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We report experimental evidence of the destabilization of a 3D torus obtained when a small subharmonic perturbation is added to a 2D torus characteristic of a driven relaxation oscillator. The Poincaré sections indicate that the torus breakup is sensitive to the phase difference between the main driving frequency and its first subharmonic perturbing component. The observed transition confirms the Newhouse, Ruelle and Takens quasiperiodic transition to chaos on a 3D torus. Numerical results on a sinusoidally perturbed circle map mirror the experimental results and confirm the key role of the phase difference in the transition between distinct dynamical regimes. [ABSTRACT FROM AUTHOR]

Copyright of Prospectiva (1692-8261) is the property of Universidad Autonoma del Caribe and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The sustainability and efficiency of ecotourism regarding biodiversity conservation are under constant scrutiny and often dismissed based on negative effects arising from other types of nature-based tourism. Our study assess the impacts of infrastructure, human activity, and environmental factors on medium-large ground terrestrial species within the Lapa Rios Ecolodge Nature Reserve; results indicate that restoration, preservation, and conservation efforts are responsible for the wide range of species found within their reserve, including increased abundance of highly threatened rodents and ground birds. There is no indication that visitation or tour activities have negative impacts on wildlife; instead, the Ecolodge effectively created a 'human shield' that weakens threats to wildlife arising from hunting, logging, and gold mining. This shield effect ripples across the Osa Peninsula through the socio-economic benefits provided by ecotourism. Our results support a conservation model incorporating private reserves and parks to sustain biodiversity. [ABSTRACT FROM AUTHOR]

Congenital toxoplasmosis (CT) is a zoonosis resulting from the fetal transmission of the obligate intracellular parasite, T. gondii, transplacentally in pregnant women usually in the first trimester of pregnancy. This research consisted in the review of indexed articles made in the Ecuador in the period between the years 2012 and 2017 with prevalence studies of the aforementioned pathology. The purpose of this collection was to determine the current situation of this disease in the Ecuadorian territory and, in addition, to recognize the risk factors involved, affected age groups, signs and symptoms, diagnosis and prevalence of the infection. Among the risk factors were the consumption of raw or undercooked meat, contact with feces of young cats and climatic conditions that stimulate the spread of oocysts, among others. Most affected ages by this disease fluctuate between 20 and 30 years. In 90% of the cases, the disease is asymptomatic or it may present adenopathies, maculo papular erythema, hepatosplenomegaly and other general signs such as fever, malaise, headache and myalgias. According to studies conducted with specific populations, it was established that the causative agent remains latent in first-trimester pregnant women from the provinces of Pichincha (71.4% of 140 pregnant women), Guayas (73% of 5683) and El Oro (16% of 250). The results of this research evidenced missing information in Ecuador, finding few and isolated studies regarding to this pathology. Therefore, it is concluded that an updated research should be conducted in order to elucidate the true epidemiological situation of congenital toxoplasmosis in Ecuador. [ABSTRACT FROM AUTHOR]

The article offers information about Non-meningothelial meningeal tumors with meningioangiomatosis. Topics discussed include perivascular spread of meningothelial and fibroblastic cells results Meningioangiomatosis; talks about biopsy of parieto-occipital mass reveals cellular neoplasm involving the leptomeninges; and mentions morphological and immunohistochemical sarcoma, shows features of rhabdomyosarcoma.

Copyright of Revista Técnica Energía is the property of Centro Nacional de Control de Energia CENACE and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Técnica Energía is the property of Centro Nacional de Control de Energia CENACE and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We discuss the phase control technique consisting of an applied square pulsed periodic perturbation. We explore the effect of such perturbations to the different terms of the Duffing oscillator. We find that the effect depends sensitively on how the perturbation is applied, indeed, it is specially effective when it modulates the cubic and the linear term and uneffective when applied to the driving term. Our results highlight the highly nontrivial role of the phase when applying a second periodic perturbation to a chaotic system. [ABSTRACT FROM AUTHOR]

On the north coast of present-day Peru, between the Andes and the Pacific Ocean, approximately between 100 and 600 ad, the Moche civilization prospered. The Moche were very sophisticated artisans and metal smiths, so that they are considered the finest producers of jewels and artifacts of the region. Their metalworking ability was impressively demonstrated by the excavations of the tomb of the 'Lady of Cao' (dated around third-fourth century ad) discovered by Regulo Franco in 2005. Impressive is the beauty of the artifacts, and also the variety of metallurgical solutions, demonstrated by not only the presence of objects composed of gold and silver alloys but also of gilded copper, gilded silver, and tumbaga, a poor gold Cu-Au alloy subject to depletion gilding. About 100 metal artifacts from the tomb of the Lady of Cao, never before analyzed, were studied by using various portable equipments based on following non-destructive and non-invasive methods: energy-dispersive X-ray fluorescence with completely portable equipments;, transmission of monenergetic X-rays;, radiographic techniques; and, optical microscopy., Gold objects and gold areas of nose decorations are characterized by approximately the same composition, that is, Au = (79.5 ± 2.5) %, Ag = (16 ± 3) %, and Cu = (4.5 ± 1.5) %, while silver objects and silver areas of the same nose decorations show completely erratic results, and a systematic high gold concentration. Many gilded copper and tumbaga artifacts were identified and analyzed. Further, soldering gold-silver was specifically studied by radiographs. Additional measurements are needed, particularly because of the suspect that depletion gilding was systematically employed also in the case of some nose decorations. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Copyright of Revista Técnica Energía is the property of Centro Nacional de Control de Energia CENACE and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background High mobility group box 1 ( HMGB1) is a small nuclear protein with two functions. In the nucleus, it helps to wrap DNA around nucleosomes. When secreted, it recruits inflammatory cells and induces cytokine production. Before HMGB1 is secreted from inflammatory cells, it relocates to the cytoplasm, which partially or totally depletes cell nuclei of HMGB1. We previously showed that cells lacking HMGB1 contain 20% fewer nucleosomes and 30% more RNA transcripts levels genome-wide. Objective We hypothesized that the depletion of nuclear HMGB1 plays a role in inflammation that can enhance or complement the role of extracellular HMGB1. Methods We analysed the transcriptional profile of wild-type and Hmgb1−/− mouse embryonic fibroblasts ( MEFs) as a proxy for cells that have lost HMGB1 from their nuclei. We explored the transcriptome of wild-type and Hmgb1−/− macrophages differentiated in the presence of granulocyte-macrophage colony-stimulating factor, before and after exposure to LPS/ IFN-γ. In the same cells, histones and nuclear HMGB1 were quantified. Results We found that Hmgb1−/− MEFs show a transcriptional profile associated with stress and inflammation responses. Moreover, wild-type macrophages that have secreted HMGB1 because of LPS/ IFN-γ exposure rapidly reduce their histone content as much as cells that genetically lack HMGB1. Importantly, unstimulated Hmgb1−/− macrophages activate transcriptional pathways associated with cell migration and chemotaxis. Conclusions We suggest that nucleosome loss is an early event that facilitates transcriptional responses of macrophages to inflammation, particularly chemotaxis. HMGB1's dual roles in the nucleus and in the extracellular space appear to be complementary. [ABSTRACT FROM AUTHOR]

Copyright of Spanish Journal of Rural Development is the property of Spanish Journal of Rural Development and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Superficies y Vacío is the property of Sociedad Mexicana de Ciencia y Tecnologia de Superficies y Materiales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Detecting determinism in univariate and multivariate time series is difficult if the underlying process is nonlinear, and the noise level is high. In a previous paper, the authors proposed a method based on observable ordinal patterns. This method exploits the robustness of admissible ordinal patterns against observational noise, and the super-exponential growth of forbidden ordinal patterns with the length of the patterns. The new method compared favorably to the Brock-Dechert-Scheinkman independence test when applied to time series projected from the Hénon attractor and contaminated with Gaussian noise of different variances. In this paper, we extend this comparison to higher fractal dimensions by using noisy orbits on the attractors of the Lorenz map, and the time-delayed Hénon map. Finally, we make an analysis that enlightens the robustness of admissible ordinal patterns in the presence of observational noise. [ABSTRACT FROM AUTHOR]

Tropical dry forests may be among the world's most threatened ecosystems, but few studies have objectively quantified their status and threats. This study analysed Venezuelan dry forests at multiple scales, assessing status, present threats and the policy context shaping their future. Historical and current dry forest cover at both national and local scales were contrasted, and a set of quantitative risk assessment criteria applied. While dry forests were vulnerable nationally, in northern-central locations they were endangered. Clearing for cattle ranching and for intensive and subsistence agriculture were the principal factors driving dry forest loss at the national scale, while at a local level, urbanization and fire seemed to be the primary threats. The analysis emphasized the separation of risk assessment from the very different task of establishing conservation priorities; high risk areas may not necessarily be the highest priority for investment, and policy makers may become explicitly aware of the spatial scale at which their policies are implemented, as well as how these policies may affect or be affected by the status of ecosystems beyond their area of influence. The main challenge to future dry forest conservation is a paucity of explicit policies for management and use. However, scientifically-based management can support positive dry forest policies in many ways, including identifying locations and protocols for ecological restoration, maintaining seed banks, quantifying baseline conditions, and monitoring genetic diversity and other indicators. [ABSTRACT FROM PUBLISHER]

Introduction: Palliative sedation (PS) is the subject of ethical and legal debates worldwide. Statistics of its utilization are available in developed countries; however, in Latin America, these data are scarcely known. The purpose of this research was to determine the practices and attitudes of palliativists in Latin America towards PS.Materials and Methods: Data was collected during the Latin American Congress on Palliative Care in Isla Margarita, Venezuela. A total of 89 professionals participated in this survey.Results: It was found that the use of PS was positively associated with being a physician and being members of a palliative care (PC) group. On the other hand, it was found that being a psychologist and identifying barriers toward PS limited its utilization.Discussion: The findings of this study support the need to establish clinical guidelines for its utilization and to educate other specialists on end-of-life care approaches, and the need to develop PC programs in acute care hospitals in Latin America. [ABSTRACT FROM AUTHOR]

We have proposed an adaptive procedure in order to estimate unknown parameters of a numerical model of a chaotic CO2 laser, which is observed through a time series that represents the output intensity of the laser. To do that, we consider a coupled system with the same functional form and adjustable parameters. The salient feature of the proposed technique is that accurate parameter estimation and identical synchronization can be jointly achieved by adaptively adjusting the desired parameters of the coupled system. [ABSTRACT FROM AUTHOR]