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Scientific Tools in changing our life

Searching for excellence can lead to change, both in your lab and in the tools we design to improve your procedures. Over 17 years ago, we introduced the UniFit (universal-fitting pipet tip) concept, which soon became the biotech research lab standard. Today, we are continuing the tradition by introducing the next generation of UniFit pipet tips in premium packaging at unbeatable-value prices.

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Astronomical Instruments:

The elegant rings and bands of an armillary sphere (below) symbolize the astronomy of the past. The armillary sphere takes its name from the Latin armilla, meaning a bracelet or metal ring. With the Earth located at the center, the rings trace out what an observer sees in the night sky without a telescope. The outer band, that supports the device, shows the observers horizon and the meridian. Inside these bands is a cagelike assembly of rings that rotate to display the durinal motion of the stars. The zodiac is represented by a broad band marked with the 12 signs.




Locating stars and measuring their positions precisely is no simple task. One of the earliest astronomical instruments is the quadrant, shown below, which measures a stars altitude above the horizon. A quadrant acquires its name by its ability to measure within a quarter circle. Using spherical trigonometry, the zenith distance could then be used to calculate a stars celestial longitude and latitude. Quadrants made of metal allowed finer intervals to be ruled for more precise measurements.




The astrolabe was a sophisticated time-telling instrument of late antiquity. It was an all-in-one tool for calculating the position of the Sun (thus, local time) and various stars. The typical astrolabe has a rotating cutaway disk, called the rete, that represents the heavens as they revolve around us. Labeled points represent stars, the solid band is the zodiac. A plate, or tympan, is fixed beneath the rete and is inscribed with altitude and azimuth coordinates for the particular latitude where the astrolabe is used. Since the astrolabe displays the coordinates of various bright stars, it can also be used to determine the time at night when the Sun is not visible. Astrolabes were of particular interest to the ancient Muslim culture since it provided the direction to Mecca for daily prayers.




The mechanized planetarium, one of the most popular scientific tools of the 1700's, displayed the motion of the planets around the Sun. The operation of the device's carefully crafted mechanisms inspired awe and wonder at the sense of the Universe's divinely imposed stable order. Astronomical knowledge was a mark of education and social status and the ownership of a planetaria gave material evidence of such status. The planetaria below was constructed for King George II.

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Constellations:
Drawn onto the celestial sphere are imaginary shapes called constellations, Latin for `group of stars'. Constellations organize the stars into more easily identifiable groups, thus easier to remember. The exact origin of the constellations is lost, but 48 had been established by ancient Greek times which are called the Ptolemaic constellations after Ptolemy's star catalog in the Almagest. Constellations are often drawn in the shapes of mythical heros and creatures tracing a pattern of stars on the celestial sphere, recorded on a star map.




The illustrators of star catalogs depicted the constellations without reference to the night sky, as a result their images do not resemble the actual patterns or brightnesses of the stars. For many of the constellations it is easy to see where they got their names. For example,




Aquila, the Eagle

Hercules, the Warrior

Scorpius, the Scorpion
Because both Asian and European astronomers lived in the norther hemisphere, constellations were missing around the South Celestial Pole until expeditions to the New World. Shown below, astronomer Amerigo Vespucci maps the Southern Cross (Crux) in 1589.

In ancient China, astronomers held high social position with close connections to the imperial court. Many of the same astronomical instruments used in Europe were also used by Chinese astronomers as shown in the pictograph below. Astronomical knowledge passed from India to China (in return magnetized compass needles were sent to Europe so that Western navigators could sail the open seas).

Chinese astronomers emphasized the close relationship between heaven and Earth. They believed that events in heaven reflected those on the Earth. For example, new occurrences, such as a novae, signaled important changes on Earth. Chinese star charts, shown below, divided the stars into `lunar mansions', similar to constellations. The Milky Way was referred to as the `Yellow River', linking them both to seasonal rainfall.

In all, there are 88 constellation names cataloged by Hipparchus in 100 B.C. To find out more about your favorite constellation, goto Constellation of the Month.
The development of larger telescopes, like Herschel's first telescope shown below, allowed the discovery of many stars invisible to the naked eye.

Stars now filled the areas of the sky that previously seemed empty. By the start of the 19th century, pictorial celestial atlases became impractical, even though astronomers continued to make up new constellations.

Star charts evolved into those that featured the stars as austere points sometimes with boundary lines dividing the sky into regions defined by their old constellation names. Star charts for the general public continued to feature the faint outlines of the earlier star charts, but later took on more geometric shapes.

One of the jobs for astronomers in the 17th and 18th centuries was to educate the public on unusual astronomical events, such as comets and eclipses. Typically this was done using printed information sheets called broadsides. The broadside below explains the science behind a total eclipse of the Sun.

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Star Names:
Hipparchus also developed a simply method of identifying the stars in the sky by using a letter from the Greek alphabet combined with the constellation name.

So, for example, the brightest star in the constellation Orion is Alpha Orion, the second brightest star is Beta Orion, and so on. As more and more stars were cataloged, this system was insufficient. By the 1600's, a system was devised to assign letters to each star in a constellation, roughly by descending brightness, beginning first with the Greek alphabet and then, when those letters were exhausted, continuing with the Roman alphabet. When the letters run out, we use a number 33 Orion, 101 Orion, etc. Some of the very brightest stars have their own names due to their importance to early navigators. For example, Alpha Canis Major is Sirius, the Dog Star.

About 6000 stars are visible with the naked eye on a dark, moonless night. However, there are over 10¹³ stars in the whole Milky Way galaxy were the solar system resides. Thus, we only see a very small fraction of the closest and brightest stars with our eyes.

Since the Earth's axis is tilted 23 1/2 degrees from the plane of our orbit around the Sun, The apparent motion of the Sun through the sky during the year is a circle that is inclined 23 1/2 degrees from the celestial equator. This circle is called the ecliptic and passes through 12 of the 88 constellations that we call the zodiac.

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Observatories:
The first need for astronomical observatories was time and calendar keeping. Ancient civilizations referenced astronomical events to mark the reigns of various kings. Civil calendars were derived from the lunar calendar sometime in the 3rd millennium B.C.
The Egyptians constructed the pyramids for tracking Sirius, the Dog Star, in the sky. When Sirius became visible above the horizon, then it was known that the Nile was going to flood, an important time to plant crops.

In Mesopotamia ziggurats were constructed of mud brick to observe the position of the Moon and planets, again to mark the passage of time.

However, no astronomical instruments appears to be used other than the buildings themselves. The first extensive system of astronomical tools was Stonehenge.
The job of early observatories was to map the sky, so the earliest astronomical instrument was the quadrant or sextant. Using these instruments, Hipparchus at Rhodes (150 B.C.) produced the first star catalog, measured precession and developed the magnitude system of stellar brightness. Islamic observatories at Damascus and Baghdad tested our first solar system models.
The first modern observatory was constructed in Denmark by Tycho Brahe in 1576.

With the invention of optics, observatories added telescopes to their collection of instruments. Telescopes serve to 1) magnify nearby planets, to study surface features, 2) collect light to detect faint stars and 3) transfer light to recording instruments, such as a photographic plate to take a picture, or to a spectrograph to take a spectrum.
Due to effects of the atmosphere, telescopes are typically located on mountain tops because

1. they are dry sites (few clouds),
2. high above the thick currents of air so the images are clear and steady and
3. to allow more UV (ultraviolet) and IR (infrared) photons which are blocked by lower atmosphere.

Our national telescopes are located at Kitt Peak in Arizona for the northern hemisphere and Chile for the southern hemisphere (you can't see southern constellations from the northern hemisphere, nor northern ones from the southern hemisphere).

Optical astronomy has dominated for centuries until the development of space telescopes. To observe at high energies (gamma and x-rays) or in the far-IR and microwave regions of the spectrum, the telescope must be located above the Earth's atmosphere.
For example, this orbiting IR telescope, launched in 1994:

The AXAF/Chandra X-ray telescope, now in orbit:

and a shuttle launched gamma-ray telescope, now de-orbited:

Space observatories have an advantage even in regions of the spectrum that we can see from the ground (i.e. the visible region of the spectrum). Being above the atmosphere means being able to resolve stars and galaxies to much finer detail than ever seen before, and the flagship of space telescopes is the Hubble Space Telescope shown below.

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Optical Telescopes:
The simplest telescope is two lens separated by a tube. Since the objective lens (the front lens) refracts the incoming light, this kind of instrument is called a refracting telescope.


Note that the objective lens brings the incoming light to a focus, and then the eyepiece magnifies that focal region for the eye. So it is a combination of a lens and microscope. Galileo used this type of telescope to discover the phases of Venus and the moons of Jupiter. The type of telescope you would buy today looks like the following:

The objective lens is surrounded by a series of baffles to block stray light. A small mirror is placed near the complicated eyepiece to turn the light upward from the telescope for a more comfortable viewing position.
The limitation on refracting telescopes is that glass is only a semi-solid and will deform with time. So very large lens will not stay round, plus they are extremely heavy. For these reasons, the largest refracting telescope is limited to 40 inches in diameter.
In order to build larger telescopes to gather more light to see fainter stars, most optical telescopes employ a reflecting telescope design invented by Newton. In this case, a large concave mirror reflects the incoming light into a focal point. Four different reflecting designs are used, depending on where the focal point is placed.

The various focus designs relate to a telescopes use. For example, a prime focus system is poor on small telescopes because your head gets in the way. So most commercial telescopes have a Newtonian design. However, for large telescopes (greater than 2 meters in mirror size), the prime focus system is use since it has a minimal number of optical elements in the way to distort light.

If a heavy instrument is used on the telescope, for example a CCD camera, then the instrument must be placed at the cassegrain focus. If an extremely heavy instrument is used, then the stellar light is reflected down the axis of the telescope into separate machine rooms below the telescope. This is called a Coude design.

The larger the telescope, the more light gathering power, the fainter the stars you can measure. But there is a limit to the size of a primary mirror given by the ability for glass to support it own weight (it flows and cracks under stress). For a refracting telescope, the limit for the diameter of the objective lens is about 48 inches. For a reflecting telescope, the limit of the size of a single primary mirror is about 8 meters. The Keck twins are the largest telescopes in the world, using a new technology of a segmented primary to make a 10 meter mirror.

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Radio Telescopes:
Radio telescopes gather radio waves from stellar objects. Since radio waves are reflected by metal, they are typical made of solid aluminum or steel mesh.

The difference wavelength of the light in the radio region (centimeters and meters) means a different technology to analysis them. In the case of radio astronomy, a sophisticated radio receiver is used such that the power of the telescope is determined by the area of the antenna and the sensitivity of the electronics.
Radio telescopes can also use the phenomenon of interference to obtain high resolution. Many antennas, working together, measure the interference patterns from distant sources and combine them to produce highly detailed maps in the radio region of the spectrum. An example is the Very Large Array shown below.

Since radio telescopes are made of metal, and not glass, they can be made very large. An extreme example of this is the Arecibo Telescope in Puerto Rico, strung between two mountain ranges in Puerto Rico.

Scientific Theories, Discoveries, News and Facts

Science and research are two words or concepts that so closely related that they are almost interchangeable with one another. Science can best be described as systematic gathering of knowledge of the world and its occurrences and phenomena through observation and experimentation. Research can be defined as a systematic approach to gather information and [...]

Scientific Theories

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In the scientific world, experiments and various types of studies are used to compile a collection of data and results. According to the scientific method, the data obtained from experiments used to explain a hypothesis must able to be repeated in order to conclude any validity to the final claims or results. Furthermore, [...]

Science Discoveries

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The study of science allows for amazing discoveries for occur everyday. The natural world is constantly changing, and therefore, new knowledge about our immediate environment is there to be gained. It is through forward progress in the fields of science and technology that scientist can explore the realms of possibility to gain new [...]

Science News

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Science is will always be constant flux because it deals the nature of knowledge. Science encompasses such a vast amount of knowledge that the human mind can not possibly fathom. Furthermore, because science essentially deals with the changes of the natural, it is impossible to put any kind of quantifiable value to the [...]

Scientific Facts

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Science facts can refer to findings and conclusions carried out by experiments to help validate a particular hypothesis. Because scientific findings are corrugated by extensive research, experiments, data, and a methodical approach and logic, it may be argued that those things that may be considered as scientific facts are the most true in the [...]

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Engineer the tools of scientific discovery

In the century ahead, engineers will continue to be partners with scientists in the great quest for understanding many unanswered questions of nature.

In the popular mind, scientists and engineers have distinct job descriptions. Scientists explore, experiment, and discover; engineers create, design, and build.

But in truth, the distinction is blurry, and engineers participate in the scientific process of discovery in many ways. Grand experiments and missions of exploration always need engineering expertise to design the tools, instruments, and systems that make it possible to acquire new knowledge about the physical and biological worlds.
In the century ahead, engineers will continue to be partners with scientists in the great quest for understanding many unanswered questions of nature.

How will engineering impact biological research?

Biologists are always seeking, for instance, better tools for imaging the body and the brain. Many mysteries also remain in the catalog of human genes involving exactly how genes work in processes of activation and inhibition. Scientists still have much to learn about the relationship of genes and disease, as well as the possible role of large sections of our DNA that seem to be junk with no function, leftover from evolution.
To explore such realms, biologists will depend on engineering help — perhaps in the form of new kinds of microscopes, or new biochemical methods of probing the body’s cellular and molecular machinations. New mathematical and computing methods, incorporated into the emerging discipline of “systems biology,” may show the way to better treatments of disease and better understanding of healthy life. Perhaps even more intriguing, the bioengineering discipline known as “synthetic biology” may enable the design of entirely novel biological chemicals and systems that could prove useful in applications ranging from fuels to medicines to environmental cleanup and more.
Turning to the mysteries of our own minds, new methods for studying the brain should assist the study of memory, learning, emotions, and thought. In the process, mental disorders may be conquered and learning and thinking skills enhanced. Ultimately, such advances may lead to a credible answer to the deepest of human mysteries, the question of the origin and nature of consciousness itself.

How will engineering help

Priority environment and health risks

Priority risks: The human toll

• Download full policy brief: Priority risks and future trends

Environmental factors are a root cause of a significant disease burden, particularly in developing countries. An estimated 25% of death and disease globally, and nearly 35% in regions such as sub-Saharan Africa, is linked to environmental hazards. Some key areas of risk include the following:

• Unsafe water, poor sanitation and hygiene kill an estimated 1.7 million people annually, particularly as a result of diarrhoeal disease.
• Indoor smoke from solid fuels kills an estimated 1.6 million people annually due to respiratory diseases.
• Malaria kills over 1.2 million people annually, mostly African children under the age of five. Poorly designed irrigation and water systems, inadequate housing, poor waste disposal and water storage, deforestation and loss of biodiversity, all may be contributing factors to the most common vector-borne diseases including malaria, dengue and leishmaniasis.
• Urban air pollution generated by vehicles, industries and energy production kills approximately 800 000 people annually.
• Unintentional acute poisonings kill 355 000 people globally each year. In developing countries, where two-thirds of these deaths occur, such poisonings are associated strongly with excessive exposure to, and inappropriate use of, toxic chemicals and pesticides present in occupational and/or domestic environments.
• Climate change impacts including more extreme weather events, changed patterns of disease and effects on agricultural production, are estimated to cause over 150 000 deaths annually.

Living Things

Scientific Instruments

Scientific Instruments

Have you ever been in the middle of a class lecture, medical examination or episode of Star Trek only to realise suddenly that you have no clue what all those gizmos, gadgets and other scientific instruments actually do? If so, your problems are solved. This list defines 418 scientific instruments and technical tools used for viewing, displaying, recording and measuring just about anything you can imagine (and some things you probably can't). Most of these words end in "meter" (instruments for measuring), "scope" (instruments for viewing) or "graph" (instruments for displaying and recording). Word Definition absorptiometer instrument for measuring solubility of gases in liquids accelerometer instrument for measuring acceleration or vibrations acetimeter instrument for measuring strength of vinegar acidimeter instrument for measuring concentration of acids actinograph instrument used to calculate time of photographic exposure actinometer instrument for measuring incident radiation aerometer instrument for measuring weight or density of gas aethrioscope instrument for measuring temperature variations due to sky conditions alcoholometer instrument for measuring proportion of alcohol in solutions alcovinometer instrument to measure strength of wine algometer instrument for measuring sensitivity to pain alkalimeter instrument for measuring strength of alkalines altimeter instrument for measuring altitude ammeter instrument for measuring electrical current anemograph instrument for measuring pressure and velocity of wind anemometer instrument for measuring wind velocity areometer instrument used for measuring specific gravity arthroscope instrument for examining interior of a joint atmometer instrument for measuring evaporating capacity of air audiometer instrument for measuring acuity of hearing auriscope instrument for examining the ear auxanometer instrument for measuring growth of plants auxometer instrument for measuring magnifying power ballistocardiograph instrument for detecting body movements caused by heartbeat barograph instrument for recording air pressure barometer instrument for measuring air pressure baroscope weather-glass bathymeter instrument for recording contours of deep oceans bathythermograph instrument for recording water temperature as compared to depth bolometer instrument for measuring radiant energy or infrared light bronchoscope instrument for examining the windpipe calorimeter instrument for measuring absorbed or evolved heat cardiograph instrument for recording movements of the heart cathetometer instrument for measuring short vertical distances ceilometer instrument for measuring height of cloud ceiling above earth ceraunograph instrument for recording thunder and lightning chlorometer instrument for measuring amount of chlorine in a solution chromatograph instrument for performing chromatographic separations chromatoptometer instrument measuring eyes' sensitivity to colour chronograph instrument for recording the moment of an event chronometer instrument for measuring time chronoscope instrument for measuring very short time intervals clinometer instrument used to measure slopes and elevations coercimeter instrument for measuring coercive force colonoscope instrument for viewing the colon colorimeter instrument for measuring and determining color colposcope instrument for viewing the neck of the uterus coronagraph instrument for viewing the corona of the sun coulombmeter instrument for measuring electric charge coulometer instrument measuring amount of substance released in electrolysis craniometer instrument for measuring the skull cratometer instrument for measuring power of magnification crescograph instrument for measuring the growth of plants cryometer instrument for measuring low temperatures cryoscope instrument for determining freezing points of substances cyanometer instrument for measuring blueness of the sky or ocean cyclograph instrument for describing arcs of circles without compasses cyclometer instrument for measuring revolutions of a wheel cymograph instrument for tracing the outline of mouldings cymometer instrument for measuring frequency of electrical waves cystoscope instrument for examining the bladder cytometer instrument for counting cells decelerometer instrument for measuring deceleration declinometer instrument for measuring magnetic declination dendrometer instrument for measuring trees densimeter instrument for measuring closeness of grain of a substance densitometer instrument for measuring optical or photographic density diagometer instrument for measuring electrical conductivity diagraph instrument for enlarging or projecting drawings diaphanometer instrument for measuring the transparency of air dichroscope instrument for examining crystals for dichroism diffractometer instrument for determining structure of crystal through light diffraction dilatometer instrument for measuring expansion dioptometer instrument for measuring focus or refraction of the eyes dipleidoscope instrument for measuring moment when an object passes a meridian diplograph instrument for writing two lines of text at once dosimeter instrument for measuring dose of radiation dromometer instrument for measuring speed drosometer instrument for measuring dew durometer instrument for measuring hardness of substances dynamograph instrument for recording mechanical forces dynamometer instrument for measuring mechanical force ebullioscope instrument for measuring boiling point of liquids effusiometer instrument for comparing molecular weights of gases eidograph instrument for copying drawings elatrometer instrument for measuring gaseous pressure electrocardiograph instrument for recording unusual electrical fluctuations of the heart electrodynamometer instrument for measuring electrical current electroencephalograph instrument for measuring the brain's electrical impulses electrograph instrument for recording electrical potential electrometer instrument for measuring electrical potential electromyograph instrument for diagnosing neuromuscular disorders electroretinograph instrument for measuring electrical activity in the retina electroscope instrument for detecting electrical charges in the body ellipsograph instrument for describing ellipses encephalograph instrument for recording brain images endoscope instrument for visualizing interior of a hollow organ endosmometer instrument for measuring osmosis into a solution epidiascope instrument for projecting images of objects episcope instrument for projecting images of opaque objects ergograph instrument for measuring and recording muscular work ergometer instrument for measuring work performed eriometer instrument for measuring very small diameters eudiometer instrument for measuring air purity evaporimeter instrument for measuring rate of evaporation extensometer instrument for measuring deformation in object due to forces applied fathometer instrument for measuring underwater depth using sound fiberscope instrument using fiberoptics to examine inaccessible areas floriscope instrument for inspecting flowers flowmeter instrument for measuring properties of flowing liquids fluorimeter instrument for measuring fluorescence fluoroscope instrument using x-rays to examine internal structure of opaque object focimeter instrument for measuring focal length of a lens galactometer instrument for measuring specific gravity of milk galvanometer instrument for measuring electrical current galvanoscope instrument for detecting presence and direction of electric current gasometer instrument for holding and measuring gases gastroscope instrument for examining interior of the stomach geothermometer instrument for measuring subterranean temperatures goniometer instrument for measuring angles between faces gradiometer instrument for measuring gradient of a physical quantity gravimeter instrument for measuring variations in gravitational fields gyrograph instrument for counting a wheel's revolutions haptometer instrument measuring sensitivity to touch harmonograph instrument drawing curves representing vibrations harmonometer instrument measuring harmonic relations of sounds helicograph instrument for drawing spirals on a plane heliograph instrument for measuring intensity of sunlight heliometer instrument for measuring apparent diameter of the sun helioscope instrument for observing sun without injury to the eyes hemacytometer instrument for counting blood cells hippometer instrument to measure height of horses hodoscope instrument for tracing paths of ionizing particles hydrometer instrument for measuring specific gravity of liquids hydroscope instrument for viewing under water hydrotimeter instrument for measuring water hardness hyetograph instrument for recording rainfall hyetometer instrument for measuring rainfall hyetometrograph instrument for recording rainfall hygrograph instrument for recording variations in atmospheric humidity hygrometer instrument for measuring air moisture hygroscope instrument for displaying changes in air humidity hypsometer instrument for measuring height of trees through triangulation iconometer instrument for finding size of object by measuring its image idiometer instrument for measuring motion of observer in relation to transit of the heavens inclinometer instrument for measuring inclination to the horizontal of an axis interferometer instrument for analysing spectra of light iriscope instrument for exhibiting the prismatic colours katathermometer instrument for measuring the cooling power of air katharometer instrument measuring changes in composition of gases keratometer instrument for measuring curvature of the cornea keraunograph instrument for recording distant thunderstorms kinetoscope instrument for producing curves by combination of circular movements konimeter instrument measuring amount of dust in air koniscope instrument for measuring dust in air kymograph instrument for recording fluid pressure labidometer instrument for measuring size of the head of a fetus lactometer instrument for testing relative density of milk lactoscope instrument for measuring purity or richness of milk lanameter instrument for measuring quality of wool laparoscope instrument for viewing interior of peritoneal cavity laryngoscope instrument for examining interior of the larynx leptometer instrument for measuring oil viscosity loxodograph device used to record ship's travels lucimeter instrument for measuring light intensity luxmeter instrument for measuring illumination lysimeter instrument for measuring percolation of water through soil magnetograph instrument for recording measurements of magnetic fields magnetometer instrument for measuring intensity of magnetic fields manometer instrument for measuring pressure of a liquid or gas marigraph instrument for recording tide levels mecometer instrument for measuring length megameter instrument for determining longitude by observing stars megascope instrument for projecting an enlarged image mekometer range-finder meldometer instrument for measuring melting points of substances meteorograph instrument recording a variety of meteorological observations methanometer instrument for detecting presence of methane microbarograph instrument for recording minute changes in atmospheric pressure microcalorimeter instrument for measuring tiny quantities of heat micrograph instrument used to write on a very small scale micrometer instrument for measuring very small distances micronometer instrument for measuring short periods of time microscope instrument for magnifying small objects microseismograph instrument for recording small or distant earthquakes microseismometer instrument for measuring small or distant earthquakes mileometer instrument for recording distance travelled in miles milliammeter instrument for recording very small electrical currents myograph instrument for recording muscular contractions myringoscope instrument for viewing the eardrum nephelometer instrument for measuring cloudiness nephograph instrument for photographing clouds nephoscope instrument for observing direction and velocity of clouds nitrometer instrument for measuring nitrogen and its compounds odograph odometer; instrument for measuring distance travelled odometer instrument for measuring distance travelled odontograph instrument for obtaining curves for gear-teeth oenometer instrument for measuring alcoholic strength of wine ohmmeter instrument for measuring electrical resistance oleometer instrument for measuring amount of oil in a substance olfactometer instrument measuring intensity of odour of a substance ombrometer rain-gauge oncometer instrument measuring change in size of internal organs oncosimeter instrument measuring variations in density of molten metal ondograph instrument measuring change in wave formations of electricity oometer instrument for measuring eggs opacimeter instrument for measuring opacity opeidoscope instrument for illustrating sound by means of light ophthalmometer instrument for measuring the eye ophthalmoscope instrument for viewing the interior of the eye opisometer instrument for measuring curved lines opsiometer instrument for testing vision optometer instrument for testing vision orchidometer instrument for measuring the size of the testicles oscillograph instrument for recording alternating current wave forms oscillometer instrument for measuring ship's rollings oscilloscope instrument for detecting electrical fluctuations osmometer instrument for measuring osmotic pressure otoscope instrument for examining the ear pachymeter instrument for measuring small thicknesses pallograph instrument measuring ship's vibration pantochronometer combined sundial and compass pantograph instrument for copying drawing to a different scale passimeter instrument for issuing automatic tickets pedometer instrument for measuring distance travelled on foot peirameter instrument measuring resistance of road surfaces to wheel movement pelvimeter instrument for measuring the pelvis penetrometer instrument for measuring firmness or consistency of substances permeameter instrument for measuring permeability phacometer instrument for measuring lenses phaometer old instrument for measuring light intensity pharmacometer instrument for measuring drugs pharyngoscope instrument for inspecting the pharynx phonautograph instrument for recording sound vibrations phonendoscope device which amplifies small sounds phonometer instrument for measuring sound levels phorometer instrument used to correct abnormalities in eye muscles photometer instrument for measuring light intensity photopolarimeter instrument for measuring intensity and polarization of reflected light phototachometer instrument for measuring the speed of light phototelegraph instrument for transmitting drawings telegraphically phthongometer instrument measuring intensity of vowel sounds piezometer instrument for measuring pressure or compressibility pitchometer instrument for measuring angles of ship's propeller blades planigraph instrument for copying drawings at a different scale planimeter instrument for measuring area of plane figures platometer instrument for measuring area; planimeter plegometer instrument for measuring the strength of a blow plemyrameter instrument for measuring variations in water level plethysmograph instrument for measuring change in body part size due to blood flow pluviograph self-registering rain gauge pluviometer rain-meter pneometer instrument that measures respiration pneumatometer instrument for measuring quantity of air breathed pneumograph instrument for measuring and recording respiration polarimeter instrument for measuring polarised light polariscope instrument for detecting polarized light polygraph instrument for measuring small changes in pulse and respiration porometer instrument for measuring degree of porosity poroscope instrument for investigating porosity potentiometer instrument for measuring electromotive forces potometer instrument measuring rate at which plants absorb water prisoptometer instrument for measuring degree of astigmatism proctoscope instrument for examining the rectum psophometer instrument measuring audible interference of electrical current psychograph instrument that supposedly records spirit messages psychrometer instrument for measuring air moisture or temperature psychrometer instrument for measuring dryness of the atmosphere pulsimeter instrument for measuring the pulse pycnometer instrument for measuring specific gravity or density pyknometer instrument for measuring specific gravities pyranometer instrument measuring solar radiation from the sky's whole hemisphere pyrgeometer instrument for measuring radiation from earth pyrheliometer instrument for measuring heating effect of sun pyrometer instrument for measuring very high temperatures pyroscope instrument for measuring intensity of radiant heat qualimeter apparatus for measuring penetrating power of X-ray beams quantimeter apparatus for measuring quantity of X-rays quantometer instrument for measuring proportions of elements in metallic samples rachiometer instrument for measuring the spine radarscope instrument for detecting radar signals radiogoniometer instrument for finding direction through radio signals radiometeorograph instrument for measuring atmospheric conditions at high altitude radiometer instrument measuring radiation energy radioscope instrument for viewing objects using X-rays ratemeter instrument for measuring counting rate of electronic counters recipiangle old instrument with two arms used for measuring angles reflectometer instrument for measuring reflectance of radiant energy refractometer instrument measuring refraction of light respirometer instrument for measuring and studying respiration retinoscope instrument for measuring and viewing the retina rheometer instrument that measures current rhinoscope instrument for examining the nose rhythmometer instrument for measuring speed of rhythms riometer instrument for measuring absorbed cosmic radio waves rotameter old instrument for measuring length of curved lines rotameter instrument consisting of glass tube with free float for measuring liquid flow saccharimeter instrument for measuring amount of sugar in a solution salinometer instrument for measuring amount of salt in a solution scintillometer instrument measuring scintillation of star scintilloscope instrument for measuring gamma rays emitted by a radioactive body sclerometer instrument measuring hardness scoliometer instrument measuring curvature scotograph instrument for writing without seeing scotoscope instrument for detecting objects in darkness seismograph instrument for recording earthquakes seismometer instrument for measuring earthquake intensity seismoscope instrument for detecting earthquakes selenoscope instrument for viewing the moon sensitometer instrument for measuring sensitivity of photographic material sepometer instrument for measuring septic matter in the air serimeter instrument for testing quality of silk shuftiscope instrument used to explore interior of dysentery case siccimeter instrument for measuring liquid evaporation sideroscope instrument using magnets to detect presence of iron sigmoidoscope instrument for examining the interior of the rectum and sigmoid colon sillometer instrument measuring speed of ship skiascope instrument for measuring eye's refraction from movement of shadows snooperscope instrument for viewing infrared radiation solarimeter instrument for measuring solar radiation sonograph instrument for recording and analysing sound spectrofluorimeter instrument for measuring and recording fluorescence spectra spectrograph instrument for viewing a spectrum spectroheliograph instrument for taking pictures of the sun spectroheliokinematograph camera for taking pictures of the sun spectrohelioscope instrument for viewing solar disc in light of a single wavelength spectrometer instrument measuring wavelengths of light of a spectrum spectrophotometer instrument for measuring speed of different parts of light spectrum spectroscope instrument for forming spectra by dispersing rays of light speedometer instrument for measuring velocity spherometer instrument measuring curvature sphygmograph instrument for recording pulse sphygmomanometer instrument for measuring arterial blood pressure sphygmometer instrument for measuring arterial blood pressure sphygmoscope instrument for making arterial pulsations visible spinthariscope instrument for visually detecting alpha particles spirograph instrument recording movements of breathing spirometer instrument measuring lung capacity stactometer pipette with hollow bulb for counting drops stadiometer instrument for measuring the length of a curved line stagmometer instrument for measuring number of drops in volume of liquid stalagmometer instrument for measuring surface tension by drops statoscope instrument for measuring small changes in atmospheric pressure stauroscope instrument for studying structure of crystals with polarised light stenometer instrument for measuring distances stereometer instrument for measuring specific gravity stereoscope instrument for viewing special three-dimensional photographs stethometer instrument measuring chest expansion during breathing stethoscope instrument for detecting sounds produced by the body strabismometer instrument measuring degree of squinting strabometer instrument for measuring strabismus in the eyes stroboscope instrument for studying motion using flashes of light stylometer instrument for measuring columns swingometer instrument for measuring swing in votes during an election sympiesometer instrument for measuring pressure of a current synchroscope instrument for detecting whether two moving parts are synchronized tacheometer instrument for rapidly measuring survey points on a map tachistoscope instrument for rapidly showing images on a screen to test perception tachograph instrument for recording speed of rotation tachometer instrument for measuring speed of rotation taseometer instrument for measuring stress in a structure tasimeter instrument for measuring changes in pressure taximeter instrument for measuring fee for hired vehicle telemeter instrument for measuring strain or distance from observer telescope instrument for viewing objects at great distances telespectroscope instrument for analysing radiation omitted by distant bodies telestereoscope instrument for viewing distant objects stereoscopically tellurometer instrument using microwaves to measure distance tenderometer instrument for measuring tenderness of fruits and vegetables tensimeter instrument for measuring vapour pressure tensiometer instrument for measuring tension thalassometer instrument for measuring tides thermograph instrument for recording changes in temperature thermometer instrument for measuring temperature thermometrograph instrument for recording changes in temperature thermoscope instrument indicating change in temperature thoracoscope instrument for viewing the thorax and chest wall tiltmeter instrument for measuring tilting of earth's surface tocodynamometer instrument for measuring uterine contractions during childbirth tomograph instrument for viewing section of an object using X-rays tonometer instrument measuring pitch of musical tones topophone instrument to determine direction and distance of a fog-horn torsiograph instrument for recording torsional vibrations on an object transmissometer instrument for measuring transmission of light through a fluid trechometer instrument for determining distance travelled; odometer tremograph instrument for recording involuntary muscular motion tribometer instrument measuring friction trigonometer instrument for solving triangles trocheameter instrument counting wheel's revolutions tromometer instrument for measuring slight earthquake shocks tropometer instrument measuring rotation turbidimeter instrument for measuring turbidity of liquids turgometer instrument for measuring turgidity typhlograph instrument to help the blind write clearly udometer instrument for measuring rainfall ultramicroscope instrument for viewing extremely small objects urethroscope instrument for viewing the interior of the urethra urinometer instrument for measuring specific gravity of urine vaporimeter instrument for measuring vapour pressure variometer instrument for measuring magnetic declination velocimeter instrument for measuring velocity velometer instrument for measuring speed of air viameter instrument for measuring revolutions of a wheel vibrograph instrument for recording vibrations vibrometer instrument for measuring vibrations viscometer instrument for measuring viscosity visometer instrument for measuring focal length of the eye voltameter instrument for measuring electrical current indirectly voltmeter instrument for measuring electrical potential volumenometer instrument for measuring volume of a solid volumeter instrument for measuring volume of a liquid or gas wattmeter instrument for measuring electrical power wavemeter instrument for measuring wavelengths weatherometer instrument for measuring weather-resisting properties of paint xanthometer instrument for measuring colour of sea or lake water xylometer instrument measuring specific gravity of wood zymometer instrument for measuring fermentation zymosimeter instrument for measuring fermentation

Web-accessible directories for policy relevant questions

Web-accessible directories for policy relevant questions

Policymakers and stakeholders often seek answers to practical questions, including the following.

• How are environment and health linked?
• How many people does this hazard or risk affect?
• What kinds of "good practice" strategies have been used successfully elsewhere?
• What does this problem cost in economic terms; and what would alternative policies cost, or save in money and lives?
• Where can I obtain guidance on taking action and training for professionals who want to learn more?
• What resources exist for advocacy and participatory/community-based action?
• What kind of data is there regarding trends and indicators in this area?
• What international laws, conventions or strategies govern or guide action?

Links just below, and in the right-hand navigation column, take you to policy briefs and directories of web-accessible resources aimed at responding to such questions, by priority risk area. Maps portraying estimated disease burden or environmental disease burden, and its global distribution, also are provided by area of priority risk. These maps are based on World Health Organization burden of disease estimates, as reported in the World Health Report, and noted in the references of each priority risk section.
Links to programmes and portals sponsored by the World Health Organization, United Nations Environment Programme, and other United Nations agencies or affiliates, also are provided by priority risk area, as are selected links to other organizations, e.g. development agencies, academic/research and government/civil society institutions (see selection criteria).
In certain categories specific "problems" of topical relevance to developing countries have been identified for special focus, e.g. malaria in the category of vector-borne disease; agro-chemicals in the category of toxics.

Links to PRIORITY RISKS

• Vector-borne disease
• The urban environment
• Indoor air pollution and household energy
• Water, health and ecosystems
• Climate change
• Toxic substances

Priority environment and health risks

• View enlarged map
  pdf, 263kb

Priority risks: The human toll

• Download full policy brief: Priority risks and future trends

Environmental factors are a root cause of a significant disease burden, particularly in developing countries. An estimated 25% of death and disease globally, and nearly 35% in regions such as sub-Saharan Africa, is linked to environmental hazards. Some key areas of risk include the following:

• Unsafe water, poor sanitation and hygiene kill an estimated 1.7 million people annually, particularly as a result of diarrhoeal disease.
• Indoor smoke from solid fuels kills an estimated 1.6 million people annually due to respiratory diseases.
• Malaria kills over 1.2 million people annually, mostly African children under the age of five. Poorly designed irrigation and water systems, inadequate housing, poor waste disposal and water storage, deforestation and loss of biodiversity, all may be contributing factors to the most common vector-borne diseases including malaria, dengue and leishmaniasis.
• Urban air pollution generated by vehicles, industries and energy production kills approximately 800 000 people annually.
• Unintentional acute poisonings kill 355 000 people globally each year. In developing countries, where two-thirds of these deaths occur, such poisonings are associated strongly with excessive exposure to, and inappropriate use of, toxic chemicals and pesticides present in occupational and/or domestic environments.
• Climate change impacts including more extreme weather events, changed patterns of disease and effects on agricultural production, are estimated to cause over 150 000 deaths annually.

Scientific assessment tools

WHO; Rob Barnes

Even in a world of rapid information access, synthesizing vital scientific knowledge and evidence about environmental health problems, and potential solutions, into readily understandable concepts and statistics remains a formidable challenge.
However, a range of scientific tools exist to facilitate such synthesis. Those include tools for quantifying population health impacts (e.g. burden of disease assessment), which measure the health impacts of environmental hazards in very simple terms such as mortality. Another useful burden of disease measure, disability-adjusted life years (DALYs), combines the burden due to death and disability in a single index.
Geographic Information Systems (GIS) may, among other things, describe ecological features; patterns of ecological degradation/rehabilitation; identify areas of high risk; and provide information useful in monitoring trends. Environment and health indicators provide basic data to identify priority issues, and to track progress to the goal; Environment and health standards, guidelines and certain multilateral agreements/conventions set baselines or thresholds for permissible pollution or pollution exposure levels, and define goals to be achieved. Links to these resources are provided below.

• Health indicators/trends
  Description of trends and key health indicators, e.g. mortality, morbidity and health expenditure, as summarized in The World Health Report of the World Health Organization and its statistical annexes (available in PDF and excel formats).
• Environmental trends
  Background information on Global Environment Outlook Assessments
• Environmental data and indicators
  GEO data portal of the United Nations Environment Programme; more than 450 different variables; national, regional and global statistics/geospatial data sets;on range of themes including, freshwater, population, forests, emissions, climate, etc.
• Quantifying environmental health impacts
  Resources and methods for quantifying 'burden of disease' from key environmental risks at national and local level.
• Environmental mapping systems
  Policy brief and directory of resources.
• Children environmental health indicators
  Also provides links to major children's environmental health portals and publications within UNEP/WHO, the United Nations system, and other organizations, e.g. development agencies, academic/research and civil society.
• Data bases/indicators/standards/conventions
  Specific to key risks or issues, e.g. air, water, toxics, etc. please search by area of focus, within the web-accessible directories.