Prediction of Complications After Pancreaticoduodenectomy: Validation of a Postoperative Complication Score.

OBJECTIVES: Pancreatic surgery remains associated with important morbidity. Efforts are most commonly concentrated on decreasing postoperative morbidity, but early detection of patients at risk could be another valuable strategy. A simple prognostic score has recently been published. This study aimed to validate this score and discuss possible clinical implications. METHODS: From 2000 to 2012, 245 patients underwent a pancreaticoduodenectomy. Complications were graded according to the Dindo-Clavien Classification. The Braga score is based on American Society of Anesthesiologists score, pancreatic texture, Wirsung duct diameter, and blood loss. An overall risk score (0-15) can be calculated for each patient. Score discriminant power was calculated using a receiver operating characteristic curve. RESULTS: Major complications occurred in 31% of patients compared with 17% in Braga's data. Pancreatic texture and blood loss were independently statistically significant for increased morbidity. Areas under the curve were 0.95 and 0.99 for 4-risk categories and for individual scores, respectively. CONCLUSIONS: The Braga score discriminates well between minor and major complications. Our validation suggests that it can be used as a prognostic tool for major complications after pancreaticoduodenectomy. The clinical implications, that is, whether postoperative treatment strategies should be adapted according to the patient's individual risk, remain to be elucidated.

Life-time growth patterns of pumpkinseed Lepomis gibbosus introduced to Europe, relative to North American populations

The pumpkinseed Lepomis gibbosus, an omnivorous, nest guarding North American sunfish, was introduced into European waters about 100 years ago. To assess growth performance following introduction, we reviewed the available data for North American and European populations of pumpkinseed and compared the back-calculated age-specific growth for juveniles (standard length, SL, at age two) and adults (age two to five increment) as well as adult body size (SL at age five), von Bertalanffy growth model parameters and the index of growth (in length) performance (φ′). For continental comparisons of growth trajectory, mean growth curves for North American and Europe were calculated with the von Bertalanffy model using pooled data sets for each continent. Juvenile growth rate did not differ between European and North American pumpkinseed, but mean adult body size and adult growth rate were both significantly greater in North American than European populations. Adult body size decreased with increasing latitude (ANOVA) in North American populations, but this was not observed with adult growth rate. In contrast, adult body size tended to increase with latitude in European populations. Adult body size correlated significantly with φ′. The von Bertalanffy model described the overall growth patterns of North American and European populations reasonably well, but on the individual population level, length asymptotes were unrealistic (estimates that were > 20 % of the mean back-calculated size for the oldest age class) for a third of European populations and 80% of the North American populations. In contrast to North American pumpkinseed populations, somatic growth in European populations appears to be compromised by limited, but adequate, food resources, probably due to strong intraspecific interactions. This appears to be especially acute in adults, having potential ramifications for life span and reproductive allocation

Quality of life after pulmonary embolism, validation of the French version of the PEmb-QoL questionnaire

Background: The PEmb-QoL is a validated 40-item questionnaire to quantify health-related quality of life in patients having experienced pulmonary embolism (PE). It covers six health dimensions: frequency of complaints, activities of daily living limitations, work-related problems, social limitations, intensity of complaints, and emotional complaints. Originally developed in Dutch and English, we sought to prospectively validate the psychometric properties of a French version of the PEmb-QoL. Methods: We performed a forward and backward translation of the English version of the PEmb-QoL into French. French-speaking consecutive adult patients with an acute, objectively confirmed PE admitted to the emergency department of a Swiss university hospital between 08/2009 and 09/2011 were recruited telephonically. We used standard psychometric tests and criteria to evaluate the acceptability, reliability, and validity of the French version of the PEmb-QoL. We also performed an exploratory factor analysis. Results: Overall, 102 patients were enrolled in the study. The French version of the PEmb-QoL showed good reliability (internal consistency, item-total and inter-item correlations), reproducibility (test-retest reliability), and validity (convergent, discriminant) in French-speaking patients with PE. The exploratory factor analysis suggested three underlying dimensions: limitations in daily activity (items 4b-m, 5a-d), symptoms (items 1a-h and 7), and emotional complaints (items 9a-f and j). Conclusion: We successfully validated the French version of the PEmb-QoL questionnaire in patients with PE. Our results show that the PEmb-QoL is a valuable tool for assessing health-related quality of life after PE in French-speaking patients.

Regional Science trends through the analysis of the main facts of the 51st ERSA Conference

The 51st ERSA Conference held in Barcelona in 2011 was one of the largest ever. By examining the characteristics of the conference, this paper identifies the main trends in Regional Science and draws on a broad array of sources of information: the delegates" demographic details, the conference program itself, a satisfaction survey conducted among delegates, a quality survey addressed to those chairing the sessions and, finally, a bibliometric database including each author signing a paper presented at the conference. We finally run a regression analysis from which we show that for ERSA delegates what matters most is quality, and this must be the direction that future conferences should move toward. Ultimately, ERSA conferences are comprehensive, all-embracing occasions, representing an ideal opportunity for regional scientists to present their work to each other and to network.

Duration of anticoagulation after venous thromboembolism in real world clinical practice.

INTRODUCTION: Venous thromboembolism (VTE) carries a considerable risk of recurrence and anticoagulants should be administered for a minimum of three months. Since little is known about real life management of VTE, we aimed to describe current practice in the secondary prevention of VTE. MATERIALS AND METHODS: Using the database of an international, prospective registry on patients treated for VTE, RIETE, information was collected on risk factors for VTE and bleeding, anticoagulant treatment, and clinical outcomes during follow up. Multivariate analysis using logistic regression was performed to identify predictors of treatment duration. RESULTS: Of 6944 patients with a first episode of VTE 41.1% had unprovoked VTE, 31.8% had transient risk factors, 27.1% had cancer. After the exclusion of patients who died during the first year of observation, the rate of patients treated for >12 months was 55.1%, 41.9%, and 43.2%, respectively (p<0.001). Pulmonary embolism at presentation, recurrence while on treatment, chronic heart failure and age >65 years were independently associated with treatment for >12 months. Body weight <75 kg, anemia, cancer, and the presence of transient risk factors were associated with treatment for 12 months or less. Major bleeding occurred more frequently than recurrent VTE in patients with VTE secondary to transient risk factors and cancer; fatal bleeding was more frequent than fatal recurrent PE in all subgroups. CONCLUSIONS: We observed heterogeneous duration of anticoagulant treatment for the secondary prevention of VTE. A substantial proportion of patients, in particular those with VTE secondary to transient risk factors, may be exposed to a possibly unnecessary risk of bleeding.

El papel de la memoria de trabajo en el cálculo mental un cuarto de siglo después de Hitch = The role of working memory in mental arithmetic a quarter of century after Hitch

Desde que Hitch (1978) publicó el primer estudio sobre el rol de la memoria de trabajo en el cálculo han idoaumentando las investigaciones en este campo. Muchos trabajos han estudiado un único subsistema, pero nuestroobjetivo es identificar qué subsistema de la memoria de trabajo (bucle fonológico, agenda viso-espacial o ejecutivocentral) está más implicado en el cálculo mental. Para ello hemos realizado un estudio correlacional en el quehemos administrado dos pruebas aritméticas y nueve pruebas de la “Bateria de Test de Memòria de Treball” dePickering, Baqués y Gathercole (1999) a una muestra de 94 niños españoles de 7-8 años. Nuestros resultadosindican que el bucle fonológico y sobretodo el ejecutivo central inciden de forma estadísticamente significativa enel rendimiento aritmético

EU-15 sovereign governments’ cost of borrowing after seven years of monetary union

Yield spreads over 10-year German government securities of the EU-15 countries converged dramatically in the seven years after the beginning of Monetary Integration. In this paper, we investigate the relative influence of systemic and idiosyncratic risk factors on their behaviour. Our conclusions suggest that in EMU-countries the relative importance of domestic risk factors (both credit and liquidity risk factors) is higher than that of international factors, which appear to play a secondary but significant role in non-EMU countries.

Control and femtosecond time-resolved imaging of torsion in a chiral molecule

We study how the combination of long and short laser pulses can be used to induce torsion in an axially chiral biphenyl derivative (3,5-difluoro-3 ,5 -dibromo-4 -cyanobiphenyl). A long, with respect to the molecular rotational periods, elliptically polarized laser pulse produces 3D alignment of the molecules, and a linearly polarized short pulse initiates torsion about the stereogenic axis. The torsional motion is monitored in real-time by measuring the dihedral angle using femtosecond time-resolved Coulomb explosion imaging. Within the first 4 picoseconds (ps), torsion occurs with a period of 1.25 ps and an amplitude of 3◦ in excellent agreement with theoretical calculations. At larger times, the quantum states of the molecules describing the torsional motion dephase and an almost isotropic distribution of the dihedral angle is measured.We demonstrate an original application of covariance analysis of two-dimensional ion images to reveal strong correlations between specific ejected ionic fragments from Coulomb explosion. This technique strengthens our interpretation of the experimental data

Time-Delayed Spread of Viruses in Growing Plaques

The spread of viruses in growing plaques predicted by classical models is greater than that measured experimentally. There is a widespread belief that this discrepancy is due to biological factors. Here we show that the observed speeds can be satisfactorily predicted by a purely physical model that takes into account the delay time due to virus reproduction inside infected cells. No free or adjustable parameters are used

'L’escriptura del jo', una proposta d’educació intercultural i tractament de la diversitat per a l’ensenyament secundari obligatori = The writing of I, an intercultural educational proposal and treatment of diversity for Compulsory Secondary Education

The writing of I is a project that starts an itinerary through past, present and future experiences of each of our students based on following research activities. Reading, creation and recreation of text and other items that turn essentially around autobiographical writing and culminate with the elaboration of a free autobiography

Time-series forecasting of pollutant concentration levels using particle swarm optimization and artificial neural networks

This study evaluates the application of an intelligent hybrid system for time-series forecasting of atmospheric pollutant concentration levels. The proposed method consists of an artificial neural network combined with a particle swarm optimization algorithm. The method not only searches relevant time lags for the correct characterization of the time series, but also determines the best neural network architecture. An experimental analysis is performed using four real time series and the results are shown in terms of six performance measures. The experimental results demonstrate that the proposed methodology achieves a fair prediction of the presented pollutant time series by using compact networks.

Political philosophy, ethnology, and time: a study of the notion of historical handicap

This article starts by identifying the crucial importance of the notion of historical handicap for the present-day social sciences of Latin America. Such notion is not an original invention made by Latinamericanists. On the contrary, I demonstrate that the genealogy of the notion of historical handicap must be sought in the tradition of Western political philosophy. Such genealogy must take into account the way it was integrated into ethnological descriptions. When and how did the Other become the backward, the primitive? While this relation was secondary for ancient Greek thought, theories of historical development became the main source of ethnological categories in the modern era. Interestingly enough, this modern synthesis suited the practical purpose of justifying two successive waves of European imperialistic: the era of discoveries, and 19th century colonialism. The article concludes by raising questions about the present role and application of the social sciences.

Frequency-Domain and Wide-Pulse Time-Domain Measurements of Lanthanide Luminescence and Lanthanide-Based Resonance Energy Transfer

Resonance energy transfer (RET) is a non-radiative transfer of the excitation energy from the initially excited luminescent donor to an acceptor. The requirements for the resonance energy transfer are: i) the spectral overlap between the donor emission spectrum and the acceptor absorption spectrum, ii) the close proximity of the donor and the acceptor, and iii) the suitable relative orientations of the donor emission and the acceptor absorption transition dipoles. As a result of the RET process the donor luminescence intensity and the donor lifetime are decreased. If the acceptor is luminescent, a sensitized acceptor emission appears. The rate of RET depends strongly on the donor–acceptor distance (r) and is inversely proportional to r6. The distance dependence of RET is utilized in binding assays. The proximity requirement and the selective detection of the RET-modified emission signal allow homogeneous separation free assays. The term lanthanide-based RET is used when luminescent lanthanide compounds are used as donors. The long luminescence lifetimes, the large Stokes’ shifts and the intense, sharply-spiked emission spectra of the lanthanide donors offer advantages over the conventional organic donor molecules. Both the organic lanthanide chelates and the inorganic up-converting phosphor (UCP) particles have been used as donor labels in the RET based binding assays. In the present work lanthanide luminescence and lanthanide-based resonance energy transfer phenomena were studied. Luminescence lifetime measurements had an essential role in the research. Modular frequency-domain and time-domain luminometers were assembled and used successfully in the lifetime measurements. The frequency-domain luminometer operated in the low frequency domain ( 100 kHz) and utilized a novel dual-phase lock-in detection of the luminescence. One of the studied phenomena was the recently discovered non-overlapping fluorescence resonance energy transfer (nFRET). The studied properties were the distance and temperature dependences of nFRET. The distance dependence was found to deviate from the Förster theory and a clear temperature dependence was observed whereas conventional RET was completely independent of the temperature. Based on the experimental results two thermally activated mechanisms were proposed for the nFRET process. The work with the UCP particles involved the measurement of the luminescence properties of the UCP particles synthesized in our laboratory. The goal of the UCP particle research is to develop UCP donor labels for binding assays. In the present work the effect of the dopant concentrations and the core–shell structure on the total up-conversion luminescence intensity, the red–green emission ratio, and the luminescence lifetime was studied. Also the non-radiative nature of the energy transfer from the UCP particle donors to organic acceptors was demonstrated for the first time in aqueous environment and with a controlled donor–acceptor distance.