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Project

1-Wire Weather Station

The weather station in this project is quite basic, measuring only temperature, pressure, and humidity, but it may be easily expanded to measure other weather components, such as wind speed and rainfall. The design is based on using a series of…

Project

3D Terrain Map

Terrain maps are physical models that give you an at-a-glance overview of landforms. Architects, builders, and engineers often use these types of maps to provide context to proposed building designs. In this project, you'll create a layered…

Project

Wind Lantern

In this project, you will build a small, vertical-axis wind turbine, or VAWT for short. VAWTs are not as efficient as their horizontal-axis cousins, but they are better suited to urban environments where wind can come from different…

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from article Medical waste

The uniform international biohazard symbol.

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from article Convection in the Earth

Pattern of magnetic stripes over the Reykjanes Ridge southwest of Iceland. (After J. R. Heirtzler, X. LePichon, and J. G. Baron, Magnetic anomalies over the Reykjanes Ridge, Deep Sea Res., 13:427, 1966)

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from article Convection in the Earth

Geographic setting of the Kurile Trench off the Kamchatka Peninsula, showing the deep ocean trench and the characteristic line of volcanoes in the vicinity of the subduction zone. The sections A′ and B′ illustrate the bathymetry normal to the trench…

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from article Convection in the Earth

Characteristic variation of heat flow and bathymetry. (a) Variation of surface heat flow as a function of age of the ocean floor in millions of years before present for the Pacific, South Atlantic, and Indian oceans. (b) Variation of sea-floor…

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from article Convection in the Earth

Global seismicity showing surface projections of all earthquakes which occurred during 1965–1975 with magnitudes in the range 4.5–5.5. Plate boundaries are located along the seams marked by high frequency of earthquake occurrence.

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from article Convection in the Earth

Map of global tectonic and volcanic activity over the past million years. (After The Physical World, National Geographic Society, Van der Grinten projection, 1975)

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from article Seawater

Vertical distribution of phosphate (PO43−) at three stations to show a range of characteristics found in major oceanic regions. North Atlantic is from a region in the central North Atlantic northeast of Bermuda and North Pacific is from the central…

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from article Seawater

Vertical distribution of total carbon dioxide concentrations at locations in the North Atlantic and North Pacific. Below depths of a few hundred meters, the distributions are generally characteristic of fairly large regions in the two oceans.

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from article Seawater

Layers in seawater in a section through the Atlantic Ocean from the Greenland Sea (right) to the Weddell Sea (left). The thick line represents depth. (a) Potential temperature; contour values are in °C (°F). (b) Salinity; contours are in parts per…

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from article Seawater

Layers in seawater in a section through the western Indian Ocean from India (right) to Antarctica (left). The thick line represents depth. (a) Potential temperature; contour values are in °C (°F). (b) Salinity; contours are in parts per thousand.

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from article Seawater

Layers in seawater in a section through the Pacific Ocean from the Aleutian Islands (right) to the Ross Sea (left). The thick line represents depth. (a) Potential temperature; contour values are in °C (°F). (b) Salinity; contours are in parts per…

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from article Huntington's disease

Huntington's disease is a hereditary disorder that affects approximately five to ten of every 100,000 persons. The average age at onset is between 35 and 40 years. Invariably fatal, the disease progresses gradually over time. (Copyright ©…

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from article Masking of sound

Three psychophysical tuning curves, showing the tonal masking effects for tonal signals of 300, 1000, or 3000 Hz. (After F. L. Wightman et al. Factors influencing frequency selectivity in normal and hearing-impaired listeners, in E. F. Evans and J.…

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from article Masking of sound

Width of the critical band in hertz as a function of signal frequency.

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from article Masking of sound

Relative amount of masking obtained in forward, simultaneous, and backward masking. (After W. A. Yost, Fundamentals of Hearing: An Introduction, 4th ed., Academic Press, New York, 2000)

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from article Masking of sound

Masking of a 1000-Hz pure-tone signal in forward masking when the masker is a two-tone complex consisting of a 1000-Hz masker and a second tone. (a) Threshold of signal for the two-tone masker relative to that obtained when only the 1000-Hz tone…

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from article Pharmacy

Pharmacy is the science dealing with the preparation and dispensing of medicinal or therapeutic drugs. (Credit: Sanchai Rat/Shutterstock)

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from article Ultrahigh-pressure metamorphism

Schematic cross-section contrasting the tectonic setting of generation and exhumation of (a) Alpine-type and (b) Pacific-type HP-UHP belts. (Modified after Maruyama et al., 1996)

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from article Ultrahigh-pressure metamorphism

P-T diagram showing (a) HP-UHP regimes and stability of coesite and diamond, (b) P-T-time paths for Dabie-Sulu eclogite and garnet peridotite, and (c) zoned zircon domains with sensitive high-resolution ion microprobe (SHRIMP) U/Pb ages for Sulu…

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from article Ultrahigh-pressure metamorphism

Photomicrographs of UHP index minerals. Inclusions of coesite in omphacite from (a) Dabie, and coesite pseudomorph in epidote from (b) Sulu, central-eastern China. Inclusions of (c) microdiamond in zircon, and (d) diamond + phengite in garnet, from…

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from article Barrier islands

Generalized profile across a barrier island complex showing various environments.

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from article Barrier islands

Sediment budget for barrier island complex. Solid lines are major interactions; broken lines are relatively minor intersections.

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from article Barrier islands

Maps showing major coastal environments and directions, and directions of coastal processes of (a) wave-dominated barrier islands and (b) mixed-energy barrier islands. Large arrows indicate wave direction, and small arrows indicate direction of…

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from article Hepatitis C virus

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from article Hepatitis C virus

Natural history of chronic hepatitis C. It is presumed that liver fibrosis progresses in a linear course from the time of acquisition of the infection to the development of cirrhosis. Stages of fibrosis are from the METAVIR (meta-analysis of…

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from article Hepatitis C virus

The genomic structure of hepatitis C virus (HCV) and potential targets for therapy. Through analysis of the genomic structure of HCV, additional therapies (for example, serine protease inhibitors, helicase inhibitors, and RNA polymerase inhibitors)…

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from article Stishovite

Comparison of the mean index of refraction and specific gravity of stishovite and other polymorphic modifications of silica.

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from article Melanterite

Fibrous crust of melanterite (a common mineral) in a sample from Kremnitz, Hungary. (Specimen from Department of Geology, Bryn Mawr College)

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from article Tidal bore

Tidal curve of a river with a tidal bore.

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from article Tidal bore

Tidal bore of the Petitcodiac River, Bay of Fundy, New Brunswick, Canada. Rise of water is about 4 ft (1. 2 m). (New Brunswick Travel Bureau)

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from article Earth

The famous "Blue Marble" picture of Earth taken by astronauts during the Apollo 17 mission on December 7, 1972, while en route to the Moon. (Credit: NASA)

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from article Earth

Principal layers of Earth. (USGS)

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from article Earth

Global histogram (distribution of elevations) and hypsographic curve (cumulative elevations) of Earth's surface. (NOAA)

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from article Earth

Seafloor spreading. (USGS)

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from article Earth

Plate collisions: (a) continent-ocean plate collision; (b) continent-continent plate collision; (c) ocean-ocean plate collision. (USGS)

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from article Earth

Structure of the atmosphere. The log scale applies only to the ionization curve. 1 km = 0.6 mi; °F = (°C × 1.8) + 32.

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from article Surgery

Medical personnel performing a surgical procedure in a modern operating room. (Credit: OJO Images Limited/Alamy Stock Photo)

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from article Surgery

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from article Surgery

Close-up view of a surgeon organizing the instruments required for an operation. (Credit: ER Productions Limited/Blend Images)

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from article Surgery

A medical operation involving a robot. Robotic surgery is being implemented to perform procedures that once required the presence of an expert surgeon. (Credit: Master Video/Shutterstock)

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from article Baltic Sea

Postglacial development of the Baltic: (a) Baltic Ice Sea, 12,000–8000 B.C.; (b) Yoldia Sea, 8000–7250 B.C.; (c) Ancylus Sea, 7250–2000 B.C.; (d) Littorina Sea, 2000–A.D. 500. (After K. Grasshoff, in S. P. Riley and G. Skirrow, eds., Chemical…

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from article Food allergy

Children (under the age of 18) who experience food allergies are more likely to experience other allergic conditions, including asthma (black), eczema/skin allergy (blue), and respiratory allergy (green). (Credit: National Center for Health…

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from article Food allergy

Allergic responses (immunological responses mediated by the IgE class of immunoglobulins) can be caused by certain foods. In a person with allergies, mast cells will be coated with IgE against one or a few antigens (allergens) that, upon entering…

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from article Food allergy

Peanuts are a common trigger of food allergies in both adults and children. (Credit: Christian Jung/Shutterstock)

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from article Sport-related concussion

Sport-related concussion is among the most frequent injuries experienced by athletes participating in contact and collision sports, including football. (Credit: skynesher/Getty Images)

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from article Sport-related concussion

Medical imaging and scanning techniques can identify the brain areas affected by a sport-related concussion. (Credit: Puwadol Jaturawutthichai/Shutterstock)

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from article Sport-related concussion