1,414 research outputs found

    Caracterización química de los volátiles de Tagetes nelsonii

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    Species of the genus Tagetes (Astereceae) have shown important medicinal and biological properties.  Many Tagetes species are native from Mexico, however, there are few studies on their volatiles. The objective of the present study is to characterize the volatiles of Tagetes nelsonni Greenm commonly known as “Chik chawa”, which is a plant used in some regions of Chiapas State, Mexico for medicinal purposes.  Our work was focused to extract and to identify the T. nelsonii volatiles using Solid Phase Microextraction (SPME) and Gas Chromatography-Mass Espectrometry (GC-MS) respectively. The compounds identified are a mixture of terpenes.  The major volatile components are (E)-β-tagetone (43-9%) and dihydrotagetone (20.7%), followed by trans-β-ocimene, eucaliptol, limonene and β-cubebene. Tagetes nelsonni contains fragant compounds as α and β-pinene, trans-β-ocimene, limonene, linalool, (E) and (Z)-tagetones, dihydrotagetone and cis and trans-tagetenone with potential to be used for cosmetic, pharmaceutical purposes and to help to control insect pest of plant problems.Especies del género Tagetes (Asteraceae) han mostrado tener propiedades medicinales y biológicas muy importantes. Muchas especies de Tagetes son nativas de México, sin embargo, existen pocos estudios sobre la caracterización de sus volátiles.  El objetivo del presente trabajo es caracterizar químicamente los volátiles de Tagetes nelsonii comúnmente conocida como “Chik chawa”, la cual es una planta utilizada en algunas regiones del estado de Chiapas, México para fines medicinales. La pregunta es que si las hojas de T. nelsonii son ricas en compuestos fragantes con propiedades medicinales. Los volátiles de T. nelsonii fueron extraídos e identificados utilizando las técnicas de Microextracción en Fase Sólida y Cromatografía de gases acoplada a Espectrometría de masas (GC-MS) respectivamente.  Los compuestos emitidos por T.  nelsonii son una mezcla de compuestos terpénicos. Los compuestos mayoritarios son (E)-tagetona (43-9%) y dihidrotagetona (20.7%), seguidos por trans-β-ocimeno, eucaliptol, limoneno y β-cubebeno. T. nelsonii contiene compuestos fragantes como, α y β-pineno, trans-β-ocimeno, limoneno, linalool, tagetonas, dihidrotagetona y tagetenonas con potencial para ser usados como cosméticos y farmacéuticos y para resolver problemas de plagas de insectos de las plantas como repelentes. &nbsp

    Generation of Bioelectricity Using Molasses as Fuel in Microbial Fuel Cells

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    The large amount of molasses that are generated in sugar-processing companies are not always redistributed for commercialization in by-products. Because of this, the present research uses these wastes as fuel in low-cost, lab-scale, single-chamber microbial fuel cells. Zinc and copper electrodes were used as electrodes and 100 mL of molasse in the chamber as fuel, managing to generate current and voltage peaks of 1.73 ± 0.13 mA and 0.953 ± 0.142 V. In monitoring the conductivity of the substrate, a maximum peak of 111.156 ± 8.45 mS/cm was observed, and a slightly acidic pH was observed throughout the monitoring. It was possible to obtain a power density of 5.45 ± 0.31 W/cm2 for a current density of 308.06 mA/cm2, while the yeast count showed a logarithmic curve throughout the monitoring. Finally, the molecular technique identified 100% of the special C. boidinii present in the anodic electrode. This research will give great benefits to sugar companies because they will be able to generate electricity using the molasses that cannot generate by-products

    Detección del virus de la lengua azul en ovinos por RT- PCR en tiempo real en diferentes sistemas de producción en San Martín, Perú

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    The present study aimed to determine the prevalence of Bluetongue Virus (BTV) in sheep, by the real-time Reverse Transcription-polymerase chain reaction (RT-PCR) technique. Three hundred sixty-six sheep from the ten provinces of the Peru region were evaluated. The methodology used was the collection of blood samples from the jugular vein of the sheep, then the process of extraction and purification of RNA was carried out with the QIAmp® kit, then the reverse transcription to obtain the cDNA, and finally perform the real-time RT-PCR, for which the SuperScript III platinium One-step qRT-PCR kit was used, with the primers and probes being directed to segment 10 of the NS3 gene of BTV. The results of the real-time RT-PCR test revealed two positive sheep with a value of cycle threshold (Ct) of 35.21 and 35.57, with a prevalence of 0.54 % of BTV-positive sheep in the extensive production system, with environmental conditions that favor the development of the Culicoides vector. It is concluded that, by means of the real-time RT-PCR technique, the presence of BTV in this region of Peru is confirmed, which makes future studies necessary to determine the detection of other potential serotypes of BTV in the Peruvian Amazon in order to improve the control strategies of the disease.El presente estudio tuvo como objetivo determinar la prevalencia del Virus de la Lengua Azul (VLA) en ovinos, por la técnica reacción en cadena de la polimerasa con Transcripción Reversa (RT- PCR) en tiempo real. Se evaluaron 366 ovinos procedentes de las diez provincias de la región del Perú. La metodología empleada fue la toma de muestras sanguínea de la vena yugular del ovino, seguidamente se realizó el proceso de extracción y purificación de ARN con el kit QIAmp®, luego la transcripción reversa para obtener el ADNc, y finalmente realizar la RT- PCR en tiempo real, para lo cual se utilizó el kit SuperScript III platinium One- step qRT–PCR, siendo los iniciadores y sondas dirigidos al segmento 10 del gen NS3 del VLA. Los resultados de la prueba de RT-PCR en tiempo real revelaron dos ovinos positivos con valor de ciclo umbral (Ct) de 35.21 y 35.57, siendo la prevalencia de 0.54 % de ovinos positivos a VLA en sistema de crianza extensiva, con las condiciones del ambiente que favorecen el desarrollo del vector Culicoide. Se concluye que mediante la técnica RT-PCR en tiempo real, se confirma la presencia del VLA en esta región del Perú, lo que hace necesario futuros estudios para determinar la detección de otros serotipos potenciales de VLA en la Amazonia peruana, con la finalidad de mejorar las estrategias de control de la enfermedad

    Elimination of Onchocerca volvulus

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    In Latin America, onchocerciasis is targeted for elimination by 2012 through twice-yearly mass treatment of the eligible population with ivermectin. In Guatemala, two of the four historical endemic foci have demonstrated elimination of transmission, following World Health Organization guidelines. Using established guidelines ophthalmological, serological, and entomological evaluations were conducted in 2007-8 to determine the transmission status of onchocerciasis in the Huehuetenango focus. The prevalence of Onchocerca volvulus microfilariae in the anterior segment of the eye in 365 residents was 0% (95% confidence interval [CI] 0–0.8%), the prevalence of infection of O. volvulus in Simulium ochraceum among 8252 flies collected between November 2007 and April 2008 was 0% (95% CI 0–0.02%), and the prevalence of antibodies to a recombinant O. volvulus antigen in 3118 school age children was 0% (95% CI 0–0.1%). These results showed transmission interruption; thus, in 2009 mass treatment was halted and posttreatment surveillance began. To verify for potential recrudescence an entomological evaluation (from December 2010 to April 2011) was conducted during the 2nd and 3rd year of posttreatment surveillance. A total of 4587 S. ochraceum were collected, and the prevalence of infection of O. volvulus was 0% (95% CI 0–0.04%). Transmission of onchocerciasis in the Huehuetenango focus has been eliminated

    Successful Interruption of Transmission of Onchocerca volvulus in the Escuintla-Guatemala Focus, Guatemala

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    Brought to the Americas from Africa by the slave trade, onchocerciasis is present in six countries in Latin America. The disease is caused by a round worm and is transmitted to humans by the bite of an infected black fly. Once in a human, the adult worms produce larvae that circulate through the body, causing itching or even blindness. Ivermectin, a drug that kills the larvae, is delivered by public health authorities in countries where the disease is present. If the larvae are killed, then the disease cannot be transmitted to more people. People living in the Escuintla-Guatemala focus, a region in Guatemala where the disease was common, have been taking ivermectin for many years. The Ministry of Health of Guatemala believes that onchocerciasis is no longer being transmitted in the area. To prove that there is no more transmission of the disease, the authors examined the eyes of residents of the area to see if they could find any evidence of the worms. They also conducted analyses of blood in school children to see if they had ever been exposed to the worm, and they caught thousands of black flies and tested them to see if they were infected. These evaluations found no evidence of transmission of the disease in the Escuintla-Guatemala focus. As a result, local public health authorities can stop giving ivermectin and invest their human resources in other important diseases

    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

    Pervasive gaps in Amazonian ecological research

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    Azimuthal anisotropy of charged jet production in root s(NN)=2.76 TeV Pb-Pb collisions

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    We present measurements of the azimuthal dependence of charged jet production in central and semi-central root s(NN) = 2.76 TeV Pb-Pb collisions with respect to the second harmonic event plane, quantified as nu(ch)(2) (jet). Jet finding is performed employing the anti-k(T) algorithm with a resolution parameter R = 0.2 using charged tracks from the ALICE tracking system. The contribution of the azimuthal anisotropy of the underlying event is taken into account event-by-event. The remaining (statistical) region-to-region fluctuations are removed on an ensemble basis by unfolding the jet spectra for different event plane orientations independently. Significant non-zero nu(ch)(2) (jet) is observed in semi-central collisions (30-50% centrality) for 20 <p(T)(ch) (jet) <90 GeV/c. The azimuthal dependence of the charged jet production is similar to the dependence observed for jets comprising both charged and neutral fragments, and compatible with measurements of the nu(2) of single charged particles at high p(T). Good agreement between the data and predictions from JEWEL, an event generator simulating parton shower evolution in the presence of a dense QCD medium, is found in semi-central collisions. (C) 2015 CERN for the benefit of the ALICE Collaboration. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).Peer reviewe

    Search for lepton-flavour-violating decays of the Higgs and Z bosons with the ATLAS detector

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    Direct searches for lepton flavour violation in decays of the Higgs and Z bosons with the ATLAS detector at the LHC are presented. The following three decays are considered: H→eτ, H→μτ, and Z→μτ. The searches are based on the data sample of proton–proton collisions collected by the ATLAS detector corresponding to an integrated luminosity of 20.3 fb−1 at a centre-of-mass energy of s√=8 TeV. No significant excess is observed, and upper limits on the lepton-flavour-violating branching ratios are set at the 95 % confidence level: Br (H→eτ)<1.04%, Br (H→μτ)<1.43%, and Br (Z→μτ)<1.69×10−5

    Multi-messenger observations of a binary neutron star merger

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    On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta
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