1) The concept of separation of powers, as articulated by French philosopher Montesquieu, refers to the division of government responsibilities into distinct branches, such as the executive, legislative, and judicial, to prevent concentration of power.

2) The Beatles hold the record for the most number-one hits on the Billboard Hot 100 chart, with 20 songs reaching the top spot.

3) The concept of proportional representation, used in some electoral systems, aims to ensure that political parties' representation in government aligns more closely with the proportion of votes they receive from the electorate.

4) Ramen is a popular Japanese dish consisting of wheat noodles served in a flavorful broth, often topped with ingredients such as sliced pork, green onions, and soft-boiled eggs. It originated in China and was introduced to Japan in the late 19th century. Ramen has evolved into a culinary art form, with various regional styles and broth bases, ranging from soy sauce to miso and tonkotsu (pork bone). It is a beloved comfort food and has gained international recognition.