Non-Standard Errors

In statistics, samples are drawn from a population in a data-generating process (DGP). Standard errors measure the uncertainty in estimates of population parameters. In science, evidence is generated to test hypotheses in an evidence-generating process (EGP). We claim that EGP variation across researchers adds uncertainty: Non-standard errors (NSEs). We study NSEs by letting 164 teams test the same hypotheses on the same data. NSEs turn out to be sizable, but smaller for better reproducible or higher rated research. Adding peer-review stages reduces NSEs. We further find that this type of uncertainty is underestimated by participants

Análisis de los procesos de mantenimiento predictivo y su influencia en la operatividad continua de parqueo en la Unidad Académica Ciencias de la Ingeniería

Modelo de mantenimiento preventivo (PM) se han concentrado tradicionalmente en la utilización de maquinas de la información "técnicas" del estado tales como el grado de deterioro

Anomalously slow attrition times for asymmetric populations with internal group dynamics

The many-body dynamics exhibited by living objects include group formation within a population and the nonequilibrium process of attrition between two opposing populations due to competition or conflict. We show analytically and numerically that the combination of these two dynamical processes generates an attrition duration T whose nonlinear dependence on population asymmetry x is in stark contrast to standard mass-action theories. A minority population experiences a longer survival time than two equally balanced populations, irrespective of whether or not the majority population adopts such an internal grouping. Adding a third population with predefined group sizes allows T(x) to be tailored. Our findings compare favorably to real-world observations

Abstract 17011: Correlation of Surface Atrial ECG Dominant Frequency to Intracardiac Atrial Electrogram Dominant Frequency

Abstract only Background: The surface Atrial ECG (A-ECG) is an underused tool in persistent atrial fibrillation (PeAF) that can provide dominant frequency (DF) of atrial activation. The association between A-ECG DF and left (LA) and right atrial (RA) DF has not been established. Research Question: Does surface A-ECG DF correlate with intracardiac DF? Aims: To investigate the correlation between A-ECG peak DF and peak DF of intracardiac RA and LA electrograms (EGM) in patients with PeAF. Methods: Thirty-two patients (age 63±9 years; 71% males) with PeAF underwent 5-minute epochs of surface ECG and comprehensive LA (261.5±185.1 sites/patient) and RA (211.5±174.6 sites/patient) intracardiac mapping with 15 second recordings. The A-ECG was derived by QRST subtraction and independent component analysis filtering, and divided into overlapping10-second windows which were subjected to Fast Fourier Transform (FFT). 4 were excluded for significant artifact. A-ECG DF was calculated for each lead from the power spectrum as the average of all 10-second segments. Peak A-ECG DF was determined by regional lead location and for all 12 leads. The intracardiac EGM DF was calculated from the FFT, and peak RA and LA DF was determined. Results: A-ECG peak DF was significantly lower than intracardiac peak DF 6.08±0.64 vs 9.72±1.19 Hz, p<0.0001(LA: 9.72±1.20 Hz, p<0.0001; RA: 8.40±0.80 Hz, p<0.0001). Figure shows that A-ECG peak DF correlated with peak RA DF, r=0.77 (p<0.0001), but not with peak LA DF (r=0.31, p=0.10). Regional A-ECG lead group DF correlated with RA DF (Inferior (II, III, aVF): r=0.79, p<0.0001; Lateral (I, aVL, V5-6): r=0.78, p<0.0001; Anterior (V1-3): r=0.75, p<0.0001) but not with peak LA DF. Conclusion: Surface A-ECG DF correlates with intracardiac RA DF and not LA DF. As in atrial flutter, the RA plays a prominent role in the surface ECG manifestation of the f waves. Further study is needed to determine whether A-ECG DF can be used to identify RA versus LA drivers that may require ablation

Abstract 16967: Effect of Catheter Ablation of Persistent Atrial Fibrillation on Surface Atrial ECG Dominant Frequency

Abstract only Background: There are no standard techniques to track effects of catheter ablation (CA) of persistent atrial fibrillation (PeAF). The Atrial ECG (A-ECG) derived from the standard ECG provides the atrial dominant frequency (DF), an estimation of atrial rate. Research Question: Does CA for PeAF diminish A-ECG DF? Aims: To evaluate change in A-ECG peak DF pre- and post-CA. Methods: We obtained 1-minute epochs of surface ECG pre- and post-CA in 32 patients (age 63±9 years; 71% males) undergoing CA for PeAF. A-ECG was derived by QRST subtraction and independent component analysis filtering, and divided into overlapping10-second windows, each subjected to Fast Fourier Transform. DF was calculated for each lead as the average DF for all 10-sec segments. Peak A-ECG DF was assessed by regional lead group and among all leads. 10 patients were excluded for significant artifact. Of the 22 analyzed patients, all had pulmonary vein isolation and 3 had posterior wall isolation. Two-year outcomes were available in 20 patients (13 were free from recurrent AF). Results: The figure shows the change in the time-frequency plot (left panel) of DF for one subject and the shift in the spectra (right panel) with CA. A-ECG peak DF was significantly lower post- versus pre-CA: 5.96±0.63 vs 6.16±0.64 Hz, p=0.0009. By lead group, peak DFs were all lower post CA - Anterior (V1-3): 5.94±0.62 vs 6.13±0.64 Hz, p=0.0015; Inferior (II, III, aVF): 5.82±0.63 vs 6.01±0.66 Hz, p=0.0040; Lateral (I, aVL, V5-6): 5.82±0.64 vs 5.99±0.63 Hz, p=0.0015. In this small cohort, there was no significant difference in change of peak DF in those free from AF versus with recurrent AF (-2.4±4.3% vs -4.6±3.7%, p=0.26). Conclusion: The A-ECG provides physiologic information of activation rate in PeAF, but despite current, advanced signal processing techniques is analyzable in only 69% of patients. CA results in a significant reduction in DF. Clinical implications of these CA induced changes require further study

Descoloração simultânea e a desintoxicação do preto reativo 5 com TiO2 depositadas em vidro de borosilicato pela técnica de sedimentação.

Objective. Removal and detoxification of azo dye by photocatalysis with TiO2. Materials and methods. TiO2 films were prepared by sedimentation at pH 1.3, using as support a borosilicate glass, annealed for 1 hour at 450 °C. Physical characterization was performed by Scanning Electron Microscopy, X-ray diffraction and UV/VIS spectrometry. Dye Black Reactive 5 removal was carried-out in a quartz photo-reactor. Results. Optical characterization revealed the films displayed evident TiO2 spherical particles of various irregular sizes, porous, and without fractures. The average crystal size was 77.5 nm and 77.7 nm for 50 °C (dried temperature) and 450 ºC (annealed temperature) respectively. The energy of the band gap (GAP) was 3.02 and 2.68 eV respectively. Maximum concentration of dye that negatively affected color removal was 80 mg/L (17%). At lower dye’s concentrations (10, 50 and 70mg/L) decolorization was greater than 80%. TiO2 films were reused for five consecutive cycles of 6 hours at 10 mg/L (&gt;80%), and three cycles of 10 hours at 70 mg/L (&gt; 80%). Toxicity results demonstrate that Daphnia magna was more sensitive than Lactuca sativa. Conclusions. TiO2 films obtained by sedimentation demonstrated a high reactive black 5 decolorization and COD removal (86% and 100%), as well as toxicity reduction.Key words: photocatalysis with TiO2, sedimentation techniques, reactive black 5, Lactuca sativa and Daphnia magna.Objetivo. Decolorización y disminución de la toxicidad de un azo colorante usando fotocatálisis con TiO2. Materiales y métodos. Las películas de TiO2 fueron crecidas por sedimentación a pH 1,3 empleando vidrio de borosilicato como sustrato. La caracterización física se realizó por medio de microscopía electrónica de barrido, difracción de rayos X y espectrometría de absorción UV/vis. Los estudios de remoción del colorante Negro Reactivo 5, se realizaron en un fotoreactor de cuarzo. Resultados. De acuerdo con la caracterización óptica, las películas de TiO2 presentaron partículas esféricas, con diferentes tamaños, irregulares y sin fracturas. El tamaño del cristal fue 77,5 nm y 77,7 nm para 50 y 450º C y la energía de banda prohibida fue 3,02 y 2,68 eV, respectivamente. La concentración máxima del colorante que afectó negativamente la remoción de color fue 80 mg/L (17%). A concentraciones más bajas de NR5 (10, 50 y 70 mg/L) la decoloraciónfue superior al 80%. Las películas de TiO2 se reutilizaron por 5 ciclos de 6 horas a 10 mg/L y 3 ciclos de 10 h a 70 mg/L. Los estudios de toxicidad en Lactuca sativa y Daphnia magna demostraron que D. magna fue más sensible que L. sativa. Conclusión. Las películas de TiO2 crecidas por sedimentación decoloraron el colorante negro reactivo 5 en un 86% y removieron la demanda química de oxígeno en un y 100%, igualmente redujeron la toxicidad.Palabras clave: fotocatálisis con TiO2, técnica de sedimentación, negro reactivo 5, Lactuca sativa and Daphnia magna.Objetivo. Descolorar e diminuir a toxicidade de um corante azo utilizando fotocatálise com TiO2. Materiais e métodos. Os filmes de TiO2 foram obtidos por sedimentação a pH 1,3 usando vidro de borosilicato como substrato. A caracterização física foi realizada por microscopia eletrônica de varredura, difração de raios X e espectrometria de absorção UV/vis. Os estudos de remoção de corante Preto Reativo 5, foram realizados num fotorreator de quartzo. Resultados. De acordo com a caracterização óptica, os filmes de TiO2 presentearão partículas esféricas com tamanhos diferentes, irregulares e sem fracturas. O tamanho do cristal foi de 77,5 nm e 77,7 nm para 50 e 450°C e a energia de banda proibida foi 3,02 e 2,68 eV, respectivamente. A concentração máxima do corante que afetou negativamente a remoção de cor foi de 80 mg/L (17%), em concentrações mais baixas (70, 50 e 10 mg/L) a descoloração foi superior a 80%. Os filmes TiO2 foram reutilizados em 5 ciclos de 6 horas a 10 mg/L e 3 ciclos de 10 horas a 70 mg/L. Os estudos de toxicidade com Lactuca sativa e Hydra attenuata demonstraram que H. attenuata foi mais sensível que L. sativa. Conclusão. Os filmes de TiO2 obtidos por sedimentação descoloram o corante Preto Reativo 5 e removeram a demanda química de oxigênio em 86% e 100%, respectivamente; do mesmo modo reduziram a toxicidade.Palavras-chave: fotocatálise com TiO2 técnica de sedimentação, Preto Reativo 5, Lactuca sativa e Daphnia magna

Abstract 16896: Electrogram Morphology Recurrence to Characterize Drivers of Persistent Atrial Fibrillation: Findings at Initial versus Redo Catheter Ablation

Background: Electrogram (EGM) morphology recurrence (EMR) mapping of persistent atrial fibrillation (PeAF) quantifies consistency of activation at each site and is expected to be high and rapid near drivers of PeAF. Objective: To compare EMR in the left (LA) and right atrium (RA) in patients undergoing first- vs second-time PeAF catheter ablation (CA). Methods: Multisite bipolar EGM mapping of the LA (265±153 sites) and RA (224±148 sites) prior to CA for PeAF was performed in 40 patients (29 males, age 63±9 yrs, CHA2DS2-VASc 2.4±1.5, LVEF 48±12%) undergoing first (Group 1, n=31) or second-time (Group 2, n=9) CA. After cross-correlation of each automatically detected EGM with every other EGM in the recording, the most recurrent EGM morphology was identified and its frequency (Rec%) and cycle length of recurrence (CL R ) were computed (figure). The minimum CL R sites were identified. Results: In group 1, shortest CL R was in the LA in 26 patients (84%) and RA in 5 patients (16%). In the LA, there were 1 (n=23), 2 (n=2), or 3 (n=1) areas of shortest CL R , most commonly in the pulmonary veins (PV; n=19). In the RA, there was only 1 area of shortest CL R . Minimum CL R was 174.1±25.4 ms (LA-179.6±37.4 vs RA-207.9±34.5, p=0.0004), with Rec% 95±10%. In group 2, shortest CL R was in the LA in 5 patients and RA in 5 patients (56%)– one had both LA and RA. In the LA/RA, there were 1 (n=3/4) or 2 (n=2/1) areas of shortest CL R . The most common LA site was non-PV (6/7, 85.7%). The minimum CL R was 182.1±26.2ms (LA-190.8±36.2 vs RA-196.0±30.5, p=0.6), with Rec% 96±5%. Conclusion: In 61% of patients undergoing initial CA for PeAF, EMR identified LA drivers in the PVs which may explain why PV isolation has been reported to have 50-60% success rates in PeAF. In patients undergoing a 2 nd ablation for PeAF, EMR identified predominantly nonPV drivers with even distribution of shortest CL R between RA and LA and diminished CL R gradient between the LA and RA. EMR may be a useful mapping tool to characterize potential drivers of PeAF