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Spiders

Spiders   Reference library

The New Encyclopedia of Insects and their Allies (3 rev. ed.)

Reference type:
Subject Reference
Current Version:
2009
Subject:
Science and technology, Life Sciences
Length:
8,259 words
Illustration(s):
11

...for 2–5 years, and theraphosids (tarantulas) in captivity may live up to 25 years. During a lifetime, they typically grow through 4–12 molts of the exoskeleton before finally becoming adult. Adult males can usually be distinguished from adult females by their smaller size, slimmer body, and relatively longer legs. This sexual dimorphism is most obvious in many tropical web‐builders, such as the golden orb‐weavers ( Nephila species), where the females may be giants – up to 45mm (1.8in) in body length – and the males are frequently a dwarfish 4–8mm (0.20.3in)....

magnetic moment

magnetic moment   Quick reference

A Dictionary of Electronics and Electrical Engineering (5 ed.)

Reference type:
Subject Reference
Current Version:
2018
Subject:
Science and technology, Engineering and Technology
Length:
277 words
Illustration(s):
3

...dipole moment ) ( symbol: m ; unit: ampere metre 2 ) A measure of the strength of a magnet . When a magnet is placed in a homogeneous magnetic flux of magnetic flux density B it experiences a torque T such that where m is the magnetic moment. If the magnet is a small coil of area d A carrying a current I , then the magnetic moment m is equal to I d A . 2. ( magnetic dipole moment ) ( symbol: p m ; unit: weber metre ) The product of magnetic moment m and the permeability of free space, μ 0 : Historically magnets and small circulating currents...

deserts

deserts   Reference library

The Oxford Companion to the Earth

Reference type:
Subject Reference
Current Version:
2003
Subject:
Science and technology, Earth Sciences and Geography
Length:
1,322 words
Illustration(s):
2

...Desert mountains 38.1 43.0 Playas 1.1 1.0 Desert flats 20.5 10.0 Bedrock fields 0.7 10.0 Regions bordering 1.2 1.0 through flowing rivers Ephemeral streams 3.6 1.0 Alluvial fans 31.4 1.0 Sand dunes 0.6 28.0 Badlands 2.6 2.0 Volcanic fields 0.2 3.0 The character of desert landforms is also affected strongly by the regional geological and tectonic environment. Two end-member models can be recognized (Table 1). The tectonically stable Old World shield deserts, such as those in the Arabian Peninsula, Australia, and southern Africa (Fig. 2a), are characterized by...

Scorpionflies

Scorpionflies   Reference library

The New Encyclopedia of Insects and their Allies (3 rev. ed.)

Reference type:
Subject Reference
Current Version:
2009
Subject:
Science and technology, Life Sciences
Length:
1,378 words
Illustration(s):
1

...true, or common, scorpionflies are widely distributed. About 15–20mm (0.6–0.8in) long, they are usually yellowish‐brown with brownish bands and spots on the wings. Panorpa communis is a very common species throughout Europe, with a wingspan of 30mm (1.2in). The snow scorpionflies, characterized by their vestigial wings, are found in Europe and North America, where they live and feed on moss. These unusual insects are often found on the surface of the snow in winter, and are 2–5mm (0.08–0.2in) long and dark‐colored. The hanging scorpionflies are so called for...

Nuclear Energy

Nuclear Energy   Reference library

Oxford Encyclopedia of the Modern World

Reference type:
Subject Reference
Current Version:
2008
Subject:
History, Contemporary History (post 1945)
Length:
3,681 words
Illustration(s):
1

...2 935 1 692 Armenia 1 376 0 0 Belgium 7 5,801 0 0 Brazil 2 1,901 0 0 Bulgaria 4 2,722 0 0 Canada 18 12,599 0 0 China 9 6,602 2 2,000 Czech Republic 6 3,528 0 0 Finland 4 2,676 1 1,600 France 59 63,363 0 0 Germany 17 20,339 0 0 Hungary 4 1,755 0 0 India 15 3,040 8 3,602 Iran 0 0 1 915 Japan 55 46,772 2 1,933 Korea, Republic of 20 16,810 0 0 Lithuania 1 1,185 0 0 Mexico 2 1,310 0 0 Netherlands 1 449 0 0 Pakistan 2 425 0 0 Romania 1 655 1 655 Russian Federation 31 21,743 4 3,775 Slovak Republic 6 2,442 0 0 Slovenia 1 656 0 0 South Africa 2 1,800 0 0 Spain...

Design of Discrete Choice Experiments

Design of Discrete Choice Experiments   Reference library

Deborah J. Street and Rosalie Viney

The Oxford Encyclopedia of Health Economics

Reference type:
Subject Reference
Current Version:
2020
Subject:
Social sciences, Economics
Length:
12,342 words
Illustration(s):
9

...Table 4. A Generator-Developed DCE From an OA[8; 2 4 , 4;2] Choice Set OA Option 2 Option 3 1 0 0 0 0 0 1 1 1 1 1 1 1 0 0 3 2 0 0 1 1 2 1 1 0 0 3 1 1 1 1 1 3 0 1 0 1 1 1 0 1 0 2 1 0 0 1 0 4 0 1 1 0 3 1 0 0 1 0 1 0 1 0 2 5 1 0 0 1 3 0 1 1 0 0 0 1 0 1 2 6 1 0 1 0 1 0 1 0 1 2 0 1 1 0 0 7 1 1 0 0 2 0 0 1 1 3 0 0 0 0 1 8 1 1 1 1 0 0 0 0 0 1 0 0 1 1 3 The easiest way to summarize the systematic changes is to represent them by a k -tuple of numbers, which is called a generator . This generator is added to each row of the OA in turn to get the next option in the...

Internet

Internet   Reference library

Oxford Encyclopedia of the Modern World

Reference type:
Subject Reference
Current Version:
2008
Subject:
History, Contemporary History (post 1945)
Length:
1,213 words
Illustration(s):
1

...Stephen . Nerds 2.0.1: A Brief History of the Internet . New York: TV Books, 1998. This engaging text appeared as the companion volume to a Public Broadcasting System series of the same name. Segaller is attentive to both shifting computer technologies and to the human relationships that shaped the early history of the Internet and personal computing more generally. Weinberger, David . Small Pieces Loosely Joined: A Unified Theory of the Web . Cambridge, Mass.: Perseus Pub., 2002. Though this text does not offer a unified theory of the “Web,” Weinberger does...

Sloan Digital Sky Survey

Sloan Digital Sky Survey   Reference library

The Oxford Companion to Cosmology

Reference type:
Subject Reference
Current Version:
2008
Subject:
Science and technology, Astronomy and Cosmology
Length:
1,136 words
Illustration(s):
1

...galaxy sample within a redshift z =0.2. The right plot shows 10 904 galaxies from the luminous red galaxy sample to z =0.5. Only a small fraction of all galaxies observed, those within a 2.5 degree wide stripe centred on the celestial equator, are plotted, as otherwise the clustering pattern is ‘washed out’ by projection. SDSS galaxy distribution Jon Loveday The survey telescope is situated at Apache Point Observatory, New Mexico, US. Survey hardware comprises the main 2.5-metre survey telescope, a 0.5-metre photometric telescope, a 120 mega-pixel...

Rotifers, or Wheel Animalcules

Rotifers, or Wheel Animalcules   Reference library

The Encyclopedia of Underwater Life

Reference type:
Subject Reference
Current Version:
2007
Subject:
Science and technology, Life Sciences
Length:
660 words
Illustration(s):
1

...of water and their populations may rise and fall rapidly. They are crucial members of numerous aquatic food webs. Soil-dwelling rotifers aid soil breakdown. Andrew Campbell Factfie-Rotifers, or Wheel Animalcules Phylum: Rotifera Classes: Monogononta, Digononta, Bdelloidea About 1,800 species in 100 genera and 3 classes. Distribution Worldwide, mainly freshwater, some marine, and damp soils. Fossil record None. Size Microscopic, 0.04–2mm (0.002–0.08in). Features Solitary or colonial; body cavity a pseudocoel (now described as blastocoelomate); head bears...

Platypus

Platypus   Reference library

The Encyclopedia of Mammals (3 ed.)

Reference type:
Subject Reference
Current Version:
2007
Subject:
Science and technology, Life Sciences
Length:
1,277 words
Illustration(s):
2

...female 39–55cm (15.4–21.7in); bill length average male 5.8cm (2.3in) female 5.2cm (2in); tail length male 10.5–15.2cm (4.1–6in) female 8.5–13cm (3.3–5.1in); weight male 1–2.4kg (2.2–5.3lb) female 0.7–1.6kg (1.5–3.5lb). Coat Dark brown back, silver to light brown underside with rust brown midline, especially in young animals, which have the lightest fur. Short, dense fur (about 1cm/0.4in depth). Light patch below eye/ear groove. Breeding Gestation period not known (probably 2–3 weeks). Incubation not known (probably about 10 days). Longevity 10 or...

particle accelerators

particle accelerators   Reference library

The Oxford Companion to Cosmology

Reference type:
Subject Reference
Current Version:
2008
Subject:
Science and technology, Astronomy and Cosmology
Length:
670 words
Illustration(s):
2

...decay is shown in Fig. 2, in this case being the decay of a Z 0 boson ( See standard model of particle physics ) which would have been created shortly before in an electron–positron collision. Particles in an accelerator can be travelling very close to the speed of light, perhaps 99.99% of it. Relativity theory is therefore required and is routinely tested in accelerator operation. Fig. 1. Aerial view of the CERN accelerator ring on the Swiss–French border, with its position highlighted. Fig. 2. The decay of a Z 0 boson as witnessed by the...

Albers, Josef

Albers, Josef (19 March 1888)   Reference library

The Grove Encyclopedia of American Art

Reference type:
Subject Reference
Current Version:
2011
Subject:
Art & Architecture
Length:
1,414 words
Illustration(s):
1

...Spies and others, Düsseldorf, Städt. Ksthalle, 1970) J. Miller : Joseph Albers: Prints, 1915–1970 (New York, 1973) N. F. Weber : The Drawings of Josef Albers (New Haven, 1984) N. D. Benezra : The Murals and Sculpture of Josef Albers (New York, 1985) G. Alviani : Josef Albers (Milan, 1988) [English, German, and Italian] Josef Albers: A Retrospective (exh. cat. by N. F. Weber and others, New York, Guggenheim, 1988) N. F. Weber : Josef and Anni Albers: Designs for Living (London, 2004) B. Danilowitz and H. Liesbrock : Anni and Josef Albers: Latin...

Stoneflies

Stoneflies   Reference library

The New Encyclopedia of Insects and their Allies (3 rev. ed.)

Reference type:
Subject Reference
Current Version:
2009
Subject:
Science and technology, Life Sciences
Length:
963 words
Illustration(s):
1

...important part of the freshwater food web, providing food for many other insects and fish. Since stoneflies are very sensitive to pollution, they are used by scientists as indicators of water quality. Factfile‐Stoneflies Class: Insecta Subclass: Neoptera Order: Plecoptera 2,000 species in 15 families, divided between 2 suborders: Arctoperlaria (11 families) and Antarctoperlaria (4 families). DISTRIBUTION Worldwide except Antarctica, especially in temperate climes. SIZE Delicate, medium‐sized; body length 3–50mm (0.1–2in). FEATURES Cylindrical body,...

psychophysics

psychophysics   Reference library

The Oxford Companion to the Mind (2 ed.)

Reference type:
Subject Reference
Current Version:
2006
Subject:
Science and technology, Psychology, Philosophy
Length:
1,586 words
Illustration(s):
1

...method of measuring sensations. If a luminance L 2 can just be distinguished as greater than L 1 , then, to a close approximation, L 2 / L 1 is constant; this is Weber's law (formulated as the Weber–Fechner law). If one supposes that all just-noticeable differences (e.g. between L 1 and L 2 ) are subjectively equivalent, then the sensation (in this case, of brightness) must increase as the logarithm of the physical stimulus magnitude, for if L 2 / L 1 , is constant, so also is log L 2 − log L 1 . Fechner's logarithmic measure was...

Limpkin

Limpkin   Reference library

The New Encyclopedia of Birds

Reference type:
Subject Reference
Subject:
Science and technology, Life Sciences
Length:
635 words
Illustration(s):
3

...arid brush (as in W Indies). Size Length 56–71cm (22–28in); weight 0.9–1.3kg (22.9lb). Plumage Dark olive-brown with bronze to greenish iridescence on upperparts, foreparts broadly streaked with white; sexes alike. Voice Noisy; loud wails, screams, and assorted clucks, heard mostly at night. Nest Shallow, made of rushes or sticks just above the waterline in marshes, or else in bushes or trees. Eggs Usually 5–7, pale buff, blotched and speckled with light brown; average size 60 x 44mm (2.4 x 1.7in). Incubation about 27 days. Diet Mainly large snails and...

Booklice and Webspinners

Booklice and Webspinners   Reference library

The New Encyclopedia of Insects and their Allies (3 rev. ed.)

Reference type:
Subject Reference
Current Version:
2009
Subject:
Science and technology, Life Sciences
Length:
1,200 words
Illustration(s):
2

...species in 8 families. Size: Small to medium‐sized; 5–12mm (0.20.5in) long. Features: Elongated, cylindrical body adapted for living in tubular silk tunnels; antennae with 12–32 segments; eyes kidney‐shaped; no simple eyes (ocelli); biting mouthparts; males have 2 pairs of long, narrow wings; all females (and males of some species) wingless; legs short, thick, with 3‐segmented tarsi; swollen basal tarsal segment of forelegs bears silk gland; hind femora enlarged; abdomen 10‐segmented, with 2‐segmented cerci at tip. Life cycle: Nymphs adultlike, without...

Whistlers

Whistlers   Reference library

The New Encyclopedia of Birds

Reference type:
Subject Reference
Subject:
Science and technology, Life Sciences
Length:
639 words
Illustration(s):
3

...Australasia and SE Asia Habitat All habitats from rainforest to arid scrub. Size Length 11–26cm (4–10in); weight: 12–80g (0.5–3oz). Plumage Gray or brown, but adult males of many species brightly colored. Voice Distinctive, melodious, whistling or bell-like songs; harsher contact calls. Nest Carefully woven cups of grasses, lichen, twigs, and bark chips, held together by spider's webs, usually placed in fork of a tree or shrub. Eggs 2–4, white to buff, usually with a ring of brown to gray blotches at the larger end. Incubation period 14–18 days; nestling...

Trust and Social Relations in African Politics

Trust and Social Relations in African Politics   Reference library

Dominic Burbidge

The Oxford Encyclopedia of African Politics

Reference type:
Subject Reference
Current Version:
2020
Subject:
Social sciences, Politics
Length:
10,431 words
Illustration(s):
3

...Index (Range: 0 to 1) Burundi 8.20 483 0.530 Malawi 7.93 777 0.334 Mali 7.80 1,047 0.558 Burkina Faso 7.23 1,304 0.535 Tanzania 7.23 1,380 0.332 Mauritius 6.23 13,487 – Namibia 6.13 6,520 0.187 Mozambique 6.10 882 0.512 Kenya 5.97 1,522 0.229 Zimbabwe 5.73 – 0.172 Uganda 5.70 1,165 0.367 Algeria 5.60 7,339 – Zambia 5.40 1,475 0.328 Sierra Leone 5.37 1,171 0.439 South Africa 5.30 9,860 0.057 Cape Verde 5.23 3,818 – Ghana 5.17 1,764 0.144 Benin 4.80 1,364 0.412 Lesotho 4.50 1,692 0.156 Liberia 4.50 564 0.485 Togo 4.50 906 0.284 Nigeria 4.00 2,294 0.310 Botswana...

Long-tailed Tits

Long-tailed Tits   Reference library

The New Encyclopedia of Birds

Reference type:
Subject Reference
Subject:
Science and technology, Life Sciences
Length:
1,001 words
Illustration(s):
3

...Tits Order: Passeriformes Family: Aegithalidae 7 species in 2 genera: bushtit ( Psaltriparus minimus ), Long-tailed tit ( Aegithalos caudatus ), Black-browed tit ( A. iouschistos ), Black-throated tit ( A. concinnus ), White-cheeked tit ( A. leucogenys ), White-necklaced tit ( A. fuliginosus ), White-throated tit ( A. niveogularis ). Distribution Europe to Asia; N and C America Habitat Mainly forest and woodland Size Length 9–14cm (3.5–5.5in); weight 5–9g (0.20.3oz). Plumage Chiefly black, gray, white, and brown, with pink in the...

Gnatcatchers

Gnatcatchers   Reference library

The New Encyclopedia of Birds

Reference type:
Subject Reference
Subject:
Science and technology, Life Sciences
Length:
921 words
Illustration(s):
2

...the Caribbean. Habitat In forest, woodland, and scrub, including quite dry areas. Size Length 9–12cm (3.7–4.8in); weight about 6–10g (0.25–0.4oz); slight difference between sexes in some species. Plumage Gray and black (gnatcatchers); brown with pale underparts (gnatwren). Voice Simple whistles and calls, chips, and rather nasal soft notes. Nest Substantial pile of dead leaves with deep cup, or neat saucer on branch. Eggs 2–6; pale ground (blue. olive, or stone) with a few darker dots and speckles. Diet Insects and other arthropods. Conservation status The...

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