Extra-planetary weather

Weather is not partial to just planetary bodies, however. A star's corona is constantly being lost to space, creating what is essentially a very thin atmosphere throughout the solar system, known as the solar wind.

Inconsistencies in this wind and larger events on the surface of the star, such as Coronal Mass Ejections, form a system that has features analogous to conventional weather systems i.e. pressure and wind, and though not true weather, is usually known as space weather. The activity of this system can affect planetary atmospheres and occasionally surfaces. The interface of the solar wind with the terrestrial atmosphere can produce spectacular aurorae, but can play havoc with electrically sensitive systems such as electricity grids and radio signals.

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Pitch

In music, pitch is the psychological associate of the fundamental frequency of a note. The note an above middle C played on any instrument is perceived to be of the same pitch as a pure tone of 440 Hz, but does not essentially contain a partial having that frequency. Furthermore, a slight change in frequency need not lead to a perceived change in pitch, but a change in pitch implies a change in frequency. In fact, the just perceptible difference is about five cents, but varies over the range of hearing and is more precise when the two pitches are played at the same time. Like other human stimuli, the perception of pitch also can be explained by the Weber-Fechner law.

Pitch also depends on the amplitude of the sound, especially at low frequencies. For instance, a low bass note will sound lower in pitch if it is louder. Like other senses, the comparative perception of pitch can be fooled, resulting in "audio illusions". There are several of these, such as the tritone paradox, but most especially the Shepard scale, where a continuous or discrete sequence of specially formed tones can be made to sound as if the sequence continues ascending or descending forever.

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Heat wave

A heat wave is a prolonged period of extremely hot weather, which may be accompanied by high humidity. There is no universal definition of a heat wave the term is relative to the usual weather in the area. Temperatures that people from a hotter climate believe normal can be termed a heat wave in a cooler area if they are outside the normal climate pattern for that area. The term is applied both to routine weather variation and to extraordinary spells of heat which may occur only once a century. Severe heat waves have caused catastrophic crop failures, thousands of deaths from hyperthermia, and widespread power outages due to increased use of air conditioning.

Heat waves often occur for the period of the Dog Days of summer; indeed the French term canicule, denoting the general phenomenon of a heat wave, derives from the Italian canicula applied to the star Sirius, also known as the "Dog Star."

Some regions of the globe are more susceptible to heat waves than others, such as Mediterranean-type climates with a summer dry spell which becomes much hotter than usual during certain years

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Solar System

The Solar System, is the stellar system comprising the Sun and the retinue of celestial objects gravitationally bound to it: the eight planets, their 162 known moons, three currently identified dwarf planets and their four known moons, and thousands of small bodies. This last category includes asteroids, meteoroids, comets, and interplanetary dust.

The principal component of the Solar System is the Sun ; a main sequence G2 star that contains 99.86% of the system's known mass and dominates it gravitationally. Because of its large mass, the Sun has an interior density high enough to sustain nuclear fusion, releasing enormous amounts of energy, most of which is radiated into space in the form of electromagnetic radiation, including visible light. The Sun's two largest orbiting bodies, Jupiter and Saturn, account for more than 90% of the system's remaining mass.

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Unusual Twinnings

There are some patterns of twinning that are exceedingly rare: while they have been reported to happen, they are so unusual that most obstetricians or midwives may go their entire careers without encountering a single case.Among fraternal twins, in rare cases, the eggs are fertilized at different times with two or more acts of sexual intercourse, either within one menstrual cycle or, even more rarely, later on in the pregnancy . This can lead to the possibility of a woman carrying fraternal twins with different fathers . This phenomenon is known as heteropaternal superfecundation. One 1992 study estimates that the frequency of heteropaternal superfecundation among dizygotic twins whose parents were involved in paternity suits was approximately 2.4%; see the references section, below, for more details.

Among monozygotic twins, in extremely rare cases, twins have been born with opposite sexes . The probability of this is so vanishingly small that multiples having different genders is universally accepted as a sound basis for a clinical determination that in utero multiples are not monozygotic. When monozygotic twins are born with different genders it is because of chromosomal birth defects. In this case, although the twins did come from the same egg, it is incorrect to refer to them as genetically identical, since they have different karyotypes.

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Alternative education

Alternative education, also known as non-traditional education or educational alternative, describes a number of approaches to teaching and learning other than traditional publicly- or privately-run schools. These approaches can be applied to all students of all ages, from infancy to adulthood, and all levels of education.

Educational alternatives often are the result of education reform and are rooted in various philosophies that are fundamentally different from those of mainstream compulsory education. While some have strong political, scholarly, or philosophical orientations, others are more informal associations of teachers and students somehow dissatisfied with certain aspects of mainstream education.

Educational alternatives, which include charter schools, alternative schools, independent schools, and home-based learning vary widely, but often emphasize the value of small class size, close relationships between students and teachers, and a sense of community.

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Conjoined twins

Conjoined twins, are monozygotic twins, whose bodies are joined together at birth. This occurs where the single zygote of identical twins fails to separate completely, and the zygote starts to split after day 13 following fertilization. This condition occurs in about 1 in 50,000 human pregnancies. Most conjoined twins are now evaluated for surgery to attempt to separate them into separate functional bodies. The degree of difficulty rises if a vital organ or structure is shared between twins, such as brain, heart or liver.

A chimera is an ordinary person or animal except that some of his or her parts actually came from his or her twin. A chimera may arise either from identical twin fetuses,or from dizygotic fetuses, which can be identified by chromosomal comparisons from various parts of the body. The number of cells derived from each fetus can vary from one part of the body to another, and often leads to characteristic mosaicism skin colouration in human chimeras. A chimera may be a hermaphrodite, composed of cells from a male twin and a female twin.

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Tourism

Tourism is the act of travel for the purpose of recreation and business, and the provision of services for this act. Tourists are people who are "travelling to and staying in places outside their usual environment for not more than one consecutive year for leisure, business and other purposes not related to the exercise of an activity remunerated from within the place visited . The distance between these two places is of no significance.

A more comprehensive definition would be that tourism is a service industry, comprising a number of tangible and intangible components. The tangible elements include transport systems — air, rail, road, water and now, space; hospitality services — accommodation, foods and beverages, tours, souvenirs; and related services such as banking, insurance and safety and security. The intangible elements include: rest and relaxation, culture, escape, adventure, new and different experiences.
Many countries depend heavily upon travel expenditures by foreigners as a source of taxation and as a source of income for the enterprises that sell export services to these travellers. Consequently the development of tourism is often a strategy employed either by a Non-governmental organization NGO or a governmental agency to promote a particular region for the purpose of increasing commerce through exporting goods and services to non-locals.

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Immunology

Immunology is a broad branch of biomedical science that covers the study of all aspects of the immune system in all organisms. It deals with, among other things, the physiological functioning of the immune system in states of both health and disease; malfunctions of the immune system in immunological disorders autoimmune diseases, hypersensitivities, immune deficiency, allograft rejection; the physical, chemical and physiological characteristics of the components of the immune system in vitro, in situ, and in vivo. Immunology has various applications in several disciplines of science, and as such is further divided.

Classical immunology ties in with the fields of epidemiology and medicine. It studies the relationship between the body systems, pathogens, and immunity. The earliest written mention of immunity can be traced back to the plague of Athens in 430 BCE. Thucydides noted that people who had recovered from a previous bout of the disease could nurse the sick without contracting the illness a second time. Many other ancient societies have references to this phenomenon, but it was not until the 19th and 20th centuries before the concept developed into scientific theory.

The study of the molecular and cellular components that comprise the immune system, including their function and interaction, is the central science of immunology. The immune system has been divided into a more primitive innate immune system, and acquired or adaptive immune system of vertebrates, the latter of which is further divided into humoral and cellular components.

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Music

Music is an art, entertainment, or other human activity that involves organized and audible sounds and silence. It is expressed in terms of pitch, rhythm, harmony, and timbre. Music involves complex generative forms in time through the construction of patterns and combinations of natural stimuli, principally sound. As a human activity, music may be used for artistic or aesthetic, communicative, entertainment, or ceremonial purposes. The definition of what constitutes music varies according to culture and social context.

The broadest definition of music is organized sound. There are observable patterns to what is broadly labeled music, and while there are understandable cultural variations, the properties of music are the properties of sound as perceived and processed by humans.A more conservative definition would be: Music is harmonious sound created by the playing of instruments as a whole or individually. It is a direct expression of human emotions designed to manipulate and transform the emotion of the listener/listeners. Music is designed to be felt unlike sound which is heard.



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