First, when there is sufficient water, secondary roots are formed at the stem nodes, and the secondary roots can absorb nutrients and water in large quantities, so that the nutrient grows vigorously, and the vines grow long, which inhibits the reproductive growth and the growth of the tubers is slow. At the same time, the secondary roots will also grow small tubers, resulting in insufficient nutrients and the phenomenon of “everyone is not eating enoughâ€, resulting in low yield of sweet potatoes. In this case, the sweet potato vines will often turn, control the formation of secondary roots, inhibit leggy, thus providing more nutrients for reproductive growth, so that the rapid growth of potato. Second, in the case of drought and water shortage, it is necessary to not flip or turn sweet potato vines, so that the secondary roots at the stem nodes will be generated, which will provide more water and nutrients for the growth of the plants, which is conducive to plant growth and survival. Otherwise, it is not conducive to plant growth and survival, sweet potatoes will reduce production. Medical ultrasound (also known as diagnostic sonography or ultrasonography) is a diagnostic imaging technique based on the application of ultrasound. It is used to create an image of internal body structures such as tendons, muscles, joints, blood vessels, and internal organs. Its aim is often to find a source of a disease or to exclude pathology. The practice of examining pregnant women using ultrasound is called obstetric ultrasound, and was an early development and application of clinical ultrasonography. Full-Digital Ultrasound Machine Medical Full-Digital Pregnancy Fetal Diagnostic，Trolley Ultrasound Machine for Sale，Mindray Ultrasound Machine,Full-Digital Laptop Ultrasound Machine Unimedsume Trading Co., Ltd , https://www.ums-labmed.com
Ultrasound are sound waves with frequencies which are higher than those audible to humans (>20,000 Hz). Ultrasonic images, also known as sonograms, are made by sending pulses of ultrasound into tissue using a probe. The ultrasound pulses echo off tissues with different reflection properties and are recorded and displayed as an image.
Many different types of images can be formed. The most common is a B-mode image (Brightness), which displays the acoustic impedance of a two-dimensional cross-section of tissue. Other types can display blood flow, motion of tissue over time, the location of blood, the presence of specific molecules, the stiffness of tissue, or the anatomy of a three-dimensional region.
Compared to other dominant methods of medical imaging, ultrasound has several advantages. It provides images in real-time and is portable and can be brought to the bedside. It is substantially lower in cost than other imaging modalities and does not use harmful ionizing radiation. Drawbacks include various limits on its field of view, such as the need for patient cooperation, dependence on physique, difficulty imaging structures behind bone and air or gases,[note 1] and the necessity of a skilled operator, usually a trained professional.