Article: Multi-color LEDs offer not merely another means to form white light but a new means to form light of different colors. Most perceivable colors can be formed by mixing different amounts of three primary colors. This allows precise dynamic color control. As more effort is devoted to investigating this method, multi-color LEDs should have profound influence on the fundamental method that we use to produce and control light color. However, before this type of LED can play a role on the market, several technical problems must be solved. These include that this type of LED's emission power decays exponentially with rising temperature, resulting in a substantial change in color stability. Such problems inhibit and may preclude industrial use. Thus, many new package designs aimed at solving this problem have been proposed and their results are now being reproduced by researchers and scientists.

Question: What problem must be solved before multi-color LEDs can play a role in the market?
Ans: power decays exponentially with rising temperature


Article: In his usurpation of the throne from the Jianwen Emperor (r. 1398–1402), the Yongle Emperor was aided by the Buddhist monk Yao Guangxiao, and like his father, the Hongwu Emperor, the Yongle Emperor was "well-disposed towards Buddhism", claims Rossabi. On March 10, 1403, the Yongle Emperor invited Deshin Shekpa, 5th Karmapa Lama (1384–1415), to his court, even though the fourth Karmapa had rejected the invitation of the Hongwu Emperor. A Tibetan translation in the 16th century preserves the letter of the Yongle Emperor, which the Association for Asian Studies notes is polite and complimentary towards the Karmapa. The letter of invitation reads,

Question: Who was Yongle Emperor's father?
Ans: the Hongwu Emperor


Article: Maternal factors also play a role in the body’s immune response. At birth, most of the immunoglobulin present is maternal IgG. Because IgM, IgD, IgE and IgA don’t cross the placenta, they are almost undetectable at birth. Some IgA is provided by breast milk. These passively-acquired antibodies can protect the newborn for up to 18 months, but their response is usually short-lived and of low affinity. These antibodies can also produce a negative response. If a child is exposed to the antibody for a particular antigen before being exposed to the antigen itself then the child will produce a dampened response. Passively acquired maternal antibodies can suppress the antibody response to active immunization. Similarly the response of T-cells to vaccination differs in children compared to adults, and vaccines that induce Th1 responses in adults do not readily elicit these same responses in neonates. Between six to nine months after birth, a child’s immune system begins to respond more strongly to glycoproteins, but there is usually no marked improvement in their response to polysaccharides until they are at least one year old. This can be the reason for distinct time frames found in vaccination schedules.

Question: The difference in responses in infant immune systems is the cause of what?
Ans: distinct time frames found in vaccination schedules


Article: SVCD has two-thirds the resolution of DVD, and over 2.7 times the resolution of VCD. One CD-R disc can hold up to 60 minutes of standard quality SVCD-format video. While no specific limit on SVCD video length is mandated by the specification, one must lower the video bit rate, and therefore quality, to accommodate very long videos. It is usually difficult to fit much more than 100 minutes of video onto one SVCD without incurring significant quality loss, and many hardware players are unable to play video with an instantaneous bit rate lower than 300 to 600 kilobits per second.

Question: How much video can a CD-R contain?
Ans:
60 minutes