While folk throughout the world had long contributed to efforts to alleviate hunger in the developing world, there has recently been a rapid increase in the numbers involved in tackling domestic hunger even within the economically advanced nations of the Global North. This had happened much earlier in North America than it did in Europe. In the US, the Reagan administration scaled back welfare the early 1980s, leading to a vast increase of charity sector efforts to help Americans unable to buy enough to eat. According to a 1992 survey of 1000 randomly selected US voters, 77% of Americans had contributed to efforts to feed the hungry, either by volunteering for various hunger relief agencies such as food banks and soup kitchens, or by donating cash or food. Europe, with its more generous welfare system, had little awareness of domestic hunger until the food price inflation that began in late 2006, and especially as austerity-imposed welfare cuts began to take effect in 2010. Various surveys reported that upwards of 10% of Europes population had begun to suffer from food insecurity. Especially since 2011, there has been a substantial increase in grass roots efforts to help the hungry by means of food banks, within both the UK and continental Europe. By July 2012, the 2012 US drought had already caused a rapid increase in the price of grain and soy, with a knock on effect on the price of meat.
The increase in stroke volume is explained by the Frank–Starling mechanism, in which increased ventricular pre-load stretches the myocardium such that contractions are more forceful.The regurgitant volume causes a volume overload and a pressure overload of the left atrium and the left ventricle. The increased pressures in the left side of the heart may inhibit drainage of blood from the lungs via the pulmonary veins and lead to pulmonary congestion. Chronic phase
Compensated
If the MR develops slowly over months to years or if the acute phase cannot be managed with medical therapy, the individual will enter the chronic compensated phase of the disease. In this phase, the left ventricle develops eccentric hypertrophy in order to better manage the larger than normal stroke volume. The eccentric hypertrophy and the increased diastolic volume combine to increase the stroke volume (to levels well above normal) so that the forward stroke volume (forward cardiac output) approaches the normal levels.In the left atrium, the volume overload causes enlargement of the left atrium, allowing the filling pressure in the left atrium to decrease. This improves the drainage from the pulmonary veins, and signs and symptoms of pulmonary congestion will decrease.These changes in the left ventricle and left atrium improve the low forward cardiac output state and the pulmonary congestion that occur in the acute phase of the disease. Individuals in the chronic compensated phase may be asymptomatic and have normal exercise tolerances.