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Congestion Coefficient For Random Graphs And Scale-free Networks
Congestion may refer to: Medicine *Excessive fluid in tissues, vessels, or both, including: ** Edema, abnormal accumulation of fluid in the interstitium, manifesting as swelling *** Peripheral edema, edema in peripheral body parts such as limbs and feet *** Pulmonary edema, edema in the lungs that impairs breathing ** Congestive heart failure, heart failure resulting in congestion in one or more organs ** Nasal congestion, the blockage of nasal passages due to swollen membranes ** Prostatic congestion, a medical condition that happens when the prostate becomes swollen by excess fluid Other uses * Network congestion, reduced quality of service when a network is carrying more data than it can handle * Traffic congestion, vehicles clogging streets and highways * Congestion pricing Congestion pricing or congestion charges is a system of surcharging users of public goods that are subject to congestion through excess demand, such as through higher peak charges for use of bus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Edema
Edema (American English), also spelled oedema (British English), and also known as fluid retention, swelling, dropsy and hydropsy, is the build-up of fluid in the body's tissue (biology), tissue. Most commonly, the legs or arms are affected. Symptoms may include skin that feels tight, the area feeling heavy, and joint stiffness. Other symptoms depend on the underlying cause. Causes may include Chronic venous insufficiency, venous insufficiency, heart failure, kidney problems, hypoalbuminemia, low protein levels, liver problems, deep vein thrombosis, infections, kwashiorkor, angioedema, certain medications, and lymphedema. It may also occur in immobile patients (stroke, spinal cord injury, aging), or with temporary immobility such as prolonged sitting or standing, and during menstruation or pregnancy. The condition is more concerning if it starts suddenly, or pain or shortness of breath is present. Treatment depends on the underlying cause. If the underlying mechanism involve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interstitium
In anatomy, the interstitium is a contiguous fluid-filled space existing between a structural barrier, such as a cell membrane or the skin, and internal structures, such as organs, including muscles and the circulatory system. The fluid in this space is called interstitial fluid, comprises water and solutes which drains into the lymph system. The interstitial compartment is composed of connective and supporting tissues within the body called the ( extracellular matrix) that are situated outside the blood and lymphatic vessels and the parenchyma of organs. The role of the interstitium in solute concentration, protein transport and hydrostatic pressure impacts human pathology and physiological responses such as edema, inflammation and shock. Structure The non-fluid parts of the interstitium are predominantly collagen types I, III, and V; elastin; and glycosaminoglycans, such as hyaluronan and proteoglycans, that are cross-linked to form a honeycomb-like reticulum. Collagen bundles ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peripheral Edema
Peripheral edema is edema (accumulation of fluid causing swelling) in tissues perfused by the peripheral vascular system, usually in the lower limbs. In the most dependent parts of the body (those hanging distally), it may be called dependent edema. Cause The condition is commonly associated with vascular and cardiac changes associated with aging but can be caused by many other conditions, including congestive heart failure, kidney failure, liver cirrhosis, portal hypertension, trauma, alcoholism, altitude sickness, pregnancy, hypertension, sickle cell anemia, a compromised lymphatic system or merely long periods of time sitting or standing without moving. Some medicines (e.g. amlodipine, pregabalin) may also cause or worsen the condition. Prognosis Successful treatment depends on control of the underlying cause. Severe swelling can cause permanent damage to nerves, resulting in peripheral neuropathy Peripheral neuropathy, often shortened to neuropathy, refers to damage o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pulmonary Edema
Pulmonary edema (British English: oedema), also known as pulmonary congestion, is excessive fluid accumulation in the tissue or air spaces (usually alveoli) of the lungs. This leads to impaired gas exchange, most often leading to shortness of breath ( dyspnea) which can progress to hypoxemia and respiratory failure. Pulmonary edema has multiple causes and is traditionally classified as cardiogenic (caused by the heart) or noncardiogenic (all other types not caused by the heart). Various laboratory tests ( CBC, troponin, BNP, etc.) and imaging studies (chest x-ray, CT scan, ultrasound) are often used to diagnose and classify the cause of pulmonary edema. Treatment is focused on three aspects: * improving respiratory function, * treating the underlying cause, and * preventing further damage and allow full recovery to the lung. Pulmonary edema can cause permanent organ damage, and when sudden (acute), can lead to respiratory failure or cardiac arrest due to hypoxia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Congestive Heart Failure
Heart failure (HF), also known as congestive heart failure (CHF), is a syndrome caused by an impairment in the heart's ability to fill with and pump blood. Although symptoms vary based on which side of the heart is affected, HF typically presents with shortness of breath, excessive fatigue, and bilateral leg swelling. The severity of the heart failure is mainly decided based on ejection fraction and also measured by the severity of symptoms. Other conditions that have symptoms similar to heart failure include obesity, kidney failure, liver disease, anemia, and thyroid disease. Common causes of heart failure include coronary artery disease, heart attack, high blood pressure, atrial fibrillation, valvular heart disease, excessive alcohol consumption, infection, and cardiomyopathy. These cause heart failure by altering the structure or the function of the heart or in some cases both. There are different types of heart failure: right-sided heart failure, which affect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nasal Congestion
Nasal congestion is the partial or complete blockage of nasal passages, leading to impaired nasal breathing, usually due to membranes lining the nose becoming swollen from inflammation of blood vessels. Background In about 85% of cases, nasal congestion leads to mouth breathing rather than nasal breathing. According to Jason Turowski, MD of the Cleveland Clinic, "we are designed to breathe through our noses from birth—it's the way humans have evolved." This is referred to as " obligate nasal breathing." Nasal congestion can interfere with hearing and speech. Significant congestion may interfere with sleep, cause snoring, and can be associated with sleep apnea or upper airway resistance syndrome. In children, nasal congestion from enlarged adenoids has caused chronic sleep apnea with insufficient oxygen levels and hypoxia. The problem usually resolves after surgery to remove the adenoids and tonsils, however the problem often relapses later in life due to craniofacial ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prostatic Congestion
Prostatic congestion is a medical condition of the prostate gland that happens when the prostate becomes swollen by excess fluid and can be caused by prostatitis. The condition often results in a person with prostatic congestion feeling the urge to urinate frequently. Prostatic congestion has been associated with prostate disease, which can progress due to age. Oftentimes, the prostate will grow in size which can lead to further problems, such as prostatitis, enlarged prostate, or prostate cancer. Prostatic congestion is commonly observed in individuals between the ages of 20 and 40 years. It can however occur at any age. Chronic prostatitis is one of the main causes of this condition and this occurs when there is accumulation of fluid that can lead to swelling of the prostate that can therefore lead to congestion. Other possible causes of prostatic congestion include benign prostatic hyperplasia, prostate cancer, urinary tract cysts, and infrequent ejaculations. Symptoms are ofte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Network Congestion
Network congestion in data networking and queueing theory is the reduced quality of service that occurs when a network node or link is carrying more data than it can handle. Typical effects include queueing delay, packet loss or the blocking of new connections. A consequence of congestion is that an incremental increase in offered load leads either only to a small increase or even a decrease in network throughput. Network protocols that use aggressive retransmissions to compensate for packet loss due to congestion can increase congestion, even after the initial load has been reduced to a level that would not normally have induced network congestion. Such networks exhibit two stable states under the same level of load. The stable state with low throughput is known as congestive collapse. Networks use congestion control and congestion avoidance techniques to try to avoid collapse. These include: exponential backoff in protocols such as CSMA/CA in 802.11 and the similar CSMA/C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Traffic Congestion
Traffic congestion is a condition in transport that is characterized by slower speeds, longer trip times, and increased vehicular queueing. Traffic congestion on urban road networks has increased substantially since the 1950s, resulting in many of the roads becoming obsolete. When traffic demand is great enough that the interaction between vehicles slows the traffic stream, this results in congestion. While congestion is a possibility for any mode of transportation, this article will focus on automobile congestion on public roads. Mathematically, traffic is modeled as a flow through a fixed point on the route, analogously to fluid dynamics. As demand approaches the capacity of a road (or of the intersections along the road), extreme traffic congestion sets in. When vehicles are fully stopped for periods of time, this is known as a traffic jam or (informally) a traffic snarl-up or a tailback. Drivers can become frustrated and engage in road rage. Drivers and driver-focused r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
