104 research outputs found

    Pooled Time Series Modeling Reveals Smoking Habit Memory Pattern

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    Smoking is a habit that is hard to break because nicotine is highly addictive and smoking behavior is strongly linked to multiple daily activities and routines. Here, we explored the effect of gender, age, day of the week, and previous smoking on the number of cigarettes smoked on any given day. Data consisted of daily records of the number of cigarettes participants smoked over an average period of 84 days. The sample included smokers (36 men and 26 women), aged between 18 and 26 years, who smoked at least five cigarettes a day and had smoked for at least 2 years. A panel data analysis was performed by way of multilevel pooled time series modeling. Smoking on any given day was a function of the number of cigarettes smoked on the previous day, and 2, 7, 14, 21, 28, 35, 42, 49, and 56 days previously, and the day of the week. Neither gender nor age influenced this pattern, with no multilevel effects being detected, thus the behavior of all participants fitted the same smoking model. These novel findings show empirically that smoking behavior is governed by firmly established temporal dependence patterns and inform temporal parameters for the rational design of smoking cessation programs

    Enhancing the context-aware FOREX market simulation using a parallel elastic network model

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    [EN] Foreign exchange (FOREX) market is a decentralized global marketplace in which different participants, such as international banks, companies or investors, can buy, sell, exchange and speculate on currencies. This market is considered to be the largest financial market in the world in terms of trading volume. Indeed, the just-in-time price prediction for a currency pair exchange rate (e.g., EUR/USD) provides valuable information for companies and investors as they can take different actions to improve their business. The trading volume in the FOREX market is huge, disperses, in continuous operations (24 h except weekends), and the context significantly affects the exchange rates. This paper introduces a context-aware algorithm to model the behavior of the FOREX Market, called parallel elastic network model (PENM). This algorithm is inspired by natural procedures like the behavior of macromolecules in dissolution. The main results of this work include the possibility to represent the market evolution of up to 21 currency pair, being all connected, thus emulating the real-world FOREX market behavior. Moreover, because the computational needs required are highly costly as the number of currency pairs increases, a hybrid parallelization using several shared memory and message passing algorithms studied on distributed cluster is evaluated to achieve a high-throughput algorithm that answers the real-time constraints of the FOREX market. The PENM is also compared with a vector autoregressive (VAR) model using both a classical statistical measure and a profitability measure. Specifically, the results indicate that PENM outperforms VAR models in terms of quality, achieving up to 930xspeed-up factor compared to traditional R codes using in this field.This work was jointly supported by the Fundación Séneca (Agencia Regional de Ciencia y Tecnología, Región de Murcia) under Grant 20813/PI/18 and by the Spanish MEC and European Commission FEDER under Grants TIN2016-78799-P and TIN2016-80565-R (AEI/FEDER, UE).Contreras, AV.; Llanes, A.; Herrera, FJ.; Navarro, S.; López-Espin, JJ.; Cecilia-Canales, JM. (2020). Enhancing the context-aware FOREX market simulation using a parallel elastic network model. The Journal of Supercomputing. 76(3):2022-2038. https://doi.org/10.1007/s11227-019-02838-1S20222038763Bahrepour M, Akbarzadeh-T MR, Yaghoobi M, Naghibi-S MB (2011) An adaptive ordered fuzzy time series with application to FOREX. Expert Syst Appl 38(1):475–485Bank for International Settlements. https://www.bis.org/ . 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J Chem Theory Comput 9(12):5618–5628Hanssens DM, Parsons LJ, Schultz RL (2003) Market response models: econometric and time series analysis, vol 12. Springer, New YorkKamruzzaman J, Sarker RA (2003) Forecasting of currency exchange rates using ANN: a case study. In: Proceedings of the 2003 International Conference on Neural Networks and Signal Processing, 2003, vol 1. IEEE, pp 793–797Kamruzzaman J, Sarker RA, Ahmad I (2003) SVM based models for predicting foreign currency exchange rates. In: Third IEEE International Conference on Data Mining, 2003. ICDM 2003, IEEE, pp. 557–560Karplus M, McCammon JA (2002) Molecular dynamics simulations of biomolecules. Nat Struct Mol Biol 9(9):646–652Kleen A (2015) Intel PMU profiling tools. https://github.com/andikleen/pmu-tools/tree/d70840ba . Accessed 15 Mar 2019Kuo RJ, Chen C, Hwang Y (2001) An intelligent stock trading decision support system through integration of genetic algorithm based fuzzy neural network and artificial neural network. Fuzzy Sets Syst 118(1):21–45LeBaron B, Arthur WB, Palmer R (1999) Time series properties of an artificial stock market. J Econ Dyn Control 23(9):1487–1516Li Q, Chen Y, Wang J, Chen Y, Chen H (2017) Web media and stock markets: a survey and future directions from a big data perspective. IEEE Trans Knowl Data Eng 30:381–399Luetkepohl H (2009) Econometric analysis with vector autoregressive models. In: Belsley DA, Kontoghiorghes EJ (eds) Handbook of computational econometrics. Wiley, New York, pp 281–319Makovskỳ P (2014) Modern approaches to efficient market hypothesis of FOREX—the central European case. Proc Econ Finance 14:397–406Meade N (2002) A comparison of the accuracy of short term foreign exchange forecasting methods. Int J Forecast 18(1):67–83Meese RA, Rogoff K (1983) Empirical exchange rate models of the seventies: do they fit out of sample? J Int Econ 14(1–2):3–24Mockus J, Raudys A (2010) On the efficient-market hypothesis and stock exchange game model. Expert Syst Appl 37(8):5673–5681Nassirtoussi AK, Aghabozorgi S, Wah TY, Ngo DCL (2014) Text mining for market prediction: a systematic review. Expert Syst Appl 41(16):7653–7670Neely C, Weller P, Dittmar R (1997) Is technical analysis in the foreign exchange market profitable? A genetic programming approach. J Financial Quant Anal 32(4):405–426Pincak R (2013) The string prediction models as invariants of time series in the FOREX market. Phys A: Stat Mech Appl 392(24):6414–6426Samuelson PA (2016) Proof that properly anticipated prices fluctuate randomly. In: The World Scientific Handbook of Futures Markets, pp 25–38Sarantis N, Stewart C (1995) Structural, VAR and BVAR models of exchange rate determination: a comparison of their forecasting performance. J Forecast 14(3):201–215Schmidhuber J (2015) Deep learning in neural networks: an overview. Neural Netw 61:85–117Sims CA (1980) Macroeconomics and reality. Econ: J Econ Soc. 48:1–48Ţiţan AG (2015) The efficient market hypothesis: review of specialized literature and empirical research. Proc Econ Finance 32:442–449Yao J, Tan CL (2000) A case study on using neural networks to perform technical forecasting of FOREX. Neurocomputing 34(1):79–9

    Deciphering Main Climate and Edaphic Components Driving Oat Adaptation to Mediterranean Environments

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    Oat, Avena sativa, is an important crop traditionally grown in cool-temperate regions. However, its cultivated area in the Mediterranean rim steadily increased during the last 20 years due to its good adaptation to a wide range of soils. Nevertheless, under Mediterranean cultivation conditions, oats have to face high temperatures and drought episodes that reduce its yield as compared with northern regions. Therefore, oat crop needs to be improved for adaptation to Mediterranean environments. In this work, we investigated the influence of climatic and edaphic variables on a collection of 709 Mediterranean landraces and cultivars growing under Mediterranean conditions. We performed genotype–environment interaction analysis using heritability-adjusted genotype plus genotype–environment biplot analyses to determine the best performing accessions. Further, their local adaptation to different environmental variables and the partial contribution of climate and edaphic factors to the different agronomic traits was determined through canonical correspondence, redundancy analysis, and variation partitioning. Here, we show that northern bred elite cultivars were not among the best performing accessions in Mediterranean environments, with several landraces outyielding these. While all the best performing cultivars had early flowering, this was not the case for all the best performing landraces, which showed different patterns of adaption to Mediterranean agroclimatic conditions. Thus, higher yielding landraces showed adaptation to moderate to low levels of rain during pre- and postflowering periods and moderate to high temperature and radiation during post-flowering period. This analysis also highlights landraces adapted to more extreme environmental conditions. The study allowed the selection of oat genotypes adapted to different climate and edaphic factors, reducing undesired effect of environmental variables on agronomic traits and highlights the usefulness of variation partitioning for selecting genotypes adapted to specific climate and edaphic conditionsThis work was supported by the grant PID2019-104518RBI00 funded by MCIN/AEI/10.13039/501100011033. FC and LMG-S are holder of a FPI fellowship (BES-2014-071044) and (BES-2017-080152), respectively, from the Spanish Ministry of Economy and Competitiveness. GM-B is holder of a Junta de Andalucia grant for Doctors [DOC_00394]. We thank CRF and USDA for supplying the seed

    Intensive longitudinal modelling predicts diurnal activity of salivary alpha-amylase

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    Salivary alpha-amylase (sAA) activity has been widely used in psychological and medical research as a surrogate marker of sympathetic nervous system activation, though its utility remains controversial. The aim of this work was to compare alternative intensive longitudinal models of sAA data: (a) a traditional model, where sAA is a function of hour (hr) and hr squared (sAAj,t = f(hr, hr2 ), and (b) an autoregressive model, where values of sAA are a function of previous values (sAAj,t = f(sAA j,t-1, sAA j,t-2, . . ., sAA j,t-p). Nineteen normal subjects (9 males and 10 females) participated in the experiments and measurements were performed every hr between 9:00 and 21:00 hr. Thus, a total of 13 measurements were obtained per participant. The Napierian logarithm of the enzymatic activity of sAA was analysed. Data showed that a second-order autoregressive (AR(2)) model was more parsimonious and fitted better than the traditional multilevel quadratic model. Therefore, sAA follows a process whereby, to forecast its value at any given time, sAA values one and two hr prior to that time (sAA j,t = f(SAAj,t-1, SAAj,t-2) are most predictive, thus indicating that sAA has its own inertia, with a “memory” of the two previous hr. These novel findings highlight the relevance of intensive longitudinal models in physiological data analysis and have considerable implications for physiological and biobehavioural research involving sAA measurements and other stress-related biomarkers

    The relict population of Pinna nobilis in the Mar Menor is facing an uncertain future

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    Pinna nobilis is undergoing one of the most dramatic events suffered by an endangered species. An emerging disease has relegated its populations to coastal lagoons or estuaries with salinities beyond the 36.5–39.7 psu range. The Mar Menor is one of two such locations on the Spanish coastline. Poor environmental conditions and eutrophication and anoxia events, that became critical in 2016, 2019 and 2021, have reduced its population in >99 %. In this work, the spatial distribution of the species within the lagoon and the factors determining its survival along the successive crises of eutrophication are studied using a two-stage (presence/absence estimation and density modelling) Species Distribution Model. A potential area of 200.97 ha and an average density of 1.05 ind.100 m2 is estimated for 2020. The viability of the Mar Menor population depends on management actions designed both for the species and to improve the lagoon environmental state.This research was supported by the EU LIFE Programme Project “Protection and restoration of Pinna nobilis populations as a response to the catastrophic pandemic started in 2016” (LIFE PINNARCA) [grant number LIFE20 NAT/ES/001265] and the Biodiversity Foundation of the Ministry for Ecological Transition and the Demographic Challenge Project RECUPERA PINNA [grant number IRTA1-21T]. This research was supported by the Dirección General del Mar Menor, Consejería de Agua, Agricultura, Ganadería, Pesca y Medio Ambiente (CARM), Project “Proyecto para la cría ex situ de Pinna nobilis y creación del Banco de Especies protegidas y singulares del Mar Menor”

    El consumo de fitosteroles ¿un arma de doble filo?

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    Phytosterols are plant sterols structurally similar to cholesterol. The most common phytosterols are ß-sitosterol, campesterol and stigmasterol. They are present in many foods but mainly in nuts and vegetable oils. They compete with cholesterol absorption decreasing the cardiovascular risk. Recent studies have associated the intake of 0.63-3g/day of phytosterols with lowering serum cholesterol and LDL-cholesterol levels. The same decrease has been observed in apolipoprotein B. These results suggest that dietary phytosterols are useful for protection against cardiovascular disease. Because of this they have been incorporated in relatively high quantities into spreads and margarines. However, negative effects have also been reported. Among them, a significant decrease in the absorption of several lypophilic antioxidant compounds such as carotenoids and tocopherols, which may counterbalance the protective cardiovascular effect of phytosterols. In this paper the results of several selected studies relating phytosterol consumption and plasma levels of lipids, lipoproteins and antioxidants are reviewed. More studies are needed to establish if it is necessary to supplement with such antioxidant compounds the diet of people consuming phytosterols for therapeutical purposes.Los fitosteroles son esteroles de plantas con una estructura similar a la del colesterol. Los fitosteroles más frecuentes son: ß-sitosterol, campesterol y estigmasterol. Están ampliamente distribuidos en los alimentos, siendo las nueces y aceites vegetales fuentes importantes de estas sustancias. Los fitosteroles compiten en el organismo en la absorción del colesterol por lo que se han propuesto como protectores del riesgo cardiovascular. Consumos diarios de 0,63-3g/día de fitosteroles parecen disminuir tanto el colesterol plasmático como los niveles de LDL-colesterol, conjuntamente con los niveles de apolipoproteína B. Con el propósito de aprovechar dichas acciones, se han incluido en distintos productos, como margarinas y untables. Sin embargo, no todo son beneficios y su consumo también produce efectos negativos. Así, disminuyen significativamente la absorción de ciertos compuestos lipofílicos antioxidantes, como carotenoides y tocoferoles, implicados a su vez en la protección cardiovascular. En esta minirrevisión se comentan los resultados de algunos estudios que relacionan consumo de fitosteroles y concentración en plasma de lípidos, lipoproteínas y algunos antioxidantes. Se precisan estudios que diluciden si es necesario incrementar el consumo de tales compuestos antioxidantes en poblaciones que reciben suplementos de fitosteroles con fines terapéuticos

    Population genomics of Mediterranean oat (A. sativa) reveals high genetic diversity and three loci for heading date

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    KEY MESSAGE: Genomic analysis of Mediterranean oats reveals high genetic diversity and three loci for adaptation to this environment. This information together with phenotyping and passport data, gathered in an interactive map, will be a vital resource for oat genetic improvement. ABSTRACT: During the twentieth century, oat landraces have increasingly been replaced by modern cultivars, resulting in loss of genetic diversity. However, landraces have considerable potential to improve disease and abiotic stress tolerance and may outperform cultivars under low input systems. In this work, we assembled a panel of 669 oat landraces from Mediterranean rim and 40 cultivated oat varieties and performed the first large-scale population genetic analysis of both red and white oat types of Mediterranean origin. We created a public database associated with an interactive map to visualize information for each accession. The oat collection was genotyped with 17,288 single-nucleotide polymorphism (SNP) loci to evaluate population structure and linkage disequilibrium (LD); to perform a genome-wide association study (GWAs) for heading date, a key character closely correlated with performance in this drought-prone area. Population genetic analysis using both structure and PCA distinguished two main groups composed of the red and white oats, respectively. The white oat group was further divided into two subgroups. LD decay was slower within white lines in linkage groups Mrg01, 02, 04, 12, 13, 15, 23, 33, whereas it was slower within red lines in Mrg03, 05, 06, 11, 21, 24, and 28. Association analysis showed several significant markers associated with heading date on linkage group Mrg13 in white oats and on Mrg01 and Mrg08 in red oats. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00122-021-03805-2

    Fatty Acid Profile Changes During Gradual Soil Water Depletion in Oats Suggests a Role for Jasmonates in Coping With Drought

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    Although often investigated within the context of plant growth and development and/or seed composition, plant lipids have roles in responses to environment. To dissect changes in lipid and fatty acid composition linked to drought tolerance responses in oats, we performed a detailed profiling of ( > 90) different lipids classes during a time course of water stress. We used two oat cultivars, Flega and Patones previously characterized as susceptible and tolerant to drought, respectively. Significant differences in lipid classes (mono, di and triacylglycerols; [respectively MAG, DAG, and TAG] and free fatty acids [FFA]) and in their fatty acid (FA) composition was observed between cultivars upon drought stress. In Flega there was an increase of saturated FAs, in particular 16:0 in the DAG and TAG fractions. This led to significant lower values of the double bond index and polyunsaturated/saturated ratio in Flega compared with Patones. By contrast, Patones was characterized by the early induction of signaling- related lipids and fatty acids, such as DAGs and linolenic acid. Since the latter is a precursor of jasmonates, we investigated further changes of this signaling molecule. Targeted measurements of jasmonic acid (JA) and Ile-JA indicated early increases in the concentrations of these molecules in Patones upon drought stress whereas no changes were observed in Flega. Altogether, these data suggest a role for jasmonates and specific fatty acids in different lipid classes in coping with drought stress in oat

    Métricas alimentarias de dos condrictios meso-bentónicos en aguas de Chile central: Food metrics of two meso-benthic chondrichthyans in waters of central Chile

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    Little has been studied of the food metrics of most chondrichthyans, which provide baseline information for the assessment of fishing status to guide the development of ecosystem-based management plans. Therefore, the main goal of this study was to approach the isotopic niche of Dipturus chilensis and Callorhinchus callorynchus in Valparaíso (central Chile). The main findings showed that C. callorynchus presented a narrow ellipse (E= 0.79; RC= 4.14; θ= 1.39), meanwhile D. chilensis, presented an ellipse with greater extension (E= 0.95; RC= 8,23; θ= -0.11), therefore a wide isotopic niche

    Sistema multifunción programable para uso en agricultura.

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    Número de publicación: 2 338 628 Número de solicitud: 201030144El sistema permite, respecto al resto de programadores de riego del mercado, que se puede utilizar un mismo hardware para realizar multitud de configuraciones diferentes con tan solo cambiar el software, todo ello con un bajo coste. Para ello, incorpora una interfaz software/ hardware consistente en una tarjeta de adquisición de datos DAQ (1) y una placa de adaptación sobre la que se sitúa un convertidor de potencia asociada a las distintas entradas y salidas digitales del sistema, contando con medios de operación manual, paralelos a los medios de operación automáticos constituidos por un software de programación asociado a un ordenador o PC al que se conecta la citada tarjeta de datos, de manera que éste puede integrarse en dicho equipo o constituir un elemento externo y conectado al mismo, indistintamente.Universidad Politécnica de CartagenaUniversidad Miguel Hernández de Elch
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