Two semi-automated computational approaches for spectroscopic analysis of stellar photospheres: detailed characterization at high resolution and abundance determination at medium resolution

We report on two distinct computational approaches to self-consistently measure photospheric properties of large samples of stars. Both procedures consist of a set of several semi-integrated tasks based on shell and Python scripts, which efficiently run either our own codes or open source software commonly adopted by the astronomical community. One approach aims to derive the main stellar photospheric parameters and abundances of a few elements by analysing high-resolution spectra from a given public library homogeneously constructed. The other one is applied to recover the abundance of a single element in stars with known photospheric parameters by using mid-resolution spectra from another open homogeneous database and calibrating derived abundances. Both semi-automated computational approaches provide homogeneity and objectivity to every step of the process and represent a fast way to reach partial and final results as well as to estimate measurement errors, making possible to systematically evaluate and improve the distinct steps.Comment: 7 pages, 4 figures, conference paper (I Workshop of Computacao Cientifica em Astronomia, Brazil, 2011) to appear in the Journal of Computational Interdisciplinary Sciences - JCI

Mind the social feedback : effects of tDCS applied to the left DLPFC on psychophysiological responses during the anticipation and reception of social evaluations

The left dorsolateral prefrontal cortex (lDLPFC) is implicated in anticipatory (i.e. during anticipation of emotional stimuli) and online (i.e. during confrontation with emotional stimuli) emotion regulatory processes. However, research that investigates the causal role of the lDLPFC in these processes is lacking. In this study, 74 participants received active or sham transcranial direct current stimulation (tDCS) over the lDLPFC. Participants were told strangers evaluated them. These (rigged) social evaluations were presented, and in 50% of the trials, participants could anticipate the valence (positive or negative) of the upcoming social feedback. Pupil dilation (a marker of cognitive resource allocation) and skin conductance responses (a marker of arousal) were measured. The results indicate that active (compared to sham) tDCS reduced arousal during the confrontation with anticipated feedback but only marginally during the confrontation with unanticipated feedback. When participants were given the opportunity to anticipate the social feedback, tDCS reduced arousal, irrespective of whether one was anticipating or being confronted with the anticipated feedback. Moreover, tDCS reduced cognitive resource allocation during anticipation, which was associated with resource allocation increases during the subsequent confrontation. Altogether, results suggest that the lDLPFC is causally implicated in the interplay between anticipatory and online emotion regulatory processes

Continuous measurement of nitrate concentration in a highly event-responsive agricultural catchment in south-west of France: is the gain of information useful?

A nitrate sensor has been set up to measure every 10 min the nitrate signal in a stream draining a small agricultural catchment dominated by fertilized crops during a 2-year study period (2006–2008) in the south-west of France. An in situ sampling protocol using automatic sampler to monitor flood events have been used to assume a point-to-point calibration of the sensor values. The nitrate concentration exhibits nonsystematic concentration and dilution effects during flood events. We demonstrate that the calibrated nitrate sensor signal gathered from the outlet is considered to be a continuous signal using the Nyquist–Shannon sampling theorem. The objectives of this study are to quantify the errors generated by a typical infrequent sampling protocol and to design appropriate sampling strategy according to the sampling objectives. Nitrate concentration signal and flow data are numerically sampled to simulate common sampling frequencies. The total fluxes calculated from the simulated samples are compared with the reference value computed on the continuous signal. Uncertainties are increasing as sampling intervals increase; the method that is not using continuous discharge to compute nitrate fluxes bring larger uncertainty. The dispersion and bias computed for each sampling interval are used to evaluate the uncertainty during each hydrological period. High underestimation is made during flood periods when high-concentration period is overlooked. On the contrary, high sampling frequencies (from 3 h to 1 day) lead to a systematic overestimation (bias around 3%): highest concentrations are overweighted by the interpolation of the concentration in such case. The in situ sampling protocol generates less than 1% of load estimation error and sample highest concentration peaks. We consider useful such newly emerging field technologies to assess short-term variations of water quality parameters, to minimize the number of samples to be analysed and to assess the quality state of the stream at any time

Effects of organic versus conventional farming on different chemical soil parameters in Estonia

A five-year experiment results, have shown that fertilizer amendments are needed for preserving the nutrient balance in the soil. A combination of cattle and green manure, crop rotation and other organic farming practices, with chemical fertilizer amendments could suppose a sustainable solution for maintaining a correct nutrient balance in the soil in long term, better than both farming systems, conventional and organic, by separate

Seeking equity and justice in urban freight: where to look?

Urban freight systems embed and reflect spatial inequities in cities and imbalanced power structures within transport decision-making. These concerns are principal domains of “transportation justice” (TJ) and “mobility justice” (MJ) scholarship that have emerged in the past decade. However, little research exists situating urban freight within these prevailing frameworks, which leaves urban freight research on socio-environmental equity and justice ill-defined, especially compared to passenger or personal mobility discussions. Through the lens that derives from TJ and MJ’s critical dialogue, this study synthesises urban freight literature’s engagement with equity and justice. Namely, the review evaluates: How do researchers identify equitable distributions of urban freight’s costs and benefits? At what scale do researchers evaluate urban freight inequities? And who does research consider entitled to urban freight equity and how are they involved in urban freight governance? The findings help inform researchers who seek to reimagine urban freight management strategies within broader equity and justice discourse

Talviste vahekultuuride haljasväetiseks kasvatamise mõju vihmaussidele

Vihmaussidel on oluline roll mullaviljakuse kujunemisel. Nende elutegevuse tagajärjel paraneb orgaanilise aine mineralisatsioon ja lagunemine. Vihmausse peetakse keskkonna hindamise oluliseks vahendiks tänu pidevale kontaktile mullaga, mulla vee ja selles lahustunud sooladega (Ivask, 1996). Vihmaussikoosluste ja struktuuri põhjal saab teha järeldusi põllumajandusliku tegevuse mõjust muldadele. Liikide arv, biomass ja koosluse ökoloogiline struktuur on põllumajanduslikes muldades üks olulisemaid parameetreid, määramaks mulla saastatust ja olukorda (Paoletti, 1999). Vihmausside aktiivsus ja biomass sõltub oluliselt majandamisviisist ning seeläbi mullaharimisest, orgaaniliste või mineraalsete väetiste lisamisest ning mulda viidava orgaanilise aine kogusest. Väetamine üldjuhul soodustab vihmausside levikut, kuna väetiste lisamine mulda suurendab nende toiduvaru ning loob soodsamad tingimused vihmausside arenguks. Liblikõieliste lisamine külvikorda mõjutab arvukust positiivselt (Jordan jt., 2004) ning monokultuuride kasvatamine võib olla levikut piiravaks teguriks (Ventiš., 2011). Vihmausside arvukust, massi ja mitmekesisust mõjutavaid tegureid on palju uuritud. Enamasti on peamiseks uurimisalaks mullaharimise (Peigne jt., 2009), orgaaniliste ja mineraalsete väetiste (Jordan jt., 2004) ning mahe- ja tavaviljeluse mõju vihmausside arvukusele ja biomassile (Ivask jt., 2007). Talviste vahekultuuride mõju vihmaussikooslusele on senini vähe uuritud. Antud uurimistöö eesmärgiks oli selgitada vahekultuuride haljasväetiseks kasvatamise mõju vihmausside arvukusele, massile ja liigilisele koosseisule maheviljeluslikus külvikorras

Modelling of trace metal transfer in a large river under different hydrological conditions (the Garonne River in southwest France)

The modelling of trace metals (TM) in rivers is highly dependent on hydrodynamics, the transport of suspended particulate matter (SPM) and the partition between dissolved and particulate phases. A mechanistic, dynamic and distributed model is proposed that describes the fate of trace metals in rivers with respect to hydrodynamics, river morphology, erosion-sedimentation processes and sorption–desorption processes in order to identify the most meaningful parameters and processes involved at the reach scale of a large river.The hydraulic model is based on the 1-D Saint Venant equation integrating real transects to incorporate the river's morphology. The transport model of dissolved species and suspended sediments is based on advection–dispersion equations and is coupled to the one-dimensional transport with in flowand storage (OTIS) model, which takes transient storage zones into account. The erosion and sedimentation model uses Partheniades equations. Finally, the transfer of trace metals is simulated using two parameters,namely the partition coefficient(Kd)and the concentration of TM in the eroded material. The model was tested on the middle course of the Garonne River,southwest France,over an 80km section under two contrasting hydrological conditions (80m3 s-1 and 800m3 s-1) based on measurements (hydrology, suspended sediments, particulate and dissolved metals fractions) taken at 13 sampling stations and tributaries. The hydrodynamic model was calibrated with discharge data for the hydraulic model,tracer experiments for the dissolved transport model and SPM data for the erosion-sedimentation model. The TM model was tested on two trace metals: arsenic and lead. Arsenic was chosen for its large dissolved fraction, while lead was chosen for its very important particulate fraction, thus providing contrasting elements. The modelling of TM requires all four processes to be simulated simultaneously. The presented model requires the calibration of ten parameters divided in four submodels during two hydrological conditions(lowand high flow). All parameters could be explained by the physical properties of the case study, suggesting that the model could be applied to other case studies. The strategy of using different datasets under different hydrological conditions highlights: (a) the importance of transient storage in the study case, (b) a detailed description of the erosion and sedimentation processes of SPM, and (c) the importance of TM eroded from the sediment as a secondary delayed source for surface water

Understanding nitrogen transfer dynamics in a small agricultural catchment: Comparison of a distributed (TNT2) and a semi distributed (SWAT) modeling approaches

The coupling of an hydrological and a crop model is an efficient approach to study the impact of the interactions between agricultural practices and catchment physical characteristics on stream water quality. We analyzed the consequences of using different modeling approaches of the processes controlling the nitrogen (N) dynamics in a small agricultural catchment monitored for 15 years. Two agro-hydrological models were applied: the fully distributed model TNT2 and the semi-distributed SWAT model. Using the same input dataset, the calibration process aimed at reproducing the same annual water and N balance in both models, to compare the spatial and temporal variability of the main N processes. The models simulated different seasonal cycles for soil N. The main processes involved were N mineralization and denitrification. TNT2 simulated marked seasonal variations with a net increase of mineralization in autumn, after a transient immobilization phase due to the burying of the straw with low C:N ratio. SWAT predicted a steady humus mineralization with an increase when straws are buried and a decrease afterwards. Denitrification was mainly occuring in autumn in TNT2 because of the dynamics of N availability in soil and of the climatic and hydrological conditions. SWAT predicts denitrification in winter, when mineral N is available in soil layers. The spatial distribution of these two processes was different as well: less denitrification in bottom land and close to ditches in TNT2, as a result of N transfer dynamics. Both models simulate correctly global trend and inter-annual variability of N losses in small agricultural catchment when a sufficient amount data is available for calibration. However, N processes and their spatial interactions are simulated very differently, in particular soil mineralization and denitrification. The use of such tools for prediction must be considered with care, unless a proper calibration and validation of the different N processes is carried out

Impacts of social networking sites on patient care in the emergency department

The use of Facebook is ubiquitous among both patients and physicians. Often Facebook intrudes into medical practice, thereby highlighting its potential to be either a positive or negative factor in a patient\u27s medical care. Despite being a “hot topic” in the medical literature, very few real world examples exist of physicians actually using information obtained from Facebook to reach a diagnosis or otherwise affect patient care. We present a case involving a 13-year-old girl who posted photographs and captions on Facebook demonstrating suicidal ideation. The patient\u27s parents were alerted to the girl\u27s statements in her Facebook profile and brought her to the emergency department. The girl\u27s statements and photographs, as reported by her parents, were used by an emergency physician to make a diagnosis of suicidal risk and to disposition of the patient to an inpatient psychiatric ward. We discuss the potential diagnostic utility of information posted on Facebook and briefly discuss the ethical questions surrounding this situation