1,082 research outputs found

    Anxiolytic-like effect of Lippia alba essential oil: A randomized, placebo-controlled trial

    Get PDF
    Aim: This study was conducted to examine whether aromatherapy with essential oil of Lippia alba can reduce anxiety levels in a normal population. Methods: The oil was extracted by hycirodistillation for 3 hours using a modified Clevenger-type apparatus and then chemical composition was investigated by a corn. bination of gas chromatography analysis and gas chromatography-mass spectrometry. Moreover, a randomized, double blind, placebo-controlled trial was conducted, where 62 participants were divided into two groups, comprising a control group treated with placebo, and an experimental group (EG) treated with aromatherapy based on Lippia alba essential oil. The anxiety index was evaluated pretest by State-Trait Anxiety Inventory. Measures were taken twice: during pretest and posttest. Results: The chemical analysis showed that carvone was the main component (62,8%), State and trait anxiety scores showed a decrease in the posttest study phase in corn. parison with pretest in the EG (p < 0.005 for state anxiety and p < 0.05 for trait anxiety). Cohen's d score was 1.06 in state anxiety, while it was 0,72 for trait anxiety. The percentages of change showed reductions of anxiety variable ranging between 15.50% for state anxiety and 12.25% for trait anxiety. Conclusion: These results suggest that aromatherapy based on essential oil of Lippia alba may be useful as a means to counteract anxiety

    Hypertension and Histopathology Severity of Non-Alcoholic Fatty Liver Disease Among Adults with Obesity: A Cross-Sectional Study

    Get PDF
    Diego Chambergo-Michilot,1,&ast; Paola K Rodrigo-Gallardo,2 Mariella R Huaman,3,&ast; Angie Z Vasquez-Chavesta,4 Gustavo Salinas-Sedo,5 Carlos J Toro-Huamanchumo6,7,&ast; 1Universidad Científica del Sur, Lima, Peru; 2Hospital Docente Las Mercedes, Chiclayo, Peru; 3Facultad de Medicina Humana, Universidad Nacional Mayor de San Marcos, Lima, Peru; 4Facultad de Medicina Humana, Universidad Católica Santo Toribio de Mogrovejo, Chiclayo, Peru; 5Unidad de Investigación Multidisciplinaria, Clínica Avendaño, Lima, Peru; 6Unidad de Investigación para la Generación y Síntesis de Evidencias en Salud, Universidad San Ignacio de Loyola, Lima, Peru; 7OBEMET Centro de Obesidad y Salud Metabólica, Lima, Peru&ast;These authors contributed equally to this workCorrespondence: Carlos J Toro-Huamanchumo, Universidad San Ignacio de Loyola, Av. la Fontana 550, La Molina, Lima, 15024, Peru, Tel + 51944942888, Email [email protected]: Cardiovascular diseases are responsible for the majority of deaths resulting from non-alcoholic fatty liver disease (NAFLD). NAFLD is associated with hypertension and this is a key predictor of severe liver outcomes and an indicator of nonspecific portal fibrosis.Aim: To assess the association between hypertension and NAFLD severity.Methods: We conducted a secondary analysis of data from Peruvian adults with obesity and NAFLD who attended a Peruvian bariatric center. The severity of NAFLD was assessed using the Fatty Liver Inhibition of Progression algorithm / Steatosis, Activity and Fibrosis score. Hypertension was determined by either being recorded in the medical records or if the patient had a systolic pressure ≥ 140 mmHg or diastolic pressure ≥ 90 mmHg. To evaluate the association of interest, we calculated crude and adjusted prevalence ratios (aPR) using Poisson generalized linear models with logarithmic link function and robust variances. For the multivariable models, we adjusted for age, sex, physical activity and smoking.Results: Our study included 234 participants. The prevalence of hypertension was 19.2%, while the prevalence of severe NAFLD was 46.2%. After adjusting for confounders, the prevalence of hypertension was found to be significantly higher in the severe NAFLD group compared to the non-severe group (aPR = 1.33; 95% CI: 1.03– 1.74). When stratified by the presence of metabolic syndrome (MetS), the association remained significant only in the group without MetS (aPR = 1.80; 95% CI: 1.05– 3.11).Conclusion: We found an association between hypertension and severe NAFLD in adults with obesity, particularly in those without MetS.Keywords: non-alcoholic fatty liver disease, hypertension, obesit

    Nut production in Bertholletia excelsa across a logged forest mosaic: implications for multiple forest use

    Get PDF
    Although many examples of multiple-use forest management may be found in tropical smallholder systems, few studies provide empirical support for the integration of selective timber harvesting with non-timber forest product (NTFP) extraction. Brazil nut (Bertholletia excelsa, Lecythidaceae) is one of the world’s most economically-important NTFP species extracted almost entirely from natural forests across the Amazon Basin. An obligate out-crosser, Brazil nut flowers are pollinated by large-bodied bees, a process resulting in a hard round fruit that takes up to 14 months to mature. As many smallholders turn to the financial security provided by timber, Brazil nut fruits are increasingly being harvested in logged forests. We tested the influence of tree and stand-level covariates (distance to nearest cut stump and local logging intensity) on total nut production at the individual tree level in five recently logged Brazil nut concessions covering about 4000 ha of forest in Madre de Dios, Peru. Our field team accompanied Brazil nut harvesters during the traditional harvest period (January-April 2012 and January-April 2013) in order to collect data on fruit production. Three hundred and ninety-nine (approximately 80%) of the 499 trees included in this study were at least 100 m from the nearest cut stump, suggesting that concessionaires avoid logging near adult Brazil nut trees. Yet even for those trees on the edge of logging gaps, distance to nearest cut stump and local logging intensity did not have a statistically significant influence on Brazil nut production at the applied logging intensities (typically 1–2 timber trees removed per ha). In one concession where at least 4 trees ha-1 were removed, however, the logging intensity covariate resulted in a marginally significant (0.09) P value, highlighting a potential risk for a drop in nut production at higher intensities. While we do not suggest that logging activities should be completely avoided in Brazil nut rich forests, when a buffer zone cannot be observed, low logging intensities should be implemented. The sustainability of this integrated management system will ultimately depend on a complex series of socioeconomic and ecological interactions. Yet we submit that our study provides an important initial step in understanding the compatibility of timber harvesting with a high value NTFP, potentially allowing for diversification of forest use strategies in Amazonian Perù

    Stimulus-dependent maximum entropy models of neural population codes

    Get PDF
    Neural populations encode information about their stimulus in a collective fashion, by joint activity patterns of spiking and silence. A full account of this mapping from stimulus to neural activity is given by the conditional probability distribution over neural codewords given the sensory input. To be able to infer a model for this distribution from large-scale neural recordings, we introduce a stimulus-dependent maximum entropy (SDME) model---a minimal extension of the canonical linear-nonlinear model of a single neuron, to a pairwise-coupled neural population. The model is able to capture the single-cell response properties as well as the correlations in neural spiking due to shared stimulus and due to effective neuron-to-neuron connections. Here we show that in a population of 100 retinal ganglion cells in the salamander retina responding to temporal white-noise stimuli, dependencies between cells play an important encoding role. As a result, the SDME model gives a more accurate account of single cell responses and in particular outperforms uncoupled models in reproducing the distributions of codewords emitted in response to a stimulus. We show how the SDME model, in conjunction with static maximum entropy models of population vocabulary, can be used to estimate information-theoretic quantities like surprise and information transmission in a neural population.Comment: 11 pages, 7 figure

    Light dark matter and ZZ' dark force at colliders

    Full text link
    Light Dark Matter, <10<10 GeV, with sizable direct detection rate is an interesting and less explored scenario. Collider searches can be very powerful, such as through the channel in which a pair of dark matter particle are produced in association with a jet. It is a generic possibility that the mediator of the interaction between DM and the nucleus will also be accessible at the Tevatron and the LHC. Therefore, collider search of the mediator can provide a more comprehensive probe of the dark matter and its interactions. In this article, to demonstrate the complementarity of these two approaches, we focus on the possibility of the mediator being a new U(1)U(1)' gauge boson, which is probably the simplest model which allows a large direct detection cross section for a light dark matter candidate. We combine searches in the monojet+MET channel and dijet resonance search for the mediator. We find that for the mass of ZZ' between 250 GeV and 4 TeV, resonance searches at the colliders provide stronger constraints on this model than the monojet+MET searches.Comment: 23 pages and 14 figure

    Tetrahydrobiopterin modulates ubiquitin conjugation to UBC13/UBE2N and proteasome activity by S-nitrosation

    Get PDF
    Nitric Oxide (NO) is an intracellular signalling mediator, which affects many biological processes via the posttranslational modification of proteins through S-nitrosation. The availability of NO and NOS-derived reactive oxygen species (ROS) from enzymatic uncoupling are determined by the NO synthase cofactor Tetrahydrobiopterin (BH4). Here, using a global proteomics “biotin-switch” approach, we identified components of the ubiquitin-proteasome system to be altered via BH4-dependent NO signalling by protein S-nitrosation. We show S-nitrosation of ubiquitin conjugating E2 enzymes, in particular the catalytic residue C87 of UBC13/UBE2N, leading to impaired polyubiquitylation by interfering with the formation of UBC13~Ub thioester intermediates. In addition, proteasome cleavage activity in cells also seems to be altered by S-nitrosation, correlating with the modification of cysteine residues within the 19S regulatory particle and catalytic subunits of the 20S complex. Our results highlight the widespread impact of BH4 on downstream cellular signalling as evidenced by the effect of a perturbed BH4-dependent NO-Redox balance on critical processes within the ubiquitin-proteasome system (UPS). These studies thereby uncover a novel aspect of NO associated modulation of cellular homeostasis

    Probing natural SUSY from stop pair production at the LHC

    Full text link
    We consider the natural supersymmetry scenario in the framework of the R-parity conserving minimal supersymmetric standard model (called natural MSSM) and examine the observability of stop pair production at the LHC. We first scan the parameters of this scenario under various experimental constraints, including the SM-like Higgs boson mass, the indirect limits from precision electroweak data and B-decays. Then in the allowed parameter space we study the stop pair production at the LHC followed by the stop decay into a top quark plus a lightest neutralino or into a bottom quark plus a chargino. From detailed Monte Carlo simulations of the signals and backgrounds, we find the two decay modes are complementary to each other in probing the stop pair production, and the LHC with s=14\sqrt{s}= 14 TeV and 100 fb1fb^{-1} luminosity is capable of discovering the stop predicted in natural MSSM up to 450 GeV. If no excess events were observed at the LHC, the 95% C.L. exclusion limits of the stop masses can reach around 537 GeV.Comment: 19 pages, 10 figures, version accepted by JHE

    Genome of the Avirulent Human-Infective Trypanosome—Trypanosoma rangeli

    Get PDF
    Background: Trypanosoma rangeli is a hemoflagellate protozoan parasite infecting humans and other wild and domestic mammals across Central and South America. It does not cause human disease, but it can be mistaken for the etiologic agent of Chagas disease, Trypanosoma cruzi. We have sequenced the T. rangeli genome to provide new tools for elucidating the distinct and intriguing biology of this species and the key pathways related to interaction with its arthropod and mammalian hosts.  Methodology/Principal Findings: The T. rangeli haploid genome is ,24 Mb in length, and is the smallest and least repetitive trypanosomatid genome sequenced thus far. This parasite genome has shorter subtelomeric sequences compared to those of T. cruzi and T. brucei; displays intraspecific karyotype variability and lacks minichromosomes. Of the predicted 7,613 protein coding sequences, functional annotations could be determined for 2,415, while 5,043 are hypothetical proteins, some with evidence of protein expression. 7,101 genes (93%) are shared with other trypanosomatids that infect humans. An ortholog of the dcl2 gene involved in the T. brucei RNAi pathway was found in T. rangeli, but the RNAi machinery is non-functional since the other genes in this pathway are pseudogenized. T. rangeli is highly susceptible to oxidative stress, a phenotype that may be explained by a smaller number of anti-oxidant defense enzymes and heatshock proteins.  Conclusions/Significance: Phylogenetic comparison of nuclear and mitochondrial genes indicates that T. rangeli and T. cruzi are equidistant from T. brucei. In addition to revealing new aspects of trypanosome co-evolution within the vertebrate and invertebrate hosts, comparative genomic analysis with pathogenic trypanosomatids provides valuable new information that can be further explored with the aim of developing better diagnostic tools and/or therapeutic targets

    Solving large 0–1 multidimensional knapsack problems by a new simplified binary artificial fish swarm algorithm

    Get PDF
    The artificial fish swarm algorithm has recently been emerged in continuous global optimization. It uses points of a population in space to identify the position of fish in the school. Many real-world optimization problems are described by 0-1 multidimensional knapsack problems that are NP-hard. In the last decades several exact as well as heuristic methods have been proposed for solving these problems. In this paper, a new simpli ed binary version of the artificial fish swarm algorithm is presented, where a point/ fish is represented by a binary string of 0/1 bits. Trial points are created by using crossover and mutation in the different fi sh behavior that are randomly selected by using two user de ned probability values. In order to make the points feasible the presented algorithm uses a random heuristic drop item procedure followed by an add item procedure aiming to increase the profit throughout the adding of more items in the knapsack. A cyclic reinitialization of 50% of the population, and a simple local search that allows the progress of a small percentage of points towards optimality and after that refines the best point in the population greatly improve the quality of the solutions. The presented method is tested on a set of benchmark instances and a comparison with other methods available in literature is shown. The comparison shows that the proposed method can be an alternative method for solving these problems.The authors wish to thank three anonymous referees for their comments and valuable suggestions to improve the paper. The first author acknowledges Ciˆencia 2007 of FCT (Foundation for Science and Technology) Portugal for the fellowship grant C2007-UMINHO-ALGORITMI-04. Financial support from FEDER COMPETE (Operational Programme Thematic Factors of Competitiveness) and FCT under project FCOMP-01-0124-FEDER-022674 is also acknowledged
    corecore