The world tendency in last years is to restrict the use of fossil fuels and replace them partially or totally by renewable fuels. Accordingly, biodiesel is being studied as one of the main ...alternatives and the production and consumption of this pure biofuel and its binary blends with fossil diesel have been markedly grown. Thus, the present work evaluated the influence of biodiesel concentration on such blends when mixed to diesel in 5, 15, 25 and 50 volume percentages. For each blend, both methanol and ethanol biodiesels were investigated. The biodiesel samples were physicochemically characterized. Their rheological behavior was analyzed. It was observed that the biodiesel enrichment leads to an acceptable increase in the viscosity and to a decrease in the volatilization of the binary blends. The viscosity was also shown to be temperature-dependent, as well as the fatty acids chain length and unsaturation.
A manifestation of the Pan-African-Brasiliano orogeny (700–550Ma) in northeastern Brazil was the emplacement of widespread Neoproterozoic granitoids in diverse tectonic terranes. Among these plutons ...are the magmatic epidote-bearing Conceição das Creoulas, Caldeirão Encantado, Murici, and Boqueirão plutons, located close to the boundary between the Alto Pajeú and Cachoeirinha–Salgueiro terranes. The plutons are high-K calc-alkalic granodiorites to monzogranites, with tabular K-feldspar megacrysts.
Pistacite atomic Fe+3/(Fe3++Al) in epidote in these granitoids ranges from 21 to 27%. High oxygen fugacity (log fO2 −19 to −13) and the preservation of epidote suggest that the magma was oxidized. Al-in-hornblende barometry indicates hornblende solidification between 6 and 8kbar, at 620 to 780°C according to the hornblende–plagioclase thermometer. Zircon saturation thermometry attests to a near-liquidus temperature range from 794 to 853°C.
Partial corrosion of magmatic epidote in these four plutons occurred during an interval of no more than 10–30years, which corresponds to maximum magma ascent rates of 650–1000m/year. Diking, associated with regional shearing, probably facilitated rapid transport of granitic magma through hot continental crust at peak metamorphism, and permitted survival of epidote that was out of equilibrium at the low pressure of final emplacement.
Similarities between mineralogical composition, chemistry, and isotopic compositions (εNd(0.60Ga) between −2 and −5,TDM from 1.2 to 1.3Ga, δ18O values>10‰, V-SMOW) of these four plutons and Neoproterozoic magmatic epidote-bearing plutons elsewhere in northeastern Brazil, argue for similar metabasaltic/mafic sources that had previously experienced low-temperature alteration.
► Four high-K calc-alkalic plutons display igneous epidote in NE Brazil. ► Measured partial corrosion of epidote records speed rates lesser than 1000m/year. ► Shearing allowed rapid magma transport through hot crust at peak of metamorphism.
Calc-alkalic to high-K calc-alkalic granitoid plutons in the Borborema province, northeastern Brazil, have been studied to constrain depth of emplacement by mineralogical and geological methods and ...to estimate upward magma transport rate based on partial dissolution of magmatic epidote.
Laser-probe incremental heating
40Ar/
39Ar dating of biotite and hornblende single crystals from the Neoproterozoic Tavares and Brejinho high-K calc-alkalic magmatic epidote (mEp)-bearing plutons reveals age differences of around 60 M.y. between these two minerals in each of these two intrusions. These data suggest solidification at relatively great depth followed by prolonged cooling interval between the closure temperatures of biotite and hornblende.
Al-in-hornblende barometry indicates that hornblende in several mEp-bearing plutons in the Transversal Domain of the Borborema province solidified at 5 to 7 kbar, whereas in the Seridó and Macururé terranes, solidification pressures range from 3 to 4 kbar.
Partial dissolution of epidote indicates very rapid upward transport. Partial corrosion occurred during 15–35 years (Cachoerinha–Salgueiro terrane), 10–30 years (Alto Pajeú), 15 years (Seridó), and 10 years (Macururé) corresponding to upward transport rates of 450–1300, 650–1050, 1200, and 1800 m/year respectively in these four terranes. Rapid upward magma migration in most cases was probably facilitated by diking simultaneous with regional shearing.
The search for molecular markers to improve diagnosis, individualize treatment and predict behavior of tumors has been the focus of several studies. This study aimed to analyze homeobox gene ...expression profile in oral squamous cell carcinoma (OSCC) as well as to investigate whether some of these genes are relevant molecular markers of prognosis and/or tumor aggressiveness. Homeobox gene expression levels were assessed by microarrays and qRT-PCR in OSCC tissues and adjacent non-cancerous matched tissues (margin), as well as in OSCC cell lines. Analysis of microarray data revealed the expression of 147 homeobox genes, including one set of six at least 2-fold up-regulated, and another set of 34 at least 2-fold down-regulated homeobox genes in OSCC. After qRT-PCR assays, the three most up-regulated homeobox genes (HOXA5, HOXD10 and HOXD11) revealed higher and statistically significant expression levels in OSCC samples when compared to margins. Patients presenting lower expression of HOXA5 had poorer prognosis compared to those with higher expression (P=0.03). Additionally, the status of HOXA5, HOXD10 and HOXD11 expression levels in OSCC cell lines also showed a significant up-regulation when compared to normal oral keratinocytes. Results confirm the presence of three significantly upregulated (>4-fold) homeobox genes (HOXA5, HOXD10 and HOXD11) in OSCC that may play a significant role in the pathogenesis of these tumors. Moreover, since lower levels of HOXA5 predict poor prognosis, this gene may be a novel candidate for development of therapeutic strategies in OSCC.
Aims: The incidence of head and neck cancer (HNC) in Brazil has increased substantially in recent years. This increase is likely to be strongly associated with alcohol and tobacco consumption, but ...genetic susceptibility also should be investigated in this population. The aim of this study was to evaluate the association of polymorphisms in genes of alcohol metabolism enzymes and the risk of HNC. Methods: A hospital-based case–control study was conducted in São Paulo, Brazil. We here investigated ADH1C Ile350Val, ADH1B Arg48His, ADH1B Arg370Cys and CYP2E1*5A PstI polymorphisms by PCR-RFLP Polymerase Chain Reaction - Restriction Fragment Length Polymorphism in 207 histopathologically confirmed HNC cases (184 males and 23 females) and 244 cancer-free controls (225 males and 19 females) admitted as in-patients in the same hospital. Results: Chronic alcohol intake increased approximately four times the risk of HNC. The mutant genotype ADH1B Arg48His was more frequent in controls (12.7%) than HNC patients (5.8%) conferring protection for the disease (odds ratio (OR) = 0.42; 95% confidence interval (CI ), 0.21–0.85). Similar results were observed for individuals with ADH1B*2 (OR = 0.41; 95% CI , 0.20–0.82) or ADH1B*2/ADH1C*1 (OR = 0.32; 95% CI , 0.13–0.79) mutated haplotypes. Multiple regression analyses showed that individuals with the mutant genotype ADH1B Arg48His who consume alcohol >30 g/L/day have more than four times the risk for HNC (OR = 4.42; 95% CI, 1.21–16.11). Conclusions: The fast alcohol metabolizing genotypes may prevent HNC when the amount of alcohol intake is <30.655 g/L/day.
The standard molar enthalpy of formation of arsenic alkoxides in the liquid phase, As(OR)
3{R = ethyl (Et),
n-propyl (Pr
n),
i-propyl (Pr
i),
n-butyl (Bu
n) and
i-butyl (Bu
i)}, was determined ...through reaction-solution calorimetry in chloroform based on the reaction: As(NEt
2)
3(1) + 3ROH(1) = As(OR)
3(1); Δ
sol
H
m
oat
T= 298.15 K. This series of alkoxides gave the following molar enthalpy of formation Δ
f
H
m
ovalues: −(758.1 ± 9.0) kJ·mol
−1, −(774.3 ± 9.0) kJ·mol
−1, (−774.3 ± 9.0) kJ·mol
−1−(809.8 ± 9.0) kJ·mol
−1, (−828.8 ± 8.9) kJ·mol
−1and −(863.4 ± 8.9) kJ·mol
−1, respectively. The standard molar enthalpies of vaporization Δ
vap
H
m(47.9 ± 1.1) kJ·mol
−1, (51.2 ± 1.8) kJ·mol
−1, (80.1 ± 0.9) kJ·mol
−1, (64.0 ± 1.8) kJ·mol
−1and (75.7 ± 1.2) kJ·mol
−1, were obtained for the same sequence of alkoxides, by means of differential scanning calorimetry. By combining the preceding values with the standard molar enthalpy of formation of the alkoxide Δ
f
H
min the liquid phase, the standard molar enthalpy of formation of these compounds in the gas phase was obtained as −(710.2 ± 9.0) kJ·mol
−1, −(723.1 ± 9.1) kJ·mol
−1, −(729.3 ± 9.0) kJ·mol
−1, −(764.8 ± 9.1) kJ·mol
−1, and −(787.7 ± 9.0) kJ·mol
−1, respectively. From these values, the mean enthalpy of dissociation of the arsenic-oxygen bond <D
m>(As-O) was calculated for the sequence of the above alkoxides to give: (320 ± 5) kJ·mol
−1, (301 ± 5) kJ·mol
−1, (292 ± 5) kJ·mol
−1, (293 ± 5) kJ·mol
−1, and (294 ± 5) kJ·mol
−1. The linear correlation between the standard molar enthalpies of formation of the liquid alkoxides Δ
f
H
m{As(OR)
3(1)} and the respective alcohol Δ
f
H
m(ROH, 1) suggests that these thermochemical data can be assessed for a series of normal and iso chain alcohols.
A subject that is gaining more strength in technological scenario is the embedded system. They are present in various products, from a simple MP3 player to an aircraft with the latest technology. ...Embedded systems have limited memory resources, processing and storage. Thus, the amount of computational resources used is a factor that should be taken into account in time to develop a software. Along with the reat expansion of embedded systems, also increased the number of attacks and threats to systems. Thus, security is a key aspect of the design of these systems. Taking into account the characteristic of safety related authentication, this paper presents the energy consumption analysis between the key generators for the RSA and ECC algorithms. Cryptographic keys can be used in the authentication process between entities that are communicating, improving the security of communication. Tests to check for a possible correlation between the runtime and energy consumption were also conducted. The algorithms were implemented in C language and the executions were carried out in the BeagleBoard platform. The conclusion is that the ECC algorithm presented a lower energy consumption than the RSA algorithm and a strong correlation between runtime and power consumption.
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