÎŁETPb, is found to match the near-side correlation in magnitude, shape (in Îη and ÎÏ) and ÎŁETPb dependence. The resultant ÎÏ correlation is approximately symmetric about Ï/2, and is consistent with a dominant cosâĄ2ÎÏ modulation for all ÎŁETPb ranges and particle pT
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