886 resultados para Mathematical activity during 18th and 19th century


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The purpose of this study was to correlate the trochlear shape and patellar tilt angle and lateral patellar displacement at rest and maximal voluntary isometric contraction (MVIC) exercises during open (OKC) and closed kinetic chain (CKC) in subjects with and without anterior knee pain. Subjects were all women, 20 who were clinically healthy and 19 diagnosed with anterior knee pain. All subjects were evaluated and subjected to magnetic resonance exams during OKC and CKC exercise with the knee placed at 15, 30, and 45 degrees of flexion. The parameters evaluated were sulcus angle, patellar tilt angle and patellar displacement using bisect offset. Pearson's r coefficient was used, with p < .05. Our results revealed in knee pain group during CKC and OKC at 15 degrees that the increase in the sulcus angle is associated with a tilt increase and patellar lateral displacement. Comparing sulcus angle, patellar tilt angle and bisect offset values between MVIC in OKC and CKC in the knee pain group, it was observed that patellar tilt angle increased in OKC only with the knee flexed at 30 degrees. Based on our results, we conclude that reduced trochlear depth is correlated with increased lateral patellar tilt and displacement during OKC and CKC at 15 degrees of flexion in people with anterior knee pain. By contrast, 30 degrees of knee flexion in CKC is more recommended in rehabilitation protocols because the patella was more stable than in other positions.

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Phosphorylated poly(styrene-co-divinylbenzene) copolymers prepared by aromatic electrophilic substitution reaction with PCl3/AlCl3 were reacted with carbon dissulfite in order to introduce sulfophosphorylated groups into copolymers. These modifications were characterized by FTIR, elemental analysis, spectrophotometry, optical and scanning electron microscopy. The antibacterial activities of the phosphorylated and sulfophorylated copolymers were assessed against Escherichia coli ATCC25922 suspensions (10(3)-10(7) cells mL(-1)) using a column system. The unmodified copolymers did not have antibacterial activity against the E. coil suspensions but the phosphorylated and sulfophorylated copolymers showed significant bactericidal action for all E. coli concentrations. The sulfophosphorylated copolymers had higher antibacterial activity than the phosphorylated ones, mainly for high concentrations of E. coli cells. Published by Elsevier B.V.

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Somatic embryogenesis is an in vitro morphogenetic route in which isolated cells or a small group of somatic cells give rise to bipolar structures resembling zygotic embryos. Lipids, carbohydrates, and proteins are major compounds in plant and animal metabolism. Comparative analysis along different developmental stages of Acca sellowiana (Myrtaceae) zygotic and somatic embryos, revealed a progressive increase in levels of total lipids. A high degree of similarity could be found in the total lipids composition between A. sellowiana somatic and zygotic embryos. High lipid levels were found in zygotic embryos in the torpedo and cotyledonary stages, and these levels increased according to the progression in the developmental stages. Somatic embryos obtained through direct embryogenesis route showed higher levels of lipids than in indirect somatic embryogenesis. The compounds most frequently were linoleic acid (C18:2), palmitic (C16:0) and oleic (C18:1). These results indicate a high similarity degree of accumulation of total lipids, regardless of zygotic or somatic embryogenesis.

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Background: It is not known whether smoking by mothers during pregnancy is associated with headache in their offspring. Methods: Two prospective cohorts of 869 children aged 10-11 years from Ribeirao Preto (RP) and 805 children aged 7-9 years from Sao Luis (SL) were studied. Data on maternal smoking were collected at birth. Primary headache was defined as a reporting of >= 2 episodes of headache in the past 2 weeks, without any associated organic symptoms. Results: Prevalence of headache was 28.1% in RP and 13.1% in SL as reported by the mothers and 17.5% in RP and 29.4% in SL as reported by the children. Agreement between mothers' report and children's self-report of primary headache in the child was poor. After adjustment, children whose mothers smoked >= 10 cigarettes per day during pregnancy presented higher prevalence of primary headache than their counterparts in both cohorts, as reported by the mother and in RP as reported by the children. Conclusions: Maternal smoking during pregnancy was associated with headache in 7- to 11-year-olds. With one exception, the consistency of the results, despite poor agreement between maternal and children reports of headache, indicates that maternal smoking during pregnancy may contribute to headaches in their children.

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The Dipteran a native Brazilian insect that has become a valuable model system for developmental biology research because it provides an interesting opportunity to study a different type of insect oogenesis. Sequences from a cDNA library that was constructed with poly A + RNA from the ovaries of larvae at different ages were analyzed. Molecular characterization confirmed interesting findings, such as the presence of . The gene encodes a conserved RNA-binding protein that is required during early development for the maintenance and division of the primordial germ cells of Diptera. plays an important role in specifying the posterior regions of insect embryos and is important for abdomen formation. In the present work, we showed the spatial and temporal expression profiles of this important gene, which is involved in oogenesis and early development. Data mining techniques were used to obtain the complete sequence of . Bioinformatic tools were used to determine the following: (1) the secondary structure of the 3'-untranslated region of the mRNA, (2) the encoded protein of the isolated gene, (3) the conserved zinc-finger domains of the Nanos protein, and (4) phylogenetic analyses. Furthermore, RNA in situ hybridization and immunolocalization were used to determine mRNA and protein expression in the tissues that were studied and to define as a germ cell molecular marker.

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Dengue is the most important arbovirus in the world with an estimated of 50 million dengue infections occurring annually and approximately 2.5 billion people living in dengue endemic countries. Yellow fever is a viral hemorrhagic fever with high mortality that is transmitted by mosquitoes. Effective vaccines against yellow fever have been available for almost 70 years and are responsible for a significant reduction of occurrences of the disease worldwide; however, approximately 200,000 cases of yellow fever still occur annually, principally in Africa. Therefore, it is a public health priority to develop antiviral agents for treatment of these virus infections. Crotalus durissus terrificus snake, a South American rattlesnake, presents venom with several biologically actives molecules. In this study, we evaluated the antiviral activity of crude venom and isolated toxins from Crotalus durissus terrificus and found that phospholipases A(2) showed a high inhibition of Yellow fever and dengue viruses in VERO E6 cells. (C) 2011 Elsevier Ltd. All rights reserved.

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The study of obstructive sleep apnea (OSA) has received growing attention over the past years since various aspects have not been sufficiently established. Aim: To evaluate, with the use of magnetic resonance imaging (MRI), changes in the area of the pharynx during wakefulness and induced sleep in patients with OSA. Materials and Methods: A prospective study of thirty-two patients with a polysomnographic diagnosis of OSA. All patients were submitted to MR imaging in order to obtain high-definition anatomical sagittal sequences during wakefulness and during sleep induced with Propofol. An area was defined on the sagittal plane in the midline of the pharynx. This region was called pharyngeal midplane (PMP) area. Results: A significant difference in PMP area (mm(2)) was observed between wakefulness and induced sleep in each patient (p < 0.000001). Conclusion: The patients with OSA suffer a significant reduction of 75,5 % in the area of the pharynx during induced sleep compared to wakefulness.

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N-4-Phenyl 2-acetylpyridine thiosemicarbazone (H2Ac4Ph; N-(phenyl)-2-(1-(pyridin-2-yl)ethylidene) hydrazinecarbothioamide) and its N-4-ortho-, -meta- and -para-fluorophenyl (H2Ac4oFPh, H2Ac4mFPh, H2Ac4pFPh), N-4-ortho-, -meta- and -para-chlorophenyl (H2Ac4oClPh, H2Ac4mClPh, H2Ac4pClPh), N-4-ortho-, -meta- and -para-iodophenyl (H2Ac4oIPh, H2Ac4mIPh, H2Ac4pIPh) and N-4-ortho-, -meta- and -para-nitrophenyl (H2Ac4oNO(2)Ph, H2Ac4mNO(2)Ph, H2Ac4pNO(2)Ph) derivatives were assayed for their cytotoxicity against human malignant breast (MCF-7) and glioma (T98G and U87) cells. The compounds were highly cytotoxic against the three cell lineages (IC50: MCF-7, 52-0.16 nM; T98G, 140-1.0 nM; U87, 160-1.4 nM). All tested thiosemicarbazones were more cytotoxic than etoposide and did not present any haemolytic activity at up to 10(-5) M. The compounds were able to induce programmed cell death. H2Ac4pClPh partially inhibited tubulin assembly at high concentrations and induced cellular microtubule disorganization. (C) 2012 Elsevier Ltd. All rights reserved.

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Selection of reference genes is an essential consideration to increase the precision and quality of relative expression analysis by the quantitative RT-PCR method. The stability of eight expressed sequence tags was evaluated to define potential reference genes to study the differential expression of common bean target genes under biotic (incompatible interaction between common bean and fungus Colletotrichum lindemuthianum) and abiotic (drought; salinity; cold temperature) stresses. The efficiency of amplification curves and quantification cycle (C (q)) were determined using LinRegPCR software. The stability of the candidate reference genes was obtained using geNorm and NormFinder software, whereas the normalization of differential expression of target genes [beta-1,3-glucanase 1 (BG1) gene for biotic stress and dehydration responsive element binding (DREB) gene for abiotic stress] was defined by REST software. High stability was obtained for insulin degrading enzyme (IDE), actin-11 (Act11), unknown 1 (Ukn1) and unknown 2 (Ukn2) genes during biotic stress, and for SKP1/ASK-interacting protein 16 (Skip16), Act11, Tubulin beta-8 (beta-Tub8) and Unk1 genes under abiotic stresses. However, IDE and Act11 were indicated as the best combination of reference genes for biotic stress analysis, whereas the Skip16 and Act11 genes were the best combination to study abiotic stress. These genes should be useful in the normalization of gene expression by RT-PCR analysis in common bean, the most important edible legume.

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The aim of the study was to screen 11 selected traditional medicinal plants from West Africa for their in vitro antiplasmodial activity in order to determine the activity of single and of combination of plant extracts and to examine the activity of isolated pure compounds. Ethanolic and aqueous extracts of the 11 selected plants and pure compounds from Phyllanthus muellerianus and Anogeissus leiocarpus were tested in vitro against Plasmodium falciparum 3D7. Proliferation inhibitory effects were monitored after 48 h. Among the plants and pure compounds investigated in this study, geraniin from P. muellerianus, ellagic, gentisic, and gallic acids from A. leiocarpus, and extracts from A. leiocarpus, P. muellerianus and combination of A. leiocarpus with P. muellerianus affected the proliferation of P. falciparum most potently. Significant inhibitory activity was observed in combination of A. leiocarpus with P. muellerianus (IC50 = 10.8 mu g/ml), in combination of A. leiocarpus with Khaya senegalensis (IC50 = 12.5 mu g/ml), ellagic acid (IC50 = 2.88 mu M), and geraniin (IC50 = 11.74 mu M). In general growth inhibition was concentration-dependent revealing IC50 values ranging between 10.8 and -40.1 mu g/ml and 2.88 and 11.74 mu M for plant extracts and pure substances respectively. Comparison with literature sources of in vivo and in vitro toxicity data revealed that thresholds are up to two times higher than the determined IC50 values. Thus, the present study suggests that geraniin from P. muellerianus; ellagic acid, gallic acid, and gentisic acid from A. leiocarpus; and combination of extracts from A. leiocarpus with either P. muellerianus or K. senegalensis could be a potential option for malaria treatment.

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Abstract Background: Coactivation may be both desirable (injury prevention) or undesirable (strength measurement). In this context, different styles of muscle strength stimulus have being investigated. In this study we evaluated the effects of verbal and visual stimulation on rectus femoris and biceps femoris muscles contraction during isometric and concentric. Methods: We investigated 13 men (age =23.1 ± 3.8 years old; body mass =75.6 ± 9.1 kg; height =1.8 ± 0.07 m). We used the isokinetic dynamometer BIODEX device and an electromyographic (EMG) system. We evaluated the maximum isometric and isokinetic knee extension and flexion at 60°/s. The following conditions were evaluated: without visual nor verbal command (control); verbal command; visual command and; verbal and visual command. In relation to the concentric contraction, the volunteers performed five reciprocal and continuous contractions at 60°/s. With respect to isometric contractions it was made three contractions of five seconds for flexion and extension in a period of one minute. Results: We found that the peak torque during isometric flexion was higher in the subjects in the VVC condition (p > 0.05). In relation to muscle coactivation, the subjects presented higher values at the control condition (p > 0.05). Conclusion We suggest that this type of stimulus is effective for the lower limbs.

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Fluoxetine (FLX) is commonly used to treat anxiety and depressive disorders in pregnant women. Since FLX crosses the placenta and is excreted in milk, maternal treatment with this antidepressant may expose the fetus and neonate to increased levels of serotonin (5-HT). Long-term behavioral abnormalities have been reported in rodents exposed to higher levels of 5-HT during neurodevelopment. In this study we evaluated if maternal exposure to FLX during pregnancy and lactation would result in behavioral and/or stress response disruption in adolescent and adult rats. Our results indicate that exposure to FLX influenced restraint stress-induced Fos expression in the amygdala in a gender and age-specific manner. In male animals, a decreased expression was observed in the basolateral amygdala at adolescence and adulthood; whereas at adulthood, a decrease was also observed in the medial amygdala. A lack of FLX exposure effect was observed in females and also in the paraventricular nucleus of both genders. Regarding the behavioral evaluation, FLX exposure did not induce anhedonia in the sucrose preference test but decreased the latency to feed of both male and female adolescent rats evaluated in the novelty-suppressed feeding test. In conclusion, FLX exposure during pregnancy and lactation decreases acute amygdalar stress response to a psychological stressor in males (adolescents and adults) as well as influences the behavior of adolescents (males and females) in a model that evaluates anxiety and/or depressive-like behavior. Even though FLX seems to be a developmental neurotoxicant, the translation of these findings to human safe assessment remains to be determined since it is recognized that not treating a pregnant or lactating woman may also impact negatively the development of the descendants.

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The purpose of this study was to analyze the influence of lactation and dry period in the constituents of lipid and glucose metabolism of buffaloes. One hundred forty-seven samples of serum and plasma were collected between November 2009 and July 2010, from properties raising Murrah, Mediterranean and crossbred buffaloes, located in the State of Sao Paulo, Brazil. Biochemical analysis was obtained by determining the contents of serum cholesterol, triglycerides, beta-hydroxybutyrate (β-HBO), non-esterified fatty acids (NEFA) and plasma glucose. Values for arithmetic mean and standard error mean were calculated using the SAS procedure, version 9.2. Tests for normality of residuals and homogeneity of variances were performed using the SAS Guide Data Analysis. Data were analyzed by ANOVA using the SAS procedure Glimmix. The group information (Lactation), Farm and Age were used in the statistical models. Means of groups were compared using Least Square Means (LSMeans) of SAS, where significant difference was observed at P ≤ 0.05. It was possible to conclude that buffaloes during peak lactation need to metabolize body reserves to supplement the lower amounts of bloodstream lipids, when they remain in negative energy balance. In the dry period, there were significant changes in the lipid profile, characterized by decrease of nutritional requirements, with consequent improvement in the general conditions of the animals.

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[EN]Carbonate system variables were measured in the South Atlantic sector of the Southern Ocean along a transect from South Africa to the southern limit of the Antarctic Circumpolar Current (ACC) from February to March 2008. Eddies detached from the retroflection of the Agulhas Current increased the gradients observed along the fronts. Minima in the fugacity of CO2, fCO2, and maxima in pH on either side of the frontal zone were observed, noting that within the frontal zone fCO2 reached maximum values and pH was at a minimum.Vertical distributions of water masses were described by their carbonate system properties and their relationship to CFC concentrations. Upper Circumpolar Deep Water (UCDW) and Lower Circumpolar Deep Water (LCDW) offered pHT,25 values of 7.56 and 7.61, respectively. The UCDW also had higher concentrations of CFC-12 (>0.2 pmol kg?1) as compared to deeper waters, revealing that UCDW was mixed with recently ventilated waters. Calcite and aragonite saturation states ( ) were also affected by the presence of these two water masses with high carbonate concentrations. The aragonite saturation horizon was observed at 1000m in the subtropical area and north of the Subantarctic Front. At the position of the Polar Front, and under the influence of UCDW and LCDW, the aragonite saturation horizon deepened from 800m to 1500m at 50.37_ S, and reached 700m south of 57.5_ S. High latitudes proved to be the most sensitive areas to predicted anthropogenic carbon increase. Buffer coefficients related to changes in [CO2], [H+] and with changes in dissolved inorganic carbon (CT)and total alkalinity (AT) offered minima values in the Antarctic IntermediateWater and UCDWlayers. These coefficients suggest that a small increase in CT will sharply decrease the status of pH and carbonate saturation. Here we present data that suggest that south of 55_ S, surface water will be under-saturated with respect to aragonite within the next few decades.