Forecast analysis of the incidence of tuberculosis in the province of Quebec

BACKGROUND: While the overall population prevalence of tuberculosis in Quebec has been declining for many years, tuberculosis is still disproportionately more prevalent among the immigrant and Inuit communities. As such, the aim of this study was to forecast the incidence of tuberculosis in the Province of Quebec over time in order to examine the possible impact of future preventative and treatment programs geared to reducing such disparities. METHODS: A compartmental differential equation based on a Susceptible Exposed Latent Infectious Recovered (SELIR) model was simulated using the Euler method using Visual Basic for Applications in Excel. Demographic parameters were obtained from census data for the Province of Quebec and the model was fitted to past epidemiological data to extrapolate future values over the period 2015 to 2030. RESULTS: The trend of declining tuberculosis rates will continue in the general population, falling by 42% by 2030. The incidence among immigrants will decrease but never vanish, and may increase in the future. Among the Inuit, the incidence is expected to increase, reaching a maximum and then stabilizing, although if re-infection is taken into account it may continue to increase. Tuberculosis among non-indigenous Canadian born persons will continue to decline, with the disease almost eradicated in that group in the mid 21st century. CONCLUSIONS: While the incidence of tuberculosis in the Province of Quebec is expected to decrease overall, certain populations will remain at risk

Improving the drug development process by reducing the impact of adverse events:the case of cataracts considered

Cataract was used as a model for the prevalence and economic impact of adverse events during the drug development process. Meta-analysis revealed a reported prevalence of cataract at 12.0% (1.0–43.3%), 3.8% (2.4–12.5%), 1.0% (0.0–8.1%), 1.7% (0.0–34.8%) and 3.8% (2.3–5.7%) of compounds in preclinical, Phase I, II, III and IV clinical trials, respectively. Utilising a human-based in vitro screening assay to predict cataractogenic potential in human could allow better selection of novel compounds at early-stage drug development. This could significantly reduce costs and ultimately increase the probability of a drug obtaining FDA approval for a clinical application

Waves of DNA: Propagating excitations in extended nanoconfined polymers

We use a nanofluidic system to investigate the emergence of thermally driven collective phenomena along a single polymer chain. In our approach, a single DNA molecule is confined in a nanofluidic slit etched with arrays of embedded nanocavities; the cavity lattice is designed so that a single chain occupies multiple cavities. Fluorescent video-microscopy data shows fluctuations in intensity between cavities, including waves of excess fluorescence that propagate across the cavity-straddling molecule, corresponding to propagating fluctuations of contour overdensity in the cavities. The transfer of DNA between neighboring pits is quantified by examining the correlation in intensity fluctuations between neighboring cavities. Correlations grow from an anticorrelated minimum to a correlated maximum before decaying, corresponding to a transfer of contour between neighboring cavities at a fixed transfer time scale. The observed dynamics can be modeled using Langevin dynamics simulations and a minimal lattice model of coupled diffusion. This study shows how confinement-based sculpting of the polymer equilibrium configuration, by renormalizing the physical system into a series of discrete cavity states, can lead to new types of dynamic collective phenomena.Natural Sciences and Engineering Research Council of Canada (Grant NSERC-DG, 386212-10)Canada Foundation for InnovationNatural Sciences and Engineering Research Council of Canada (Postdoctoral Fellowship

Knots modify the coil–stretch transition in linear DNA polymers

We perform single-molecule DNA experiments to investigate the relaxation dynamics of knotted polymers and examine the steady-state behavior of knotted polymers in elongational fields. The occurrence of a knot reduces the relaxation time of a molecule and leads to a shift in the molecule's coil-stretch transition to larger strain rates. We measure chain extension and extension fluctuations as a function of strain rate for unknotted and knotted molecules. The curves for knotted molecules can be collapsed onto the unknotted curves by defining an effective Weissenberg number based on the measured knotted relaxation time in the low extension regime, or a relaxation time based on Rouse/Zimm scaling theories in the high extension regime. Because a knot reduces a molecule's relaxation time, we observe that knot untying near the coil-stretch transition can result in dramatic changes in the molecule's conformation. For example, a knotted molecule at a given strain rate can experience a stretch-coil transition, followed by a coil-stretch transition, after the knot partially or fully unties.National Science Foundation (U.S.) (Grant CBET-1602406

Präsidentialismus in Afrika

Die letzte der fünfzehn Präsidentschaftwahlen des Jahres 2011 des subsaharischen Afrika fand am 28. November in der Demokratischen Republik Kongo statt; Amtsinhaber Joseph Kabila gewann mit zweifelhaften Mitteln. Nachdem im März in Niger und im September in Sambia jeweils neue Staatschefs einen Wahlsieg erringen konnten, hofft man hier auf Beispiele für besseres Regieren aus zwei der mächtigen Präsidentenpaläste Afrikas. Afrika gilt als Kontinent der notorisch übermächtigen Staatspräsidenten. Die präsidentiellen Regierungssysteme südlich der Sahara werden oft als Hemmschuh für Demokratisierung und Entwicklung gesehen. Allerdings ist der formale Präsidentialismus nicht das zentrale Problem. Es mangelt insbesondere an wirksamen politischen Gegengewichten, an handlungsfähigen Parlamenten und einer starken Justiz. Es gibt keinen eindeutigen Zusammenhang zwischen der formalen Macht des Präsidenten und der Herrschaftsform. Oft ist der Präsidentialismus nicht Ursache fehlender Demokratie, sondern Folge von autoritärer Herrschaft. "Ewige" Präsidenten stützen ihre autoritäre Herrschaft zumeist auf andere Machtmittel als das Regierungssystem. Formal haben sie in vielen Fällen weniger Kompetenzen als einige demokratisch gewählte Kollegen. Große Reformen zu einem parlamentarischen Regierungssystem, in dem es keinen direkt gewählten Präsidenten gibt, sind schwer durchsetzbar und kein Garant für mehr Demokratie. Vielversprechender ist eine Stärkung des Parlaments und der Verfassungsjustiz innerhalb des Präsidentialismus. Oft ist dazu gar keine Verfassungsreform nötig, da viele afrikanische Parlamente ihre vorhandenen Machtbefugnisse nicht effektiv nutzen. Eine institutionelle Ordnung kann Demokratie nur dann unterstützen, wenn der politische Kontext stimmt. Endemische Korruption, geringe Akzeptanz formaler Verfahren oder autoritäre Einschüchterung unterlaufen auch parlamentarische Regierungssysteme

Modellierung und Messung von Emissionen an Transceiverpins in Automotive-System-ICs, verursacht durch integrierte DC/DC-Wandler

Die Integration von DC/DC-Wandlern mit Transceivern in Automotive-System-ICs führt zu neuen Herausforderungen im Bezug auf die Einhaltung der Emissionsgrenzwerte an den Transceiverpins. An einem Test-IC werden die Emissionen des DC/DC-Wandlers an verschiedenen Transceiverpins ermittelt. Der Substratübertragungspfad wird mit Hilfe eines neuartigen Substratextraktors modelliert, und zur Beschreibung induktiver Bonddrahtkopplungen wird ein HFSS-Packagemodell verwendet. Der Vergleich zwischen Modellvorhersage und Messung zeigt typ. eine Abweichung von unter _6 dB bis 1 GHz

Reduction of CPR artifacts in the ventricular fibrillation ECG by coherent line removal

<p>Abstract</p> <p>Background</p> <p>Interruption of cardiopulmonary resuscitation (CPR) impairs the perfusion of the fibrillating heart, worsening the chance for successful defibrillation. Therefore ECG-analysis <it>during ongoing chest compression </it>could provide a considerable progress in comparison with standard analysis techniques working only during "hands-off" intervals.</p> <p>Methods</p> <p>For the reduction of CPR-related artifacts in ventricular fibrillation ECG we use a localized version of the <it>coherent line removal </it>algorithm developed by Sintes and Schutz. This method can be used for removal of periodic signals with sufficiently coupled harmonics, and can be adapted to specific situations by optimal choice of its parameters (e.g., the number of harmonics considered for analysis and reconstruction). Our testing was done with 14 different human ventricular fibrillation (VF) ECGs, whose fibrillation band lies in a frequency range of [1 Hz, 5 Hz]. The VF-ECGs were mixed with 12 different ECG-CPR-artifacts recorded in an animal experiment during asystole. The length of each of the ECG-data was chosen to be 20 sec, and testing was done for all 168 = 14 × 12 pairs of data. VF-to-CPR ratio was chosen as -20 dB, -15 dB, -10 dB, -5 dB, 0 dB, 5 dB and 10 dB. Here -20 dB corresponds to the highest level of CPR-artifacts.</p> <p>Results</p> <p>For non-optimized <it>coherent line removal </it>based on signals with a VF-to-CPR ratio of -20 dB, -15 dB, -10 dB, -5 dB and 0 dB, the signal-to-noise gains (SNR-gains) were 9.3 ± 2.4 dB, 9.4 ± 2.4 dB, 9.5 ± 2.5 dB, 9.3 ± 2.5 dB and 8.0 ± 2.7 (mean ± std, <it>n </it>= 168), respectively. Characteristically, an original VF-to-CPR ratio of -10 dB, corresponds to a variance ratio <it>var</it>(VF):<it>var</it>(CPR) = 1:10. An improvement by 9.5 dB results in a restored VF-to-CPR ratio of -0.5 dB, corresponding to a variance ratio <it>var</it>(VF):<it>var</it>(CPR) = 1:1.1, the variance of the CPR in the signal being reduced by a factor of 8.9.</p> <p>Discussion</p> <p>The <it>localized coherent line removal </it>algorithm uses the information of a single ECG channel. In contrast to multi-channel algorithms, no additional information such as thorax impedance, blood pressure, or pressure exerted on the sternum during CPR is required. Predictors of defibrillation success such as mean and median frequency of VF-ECGs containing CPR-artifacts are prone to being governed by the harmonics of the artifacts. Reduction of CPR-artifacts is therefore necessary for determining reliable values for estimators of defibrillation success.</p> <p>Conclusions</p> <p>The <it>localized coherent line removal </it>algorithm reduces CPR-artifacts in VF-ECG, but does not eliminate them. Our SNR-improvements are in the same range as offered by multichannel methods of Rheinberger et al., Husoy et al. and Aase et al. The latter two authors dealt with different ventricular rhythms (VF and VT), whereas here we dealt with VF, only. Additional developments are necessary before the algorithm can be tested in real CPR situations.</p