This paper addresses the development of a hybrid-mixed finite-element formulation for the geometrically exact quasi-static analysis of elastic planar framed structures, modeled using the ...two-dimensional Reissner beam theory. The proposed formulation relies on a modified principle of complementary energy, which involves, as independent variables, the generalized vectors of stress resultants and displacements and, in addition, a set of Lagrange multipliers used to enforce the stress continuity between elements. The adopted finite-element discretization produces numerical solutions that strongly satisfy the equilibrium differential equations in the elements, as well as the static boundary conditions. It consists, therefore, in a true equilibrium formulation for arbitrarily large displacements and rotations. Furthermore, as it does not suffer from shear locking or any other artificial stiffening phenomena, it may be regarded as an alternative to the standard displacement-based formulation. To validate and assess the accuracy of the proposed formulation, some benchmark problems are analyzed and their solutions are compared with those obtained using the standard two-node displacement-based formulation. Numerical analyses of convergence of the proposed finite-element formulation are also included.
The antioxidant properties of Amburana cearensis extract may be a useful substitute for standard cell culture medium. Thus, the aim of this study was to evaluate the effect of this extract, with or ...without supplementation, on in vitro survival and development of sheep isolated secondary follicles. After collection of the ovaries, secondary follicles were isolated and cultured for 18 days in α-MEM+ supplemented with bovine serum albumin, insulin, transferrin, selenium, glutamine, hypoxanthine and ascorbic acid (control medium) or into medium composed of different concentrations of A. cearensis extract without supplements (Amb 0.1; 0.2 or 0.4 mg/ml) or A. cearensis extract supplemented with the same substances described above for α-MEM+ supplementation. The A. cearensis supplemented medium was named Amb 0.1+; 0.2+ or 0.4+ mg/ml. There were more morphologically normal follicles in Amb 0.1 or Amb 0.4 mg/ml than in the control medium (α-MEM+) after 18 days of culture. Moreover, the percentage of antrum formation was significantly higher in Amb 0.1 or Amb 0.2 mg/ml than in α-MEM+ and Amb 0.1+ mg/ml, and similar to the other treatments. All A. cearensis extract media induced a progressive and significant increase in follicular diameter throughout the culture period. In conclusion, this study showed that 0.1 mg/ml of this extract, without supplementation, maintains follicular survival and promotes the development of ovine isolated secondary follicles in vitro. This extract can be an alternative culture medium for preantral follicle development.
The Zeeman pattern of Mn i lines is sensitive to hyperfine structure (HFS), and because of this, they respond to hectogauss magnetic field strengths differently than the lines commonly used in solar ...magnetometry. This peculiarity has been employed to measure magnetic field strengths in quiet-Sun regions, assuming the magnetic field to be constant over a resolution element. This assumption is clearly insufficient, biasing the measurements. The diagnostic potential of Mn i lines can be fully exploited only after one understands the sense and magnitude of such bias. We present the first syntheses of Mn i lines in realistic quiet-Sun model atmospheres. The Mn i lines weaken with increasing field strength. In particular, kilogauss magnetic concentrations produce Mn i lambda5538 circular polarization signals (Stokes V) that can be up to 2 orders of magnitude smaller than what the weak magnetic field approximation predicts. The polarization emerging from an atmosphere having weak and strong fields is biased toward the weak fields, and HFS features characteristic of weak fields show up even when the magnetic flux and energy are dominated by kilogauss fields. For the HFS feature of Mn i lambda5538 to disappear, the filling factor of kilogauss fields has to be larger than the filling factor of subkilogauss fields. Since the Mn i lines are usually weak, Stokes V depends on magnetic field inclination according to the simple cosine law. Atmospheres with unresolved velocities produce very asymmetric line profiles, which cannot be reproduced by simple one-component model atmospheres. Using the HFS constants available in the literature, we reproduce the observed line profiles of nine lines with varied HFS patterns.
Aim To evaluate the flow characteristics of AH Plus, Epiphany Root Canal Sealant, Endométhasone, Pulp Canal Sealer (EWT) and Sealapex and their ability to fill artificial lateral canals and prevent ...microleakage.
Methodology Flow of the sealers was analysed using the American Dental Association (ADA) 57 and the International Standards Organization (ISO) 6876 specifications. Two lateral canals were produced in the middle and apical third of 64 roots using 0.1 mm cylindrical drills. Lateral condensation of gutta‐percha or Resilon and one or other of the sealers were used to fill the root canals. Buccal‐lingual digital radiographs were exposed. After the sealer had set, the roots were immersed in Indian ink and cleared in methyl salicylate. The extent of filling and dye penetration were measured on the buccal and lingual root surfaces under 30× magnification with a stereoscope.
Results AH Plus, Epiphany and Pulp Canal Sealer (EWT) complied with ADA 57 and ISO 6876 specifications. Sealapex complied with the ADA 57 specification but not with ISO 6876. Endométhasone did not comply with either specification. Filling of lateral canals was similar for the five sealers tested. Dye leakage demonstrated that AH Plus, Epiphany and Sealapex permitted less leakage than Pulp Canal Sealer (EWT) (P < 0.05).
Conclusions All the sealers flowed into the 0.1 mm artificial lateral canals. AH Plus, Epiphany and Sealapex allowed less linear leakage than Pulp Canal Sealer (EWT). The flow of Endométhasone did not comply with either ADA 57 or ISO 6876 specifications and Sealapex did not comply with ISO 6876.
Abstract
Iberian (IB, n = 60) and crossbred Large White × Landrace (F1, n = 58) pigs were slaughtered at 160 kg, after finishing under intensive conditions or on pasture and acorns. The study was ...carried out as a factorial arrangement of treatments, and physicochemical properties and sensory attributes of meat were assessed in Longissimus thoracis samples. Physical characteristics included the assessment of drip loss, cooking loss, shear force, and color coordinates in meat samples processed at 2 and 9 d postmortem. The interactions of genetic group and finishing system were significant (P < 0.05) for cooking loss in meat aged for 9 d and for sensorial tenderness and global acceptability of meat, but none of the other physicochemical, color coordinates, and sensory variables analyzed showed a significant interaction. Genetic group was the main factor influencing the variables analyzed, with a major (P < 0.01) influence on all meat physicochemical characteristics and sensory attributes. Relative to F1 pigs, the IB produced meat with higher intramuscular fat content and marbling score, more appealing color coordinates, lower shear force, and higher sensorial tenderness. The finishing systems affected (P < 0.05) most physical characteristics, but not chemical composition of meat and their impact on sensory properties was small. The tenderness, juiciness, and global acceptability of meat were much higher in IB pigs, and flavor was also more desirable, but the difference was smaller. The differences in sensory properties between meats originating from the two genetic groups were largely explained by the higher fat deposition in IB pigs, such that a higher level of marbling was positively associated with all the sensory attributes evaluated. Ageing meat for up to 9 d postmortem benefited pork quality, improving meat tenderness, and color, particularly in crossbred pigs and those finished intensively.
1 Center of Biology, Department of Biology, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal
2 Centro de Recursos Microbiológicos (CREM), Biotechnology Unit, Faculty of Sciences and ...Technology, New University of Lisbon, 2829-516 Caparica, Portugal
3 Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal
Correspondence M. J. Sousa mjsousa{at}bio.uminho.pt
The highly osmo- and cryotolerant yeast species Torulaspora delbrueckii is an important case study among the non- Saccharomyces yeast species. The strain T. delbrueckii PYCC 5321, isolated from traditional corn and rye bread dough in northern Portugal, is considered particularly interesting for the baking industry. This paper reports the sugar utilization patterns of this strain, using media with glucose, maltose and sucrose, alone or in mixtures. Kinetics of growth, biomass and ethanol yields, fermentation and respiration rates, hydrolase activities and sugar uptake rates were used to infer the potential applied relevance of this yeast in comparison to a conventional baker's strain of Saccharomyces cerevisiae . The results showed that both maltase and maltose transport in T. delbrueckii were subject to glucose repression and maltose induction, whereas invertase was subject to glucose control but not dependent on sucrose induction. A comparative analysis of specific sugar consumption rates and transport capacities suggests that the transport step limits both glucose and maltose metabolism. Specific rates of CO 2 production and O 2 consumption showed a significantly higher contribution of respiration to the overall metabolism in T. delbrueckii than in S. cerevisiae . This was reflected in the biomass yields from batch cultures and could represent an asset for the large-scale production of the former species. This work contributes to a better understanding of the physiology of a non-conventional yeast species, with a view to the full exploitation of T. delbrueckii by the baking industry.
These authors contributed equally to this work.
Previous functional magnetic resonance imaging (fMRI) studies examined neural activity responses to emotive stimuli in healthy individuals after acute/subacute administration of antidepressants. We ...now report the effects of repeated use of the antidepressant clomipramine on fMRI data acquired during presentation of emotion-provoking and neutral stimuli on healthy volunteers. A total of 12 volunteers were evaluated with fMRI after receiving low doses of clomipramine for 4 weeks and again after 4 weeks of washout. Fear-, happiness-, anger-provoking and neutral pictures from the International Affective Picture System (IAPS) were used. Data analysis was performed with statistical parametric mapping (P < 0.05). Paired t-test comparisons for each condition between medicated and unmedicated states showed, to negative valence paradigms, decrease in brain activity in the amygdala when participants were medicated. We also demonstrated, across both positive and negative valence paradigms, consistent decreases in brain activity in the medicated state in the anterior cingulate gyrus and insula. This is the first report of modulatory effects of repeated antidepressant use on the central representation of somatic states in response to emotions of both negative and positive valences in healthy individuals. Also, our results corroborate findings of antidepressant-induced temporolimbic activity changes to emotion-provoking stimuli obtained in studies of subjects treated acutely with such agents.
The administration of lipid nanoparticles (LNP) by different routes involves technological challenges, particularly those associated with sterilization and stability. Publications suggest that the ...stability of LNP formulations throughout the harsh production conditions involved in pharmaceutical procedures is highly dependent on the type of surfactant used. Therefore, the capacity of tripalmitin‐based LNP to withstand moist heat sterilization and freeze‐drying has been evaluated using poly (vinyl alcohol), soya lecithin, polysorbate 20, and sodium deoxycholate as emulsion stabilizers. For comparison purposes, a formulation containing diethylene glycol monoethyl ether (Transcutol® CG) was also studied. Formulations were submitted to autoclaving (at 105 or 121°C), fractional sterilization (80 or 60°C/30 min/3 days), freeze‐drying, and stored at 5 ± 3°C for 6 months. Physical stability was evaluated using relevant parameters such as particle size, polydispersion index (PI), and ζ potential. Thermal analysis and dynamic light‐scattering studies were performed and the effect of parabens was also investigated to assess its influence on physical stability. The type of emulsifier plays a crucial role in the physical stability of LNP exposed to moist‐heat sterilization and freeze‐drying, but the inclusion of a liquid lipid had a clear stabilizing effect. Stability also improved after the addition of parabens, especially the formulation containing lecithin. Practical applications: The physical stability of LNP throughout relevant harsh processes, such as moist heat sterilization and freeze‐drying, is still an issue that needs further technological studying. Nevertheless, this work demonstrates that suitable and stable LNP may be prepared and exposed to moist heat sterilization and freeze‐drying, depending on the type of emulsifier. The use of a liquid lipid contributed to the stabilization of tripalmitin‐based LNP. Finally, formulations prepared with parabens present during emulsification were more stable than those supplemented with preservatives after preparation. The physical stability of tripalmitin lipid nanoparticles throughout pharmaceutically relevant manufacturing processes, such as moist heat sterilization and freeze‐drying was addressed. Stability depends on the presence of important components such as liquid lipids and on the type of emulsifier used. Lecithin and parabens play a crucial role in LNP stabilization throughout moist heat sterilization and freeze‐drying.
Single-blind randomized, controlled clinical study.
To evaluate, using kinematic gait analysis, the results obtained from gait training on a treadmill with body weight support versus those obtained ...with conventional gait training and physiotherapy.
Thirty patients with sequelae from traumatic incomplete spinal cord injuries at least 12 months earlier; patients were able to walk and were classified according to motor function as ASIA (American Spinal Injury Association) impairment scale C or D.
Patients were divided randomly into two groups of 15 patients by the drawing of opaque envelopes: group A (weight support) and group B (conventional). After an initial assessment, both groups underwent 30 sessions of gait training. Sessions occurred twice a week, lasted for 30 min each and continued for four months. All of the patients were evaluated by a single blinded examiner using movement analysis to measure angular and linear kinematic gait parameters. Six patients (three from group A and three from group B) were excluded because they attended fewer than 85% of the training sessions.
There were no statistically significant differences in intra-group comparisons among the spatial-temporal variables in group B. In group A, the following significant differences in the studied spatial-temporal variables were observed: increases in velocity, distance, cadence, step length, swing phase and gait cycle duration, in addition to a reduction in stance phase. There were also no significant differences in intra-group comparisons among the angular variables in group B. However, group A achieved significant improvements in maximum hip extension and plantar flexion during stance.
Gait training with body weight support was more effective than conventional physiotherapy for improving the spatial-temporal and kinematic gait parameters among patients with incomplete spinal cord injuries.
The transformation of byproducts and wastes generated by agro-food companies is of high importance since only a small portion of plant material is utilized directly for human consumption. Squash ...pumpkin is greatly used in Portugal and as by-products of its processing are generated tons of shell and seeds. In this study we aim to evaluate the potential of these wastes as sources of beneficial and bioactive compounds (antioxidants and antimicrobials), studying the effect of different extraction solvents and drying methods. The samples (fresh and cooked) were freeze-dried and oven-dried followed by extraction with different solvents that revealed the following decreasing order of efficiency: 70 % ethanol, 70 % methanol, 70 % acetone, ultra-pure water and 100 % dichloromethane. The oven-dried samples showed higher values of antioxidant activity and phenolic content, with exception of the values of phenolics for the seeds material. The shell samples presented higher values (1.47 – 70.96 % inhibition) of antioxidant activity and total phenolic content (2.00 – 10.69 mg GAE/g DW). A positive correlation was found between these two parameters on the shell samples, however the squash seeds revealed a negative correlation between the phenolic content and the antioxidant activity. The results show that these industrial agro-food residues are potentially good sources of bioactive compounds with health benefits.
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