In mathematics, the slope or gradient of a line is a number that describes both the direction and the steepness of the line. Slope is denoted by the letter m. Slope is calculated by finding the ratio of the "vertical change" to the "horizontal change" between two distinct points on a line. Sometimes the ratio is expressed as a quotient, giving the same number for every two distinct points on the same line. A line, decreasing has a negative "rise"; the line may be practical - as set by a road surveyor, or in a diagram that models a road or a roof either as a description or as a plan. The steepness, incline, or grade of a line is measured by the absolute value of the slope. A slope with a greater absolute value indicates a steeper line; the direction of a line is either increasing, horizontal or vertical. A line is increasing; the slope is positive, i.e. m > 0. A line is decreasing; the slope is negative, i.e. m < 0. If a line is horizontal the slope is zero; this is a constant function. If a line is vertical the slope is undefined.

The rise of a road between two points is the difference between the altitude of the road at those two points, say y1 and y2, or in other words, the rise is = Δy. For short distances - where the earth's curvature may be neglected, the run is the difference in distance from a fixed point measured along a level, horizontal line, or in other words, the run is = Δx. Here the slope of the road between the two points is described as the ratio of the altitude change to the horizontal distance between any two points on the line. In mathematical language, the slope m of the line is m = y 2 − y 1 x 2 − x 1; the concept of slope applies directly to gradients in geography and civil engineering. Through trigonometry, the slope m of a line is related to its angle of incline θ by the tangent function m = tan ⁡ Thus, a 45° rising line has a slope of +1 and a 45° falling line has a slope of −1; as a generalization of this practical description, the mathematics of differential calculus defines the slope of a curve at a point as the slope of the tangent line at that point.

When the curve is given by a series of points in a diagram or in a list of the coordinates of points, the slope may be calculated not at a point but between any two given points. When the curve is given as a continuous function as an algebraic formula the differential calculus provides rules giving a formula for the slope of the curve at any point in the middle of the curve; this generalization of the concept of slope allows complex constructions to be planned and built that go well beyond static structures that are either horizontals or verticals, but can change in time, move in curves, change depending on the rate of change of other factors. Thereby, the simple idea of slope becomes one of the main basis of the modern world in terms of both technology and the built environment; the slope of a line in the plane containing the x and y axes is represented by the letter m, is defined as the change in the y coordinate divided by the corresponding change in the x coordinate, between two distinct points on the line.

This is described by the following equation: m = Δ y Δ x = vertical change horizontal change = rise run. Given two points and, the change in x from one to the other is x2 − x1, while the change in y is y2 − y1. Substituting both quantities into the above equation generates the formula: m = y 2 − y 1 x 2 − x 1; the formula fails for a vertical line, parallel to the y axis, where the slope can be taken as infinite, so the slope of a vertical line is considered undefined. Suppose a line runs through two points: P = and Q =. By dividing the difference in y-coordinates by the difference in x-coordinates, one can obtain the slope of the line: m = Δ y Δ x = y 2 − y 1 x 2 − x 1 = 8 − 2 13 − 1 = 6 12 = 1 2 {\displaystyle m={\frac {\Delt

Glossary of virology

This glossary of virology is a list of definitions of terms and concepts used in the study of virology in the description of viruses and their actions. Animal virus Any virus capable of infecting one or more animal species. Antigenic drift antigenic shift antiviral drug Often called an antiviral. A class of antimicrobial medication used for treating diseases caused by viral infections rather than ones caused by bacteria or other infectious agents. Unlike most antibiotics, antivirals do not destroy their target viruses but instead inhibit their development, they are distinct from virucides. Assembly The construction of the virus within the host cell, using the host's metabolism. Attachment bacteriophage Also called a phage. Any virus that infects and replicates within bacteria or archaea. Baltimore classification base pair cap cap snatching capsid The outer shell of protein that encloses and protects the genetic material of a virus. Capsomere A subunit of the viral capsid which self-assembles with other capsomeres to form the capsid.

Co-option coinfection complex cytopathic effect dalton A unit of length used to describe the size of a virus or viral particle. DNA virus A type of virus that has DNA as its genetic material and replicates using a DNA-dependent DNA polymerase. In the Baltimore classification system, DNA viruses belong to either Group I or Group II. DsDNA virus dsDNA-RT virus dsRNA virus ecovirology emergent virus endogenous viral element entry enveloped giant virus A large virus one of the so-called nucleocytoplasmic large DNA viruses, which have large genomes compared to the average virus and contain many unique genes not found in other organisms; some of these viruses are larger than a typical bacterium. Global Virus Network group-specific antigen Also called a gag. helical helper dependent virus helper virus host host tropism The specificity with which certain pathogens, including most viruses, infect particular hosts and host tissues. Host tropism results in most pathogens being capable of infecting only a limited range of host organisms.

Human Immunodeficiency Virus icosahedral Having the symmetry of an icosahedron. Inclusion body integrase. Latency 1; the ability of a pathogenic virus to lie dormant or latent within a cell for a period of time before reactivating and producing new, independent virions. 2. The phase in the life cycle of certain viruses in which, after initial infection, proliferation of virus particles ceases while the viral genome remains silently assimilated into the host cell's genome, sometimes indefinitely; the latent period ends when the virus reactivates and begins producing large amounts of viral progeny without the host cell being infected by additional external virions. Latency is a defining element of the lysogenic form of viral replication. Live virus reference strain lysogenic cycle lytic cycle maturation molecular virology multiplicity of infection mycovirus Also sometimes called a mycophage. Any virus capable of infecting one or more species of fungi. Nanometer A unit of length used to describe the size of a virus or viral particle.

One nanometer is equal to 10−9 meter. Negative-sense ssRNA virus neurotropic virus neurovirology novel virus nucleocapsid nucleotide oncovirus original antigenic sin orphan virus paleovirology parasite passenger virus A virus, found in samples from diseased tissue, such as tumors, but does not contribute to causing the disease. Penetration phenotype mixing plant virus Any virus capable of infecting one or more plant species. Positive-sense ssRNA virus prolate prophage provirus pseudotyping Q-number reassortment recombinant virus release rep An abbreviation for replication protein. Replication Any of the various processes by. Retrovirus reverse transcriptase RNA interference RNA virus rolling circle replication satellite sense serial passage slow virus Any virus or virus-like agent, etiologically associated with a so-called slow virus disease: a disease which, after an extended period of latency, follows a slow, progressive course ranging from months to years before in most cases progressing to death.

SsDNA virus ssRNA-RT virus strain subviral agent superinfection synthetic virology T-number temperate tissue tropism transduction triangulation number uncoating virological failure virologic failure occurs when antiviral therapy fails to suppress and sustain a person's viral load under a predetermined threshold. Viral culture viral disease Any disease that occurs when an organism's body is invaded by infectious viral particles of one or more pathogenic viruses which attach to, parasitize susceptible cells. Viral dynamics viral envelope A lipid casing present in some viruses which surrounds the capsid and helps to penetrate the host's cell wall. Viral load viral matrix viral particle See virion. Viral plaque viral protein viral shedding viral transformation viral vector viremia virion Also called a viral particle. A singular, stable particle, the independent form in which a virus exists while not inside an infected cell or in the process of infecting a cell. Virions are the products of a completed viral replication cycle.

Viroid viroinformatics virokine virology The study of viruses and virus-like agents, which seeks to understand and explain their structure, evolution, m

Mats Ronander

Mats Ronander is a Swedish rock musician, guitar player and composer. Ronander was born in Sundsvall, but grew up in Örebro. At the age of sixteen he succeeded Peps Persson as singer in the band Blues Quality, he was a member of the band Nature. The band backed up Ulf Lundell on a tour and three of Lundell's studio album as well as released a few records of their own. Mats Ronander has played live with ABBA on several occasions, as one of their guitarists, such as on their 1979 world tour; the 1992 single "Gör mig lycklig nu" and the album Himlen gråter för Elmore James produced by Mats Ronander, Mats Lindfors and Max Lorentz were Ronander's most successful solo projects. Ronander was a member of Low budget blues band that released three albums, he was a member of Grymlings. Ronander produced Py Bäckman's breakthrough record Sista föreställningen, toured with ABBA in United States, starred in the screen adaption of Ulf Lundell's novel Sömnen. Hård kärlek 1981 God bok 1982 50/50 1984 Tokig 1985 Reality 1987 Rock'n'roll Biznis 1989 Himlen gråter för Elmore James 1992 Svenska popfavoriter Mats Ronander 1995 Innanför staden 1996 Mats 2001 Bästa 2003 Ronander Live 2006 Dödlig drift 1999 "Gör mig lycklig nu" 1992 Official website Mats Ronander on IMDb