This article possibly contains original research .(January 2024) |
Mixing patterns refer to systematic tendencies of one type of nodes in a network to connect to another type. For instance, nodes might tend to link to others that are very similar or very different. This feature is common in many social networks, although it also appears sometimes in non-social networks. Mixing patterns are closely related to assortativity; however, for the purposes of this article, the term is used to refer to assortative or disassortative mixing based on real-world factors, either topological or sociological.
Mixing patterns are a characteristic of an entire network, referring to the extent for nodes to connect to other similar or different nodes. Mixing, therefore, can be classified broadly as assortative or disassortative. Assortative mixing is the tendency for nodes to connect to like nodes, while disassortative mixing captures the opposite case in which very different nodes are connected.
Obviously, the particular node characteristics involved in the process of creating a link between a pair will shape a network's mixing patterns. For instance, in a sexual relationship network, one is likely to find a preponderance of male-female links, while in a friendship network male-male and female-female networks might prevail. Examining different sets of node characteristics thus may reveal interesting communities or other structural properties of the network. In principle there are two kinds of methods used to exploit these properties. One is based on analytical calculations by using generating function techniques. The other is numerical, and is based on Monte Carlo simulations for the graph generation. [1]
In a study on mixing patterns in networks, M.E.J. Newman starts by classifying the node characteristics into two categories. While the number of real-world node characteristics is virtually unlimited, they tend to fall under two headings: discrete and scalar/topological. The following sections define the differences between the categories and provide examples of each. For each category, the models of assortatively mixed networks introduced by Newman are discussed in brief.
A common application of mixing patterns is the study of disease transmission. For instance, many studies have used mixing to study the spread of HIV/AIDS and other contagious diseases. [2] [3] [4] These articles find a strong connection between Mixing patterns and the rate of disease spread. The findings can also be used to model real-world network growth, as in, [5] or find communities within networks.
Disassortative mating is a mating pattern in which individuals with dissimilar phenotypes mate with one another more frequently than would be expected under random mating. Disassortative mating reduces the mean genetic similarities within the population and produces a greater number of heterozygotes. The pattern is character specific, but does not affect allele frequencies. This nonrandom mating pattern will result in deviation from the Hardy-Weinberg principle.
In mathematics, computer science and network science, network theory is a part of graph theory. It defines networks as graphs where the vertices or edges possess attributes. Network theory analyses these networks over the symmetric relations or asymmetric relations between their (discrete) components.
Assortative mating is a mating pattern and a form of sexual selection in which individuals with similar phenotypes or genotypes mate with one another more frequently than would be expected under a random mating pattern. A majority of the phenotypes that are subject to assortative mating are body size, visual signals, and sexually selected traits such as crest size. The opposite of assortative is disassortative mating.
In the study of complex networks, assortative mixing, or assortativity, is a bias in favor of connections between network nodes with similar characteristics. In the specific case of social networks, assortative mixing is also known as homophily. The rarer disassortative mixing is a bias in favor of connections between dissimilar nodes.
Assortativity, or assortative mixing, is a preference for a network's nodes to attach to others that are similar in some way. Though the specific measure of similarity may vary, network theorists often examine assortativity in terms of a node's degree. The addition of this characteristic to network models more closely approximates the behaviors of many real world networks.
Odynorgasmia, or painful ejaculation, also referred to as dysejaculation, dysorgasmia, and orgasmalgia, is a physical syndrome described by pain or burning sensation of the urethra or perineum during or following ejaculation. Causes include: infections associated with urethritis, prostatitis, epididymitis; use of anti-depressants; cancer of the prostate or of other related structures; calculi or cysts obstructing related structures; trauma to the region.
Amelanotic melanoma is a type of skin cancer in which the cells do not make any melanin. They can be pink, red, purple or of normal skin color, and are therefore difficult to diagnose correctly. They can occur anywhere on the body, just as a typical melanoma can.
Gonorrhoea or gonorrhea, colloquially known as the clap, is a sexually transmitted infection (STI) caused by the bacterium Neisseria gonorrhoeae. Infection may involve the genitals, mouth, or rectum. Infected men may experience pain or burning with urination, discharge from the penis, or testicular pain. Infected women may experience burning with urination, vaginal discharge, vaginal bleeding between periods, or pelvic pain. Complications in women include pelvic inflammatory disease and in men include inflammation of the epididymis. Many of those infected, however, have no symptoms. If untreated, gonorrhea can spread to joints or heart valves.
Multifocal lymphangioendotheliomatosis, also known as congenital cutaneovisceral angiomatosis with thrombocytopenia and multifocal lymphangioendotheliomatosis with thrombocytopenia (MLT), is a skin condition that presents at birth with hundreds of red-brown plaques as large as several centimeters.
Pincer nails are a toenail disorder in which the lateral edges of the nail slowly approach one another, compressing the nailbed and underlying dermis. It occurs less often in the fingernails than toenails, and there usually are no symptoms.
Malignant acrospiroma, also known as nodular hidradenocarcinoma, malignant nodular clear-cell hidradenoma, mucoepidermoid hidradenocarcinoma, clear-cell hidradenocarcinoma, malignant clear-cell acrospiroma, and clear-cell eccrine carcinoma, is a rare and aggressive tumour of the eccrine sweat glands. It was first documented by Keasbey and Hadley in 1954.
Indeterminate cell histiocytosis(LCH) is an uncommon proliferative illness where the predominant cells have characteristics from both non-Langerhans cell histiocytosis (NLCH) and Langerhans cell histiocytosis (LCH) in terms of morphology and immunophenotypic characteristics. Wood et al. originally described ICH in 1985 as a neoplastic disease arising from dermal indeterminate cells that lack Birbeck granules but are characteristically positive for S-100 and CD1a.
Malignant pilomatricoma is a cutaneous condition characterized by a locally aggressive tumor composed of hair-matrix cells.
Airbag dermatitis is skin irritation secondary to the deployment of airbags. The diagnosis of "air bag dermatitis" is relatively recent; the first case was reported in 1994.
Pulmonary vein stenosis is a rare cardiovascular disorder. It is recognized as being the stenosis of one or more of the four pulmonary veins that return blood from the lungs to the left atrium of the heart. In congenital cases, it is associated with poor prognosis and high mortality rate. In some people, pulmonary vein stenosis occurs after pulmonary vein ablation for the treatment of atrial fibrillation. Some recent research has indicated that it may be genetically linked in congenital cases.
Rectal douching is the act of rinsing the rectum with intent to clean it. An instance of this rinsing or a tool used to perform the rinse may be called a rectal douche.
Centrilobular necrosis (CN) is a nonspecific histopathological observation brought on by hepatotoxins like acetaminophen (paracetamol), thioacetamide, tetrachloride, cardiac hepatopathy due to acute right sided cardiac failure, and congestive hepatic injury in veno‐occlusive disease, or hypoxic injury due to ischemia. Centrilobular necrosis can also be found in those with autoimmune hepatitis. Centrilobular necrosis is characterized by necrotic hepatocytes completely encircling the central vein.
David DuPuy Celentano is a noted epidemiologist and professor who has contributed significantly to the promotion of research on HIV/AIDS and other sexually transmitted infections (STIs). He is the Charles Armstrong chair of the Department of Epidemiology at the Johns Hopkins Bloomberg School of Public Health. He holds joint appointments with the school’s departments of Health Policy and Management, Health Behavior and Society, and International Health, and the Johns Hopkins University School of Medicine’s Division of Infectious Diseases.
Willard Cates Jr. was an American epidemiologist and public health advocate known for his work on HIV/AIDS and women's health. In 1974, he began working at the Epidemic Intelligence Service of the Centers for Disease Control and Prevention (CDC), where he researched the epidemiology of abortion. He served as director of the CDC's Division of Sexually Transmitted Diseases from 1982 to 1992. In 1994, he began working at FHI 360, where he became president of the Institute for Family Health in 1998. He was a member of the Institute of Medicine and served as president of both the Society for Epidemiologic Research and the Association of Reproductive Health Professionals.
William Wallace (1791-1837), was an Irish surgeon at the Jervis Street Hospital, Dublin, who used potassium iodide to treat syphilis, and experimented on healthy individuals by inoculating them with syphilis to demonstrate it was contagious. In 1818 he founded the Dublin Infirmary for Diseases of the Skin at 20 Moore Street. He wrote A Treatise on the Venereal Disease and Its Varieties (1833).