With the increase in global demand for biodiesel, first generation feedstock has drawn the attention of governmental institutions due to the correlation with large land farming areas. The second and ...third feedstock generations are greener feedstock sources, nevertheless, they require different catalytic conditions if compared with first generation feedstock. In this work, we present the synthesis and characterization of oligoesters matrices and their functionalization to act as a pseudo-homogeneous acid catalyst for biodiesel production, named Oligocat. The main advantage of Oligocat is given due to its reactional medium interaction. Initially, oligocat is a solid catalyst soluble in the alcoholic phase, acting as a homogeneous catalyst, providing better mass transfer of the catalytic groups to the reaction medium, and as the course of the reaction happens, Oligocat migrates to the glycerol phase, also providing the advantage of easy separation of the biodiesel. Oligocat was synthesized through polymerization of aromatic hydroxy acids, followed by a chemical functionalization applying the sulfonation technique. Characterization of the catalysts was carried out by infrared spectroscopy (FTIR), nuclear magnetic resonance spectroscopy (NMR), gel permeation chromatography (GPC), and thermogravimetric analysis (TGA). The synthesized oligomers presented 5357 g·mol
(Mw) and 3909 g·mol
(Mn), with a moderate thermal resistance of approximately 175 °C. By sulfonation reaction, it was possible to obtain a high content of sulphonic groups of nearly 70 mol%, which provided the catalytic activity to the oligomeric matrix. With the mentioned physical-chemical properties, Oligocat is chemically designed to convert second generation feedstock to biodiesel efficiently. Preliminary investigation using Oligocat for biodiesel production resulted in conversion rates higher than 96.5 wt.%.
Biodiesel is a fuel that can be originated from different raw materials. However, even a good quality biodiesel has its properties strongly dependent upon its fatty acid profile. For instance, ...samples with a high content of saturated fatty acids may present poor cold flow properties, meaning that they tend to solidify under low temperatures. In this work, we propose to synthesize polymer additives and apply them as cold flow improvers for palm methyl esters (biodiesel) and their blends with petrodiesel. The synthetic additives were evaluated at different concentrations to assess their effect on the pour point (PP) of the resulting neat or blended biofuel. By using 1000 ppm of poly(dodecyl acrylate‐co‐tetradecyl methacrylate), it was possible to decrease the PP of B5 (5 vol.% biodiesel + 95 vol.% diesel) and B20 (20 vol.% biodiesel + 80 vol.% diesel) to −35 °C and −14 °C, respectively, which allowed the use of these blends in regions where their flow properties would eventually be prohibitive. However, the performance of the additive on the neat fuel (B100) was negligible.
Introduction
The role of myocardial strain in risk prediction for acute myocarditis (AMC) patients, measured by cardiac magnetic resonance (CMR), deserves further investigation. Our objective was to ...evaluate the association between myocardial strain measured by CMR and clinical events in AMC patients.
Material and methods
This was a prospective single-center study of patients with AMC. We included 100 patients with AMC with CMR confirmation. The primary outcome was the composite of all-cause mortality, heart failure and AMC recurrence in 24 months. A subgroup analysis was performed on a sample of 36 patients who underwent a second CMR between 6 and 18 months. The association between strain measures and clinical events or an increase in left ventricular ejection fraction (LVEF) was explored using Cox regression analysis. Global peak radial, circumferential and longitudinal strain in the left and right ventricles was assessed. ROC curve analysis was performed to identify cutoff points for clinical event prediction.
Results
The mean follow-up was 18.7 ± 2.3 months, and the composite primary outcome occurred in 26 patients. The median LVEF at CMR at baseline was 57.5% (14.6%). LV radial strain (HR = 0.918, 95% CI: 0.858–0.982,
p
= 0.012), LV circumferential strain (HR = 1.177, 95% CI: 1.046–1.325,
p
= 0.007) and LV longitudinal strain (HR = 1.173, 95% CI: 1.031–1.334,
p
= 0.015) were independently associated with clinical event occurrence. The areas under the ROC curve for clinical event prediction were 0.80, 0.79 and 0.80 for LV radial, circumferential, and longitudinal strain, respectively. LV longitudinal strain was independently correlated with prognosis (HR = 1.282, CI 95%: 1.022–1.524,
p
= 0.007), even when analyzed together with ejection fraction and delayed enhancement. LV and right ventricle (RV) strain were not associated with an increase in LVEF. Finally, when the initial CMR findings were compared with the follow-up CMR findings, improvements in the measures of LV and RV myocardial strain were observed.
Conclusion
Measurement of myocardial strain by CMR can provide prognostic information on AMC patients. LV radial, circumferential and longitudinal strain were associated with long-term clinical events in these patients.
A variety of techniques have been employed in order to reduce problems caused by the crystallization of paraffin during the production and/or transportation of paraffin oils and derivatives. ...Methacrylate copolymers are known as additives which reduce the pour point of these oils. This paper describes the synthesis, characterization and performance evaluation of these copolymers, having as an initial step the synthesis of the alkyl methacrylate monomers by transesterification of methyl methacrylate (MMA) with C
14, C
16 and C
18 fatty alcohols. The copolymerization of these monomers with MMA was then performed, with molar ratios of 30:70, 50:50 and 70:30 for alkyl methacrylate:methyl methacrylate. All products were characterized by FTIR,
1H NMR and gel permeation chromatography (GPC). All the methacrylic copolymers lead to a large reduction in the pour point of samples of Brazilian diesel oil. Oil samples containing 50
ppm of the polymeric additive with ca. 70% octadecyl methacrylate units showed a 22
°C reduction in their pour points, thus establishing the large efficiency of the products synthesized in this work.
The use of creep feeding for preweaning piglets is important to improve the performance of the piglets. The objective of this experiment was evaluate the effect of using or altering the position of ...piglet's creep feeder during lactation on piglet's performance and on behavior of piglets and sows kept in a hot climate environment. Forty-five sows and their litters at 10 days of lactation were randomly distributed into three treatments: front feeder (FF) - near the side of the sow's head; back feeder (BF) - near the side of the rump of the sow; and no feeder (NF). All piglets were weighed individually to evaluate the average weight, weight gain and coefficient of variation of the weight. Behavior assessments of the piglets and sows were recorded in 3 period. At 15 and 21 d, piglets of the FF treatment were heavier (P ≤ 0.0001) than piglets of the other treatments. At 10-21d piglets of FF treatment had 76.2% less belly nosing behavior than the NF piglets (P=0.015). The treatments had no impact on behavior of the sows. The creep feeders positioned in the front of the farrowing crate increased piglet growth rate and decreased frequency of belly nosing behavior.
Several published studies have evaluated the problems associated with the utilization of biodiesel obtained from safflower (Carthamus tinctorius L.) oil due to the low oxidative stability, caused by ...the high content of unsaturated fatty acids. Thus, this study aimed at the extraction of safflower seed oil and its use as an unsaturation source to obtain a synthetic antioxidant. The synthesis of this phenolic additive was done by modifying its structure through the addition of hydroquinone to the unsaturation of the oil, by electrophilic substitution. It was investigated and confirmed that this reaction is promising for obtaining phenolic products, with high yields (83.5%). The product obtained in this research was evaluated as an antioxidant in commercial biodiesel by the Rancimat method, using 5000 ppm of the synthesized additive the induction period increased from 8 to 17 h (2.12 times). Therefore, this paper brought a positive response to the improvement of biodiesel oxidation stability that creates a possibility to increase the use and expansion of this fuel in the market, as utilization of the safflower seed as raw material for additives, bringing a new market for these seeds.
This is an update of the 2004 Pelotas Birth Cohort profile, originally published in 2011. In view of the high prevalence of overweight and mental health problems among Brazilian children, together ...with the availability of state-of-the-art equipment to assess body composition and diagnostic tests for mental health in childhood, the main outcomes measured in the fifth follow-up (mean age 6.8 years) included child body composition, mental health and cognitive ability. A total of 3722 (90.2%) of the original mothers/carers were interviewed and their children examined in a clinic where they underwent whole-body dual X-ray absorptiometry (DXA), air displacement plethysmography and a 3D photonic scan. Saliva samples for DNA were obtained. Clinical psychologists applied the Development and Well-Being Assessment questionnaire and the Wechsler Intelligence Scale for Children to all children. Results are being compared with those of the two earlier cohorts to assess the health effects of economic growth and full implementation of public policies aimed at reducing social inequalities in the past 30 years. For further information visit the programme website at http://www.epidemio-ufpel.org.br/site/content/coorte_2004/questionarios.php. Applications to use the data should be made by contacting 2004 cohort researchers and filling in the application form available at http://www.epidemio-ufpel.org.br/site/content/estudos/formularios.php.
Amazonian mammal diversity is exceptionally high, yet new taxonomic discoveries continue to be made and many questions remain for understanding its diversification through time and space. Here we ...investigate the diversification of spiny rats in the genus Makalata, whose species are strongly associated with seasonally flooded forests, watercourses and flooded islands. We use a biogeographical approach based on a mitochondrial cytochrome b gene through divergence time estimation and reconstruction of ancestral areas and events. Our findings indicate an ancient origin of Makalata for the Guiana Shield and Eastern Amazonia as ancestral area. A first cladogenetic event led to a phylogeographic break into two broader clades of Makalata through dispersal, implying a pattern of western/Eastern Amazonian clades coinciding with the Purus Arch (middle Miocene). Most of subclades we infer originated between the late Pliocene to the early Pleistocene, with few recent exceptions in the early Pliocene through dispersal and vicariant events. The hypothesis of rivers as dispersal barriers is not corroborated for Makalata, as expected for mammalian species associated with seasonally flooded environments. We identify two key events for the expansion and diversification of Makalata species: the presence of geologically stable areas in the Guiana and Brazilian shields and the transition from lacustrine conditions in western Amazonia (Acre system) to a river system, with the establishment of the Amazon River transcontinental system and its tributaries. Our results are congruent with older geological scenarios for the Amazon basin formation (Miocene), but we do not discard the influence of recent dynamics on some speciation events and, mainly, on phylogeographic structuring processes.
Despite progress in treatment strategies, only ~24% of pancreatic ductal adenocarcinoma (PDAC) patients survive >1 year. Our goal was to elucidate deregulated pathways modulated by microRNAs (miRNAs) ...in PDAC and Vater ampulla (AMP) cancers. Global miRNA expression was identified in 19 PDAC, 6 AMP and 25 paired, histologically normal pancreatic tissues using the GeneChip 4.0 miRNA arrays. Computational approaches were used for miRNA target prediction/identification of miRNA-regulated pathways. Target gene expression was validated in 178 pancreatic cancer and 4 pancreatic normal tissues from The Cancer Genome Atlas (TCGA). 20 miRNAs were significantly deregulated (FC≥2 and p<0.05) (15 down- and 5 up-regulated) in PDAC. miR-216 family (miR-216a-3p, miR-216a-5p, miR-216b-3p and miR-216b-5p) was consistently down-regulated in PDAC. miRNA-modulated pathways are associated with innate and adaptive immune system responses in PDAC. AMP cancers showed 8 down- and 1 up-regulated miRNAs (FDR p<0.05). Most enriched pathways (p<0.01) were RAS and Nerve Growth Factor signaling. PDAC and AMP display different global miRNA expression profiles and miRNA regulated networks/tumorigenesis pathways. The immune response was enriched in PDAC, suggesting the existence of immune checkpoint pathways more relevant to PDAC than AMP.
BACKGROUNDOral Potentially Malignant Disorders (OPMDs) are defined as lesions with a greater likelihood of progressing to cancer. Population-based studies that evaluate the prevalence of OPMDs are ...scarce in Brazil. The aim of the present study was to determine the prevalence of OPMDs and associated risk factors in a semi-urban Brazilian population. MATERIAL AND METHODSThis is a cross-sectional study, whose universe included individuals aged 40 years or older residing in a medium-sized city of northeastern Brazil. Data collection was divided into two steps: interview and oral examination. The outcome variable was the presence of OPMDs. The predictor variables were sociodemographic characteristics and risk habits. The bivariate analysis was performed through chi-square test. The crude prevalence ratios (PR) and its respective 95% confidence intervals (CI) were calculated. Poisson regression analysis with robust variance was used to calculate adjusted PRs and 95% CI. RESULTSThree hundred fourteen individuals were included in the study. When asked about risk habits, 58.9% reported being current smokers or ex-smokers and 62.2% reported being current drinkers or ex-drinkers. The prevalence of OPMDs was 7.6% and was significantly higher among individuals with black skin color (p < 0.001), alcohol users (p = 0.017), and individuals with both tobacco and alcohol habits (p = 0.012). CONCLUSIONSTherefore, the population in the present study had a high frequency of risk habits associated with PMDs of the oral cavity.
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