Multidirectional ECG Coherent Optimal Timing of Defibrillation Shocks

A method for of delivering a defibrillation shock to a heart at an optimal time to stop ventricular fibrillation which involves obtaining an electrocardiogram of a heart in at least two directions, determining a time-coherency of the electrocardiogram based upon each of the at least two directions, and computing a tracking function from the time-coherency. An optimal time to apply a defibrillation shock to the heart is determined by locating a local maximum on the tracking function. The method utilizes spacia characteristics of the ventricular fibrillation. The method can be incorporated into implantable cardioverter defibrillators utilizing existing hardware technology

Supernormal Conduction and Suppression of Spatially Discordant Alternans of Cardiac Action Potentials

Spatially discordant alternans (DA) of action potential durations (APD) is thought to be more pro-arrhythmic than concordant alternans. Super normal conduction (SNC) has been reported to suppress formation of DA. An increase in conduction velocity (CV) as activation rate increases, i.e., a negative CV restitution, is widely considered as hallmark of SNC. Our aim in this study is to show that it is not an increase in CV for faster rates that prevents formation of DA, rather, it is the ratio of the CV for the short relative to the long activation that is critical in DA suppression. To illustrate this subtlety, we simulated this phenomenon using two approaches; (1) by using the standard, i.e., S1S2 protocol to quantify restitution and disabling the slow inactivation gate j of the sodium current (INa), and (2) by using the dynamic, i.e., S1S1 protocol for quantification of restitution and increasing INa at different cycle lengths (CL). Even though both approaches produced similar CV restitution curves, DA was suppressed only during the first approach, where the CV of the short of the long-short action potential (AP) pattern was selectively increased. These results show that negative CV restitution, which is considered characteristic of SNC, per se, is not causal in suppressing DA, rather, the critical factor is a change in the ratio of the velocities of the short and the long APs

Supernormal Conduction and Suppression of Spatially Discordant Alternans of Cardiac Action Potentials

Spatially discordant alternans (DA) of action potential durations (APD) is thought to be more pro-arrhythmic than concordant alternans. Super normal conduction (SNC) has been reported to suppress formation of DA. An increase in conduction velocity (CV) as activation rate increases, i.e., a negative CV restitution, is widely considered as hallmark of SNC. Our aim in this study is to show that it is not an increase in CV for faster rates that prevents formation of DA, rather, it is the ratio of the CV for the short relative to the long activation that is critical in DA suppression. To illustrate this subtlety, we simulated this phenomenon using two approaches; (1) by using the standard, i.e., S1S2 protocol to quantify restitution and disabling the slow inactivation gate j of the sodium current (INa), and (2) by using the dynamic, i.e., S1S1 protocol for quantification of restitution and increasing INa at different cycle lengths (CL). Even though both approaches produced similar CV restitution curves, DA was suppressed only during the first approach, where the CV of the short of the long-short action potential (AP) pattern was selectively increased. These results show that negative CV restitution, which is considered characteristic of SNC, per se, is not causal in suppressing DA, rather, the critical factor is a change in the ratio of the velocities of the short and the long APs

Modelling the Encroachment of Farmhouse Culture on Private Village Pastures and Its Environmental Fall-Out in Northern Western Ghats, India

Tropical India harbours numerous pasturelands across small landholdings ranging up to few hectares which are covered with grass that is suitable as fodder. These grazing lands are commonly known as ‘Gairan’ in urbanised northern Western Ghats mountain tract in Western India). Such grasslands comprise about 20% of the total area of a village (Jodha, 1986), support livestock and supplement the agro-economy of the village. These pasturelands are being replaced by fenced ‘farmhouses’ of the urban elite, resulting in land use changes that caused drastic qualitative and quantitative changes in terms of area, fodder species composition and livestock they support (Patwardhan et al., 2003). The study area has faced large changes in the last few decades with increases in the area under settlement by 240%s as well as a decrease in the area of agriculture land and grasslands-scrub vegetation by 31 % and 39 % respectively (Nalavade, 2003). The present paper documents socio-cultural, economic and environmental changes in private village pastures across the Mumbai-Pune urban belt

What is the impact of physician communication and patient understanding in the management of headache?

Migraine is a common and debilitating condition. Despite the burden of disease and increasing availability of effective treatment, migraine management is unsatisfactory. Evidence in other chronic conditions indicates that effective physician communication results in better patient understanding and health outcomes

Projected changes in climate over the Indus river basin using a high resolution regional climate model (PRECIS)

A regional climate modelling system, the Providing REgional Climates for Impacts Studies developed by the Hadley Centre for Climate Prediction and Research, has been used to study future climate change scenarios over Indus basin for the impact assessment. In this paper we have examined the three Quantifying Uncertainty in Model Predictions simulations selected from 17-member perturbed physics ensemble generated using Hadley Centre Coupled Module. The climate projections based on IPCC SRES A1B scenario are analysed over three time slices, near future (2011-2040), middle of the twenty first century (2041-2070), and distant future (2071-2098). The baseline simulation (1961-1990) was evaluated with observed data for seasonal and spatial patterns and biases. The model was able to resolve features on finer spatial scales and depict seasonal variations reasonably well, although there were quantitative biases. The model simulations suggest a non-uniform change in precipitation overall, with an increase in precipitation over the upper Indus basin and decrease over the lower Indus basin, and little change in the border area between the upper and lower Indus basins. A decrease in winter precipitation is projected, particularly over the southern part of the basin. Projections indicate greater warming in the upper than the lower Indus, and greater warming in winter than in the other seasons. The simulations suggest an overall increase in the number of rainy days over the basin, but a decrease in the number of rainy days accompanied by an increase in rainfall intensity in the border area between the upper and lower basins, where the rainfall amount is highest

Evaluation of gas phase mass transfer at low reynolds numbers: a new model system

A new experimental system is presented which is suitable for studying gas side mass transfer coefficients in packed columns at Reynolds numbers even lower than 1.0. The system involves desorption of iodine from aqueous KI solutions. The reversible complex formation between iodine and iodine ions effectively slows down the concentration changes which otherwise would be too rapid for accurate experimentation

Simulated projections for summer monsoon climate over India by a high-resolution regional climate model (PRECIS)

Impact of global warming on the Indian monsoon climate is examined using Hadley Centre's highresolution regional climate model, PRECIS (Providing REgional Climates for Impact Studies). Three simulations from a 17-member Perturbed Physics Ensemble generated using Hadley Center Coupled Model (HadCM3) for the Quantifying Uncertainty in Model Predictions (QUMP) project, are used to drive PRECIS. The PRECIS simulations corresponding to the IPCCSRES A1B emission scenario are carried out for a continuous period of 1961-2098. The model shows reasonable skill in simulating the monsoon climate over India. The climate projections are examined over three time slices, viz. short (2020s, i.e. 2011-2040), medium (2050s, i.e. 2041-2070) and long (2080s, i.e. 2071-2098). The model projections indicate significant warming over India towards the end of the 21st century. The summer monsoon precipitation over India is expected to be 9-16 more in 2080s compared to the baseline (1970s, i.e. 1961-1990) under global warming conditions. Also, the rainy days are projected to be less frequent and more intense over central India

Soft Palate Modification Using a Collagen Crosslinking Reagent for Equine Dorsal Displacement of the Soft Palate and Other Upper Airway Breathing Disorders

The mechanical properties of the soft palate can be associated with breathing abnormalities. Dorsal displacement of the soft palate (DDSP) is a naturally occurring equine soft palate disorder caused by displacement of the caudal edge of the soft palate. Snoring and a more serious, sometimes life-threatening, condition called obstructive sleep apnea (OSA) are forms of sleep-related breathing disorders in humans which may involve the soft palate. The goal of this study was to investigate the effect of injecting the protein crosslinker genipin into the soft palate to modify its mechanical properties for the treatment of equine DDSP with potential implications for the treatment of snoring and OSA in humans. Ex vivo experiments consisted of mechanical testing and a wind tunnel study to examine the effect of genipin on the mechanical properties, displacement, and vibration of equine soft palates. A pilot in vivo study was completed using DDSP and control horses to test the safety and effectiveness of injecting a genipin reagent into the soft palate. The wind tunnel testing demonstrated a greater than 50% decrease in transient deformation and a greater than 33% decrease in steady-state vibrations for all doses of genipin tested. Ultimate tensile stress, yield stress, and Young’s modulus were higher in the genipin-treated distal soft palate specimens by 52%, 53%, and 63%, respectively. The pilot in vivo study showed a reduction of snoring loudness in all DDSP horses and elimination of DDSP in at least one of three horses. The difficulty of using a 1-meter-long endoscopic injection needle contributed to a consistent overinjection of the equine soft palates, causing excessive stretching (pillowing) and related degradation of the tissue. These ex vivo and in vivo results demonstrated reduced vibration amplitude and flaccidity and increased strength of genipin-treated soft palates, suggesting that genipin crosslinking could become an effective and safe treatment for soft palate related breathing abnormalities