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The aim of this investigation was to study castor, canola, and sesame vegetable oils in order to evaluate their potential use as lubricants in steel mechanical components. For this purpose, densities of each oil were evaluated using the pycnometer method, as well as their dynamic viscosities through a Brookfield DV-II rotational viscometer. Both properties were evaluated at temperatures of 25, 40 and 100 °C. Additionally, viscosity indexes were determined according to ASTM D 2270. These rheological properties were used to estimate the lubrication regime considering parameters of real contact conditions in mechanical components. Friction and wear analyses were carried out to investigate the behaviour of the vegetable oil as lubricants. Such tests were carried out at room temperature on a CSM tribometer with pin-on-disk configuration by using castor, canola and sesame oils as lubricants. AISI 4140 hardened steel against AISI 100Cr6 steel pin was used as a mechanical component. From the rheological study, it was observed that canola and sesame oils behave as dilatant fluids at the evaluated temperatures, while castor oil behaves like a Newtonian fluid at 25 and 40 °C. Castor oil showed the highest density value among oils studied, but it also exhibited the lowest value of viscosity index (271). Contrarily, sesame oil was the least dense, but it exhibited the highest viscosity index (545). On the other hand, the lubrication regime study showed that by using castor oil as a lubricant in the mechanical component (4140/100Cr6), the system worked in a mixed lubrication regime while by using canola and sesame oils the system operated in boundary lubrication conditions. Finally, the kinetic friction coefficients were different for each lubricant obtaining the lowest value with castor oil while the highest value of friction coefficient was exhibited by the sesame oil lubricant.
Social cognition has been associated with functional outcome in patients with first episode psychosis (FEP). Social cognition has also been associated with neurocognition and cognitive reserve. Although cognitive reserve, neurocognitive functioning, social cognition, and functional outcome are related, the direction of their associations is not clear. Therefore, the main aim of this study was to analyze the influence of social cognition as a mediator between cognitive reserve and cognitive domains on functioning in FEP both at baseline and at 2 years.
The sample of the study was composed of 282 FEP patients followed up for 2 years. To analyze whether social cognition mediates the influence of cognitive reserve and cognitive domains on functioning, a path analysis was performed. The statistical significance of any mediation effects was evaluated by bootstrap analysis.
At baseline, as neither cognitive reserve nor the cognitive domains studied were related to functioning, the conditions for mediation were not satisfied. Nevertheless, at 2 years of follow-up, social cognition acted as a mediator between cognitive reserve and functioning. Likewise, social cognition was a mediator between verbal memory and functional outcome. The results of the bootstrap analysis confirmed these significant mediations (95% bootstrapped CI (−10.215 to −0.337) and (−4.731 to −0.605) respectively).
Cognitive reserve and neurocognition are related to functioning, and social cognition mediates in this relationship.
Ovulation is considered an inflammatory, cytokine-mediated event. Cytokines, which are recognized as growth factors with immunoregulatory properties, are involved in many cellular processes at the ovarian level. In this sense, cytokines affect fertility and are involved in the development of different ovarian disorders such as bovine cystic ovarian disease (COD). Because it has been previously demonstrated that ovarian cells represent both sources and targets of cytokines, the aim of this study was to examine the expression of several cytokines, including IL-1β, IL-1RA, IL-1RI, IL-1RII, IL-4 and IL-8, in ovarian follicular structures from cows with spontaneous COD. The protein expression of these cytokines was evaluated by immunohistochemistry. Additionally, IL-1β, IL-4 and IL-8 concentrations in follicular fluid (FF) and serum were determined by enzyme-linked immunosorbent assay (ELISA). In granulosa and theca cells, IL-1RI, IL-1RII, IL-1RA and IL-4 expression levels were higher in cystic follicles than in the control dominant follicles. The serum and FF concentrations of IL-1β and IL-4 showed no differences between groups, whereas IL-8 concentration was detected only in FF of cysts from cows with COD. The FF and serum concentrations of IL-1β and IL-8 showed no significant differences, whereas IL-4 concentration was higher in FF than in serum in both the control and COD groups. These results evidenced an altered expression of cytokines in ovaries of cows with COD that could contribute to the pathogenesis of this disease.
With 30 threatened species (14 categorized as Critically Endangered and 16 as Endangered, sensu IUCN), Coccothrinax (c. 54 species) is the flagship palm genus for conservation in the Caribbean Island Biodiversity Hotspot. Coccothrinax has its centre of taxonomic diversity in these islands, with c. 51 endemic species. We present a conservation framework for the 14 Critically Endangered species, found in Cuba, Haiti or the Dominican Republic. Only two species (C. jimenezii, C. montana) occur in more than one country (Haiti and the Dominican Republic). Immediate threats include oil drilling and nickel mining, intrusion of saline water into soil, urban and agricultural development, low population recruitment, uncontrolled fires, interspecific hybridization, and unsustainable ethnobotanical practices. Coccothrinax bermudezii, C. borhidiana, C. crinita ssp. crinita, C. leonis and C. spissa are not conserved in protected areas. Coccothrinax bermudezii, C. jimenezii, C. leonis and C. nipensis are not part of ex situ collections. Based on results from a conservation project targeting C. jimenezii, we recommend international cooperation between the three range states to implement integrative conservation management plans, plant exploration initiatives, taxonomic revisions, outreach, and fundraising. The ultimate aim of this review is to provide baseline information that will develop conservation synergy among relevant parties working on Coccothrinax conservation in Cuba, Haiti and the Dominican Republic. Such collaborations could also benefit through partnerships with botanists working in other countries.
Polycyclic aromatic hydrocarbons are increasingly widespread pollutants introduced into the environment via oil spillage and incomplete anthropogenic combustion of fossil fuels. In this work, the capacity of stevensite and sepiolite to adsorb phenanthrene (PHE) has been evaluated experimentally by batch testing. Both clay minerals are distributed widely in the Madrid Basin, are of low cost and can be applied with minimal environmental impact. In the context of few previous studies, adsorption isotherms have been developed to understand the adsorption mechanisms and were fitted to the Freundlich and linear models with virtually the same results. Although stevensite showed greater adsorption capacity than sepiolite, the isotherms were constructed for equilibrium concentrations up to 0.8–1.0 mg/L due to the low solubility of PHE in water. When compared to other adsorbents the ability of stevensite to retain PAHs should be examined further in order to add and complement novel functions in reactive barriers.
We report here an observational study on the IR properties of members of the rich clusters of galaxies: Abell 194, Perseus and Hercules. Following the precepts described in previous papers concerning the manifold of the early-type galaxies from IR photometry for the Coma (Recillas-Cruz et al. 1990) and Virgo (Recillas-Cruz et al. 1991) cluster members; interstellar reddening and redshift corrections for Abell 194, Perseus and Hercules were estimated. Interstellar reddening corrections for Abell 194 and Hercules galaxy members were found to be small, except for Perseus cluster galaxies where extinction values are somewhat larger. IR redshift K-corrections were estimated from linear relations with z for (J-H), (H-K) and K (Persson et al. 1979). Corrected magnitudes and colors were then used to construct (J-H) vs. (H-K) diagrams for elliptical and S0 galaxies and color-magnitude diagrams (J-H), (H-K), (J-K), (B-K) and (V-K) vs. K.
A global array of 20 radio observatories was used to measure the three-dimensional position and velocity of the two meteorological balloons that were injected into the equatorial region of the Venus atmosphere by the VEGA spacecraft.
The protein kinase R (PKR, also called EIF2AK2) is an interferon-inducible double-stranded RNA protein kinase with multiple effects on cells that plays an active part in the cellular response to numerous types of stress. PKR has been extensively studied and documented for its relevance as an antiviral agent and a cell growth regulator. Recently, the role of PKR related to metabolism, inflammatory processes, cancer and neurodegenerative diseases has gained interest. In this review, we summarise and discuss the involvement of PKR in several cancer signalling pathways and the dual role that this kinase plays in cancer disease. We emphasise the importance of PKR as a molecular target for both conventional chemotherapeutics and emerging treatments based on novel drugs, and its potential as a biomarker and therapeutic target for several pathologies. Finally, we discuss the impact that the recent knowledge regarding PKR involvement in metabolism has in our understanding of the complex processes of cancer and metabolism pathologies, highlighting the translational research establishing the clinical and therapeutic potential of this pleiotropic kinase.
To study the association of meal patterns and timing with central obesity to identify the best dietary strategies to deal with the increasing obesity prevalence.
A cross-sectional study performed on data from a representative sample of the Spanish population. Height and waist circumference were measured using standardized procedures and waist-to-height ratio (WHtR) was calculated. The sample was divided into those without central obesity (WHtR<0·5) and those with central obesity (WHtR≥0·5).
ANIBES (‘Anthropometric data, macronutrients and micronutrients intake, practice of physical activity, socioeconomic data and lifestyles in Spain’) Study.
Adults aged 18–64 years (n 1655; 798 men and 857 women).
A higher percentage of people ate more than four meals daily in the group without central obesity and those with central obesity more frequently skipped the mid-afternoon snack than those without. Breakfasts containing >25 % of total energy intake and lunches containing >35 % of total energy intake were associated with increased likelihood of central obesity (OR=1·874, 95 % CI 1·019, 3·448; P<0·05 and OR=1·693, 95 % CI 1·264, 2·268; P<0·001, respectively). On the contrary, mid-morning snacks and mid-afternoon snacks containing >15 % of total energy were associated with decreased likelihood of central obesity (OR=0·477, 95 % CI 0·313, 0·727; P<0·001 and OR=0·650, 95 % CI 0·453, 0·932; P<0·05, respectively). The variety of cereals, wholegrain cereals and dairy was higher in the population without central obesity.
Our results suggest that ‘what and when we eat’ should be considered dietary strategies to reduce central obesity.
The objective of this study was to determine whether Staphylococcus aureus chronic intramammary infection (IMI) influences expression of proteins related to regulation of proliferation and apoptosis processes and proliferation/apoptosis index during active involution in bovine mammary gland. Twenty-one Holstein non-pregnant cows in late lactation either uninfected or with chronic naturally acquired S. aureus IMI were included in this study. Cows were slaughtered at 7, 14 and 21 d after cessation of milking and samples for immunohistochemical analysis were taken. Protein expression of Bcl-2, Bax, Fas and active caspase-3 in mammary tissue was significantly affected by chronic S. aureus IMI, all showing increased immunoexpression in S. aureus-infected quarters at all involution stages. The percentage of apoptotic cells was increased by IMI in both mammary parenchyma and stroma, and the percentage of parenchymal and stromal cell proliferation was also increased. The proliferation/apoptosis ratio was significantly increased by IMI only in stromal cells. This imbalance to favour proliferation in S. aureus-infected mammary quarters could be one of the underlying causes that induce aberrant involution with permanence of nonsecretory tissue and increase of stromal components.
Discrete choice models estimated over a large household database, show the impacts of demographics, household behavior, health status, obesity issues and prices on household servings of fruits and vegetables. These impacts are ranked from the most to least effects on daily servings. A major result is the importance of obesity and calorie issues relative to other major demand drivers.
Grammatical constructions are typically partially but not fully productive, which leads to a conundrum for the learner. When can a construction be extended for use with new words and when can it not? The solution suggested here relies on two complementary processes. The first is dynamic categorization: as learners record the statistics of their language, they implicitly categorize the input on the basis of form and function. On the basis of this categorization process, general semantic and phonological constraints on productivity emerge, and productivity is to a large extent determined by the degree to which the category is well attested by similar exemplars. Occasionally, a semantically sensical and phonologically well-formed instance of a well-attested construction is simply not fully acceptable. It is suggested that a process of statistical preemption is at work in these cases: learners avoid using a construction if an alternative formulation has been systematically witnessed instead. The mechanism proposed for statistical preemption is competition-driven learning: when two competitors are activated but one reliably wins, the loser becomes less accessible over time. In this way, the paradox of partial productivity can be resolved.
Overall, autologous bone grafting continues to be the gold standard for the restoration of bone defects while other practices include metallic meshes and plates. These practices are not always suitable particularly when performing reconstructive surgery in the maxillofacial region as the defects tend to be complex in terms of size and shape. These bone defect usually occur due to trauma, infection or a result of oncologic surgeries and therefore the patient requires large amount of bone grafting material .
There is a need for alternative methods such as is artificial bone scaffolds with regenerative medicine approaches in order to enable original tissue regeneration. In order to stimulate tissue regeneration scaffolding materials are required to have certain properties such as biocompatibility, adequate mechanical properties and internal and surface topographical features in order to provide specific biological signals to promote cell attachment and proliferation. Ideally, it would also need to be biodegradable and provide sufficient support for both the particular defect area and cellular ingrowth to degrade over time as new bone tissue is formed . This work analyses the mechanical and chemical properties of Hydroxyapatite (HA) - poly(ethylene glycol) dimethacrylate (PEGDMA) and Hydroxyapatite (HA) - poly(ethylene glycol) diacrylate (PEGDA) based composites used as artificial bone scaffold material with internal structures optimized using finite element analysis (FEA) using Hyperworks OptiStruct (Altair, USA) Topological Optimization and manufactured using commercially available additive manufacturing techniques in order to develop a product that can be introduced directly into the patient. The technique allows implants to be custom made, having the right dimensions and the right mechanical properties.
Testing of the ceramic-hydrogel composite include mechanical testing in compression, tension, bending, impact and hardness while chemical analysis include Fourier Transform Infrared spectroscopy (ATR-FTIR) and Differential Scanning Calorimetry (DSC). Morphology was analyzed using Scanning Electron Microscopy (SEM) and Laser Scanning Confocal Microscopy.
Carbon nanotubes (CNTs) were synthesized by Chemical Vapor Deposition (CVD) from diethyl ether, butanol, hexane and ethyl acetate. A quartz tube with a stainless steel tube catalyst core with 0.019 m diameter and 0.6 m large formed the reactor. To avoid combustion, argon was used as the carrier gas. Time process ranged 30 to 60 min. The range of CNTs synthesis temperature was 680-850 °C for different precursors. Scanning Electron Microscopy micrographs have demonstrated tangled CNTs growth in all samples, thus presenting difficult length measurement. The CNTs diameters from diethyl ether are 45-200 nm, butanol diameter range from 55-230 nm, hexane diameter range is 50-130 nm and ethyl acetate range from 100 to 300 nm. Carbon content for all samples was higher than 93 %, CNTs from butanol showed carbon concentration up to 99%. FTIR, Raman and X-Ray Spectroscopies spectra for all samples demonstrated the characteristics signals present in carbon nanotubes. This research proposes a simple, effective and innovative method to synthesize CNTs by CVD on iron stainless steel catalyst in combination with diethyl ether, ethyl acetate, butanol and hexane as precursors by applying the principles of green chemistry, sustainability and its ease to be scaled.
In this work there was studied the effect of nano-Mg/Al hydrotalcite (NHT) as filler on maleic anhydride grafted linear low density polyethylene (LLDPE-g-MA). NHT was synthesized by the coprecipitation method with a ratio of Mg/Al=6 and nanocomposites were prepared using 1, 3 and 5 %wt of filler via melt-blending.
Morphological and structural analysis of NHT were performed and for nanocomposites, tensile tests and thermal properties were measured. Results showed that filler was well dispersed in the LLDPE matrix, mechanical properties were enhanced in most of the cases and thermal stability improvements were achieved in the nanocomposites.
RNA polymerase III (Pol III) synthesizes small RNA molecules that are essential for cell viability. Accurate initiation of transcription by Pol III requires general transcription factor TFIIIB, which is composed of three subunits: TFIIB-related factor BRF1, TATA-binding protein and BDP1. Here we report the molecular characterization of BRF1 in Trypanosoma brucei (TbBRF1), a parasitic protozoa that shows distinctive transcription characteristics. In silico analysis allowed the detection in TbBRF1 of the three conserved domains located in the N-terminal region of all BRF1 orthologues, namely a zinc ribbon motif and two cyclin repeats. Homology modelling suggested that, similarly to other BRF1 and TFIIB proteins, the TbBRF1 cyclin repeats show the characteristic structure of five α-helices per repeat, connected by a short random-coiled linker. As expected for a transcription factor, TbBRF1 was localized in the nucleus. Knock-down of TbBRF1 by RNA interference (RNAi) showed that this protein is essential for the viability of procyclic forms of T. brucei, since ablation of TbBRF1 led to growth arrest of the parasites. Nuclear run-on and quantitative real-time PCR analyses demonstrated that transcription of all the Pol III-dependent genes analysed was reduced, at different levels, after RNAi induction.
Organic films with a thickness of few nanometers are potentially useful components in many practical and commercial applications such as sensors, detectors, displays and electronic circuit components. In this context, the Langmuir-Blodgett (LB) method is one the most promising techniques for preparing these films.
In this work, we report the synthesis and characterization of three new amphiphilic organometallic compounds with ferrocene units, which consist of one ferrocenyl aminocarbene with the general formula FcC=Cr(CO)5NH(CH2)15CH3, and two ferrocenyl amides with the general formula FcC=MNH(CH2)15CH3 where M = S or Se. These new derivatives have been synthesized to study the influence of long alkyl side chain and the hydrophilic head on the film organization behavior at the air-water interface.
The Langmuir-Blodgett (LB) technique was focused for building ordered nanostructures in molecular assemblies of ferrocenyl derivatives, which are apt to form a stable and transferable monolayer film. The π-A isotherm, hysteresis, Brewster angle microscopy (BAM) and film stability were used to characterize the behavior of a monolayer film at the air-water interface. Z- type LB films were prepared from molecular monolayers which were transferred onto glass substrates. These films were characterized by atomic force microscopy (AFM), UV-Visible spectra and X-ray diffraction (DRX) techniques.