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تدخل الموجات الصوتية إلى الأذن بعد أن يقوم الصيوان بتجميعها، ثم تمر عبر القناة السمعية الخارجية (الصورة:gg) إلى الطبلة (الصورة:tf) التي تحولها إلى اهتزازات تنتقل إلى المطرقة (الصورة:h) فالسندان (الصورة:a) فالركاب (الصورة:s) وثم إلى القوقعة التي يؤدي اهتزاز القناتين السمعية (الصورة:tht) والدهليزية (الصورة:vht) فيها إلى توليد سلسلة من الذبذبات تنتقل بواسطة العصب السمعي إلى المخ بصورة سيالات عصبية، حيث تترجم هناك إلى أصوات نسمعها.
The central nervous system (CNS) actions that result from taking even small amounts of methamphetamine include increased wakefulness, increased physical activity, decreased appetite, increased respiration, hyperthermia, and euphoria. Other CNS effects include irritability, insomnia, confusion, tremors, convulsions, anxiety, paranoia, and aggressiveness. Hyperthermia and convulsions can result in death.

And it certainly is not supposed to do that at such high temperatures. Marzari, who predicted the phenomenon at almost the same time as Chen, was therefore fairly confident that it would prove valid. Even so, he was less certain that second sound would be seen at the foreseen high temperatures. “If you had asked me to bet my mortgage on the existence of this effect, I would have said yes,” Marzari says. “But the question is always does it happen at 100 Kelvin, 20 Kelvin or 0.1 Kelvin?” Duncan’s experiment found the effect at 120 Kelvin—more than 10 times higher than previous measurements. “Nobody ever thought that you would actually be able to do this at such high temperatures,” says Venkatesh Narayanamurti, a research professor of technology and public policy at Harvard University who was not involved in the study. “In that sense, it breaks some conventional wisdom.”
كانت صدمة كبيرة لي ولأهلي. شعرت أني أخذت صفعة على وجهي لكي أستيقظ من هذه الحياة وهذا الوهم. لم أصدق نفسي إنه يتم التحقيق معي، وأني معرض للسجن لمدة ليست قصيرة، وضياع مستقبلي. والدي فعل المستحيل لكي ينقذني من هذة القضية ونجح في ذلك. بعد هذه التجربة أخذت قراراً مع نفسي إني لن أعود لهذه الحياة مرة أخرى، ولن أقوم بهذه الأشياء مرة أخرى، وسوف أترك هذه الصحبة، وسوف ألتفت إلى مستقبلي ودراستي.
Laughing gas is available several forms, one being the medical form which is produced to be used as an anaesthetic and is therefore subject to pharmaceuticals law. A second, less pure form of laughing gas is for commercial use and is commonly used to tune engines. This less pure form may often contain other chemicals or gases such as methyl nitrate which can lead to oxygen deficiency in the human body. Laughing gas can also be purchased in cartridges that can be used to make whipped cream.
In addition to nicotine, cigarette smoke is primarily composed of a dozen gases (mainly carbon monoxide) and tar. The tar in a cigarette, which varies from about 15 mg for a regular cigarette to 7 mg in a low-tar cigarette, exposes the user to a high expectancy rate of lung cancer, emphysema, and bronchial disorders. The carbon monoxide in the smoke increases the chance of cardiovascular diseases. The Environmental Protection Agency has concluded that second hand smoke causes lung cancer in adults and greatly increases the risk of respiratory illnesses in children and sudden infant death.
It is no wonder that Duncan, a graduate student at the Massachusetts Institute of Technology, could not quite believe his eyes. To ensure that he had not made a mistake, he quadruple-checked everything within his set-up, ran the experiment again, and took a mental-health break. “I tried to get some sleep, knowing that I wouldn’t be able to tell if the experiment was successful or not for several more hours, but I was finding it pretty difficult to shut down for the night,” he recalls. When Duncan’s alarm went off the next morning, he ran to his computer (still in his pajamas) and crunched the new measurements only to confront the same result: Heat had still moved impossibly fast.
وتعتبر الجريمة أحد الآثار الأكثر خطورة لتعاطي المخدرات على المجتمع، وعلى الرغم من أن العديد من حالات الإدمان، (مثل تعاطي الحبوب المنومة التي تصرف بوصفة طبية)، نادراً ما تدفع من يحترمون القانون للإتيان بالسلوكيات الإجرامية، إلا أن الأنواع الأخرى من المخدرات مثل الهيروين، والأفيونات، يمكن أن تؤدي بشكل مباشر إلى زيادة معدلات الجريمة في مجتمعات معينة سواء على المستوى الوطني أو الدولي.
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