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In this work, green nanotechnology has been applied by using phytochemical compounds as reducing agents from the plant extract of Hydrocotyle ranunuculoides through three modifications of the phytosynthesis method to prepare Fe and Zn nanoparticles, in three different concentration of the metallic solution. In the third modification a MgO support was included to avoid the Fe and Zn NP agglomeration. The nanoparticles size was 5±1 nm, and for the Fe NPs, it was determined with a cubic structure a Fe3O4 composition, and Zn nanoparticles were obtained with a hexagonal structure and Zn° composition. In the third method, MgO nanoparticle, the support appears as Mg0 nanoparticles surrounded by Fe0 and Zn0 nanoparticles. According to the three used methods pathways, the main influence is the modification in the method synthesis. Hybrid nanocomposites provide a means in preventing agglomeration of the NPs and hence avoid coalescence and loss of properties.
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.
The objective of this study was to apply a decision training programme, based on the use of video-feedback and questioning, in real game time, in order to improve decision-making in volleyball attack actions. A three-phase quasi-experimental design was implemented: Phase A (pre-test), Phase B (Intervention) and Phase C (Retention). The sample was made up of 8 female Under-16 volleyball players, who were divided into two groups: experimental group (n = 4) and control group (n = 4). The independent variable was the decision training program, which was applied for 11 weeks in a training context, more specifically in a 6x6 game situation. The player had to analyze the reasons and causes of the decision taken. The dependent variable was decision-making, which was assessed based on systematic observation, using the “Game Performance Assessment Instrument” (GPAI) (Oslin, Mitchell, & Griffin, 1998). Results showed that, after applying the decision training program, the experimental group showed a significantly higher average percentage of successful decisions than the control group F(1, 6) = 11.26; p = .015; η2p = .652; 95% CI [056, 360]. These results highlight the need to complement the training process with cognitive tools such as video-feedback and questioning in order to improve athletes’ decision-making.
This work studied the effect of plasma treatment on the wettability of composite materials constituted of polyethylene glycol (PEG) and polyhydroxybutyrate (PHB) processed through the spin-coating and electrospinning techniques. For this purpose different polymeric solutions of PEG:PHB with proportions of 100:0, 80:20, 50:50, 20:80, and 0:100 were prepared. It found that the hydrophobicity of the as-prepared composite films processed by electrospinning was higher than those processed by spin-coating, using the same proportions of PEG:PHB. The electrospun samples with higher content of PHB (20:80 and 0:100) showed a surface morphology constituted by fibers of 1.7-1.9 μm in size. On the other hand, the electrospun samples processed with a lower content of PHB (100:0, 80:20, 50:50) did not form fibers and exhibited a rough surface. The subsequent plasma treatment with argon plasma of the electrospun samples produced a decrease in the contact angle, even in the samples with surface roughness. These contact angle values were similar to those obtained by spin-coating, or even lower, as in the case of the sample with PEG:PHB content of 20:80 in which the dip-coated film, the as-prepared membrane, and the plasma-treated membrane showed contact angles of 49°, 77.4°, and 0° (superhydrophilic) respectively.
Lumbrinerids are amongst the most abundant and diverse polychaete families in worldwide continental shelves, and have received attention recently through the description of several new species and new occurrences. Herein, a total of four lumbrinerid species are firstly reported in the eastern and southern Spanish continental shelf, extending their biogeographic distribution to the western Mediterranean Sea and increasing up to 25 the number of species known in the Iberian Peninsula coasts. New insights on taxonomy, ecological and biogeographic preferences and an updated taxonomic key for Iberian coasts and surrounding areas are also provided.
Individuals with cocaine and gambling addictions exhibit cognitive flexibility deficits that may underlie persistence of harmful behaviours.
We investigated the neural substrates of cognitive inflexibility in cocaine users v. pathological gamblers, aiming to disambiguate common mechanisms v. cocaine effects.
Eighteen cocaine users, 18 pathological gamblers and 18 controls performed a probabilistic reversal learning task during functional magnetic resonance imaging, and were genotyped for the DRD2/ANKK Taq1A polymorphism.
Cocaine users and pathological gamblers exhibited reduced ventrolateral prefrontal cortex (PFC) signal during reversal shifting. Cocaine users further showed increased dorsomedial PFC (dmPFC) activation relative to pathological gamblers during perseveration, and decreased dorsolateral PFC activation relative to pathological gamblers and controls during shifting. Preliminary genetic findings indicated that cocaine users carrying the DRD2/ANKK Taq1A1+ genotype may derive unique stimulatory effects on shifting-related ventrolateral PFC signal.
Reduced ventrolateral PFC activation during shifting may constitute a common neural marker across gambling and cocaine addictions. Additional cocaine-related effects relate to a wider pattern of task-related dysregulation, reflected in signal abnormalities in dorsolateral and dmPFC.
The effects of thermal treatments on the thermoluminescent (TL) signal of NaCl (ACS reagent) induced by gamma radiation were investigated. Samples of NaCl were thermally treated at 500, 800 and 1000 °C and characterized by X-Ray diffraction and scanning electron microscopy. After their exposure 0.1 to 150 Gy of gamma radiation from a gamma-ray source of 60Co, a TL curve for each temperature of treatment was obtained. We observed a different TL behavior on the irradiated samples as a function of the temperature applied during the thermal treatments. For the sample treated at 500 °C, three peaks centered at 102, 133 and 228 °C were observed. Samples treated at 800 and 1000 °C showed two main peaks at 128 and 220 °C and 136 and 219 °C, respectively; however, the highest TL intensity signal was observed for the sample at 800 °C. All samples showed a linear dependency of the integrated TL intensity from the signal emitted as function of the irradiation time. This is an important advantage because NaCl could be applied as a very low cost thermoluminescent dosimetric material. A comparison between the TL signal induced by gamma radiation in pure and Eu doped NaCl is also reported.
Sapphire is best known for its hardness that makes it ideal for many mechanical and optical applications, but its resistance to radiation damage and its optical properties, combined with metallic nano-particles, make it promising for future opto-electronic and plasmonic devices. In this paper, we present an overview of our work on the fabrication of metallic nano-particles embedded in synthetic sapphire by means of ion implantation, thermal annealing and high energy ion irradiation. We show that we can have control over the amount and size of the nano particles formed inside the matrix by carefully choosing the parameters during the preparation process. Furthermore, we show that anisotropic nano particles can be obtained by an adequate high energy ion irradiation of the originally spherical nano particles. We also have studied the linear and non-linear optical properties of these nano-composites and have confirmed that they are large enough for future applications.
Currently, the research team is systematically studying the oxide compounds present in the ternary system In2O3-TiO2-MgO in order to analyze its thermoluminescent (TL) response. The oxide Mg1.5InTi0.5O4 present in this system was synthesized by a solid state reaction at 1350 °C in air. The X-ray powder diffraction pattern showed a spinel-type structure for this compound. In this work, this spinel, as well as its TL properties when exposed to beta particles, are being reported for the first time. The glow curve is simple and wide with a TL maximum located at 203 °C at 21.33 Gy. The peak shows a shift to lower temperatures and it increases its intensity, as the irradiation dose increases. The lineal behavior was observed between 10.66 to 341 Gy, and no saturation signs were observed. The relative sensitivity variation was 2.7% and standard deviation after ten consecutive irradiation - TL readout cycles was 1 %. The minimum detectable dose was 5.65 Gy for this spinel-type oxide . These results suggest the possible application of Mg1.5InTi0.5O4 in dosimetry.
Recently, a team of archaeologists discovered the existence of the oldest burial in a pyramid known to date in Mesoamerica. The tomb, referred to as Tomb 1, was discovered in Chiapa de Corzo, Chiapas, Mexico. In here, two skeletons were excavated along with a rich offering of green stone pieces, indicating their elite origin. The burial dresses consist of various necklaces, bracelets, belts, and anklets from which some beads were carved in the shape of gourds, monkeys, and alligators. Here we present a full, integrated methodology based on a variety of non-invasive and non-destructive analytical techniques, such as X-ray fluorescence (XRF), Raman, and Fourier Transform infrared (FT-IR) spectroscopy. These techniques are used to characterize and identify the minerals which were found in these burials. This information contributes not only to conservation and restoration purposes, but also gives more insights on the green stone (jadeite and other minerals) trading networks between different cultures in south Mesoamerica in the Pre-Classic period (c.a. 750 – 700 B. C.).
Outstanding information about the material composition and pictorial techniques of the New Spain Colonial painting can be obtained via a full characterization using a set of analytical techniques. Given the cultural importance of this painting, a non-invasive approach is preferred. Moreover, the preparation and use of reference materials using original recipes is necessary for a correct interpretation of the spectroscopic data from historical objects. Here, we present the results obtained via an in-situ Raman spectroscopic analysis of a set of pictorial reference materials, created according to XVI and XVII centuries’ recipes. Several difficulties were encountered, such as the low Raman detection signal, an intrinsic fluorescence of the material, and in some cases even laser-induced degradation. For this reason, the usual molecular Raman analysis was extended to Surface Enhanced Raman Spectroscopy (SERS), which enhances the Raman signal and quenches the fluorescence. It was then applied to the analysis of two wood paintings from the ex-convent San Francisco Tepeyanco, in Tlaxcala.
Human activity and specifically tourism has been increasing in Antarctica over the last few years. Few studies have examined the indirect effects of human visits on Antarctic penguin rookeries. This work aims to study the differences between a highly visited (Hannah Point) and a rarely visited (Devil's Point, Byers Peninsula) gentoo penguin rookery on Livingston Island. Our results suggest that potential indirect effects of human impact are observed in gentoo penguins at Hannah Point, a colony heavily visited by tourists. Penguins at Hannah Point showed a higher presence of heavy metals such as Pb and Ni and a higher number of erythrocytic nuclear abnormalities than penguins at Devil's Point. Immunological parameters showed different results depending on whether we consider the cellular response - the number of lymphocytes being higher in penguins from Hannah Point - or the humoral response - the level of immunoglobulins being higher in penguins from Devil's Point. Measurements of corticosterone levels in feathers and heterophil/lymphocyte (H/L) ratio in blood showed lower levels in the heavily visited rookery than in the rarely visited rookery. Finally, we did not detect Campylobacter jejuni, a bacteria potentially transmitted by humans in either of the populations and we did not find any difference in the prevalence of Campylobacter lari between the populations.
This research aimed to analyze the role of Psychological Well-being factors in young professional tennis players, assigning special attention to their preferred coping strategies and perceived autonomy that specifically contribute to Psychological Well-being. The conceptual framework utilized for this study was Ryff’s Psychological Well-being multidimensional model in order to focus our understanding towards how environment demands of professional sport affect athletes Psychological Well-being. Participants were 155 male professional tennis players with a mean age of 14.61 (SD = 1.86) engaged in South American Tennis Federation tournaments. Instruments utilized were Psychological Well Being Scale EBP, Díaz et al., 2006, Sport Coping Approach Questionnary Spanish version, ACSQ-1 (Kim, Duda, Tomas, & Balaguer, 2003) and Sport Perceived Autonomy Scale, Spanish version (Balaguer, Castillo, & Duda, 2008). Our research revealed that the greater autonomy young athletes perceive while being engaged in professional sport was because of the coping strategies they utilized such as active planning, cognitive restructuring, emotional calmness and seeking of social support. Results confirmed also that the greater perceived autonomy was explaining athletes high levels of Psychological Well-being.
Building upon Deci's and Ryan (1985) Self-determination theory as well as the sportive behavioral correlates of the model of Commitment (Scanlan et al., 1976), this study tries to establish the relationship between motivation and commitment in youth sport. For this purpose 454 young competitive soccer players answered the Sport Motivation Scale (SMS) and the Sport Commitment Questionnaire (SCQ) during the regular season.
The SMS measures the three dimensions of the Motivational continuum (the Amotivation, the Extrinsic Motivation and the Intrinsic Motivation). The SCQ measures the Sportive Commitment and its composing factors such as the Enjoyment, the Alternatives to the sport, and the Social Pressure. Our findings provided a clear pattern of the influence of motivation in sport enjoyment and commitment, outlining the positive contribution of intrinsic and extrinsic motivation to enjoyment and commitment. Amotivation, contributes positively to alternatives to sport and negatively to enjoyment and commitment. It should be noted that extrinsic motivation has a higher contribution to enjoyment whereas intrinsic motivation has a higher contribution to commitment.
In this article we provide sufficient conditions on a space X to verify Ganea conjecture with respect to exterior and proper Lusternik–Schnirelmann category. For this aim we previously develop an exterior version of the Whitehead, cellular approximation, CW-approximation and Blakers–Massey theorems within a homotopy theory of exterior CW-complexes and study their corresponding analogues and consequences in the proper setting.
Researchers, governments and conservation organizations recognize that the long-term integrity of protected areas (PAs) in low-income nations depends upon the support of indigenous and rural communities that live within or around them. Thus, understanding the determinants of residents’ attitudes towards PAs might provide guidance in the design, implementation and evaluation of this strategic form of biodiversity conservation. This paper (1) compares urban and rural residents’ perceptions of the impact of a PA and (2) analyses the association between the perception of economic, social and environmental impacts, and overall attitude towards the PA. Information was collected among urban and rural residents living in the vicinity of the Dandeli Wildlife Sanctuary in the Western Ghats (Karnataka, India). Local residents’ attitudes towards the PA were mainly positive, especially among urban residents. Multivariate analysis showed a positive association between the perception of economic benefits and individual attitudes towards the PA. There was no statistically significant association between attitudes towards the PA and perception of social and environmental impacts. Future research should address whether positive attitudes translate into more sustainable behaviours.
To evaluate the prevalence of undernutrition among community-dwelling elderly people in Spain using the Mini Nutritional Assessment (MNA) and to analyse its distribution according to age, gender and residence region.
Cross-sectional study assessing the nutritional status of elderly persons through both the short form and the full version of the MNA test.
Pharmacy offices across the whole country (Spain) were enrolled to recruit participants.
A total of 22 007 participants (8014 men and 13 993 women), aged ≥65 years, assessed during the last two months of 2005.
According to MNA screening, 4·3 % subjects were classified as undernourished (MNA score <17) and 25·4 % were at risk of undernutrition (MNA score ≥17 to ≤23·5). The MNA short form correlated strongly with the full MNA version (r = 0·85). MNA total score was significantly higher in men than in women (25·4 (sd 3·7) v. 24·6 (sd 3·9); P < 0·001) and lower in the oldest than in the youngest subjects (P < 0·001) in both genders. According to regional distribution, the best nutritional status was found in elderly from the north of Spain excluding the north-west area.
Female gender, older age and living in the south half or north-west of the country were associated with higher rates of undernutrition among community-dwelling elderly persons in Spain.
We establish Whitehead and Ganea characterizations for proper LS-category. We use the embedding of the proper category into the exterior category, and construct in the latter a suitable closed model structure of Strøm type. Then, from the axiomatic LS-category arising from the exterior homotopy category we can recover the corresponding proper LS invariants. Some applications are given.