The problem: Answer a question about this article:
The elimination of wolves from Yellowstone National Park had profound impacts on the trophic pyramid. Without predation, herbivores began to over-graze many woody browse species, affecting the area's plant populations. In addition, wolves often kept animals from grazing in riparian areas, which protected beavers from having their food sources encroached upon. The removal of wolves had a direct effect on beaver populations, as their habitat became territory for grazing. Furthermore, predation keeps hydrological features such as creeks and streams in normal working order. Increased browsing on willows and conifers along Blacktail Creek due to a lack of predation caused channel incision because they helped slow the water down and hold the soil in place.
Broader ecological impacts can occur when an apex predator is removed, in the case of Yellowstone, this includes alteration to the?
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The answer: hydrological features


The problem: Answer a question about this article:
For the remainder of the Korean War the UN Command and the PVA fought, but exchanged little territory; the stalemate held. Large-scale bombing of North Korea continued, and protracted armistice negotiations began 10 July 1951 at Kaesong. On the Chinese side, Zhou Enlai directed peace talks, and Li Kenong and Qiao Guanghua headed the negotiation team. Combat continued while the belligerents negotiated; the UN Command forces' goal was to recapture all of South Korea and to avoid losing territory. The PVA and the KPA attempted similar operations, and later effected military and psychological operations in order to test the UN Command's resolve to continue the war.
What did the UN Command want to achieve with the armistice talks?
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The answer: recapture all of South Korea and to avoid losing territory


The problem: Answer a question about this article:
The most common symptom of LED (and diode laser) failure is the gradual lowering of light output and loss of efficiency. Sudden failures, although rare, can also occur. Early red LEDs were notable for their short service life. With the development of high-power LEDs the devices are subjected to higher junction temperatures and higher current densities than traditional devices. This causes stress on the material and may cause early light-output degradation. To quantitatively classify useful lifetime in a standardized manner it has been suggested to use L70 or L50, which are the runtimes (typically given in thousands of hours) at which a given LED reaches 70% and 50% of initial light output, respectively.
What could cause early light-output degradation in LEDs?
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The answer: higher junction temperatures


The problem: Answer a question about this article:
Meanwhile, the Tumed Mongols began moving into the Kokonor region (modern Qinghai), raiding the Ming Chinese frontier and even as far as the suburbs of Beijing under Altan Khan (1507–1582). Klieger writes that Altan Khan's presence in the west effectively reduced Ming influence and contact with Tibet. After Altan Khan made peace with the Ming dynasty in 1571, he invited the third hierarch of the Gelug—Sönam Gyatso (1543–1588)—to meet him in Amdo (modern Qinghai) in 1578, where he accidentally bestowed him and his two predecessors with the title of Dalai Lama—"Ocean Teacher". The full title was "Dalai Lama Vajradhara", "Vajradhara" meaning "Holder of the Thunderbolt" in Sanskrit. Victoria Huckenpahler notes that Vajradhara is considered by Buddhists to be the primordial Buddha of limitless and all-pervasive beneficial qualities, a being that "represents the ultimate aspect of enlightenment." Goldstein writes that Sönam Gyatso also enhanced Altan Khan's standing by granting him the title "king of religion, majestic purity". Rawski writes that the Dalai Lama officially recognized Altan Khan as the "Protector of the Faith".
What region did the Tumed Mongols move into?
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The answer:
the Kokonor region