Chronic bronchitis is defined as a chronic productive cough lasting at least three months in two consecutive years.

The reticular endothelial system is immune complex from blood and tissues, it mainly comprises of phagocytic cells whose engulf microbes, participate in inflammation,antigen presenting and cytokine secretions. T

Chapter 4: Data and Analog Signals

One of the major functions of the physical layer is to move data in the form of electromagnetic signals across a transmission medium. Generally, the data usable to a person or application is not in a form that can be transmitted over a network. For example, a photograph must first be changed to a form that transmission media can accept. Transmission media work by conducting energy along a physical path. 
 

Lecture Description: This lecture delves into the essential concepts of signals, encoding, and transmission media within the Physical Layer of networking. We begin by exploring signals and their forms—analog and digital—and how they represent data for transmission. Participants will understand the critical characteristics of these signals, such as amplitude, frequency, and phase, which are fundamental to signal manipulation.

Sample collection is the first step in the laboratory investigation process. It involves obtaining biological specimens from patients or subjects. Correct sample collection is crucial for accurate and reliable results.