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Typically, a stimulus causes ionic changes in the receptor neuron's dendrites, which lead to the formation of action potentials in the receptor neurons. Some neurotransmitters cause the postsynaptic cell to hyperpolarize (the membrane potential becomes more negative, which would inhibit the formation of action potentials in the postsynaptic cell). An action potential passes down the presynaptic cell into its end terminals. Colder temperatures slow down the action potential, but this usually doesn't happen in an individual. While flooding is a serious problem, the most immediate threat from hurricanes is their powerful winds, which in a worst-case scenario can attain speeds of more than 150 miles (241 kilometers) per hour -- enough to snap trees like twigs, knock down utility poles, rip off roofs and demolish house walls. Prepaid mobile Internet uses 3G mobile devices like a BlackBerry, iPhone and other smartphones as modems to connect a computer to the Internet. Many Internet service providers (ISPs) have implemented bandwidth caps, what is control cable which are limits on the amount of data you're allowed to transfer over their network each month. These airborne networks will overcome the last-mile barriers facing conventional Internet access options.

Philadelphia, Pennsylvania: Philadelphia wanted to bridge the digital divide, so its network provides low-cost access for everyone and discounted access for low-income families. It would take a lot of time to provide universal access using cable or phone lines, just because of the time it takes to install the wires. The recording shows the time it takes for the nerve to conduct the electrical impulse across the distance. The distance your data has to travel will also affect how long it takes to get there, and there could be additional bottlenecks at any hardware and cabling the data has to travel through to get to its destination. The distance needed to achieve a New York to San Francisco connection was impossible to overcome with available technology. In this test, two small electrodes are placed a fixed distance apart from each other on the surface of the skin above a nerve. By dividing the distance by time, the physician (or the machine) calculates the conduction velocity. The test is often performed when a conduction block or demyelinating disease (like multiple sclerosis) is suspected. However, you can use cold-block techniques to temporarily anesthetize an area (like putting ice on an injured finger).

However, Microsoft still got a jump on its competitors, as the PlayStation 3 and the Nintendo Wii did not release until 2006. According to industry analyst the NPD Group, as of August 2007, the Xbox 360 sold 6.3 million Xbox 360s in the United States, to 4 million of Nintendo's Wii and 1.75 million Sony Playstation 3s. Microsoft has outfitted the 360 with a 165-million transistor, multi-core processor running three 3.2-GHz PowerPC cores. Cores are made of metal alloys: nickel - chromium - aluminum, copper - nickel, brass, etc. Conductor is enclosed in a protective shell, which is covered with additional insulation. In the case of satellite TV systems or digital cable, no encoders are used within the box because the satellite or cable company has converted the signal to digital already. This enables the nerve signal to be turned "off" and readies the synapse to receive another action potential. The action potential will travel the length of the postsynaptic cell to another synapse on the effector cell (like a muscle cell, skin, blood vessel, gland), where its neurotransmitter will cause a response in the effector cell (like a muscle contraction).

Nerve cells send chemical messages with neurotransmitters in a one-way direction across the synapse from presynaptic cell to postsynaptic cell. Similarly, many local anesthetics (e.g. lidocaine, novocaine, benzocaine) can prevent action potentials from being propagated in the nerve cells in an area and temporarily prevent you from feeling pain. Such toxic substances include venoms, heavy metals (like mercury and lead) and anesthetics. Toxic substances interfere with sodium or potassium channels, whose actions underlie the action potential. The action potential is an "all-or-none" response. As the intensity of the stimulus increases, so does the frequency of action potentials. Information is encoded by the frequency of action potentials, much like FM radio. So, if the size of the action potential does not vary, how does an action potential code information? The propagation of the action potential is also sensitive to temperature in experimental settings. Changes in temperature could affect the movements of ions across the cell membrane and influence action potentials in that way.