Randomized Controlled Studies: This is a study in which 1) There are two groups, one treatment group and one control group. The treatment group receives the treatment under investigation, and the control group receives either no treatment (placebo) or standard treatment. 2) Patients are randomly assigned to all groups.
winds that blow in a steady direction can move a dune. such wind will consistently pick up sand from one side and deposit it to a other side. this causes the entire dune to s â¦ lowly move in the direction if the wind.
This current will move sand along the shore and a beach will be formed. The same current that transports a surfer down the beach from the point of entry will also move beach sand down the shoreline. When this longshore current turns seaward, it is called a rip current. Some areas have underwater canyons near the beach.