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In this article, we demonstrate that the combination of elemental and phase mapping is a very powerful tool for characterizing sputtered, binary plutonium alloys.
A specially designed energy-dispersive spectrometer equipped with an automated x-y translational stage was used to measure elemental differences in several disks sputter-coated with binary plutonium alloys. Automated diffractometer scans were obtained from selected areas on the disks by using specially designed sample holders. The elemental differences were then correlated with the phases present and the observed corrosion resistance. The elemental spectra and diffractometer scans were analyzed using a modified version of the SPECPLOT program. This program enables the user to analyze both energy-dispersive elemental data and diffractometer data using a single program.
A sustainable practice for weed control and crop protection is the incorporation of green manures with phytotoxic potential. It is gaining attention as a way to reduce the use of synthetic herbicides in agriculture and so pot experiments and field trials were conducted to explore the possible use of residues of Acacia species to alleviate weed emergence. We assessed, under greenhouse conditions, the herbicidal effect of phytotoxic manures from Acacia dealbata and Acacia longifolia applied to soil at different doses (1.5 and 3% w/w) on maize growth, some accompanying weeds, and the physiological profile of soil microbes. Applied at a higher dose, A. dealbata residues reduced the emergence of dicotyledons in the short-term (P < 0.05) and, after 30 days, there was a decrease in total weed emergence (P < 0.005) and a mild effect on weed composition, while total weed biomass remained unaffected. Regardless of the inclusion of Acacia residues, the physiological profile of the soil bacterial community did not show significant alterations. Additionally, we tested A. dealbata residues as a mulch or a green manure at the field scale. Although the effects of manures were site-dependent and affected monocot and dicot weeds differentially, dicots were more sensitive. The herbicide potential of acacia residues was only evident for dicots at sites with low-weed density in the seed bank. Nevertheless, due to the absence of phytotoxic effects on maize and minor modifications in the functional profile of bacterial communities, residues of acacia could be used as a complementary tool used together with other practices to reduce the reliance on synthetic herbicides in maize-based cropping systems.
Submicron-sized poly(lactide-co-glycolide) nanoparticles (PLGA-NPs) stabilised with bovine serum albumin (BSA) are dual radiolabelled using gamma emitters with different energy spectra incorporated into the core and coating. PLGA core is labelled by encapsulation of 111In-doped iron oxide NPs inside PLGA-NPs during NP preparation, while the BSA coating is labelled by electrophilic substitution using 125I. After intravenous administration into rats, energy-discriminant single-photon emission computerised tomography (SPECT) resolved each radioisotope independently. Imaging revealed different fates for the core and coating, with a fraction of the two radionuclides co-localising in the liver and lungs for long periods of time after administration, suggesting that NPs are stable in these organs. The general methodology reported here represents an excellent alternative for visualising the degradation process of multi-labelled NPs in vivo and can be extended to a wide range of engineered NPs.
El hallazgo de pipas en contextos fúnebres del litoral del Desierto de Atacama hace más de un siglo, ha sido la base para sugerir que los grupos de Pescadores, cazadores y recolectores marinos tuvieron como costumbre fumar durante el período Formativo (1500 a.C-1000 cal d.C). Lo que seguía siendo una incógnita es qué estaban fumando y de dónde provenían las sustancias consumidas. En la búsqueda de dar solución a este problema, presentamos el análisis de los residuos adheridos de cuatro pipas de piedra en forma de T invertida, recuperadas de un cementerio de la costa del Desierto de Atacama al norte de Chile, usando dos metodologías complementarias derivadas de la arqueobotánica y la química. Paralelamente, realizamos un análisis químico sobre cabello humano perteneciente a un individuo asociado a una de las pipas. Se logró identificar, al interior de éstas, la presencia de nicotina y otras sustancias, tales como microrrestos de Nicotiana y de otras especies, además de nicotina, en el cabello muestreado. Finalmente, discutimos estos resultados en función de la disponibilidad defuentes de estos recursos, estrategias de movilidad, relaciones de intercambio y el modo de vida de las poblaciones litorales.
Novel and more conventional boron carbides were combined with n-type silicon to make heterojunction diodes, with neutron capture signal at zero applied bias. The boron carbides were based on the cross linking of closo-1,2-dicarbadodecaborane (ortho-carborane; 1,2-B10C2H12), and cross linking based on the combination of closo-1,2-dicarbadodecaborane (ortho-carborane; 1,2- B10C2H12) and pyridine. In the latter devices, pyridine concentration was varied; samples with a closo-1,2-dicarbadodecaborane (ortho-carborane; 1,2- B10C2H12) to pyridine ratio of 1:1 (BC:Py1) and 1:3 (BC:Py3). The result is a nonvolatile robust p-type semiconductor of boron carbide (B10C2Hx):(C5NHx)y. The I(V) curves for the resulting heterojunction diodes exhibit strong rectification where the normalized reverse bias leakage currents are largely unperturbed with increasing pyridine inclusion. The devices are largely gamma insensitive and yet neutron voltaic properties of these boron carbides is demonstrated. The neutron capture generated pulses from these heterojunction diodes were obtained at zero bias voltage although without the characteristic signatures of complete charge collection from boron neutron capture generated electron-hole pair production. These results, nonetheless, suggest that modifications to boron carbide may result in better neutron voltaic materials with linking groups chosen from family of aromatic compounds that stretch between borazine (B3N3H6) and benzene that point the way to a whole family of future studies that may ultimately lead to boron carbides better suited to low power and low flux neutron detection.
Land-use change can have negative effects on threatened species by modifying their habitat and population dynamics. The habitat of the Endangered Patagonian cypress Fitzroya cupressoides (Mol.) Johnst. (Cupressaceae), a conifer endemic to the temperate forests of southern Chile and Argentina, has been transformed by land-use change and overexploitation. The impact of land-use change on the spatial pattern of F. cupressoides habitat from 1999 to 2011 was evaluated at the landscape level, using satellite images. Additionally, eight 20 × 25 m plots were established in four populations to assess their status. In each plot the density of F. cupressoides and the species richness of the associated plant communities were recorded and analysed, together with spatial patterns at the population and community levels. The loss of potential F. cupressoides habitat was 46% from 1999 to 2011 (38–100% for the four populations). The density of F. cupressoides was lowest in smaller habitat patches, where the number of plant species was higher and the matrix dominated by anthropogenic land-use. Land-use change was associated with a loss of potential habitat for F. cupressoides, and differences in the spatial patterns of habitat influenced the composition of remaining populations and communities. A landscape approach is recommended as a conservation planning strategy for F. cupressoides.
The Consideration of Future Consequences Scale (CFC-S) is a measure of the extent to which individuals reflect and are influenced by the immediate as well as by the distant outcomes of current behavior. It´s composed by 12 items, grouped into two subscales (future and immediate). This study aims to explore the factor structure, psychometric properties and construct validity of the Portuguese version of the CFC-S in 5 samples, composed by 527 participants with ages between 13 and 71. A 2 factor structure has been found through Confirmatory Factor Analysis among several tested models. Item 5 has been eliminated in order to achieve better fit indices (χ2df = 3.88, CFI = .90, GFI = .95, RMSEA = .07) and improve internal consistency. Both CFC subscales presented strong correlations with several psychological phenomena (Sensation Seeking, Self-Esteem, Temporal Extension and Time Perspective) and main effects among groups of age and criminal record (for CFC-I, p < .001, for CFC-F, p < .001). These results allow us to support CFC as an efficient psychological evaluation instrument and as an important metric for individual differences in the study of temporal orientation.
Hsp90 is a widely distributed and highly conserved molecular chaperone that is ubiquitously expressed throughout nature, being one of the most abundant proteins within non-stressed cells. This chaperone is up-regulated following stressful events and has been involved in many cellular processes. In Toxoplasma gondii, Hsp90 could be linked with many essential processes of the parasite such as host cell invasion, replication and tachyzoite-bradyzoite interconversion. A Protein-Protein Interaction (PPI) network approach of TgHsp90 has allowed inferring how these processes may be altered. In addition, data mining of T. gondii phosphoproteome and acetylome has allowed the generation of the phosphorylation and acetylation map of TgHsp90. This review focuses on the potential roles of TgHsp90 in parasite biology and the analysis of experimental data in comparison with its counterparts in yeast and humans.
The widespread loss and degradation of native forests is now recognised as a major environmental issue, even a crisis (Spilsbury 2010). During the first decade of the twenty-first century, global forest area declined by around 13 million ha yr−1 (FAO 2010). However, such estimates based on national statistics are uncertain (Grainger 2008); Hansen et al. (2010) report a substantially higher annual forest loss of approximately 20 million ha yr−1 for 2000–2005, based on analysis of satellite imagery.
The Food and Agriculture Organization (FAO 2010) also report that during the decade 2000–2010, the area of undisturbed primary forest declined by an estimated 4.2 million ha yr−1 (or 0.4% annually), largely because of the introduction of selective logging and other forms of human disturbance. Accurate data on the extent of forest degradation at the global scale are difficult to obtain (Gibbs et al. 2007), but an indication of its impact is provided by a recent estimate of the amount of carbon stored in forest vegetation. Over the period 1990–2005, global forest carbon stocks declined, in percentage terms, by almost double the decline in forest area (UNEP 2007). Given the current emphasis of global forest policy initiatives on both deforestation and forest degradation, particularly in the context of the UN REDD+ programme, there is an urgent need not only for improved forest monitoring (Baker et al. 2010; Gibbs et al. 2007; Grainger 2008; Sasaki & Putz 2009), but for a deeper understanding of the processes responsible for forest degradation and their potential impacts on forest biodiversity.
Triatoma virus (TrV) is a small, non-enveloped virus that has a+ssRNA genome and is currently classified under the Cripavirus genus of the Dicistroviridae family. TrV infects haematophagous triatomine insects (Hemiptera: Reduviidae), which are vectors of American trypanosomosis (Chagas disease). TrV can be transmitted through the horizontal faecal–oral route, and causes either deleterious sublethal effects or even the death of laboratory insect colonies. Various species of triatomines from different regions of Latin America are currently being reared in research laboratories, with little or no awareness of the presence of TrV; therefore, any biological conclusion drawn from experiments on insects infected with this virus is inherently affected by the side effects of its infection. In this study, we developed a mathematical model to estimate the sample size required for detecting a TrV infection. We applied this model to screen the infection in the faeces of triatomines belonging to insectaries from 13 Latin American countries, carrying out the identification of TrV by using RT-PCR. TrV was detected in samples coming from Argentina, which is where the virus was first isolated from Triatoma infestans (Hemiptera: Reduviidae) several years ago. Interestingly, several colonies from Brazil were also found infected with the virus. This positive result widens the TrV's host range to a total of 14 triatomine species. Our findings suggest that many triatomine species distributed over a large region of South America may be naturally infected with TrV.
Bisphosphonates have been proposed as pharmacological agents against parasite and cancer cell growth. The effect of these compounds on helminthic cell viability and acellular compartment morphology, however, has not yet been studied. The effects of different types of bisphosphonates, namely etidronate (EHDP), pamidronate (APD), alendronate (ABP), ibandronate (IB) and olpadronate (OPD), and their interaction with amiloride, 1,25-dihydroxycholecalciferol (D3) and proline were evaluated on a cell line derived from bovine Echinococcus granulousus protoscoleces (EGPE) that forms cystic colonies in agarose. The EGPE cell line allowed testing the effect of bisphosphonates alone and in association with other compounds that could modulate calcium apposition/deposition, and were useful in measuring the impact of these compounds on cell growth, cystic colony formation and calcium storage. Decreased cell growth and cystic colony formation were found with EHDP, IB and OPD, and increased calcium storage with EHDP only. Calcium storage in EGPE cells appeared to be sensitive to the effect of amiloride, D3 and proline. Proline decreased calcium storage and increased colony formation. Changes in calcium storage may be associated with degenerative changes of the cysts, as shown in the in vitro colony model and linked to an adenosine triphosphate (ATP) decrease. In conclusion, bisphosphonates could be suitable tempering drugs to treat cestode infections.
Samples were collected from 10 stations distributed through three sectors in Guanabara Bay during two consecutive years, in order to determine factors that influence the spatial pattern of molluscs and to describe the structure and composition of this community in a eutrophic estuarine system on the Brazilian coast. Although only one species, the gastropod Heleobia australis, comprised 77% of mollusc abundance, 59 species were identified in the bay. In addition to H. australis, three other species were dominant: the gastropod Anachis isabellei and the bivalves Americuna besnardi and Ervilia concentrica. The mollusc communities were significantly influenced by the spatial gradient; the outermost sector has marine conditions, and the other sectors are typically estuarine, leading to differences in the composition and abundance of molluscs. The outermost sector showed the highest diversity, which gradually decreased towards the innermost sector where the dominance of a few opportunistic species is favoured by highly organic mud sediments. Sediment type was strongly correlated with mollusc occurrence in the bay. Guanabara Bay showed two indicator species: the bivalve E. concentrica of the outer sector, and the gastropod H. australis of the intermediate sector. Our results suggest that benthic molluscs in Guanabara Bay show characteristics related to levels of environmental impact. A monitoring programme based on this community is needed to evaluate the effects of human impacts on this community and to monitor changes in its biodiversity in Guanabara Bay.
Musical scores constitute a key element in the development of expertise in musicians from western tonal traditions, since they act as a mediator between the performer and the music itself. Our aim was to study the role of musical scores in instrumental performance practice by analysing the process of learning a new piece of music, as well as the frequency of activities related to that score, taking account of situations when studying alone and with a teacher. Sixteen flute students at two different education levels from conservatoires in Madrid participated in an individual semi-structured interview and completed a rating-scale questionnaire. Categorical analysis from interview data revealed differences between levels in relation to the activities they stated that they engaged in when learning new pieces. Results from the questionnaires showed that although students at both levels worked on playing the musical score correctly, higher-level students seemed to pay special attention to artistic issues. The findings are discussed in relation to previous research, as well as their implications for education.
In his 1551 Travagliata invenzione, the Italian mathematician Niccolò Tartaglia described a device for raising sunken ships. Despite his claim of originality, his contemporary Girolamo Cardano had described a similar method in his famous work De subtilitate, which was published a year before. A comparison between these methods reveals the uniqueness of Tartaglia's approach, for he combines an explicit defence of the horror vacui principle with an implicit negation of rarefaction. In this article I show the complexities of this conception and stress the importance of keeping the personal argument between both authors in mind when interpreting their descriptions of wreck-salvage operations.
The triode sputtering technique and a “split-target” arrangement were used to produce metastable crystalline and amorphous phases in the Cu-W, Mo-Cu, Ag-Fe, Ag-Cu, Pu-Ta and Pu-V systems. These systems all exhibit liquid and solid immiscibility and have positive heats of mixing and atomic radii that differ by at least 10%. The sputtered coatings, whose thickness varied between 25 and 200 microns, were formed at deposition rates between 35 and 200 Å/s. They were characterized using x-ray diffraction, TEM, microprobe, microhardness, and DSC techniques. The observed amorphous and metastable solid solution phases are discussed in terms of predicated heats of formation for these phases using Miedema's thermodynamic approximations  that include chemical, elastic, and structural contributions. Differences in compositional ranges observed by high rate sputter deposition compared to other vapor deposition techniques (e.g., coevaporation) appeared to arise as a result of processes that occur during deposition or immediately following deposition.
To evaluate the feasibility of diet mediterranisation, in a food-at-work context, and its consequence on metabolic syndrome in a mid-age unselected healthy male population group.
One-year longitudinal intervention study. Physical exercise was not modified.
All workers of the Santiago division of ‘Maestranza Diesel’, a metal-mechanic company servicing the mining industry, were invited to participate.
Initially, 145 workers of a total of 171, of average age 39 years, accepted to participate (sixteen women and 129 men). A subgroup of ninety-six men fully completed the controls programmed for the intervention study. Losses from the original group correspond to missing one control (sixteen), leaving the company (eleven) or blood sampling discomfort (six). The women and sixteen male workers, hired post study initiation, did participate but were excluded from this 12-month analysis.
Diet mediterranisation was successful, reflected in the daily food consumption at the canteen and the evolution of the Mediterranean diet score (MDS) from 4·8 ± 1·4 to 7·4 ± 1·5 (limits 0–14). Some metabolic syndrome components showed statistically significant improvement and also statistically significant correlation with the MDS: waist circumference, HDL-cholesterol, systolic and diastolic blood pressure. After 12 months, the reversion rate for metabolic syndrome was 48 % (12/23) with an incidence rate of 4·1 % for new cases (3/73). In total, metabolic syndrome decreased from 24·0 % to 15·6 % (23/96 to 15/96) (P = 0·029).
Diet mediterranisation is feasible in a food-at-work intervention, affecting lunch consumption at the workers canteen and overall consumption evaluated with MDS, together with a significant reduction in metabolic syndrome.