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2 天前 · Poliomyelitis (/ ˌ p oʊ l i oʊ ˌ m aɪ ə ˈ l aɪ t ɪ s / POH-lee-oh-MY-ə-LY-tiss), commonly shortened to polio, is an infectious disease caused by the poliovirus. Approximately 75% of cases are asymptomatic; mild symptoms which can occur include sore throat and fever; in a proportion of cases more severe symptoms develop such as headache, neck stiffness, and paresthesia.
- Fever, sore throat
- No treatment other than supportive care
5 天前 · Estimates of world population by their nature are an aspect of modernity, possible only since the Age of Discovery.Early estimates for the population of the world date to the 17th century: William Petty, in 1682, estimated the world population at 320 million (current estimates ranging close to twice this number); by the late 18th century, estimates ranged close to one billion (consistent with ...
2 天前 · Borderline personality disorder (BPD), also known as emotionally unstable personality disorder (EUPD),[16] is a personality disorder characterized by a pervasive, long-term pattern of significant interpersonal relationship instability, a distorted sense of self, and intense emotional responses.[9][17][18] Individuals diagnosed with BPD ...
- Genetics, trauma
- Early adulthood
- Suicide, self harm
- Behaviour therapy
3 天前 · The number π (/ p aɪ /; spelled out as "pi") is a mathematical constant that is the ratio of a circle's circumference to its diameter, approximately equal to 3.14159.The number π appears in many formulae across mathematics and physics.It is an irrational number, meaning that it cannot be expressed exactly as a ratio of two integers, although fractions such as are commonly used to ...
6 天前 · In physical cosmology, cosmic inflation, cosmological inflation, or just inflation, is a theory of exponential expansion of space in the early universe. The inflationary epoch is believed to have lasted from 10 −36 seconds to between 10 −33 and 10 −32 seconds after the Big Bang. Following the inflationary period, the universe continued to ...
2 天前 · Etymology and nomenclature The name Generation Z is a reference to the fact that it is the second generation after Generation X, continuing the alphabetical sequence from Generation Y (Millennials). Other proposed names for the generation included iGeneration, Homeland Generation, Net Gen, Digital Natives, Neo-Digital Natives, Pluralist Generation, Internet Generation, Centennials, and Post ...
5 天前 · Principal component analysis (PCA) is a linear dimensionality reduction technique with applications in exploratory data analysis, visualization and data preprocessing. The data is linearly transformed onto a new coordinate system such that the directions (principal components) capturing the largest variation in the data can be easily identified.
