In thermodynamics, the enthalpy of fusion of a substance, also known as (latent) heat of fusion, is the change in its enthalpy resulting from providing energy, typically heat, to a specific quantity of the substance to change its state from a solid to a liquid, at constant pressure. It is the amount of energy required to convert one mole of solid into liquid. For example, when melting 1 kg of ice (at 0 °C under a wide range of pressures), 333.55 kJ of energy is absorbed with no temperature change. The heat of solidification (when a substance changes from liquid to solid) is equal and opposite. This energy includes the contribution required to make room for any associated change in volume by displacing its environment against ambient pressure. The temperature at which the phase transition occurs is the melting point or the freezing point, according to context. By convention, the pressure is assumed to be 1 atm (101.325 kPa) unless otherwise specified. Overview The 'enthalpy' of fusion is a latent heat, because, while melting, the heat energy needed to change the substance from solid to liquid at...

Negative affectivity (NA), or negative affect, is a personality variable that involves the experience of negative emotions and poor self-concept. Negative affectivity subsumes a variety of negative emotions, including anger, contempt, disgust, guilt, fear, and nervousness. Low negative affectivity is characterized by frequent states of calmness and serenity, along with states of confidence, activeness, and great enthusiasm. Individuals differ in negative emotional reactivity. Trait negative affectivity roughly corresponds to the dominant personality factor of anxiety/neuroticism that is found within the Big Five personality traits as emotional stability. The Big Five are characterized as openness, conscientiousness, extraversion, agreeableness, and neuroticism. Neuroticism can plague an individual with severe mood swings, frequent sadness, worry, and being easily disturbed, and predicts the development and onset of all "common" mental disorders. Research shows that negative affectivity relates to different classes of variables: Self-reported stress and (poor) coping skills, health complaints, and frequency of unpleasant events. Weight gain and mental health...

The French Academy of Sciences (French: Académie des sciences) is a learned society, founded in 1666 by Louis XIV at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French scientific research. It was at the forefront of scientific developments in Europe in the 17th and 18th centuries, and is one of the earliest Academies of Sciences. Currently headed by Patrick Flandrin (President of the Academy), it is one of the five Academies of the Institut de France. History The Academy of Sciences traces its origin to Colbert's plan to create a general academy. He chose a small group of scholars who met on 22 December 1666 in the King's library, near the present-day Bibliothèque Nationals, and thereafter held twice-weekly working meetings there in the two rooms assigned to the group. The first 30 years of the Academy's existence were relatively informal, since no statutes had as yet been laid down for the institution. In contrast to its British counterpart, the Academy was founded as an organ of government. In Paris, there weren't many membership openings,...

In the Marxist theory of historical materialism, a mode of production (German: Produktionsweise, "the way of producing") is a specific combination of the: Productive forces: these include human labour power and means of production (tools, machinery, factory buildings, infrastructure, technical knowledge, raw materials, plants, animals, exploitable land). Social and technical relations of production: these include the property, power and control relations (legal code) governing the means of production of society, cooperative work associations, relations between people and the objects of their work, and the relations among the...

Mount Kilimanjaro () is a dormant volcano located in Kilimanjaro Region of Tanzania. It has three volcanic cones: Kibo, Mawenzi, and Shira. It is the highest mountain in Africa and the highest single free-standing mountain above sea level in the world: 5,895 metres (19,341 ft) above sea level and about 4,900 metres (16,100 ft) above its plateau base. It is the highest volcano in Africa and the Eastern Hemisphere. Kilimanjaro is the fourth most topographically prominent peak on Earth. It is part of Kilimanjaro National Park and is a major hiking and climbing destination. Because of its shrinking glaciers and ice fields, which are projected to disappear between 2025 and 2035, it has been the subject of many scientific studies. Toponymy The origin of the name Kilimanjaro is not known, but a number of theories exist. European explorers had adopted the name by 1860 and reported that Kilimanjaro was the mountain's Kiswahili name. The 1907 edition of The Nuttall Encyclopædia also records the name of the mountain as Kilima-Njaro.Johann Ludwig Krapf wrote in 1860 that Swahilis...