Transfer Standards To briefly review, a frequency calibration compares the device under test (DUT)to a reference. The DUT is usually a quartz, rubidium, or cesium oscillator. Thereference is an oscillator of higher performance than the DUT or a transfer standardthat receives a radio signal.13).Calibration MethodsTo review, frequency standards are normally calibrated by comparing them to atraceable reference frequency. In this section, weâll discuss how this comparison ismade. To begin with, letâs look at the electrical signal produced by a frequencystandard.
Further information: Factitious diarrhea. The most common cause of melanosis coli is the extended use of laxatives, and commonly anthraquinone containing laxatives such as Senna, Aloe Vera and other plant glycosides. The anthranoid laxatives pass through the gastrointestinal tract unabsorbed until they reach the large intestine, where they are changed into their active forms.
When this happens, the colon. instead relies on the laxatives to bring on bowel movements. In addition, the ongoing use of laxatives may cause a potassium imbalance in the body, which in. rare cases can become a serious health threat. Treatment Options. No medical treatment is necessary for melanosis coli. Patients are advised to stop taking laxatives, which usually reverses the discoloration of the colon after a fairly short period of time. If constipation â generally defined as the passage of small, hard and dry bowel movements fewer.