insufficient by western standards. - has no eccs. can survive at most one 4 inch pipe break ( there are many pipes greater than 4 inches within the design ). - has six steam generator loops, adding unnecessary complexity. - however, apparently steam generator loops can be isolated, in the event that a break occurs in one of these loops. the plant can remain operating with one isolated loop - a feature found in few western reactors. the interior of the pressure vessel is plain alloy steel, exposed to water. this can lead to rust, if the reactor is exposed to water. one point of distinction in which the vver surpasses the west is the reactor water cleanup facility - built, no doubt, to deal with the enormous volume of rust within the primary coolant loop - the product of the slow corrosion of the rpv. this model is viewed as having inadequate process control systems. bulgaria had a number of vver - 440 v230 models, but they opted to shut them down upon joining the eu rather than backfit them, and are instead building new vver - 1000 models. many non - eu states maintain v230 models, including russia and the cis. many of these states - rather than abandoning the reactors entirely - have opted to install an eccs, develop standard procedures, and install proper instrumentation and control systems. though confinements cannot be transformed into containments, the risk of a limiting fault resulting in core damage can be greatly reduced. the vver - 440 v213 model was built to the first set of soviet nuclear safety standards. it possesses a modest containment building, and the eccs systems, though not completely to western standards, are reasonably comprehensive. many vver - 440 v213 models possessed by former soviet bloc countries have been upgraded to fully automated western - style instrumentation and control systems, improving safety to western levels for accident prevention - but not for accident containment, which is of a modest level compared to western plants. these reactors are regarded as " safe enough " by western standards to continue operation without major modifications, though most owners have performed major modifications to bring them up to generally equivalent levels of nuclear safety. during the 1970s, finland built two vver - 440 v213 models to western standards with a large - volume full containment and world - class instrumentation, control standards and an eccs with multiply redundant and diversified components. in addition, passive safety features such as 900 - tonne ice condensers have been installed, making these two units safety - wise the most advanced vver


- class instrumentation, control standards and an eccs with multiply redundant and diversified components. in addition, passive safety features such as 900 - tonne ice condensers have been installed, making these two units safety - wise the most advanced vver - 440 ' s in the world. the vver - 1000 type has a definitely adequate western - style containment, the eccs is sufficient by western standards, and instrumentation and control has been markedly improved to western 1970s - era levels. chernobyl disaster in the chernobyl disaster the fuel became non - critical when it melted and flowed away from the graphite moderator - however, it took considerable time to cool. the molten core of chernobyl ( that part that did not vaporize in the fire ) flowed in a channel created by the structure of its reactor building and froze in place before a core - concrete interaction could happen. in the basement of the reactor at chernobyl, a large " elephant ' s foot " of congealed core material was found. time delay, and prevention of direct emission to the atmosphere, would have reduced the radiological release. if the basement of the reactor building had been penetrated, the groundwater would be severely contaminated, and its flow could carry the contamination far afield. the chernobyl reactor was an rbmk type. the disaster was caused by a power excursion that led to a meltdown and extensive offsite consequences. operator error and a faulty shutdown system led to a sudden, massive spike in the neutron multiplication rate, a sudden decrease in the neutron period, and a consequent increase in neutron population ; thus, core heat flux very rapidly increased to unsafe levels. this caused the water coolant to flash to steam, causing a sudden overpressure within the reactor pressure vessel ( rpv ), leading to granulation of the upper portion of the core and the ejection of the upper plenum of said pressure vessel along with core debris from the reactor building in a widely dispersed pattern. the lower portion of the reactor remained somewhat intact ; the graphite neutron moderator was exposed to oxygen containing air ; heat from the power excursion in addition to residual heat flux from the remaining fuel rods left without coolant induced oxidation in the moderator ; this in turn evolved more heat and contributed to the melting of the fuel rods and the outgassing of the fission products contained therein. the liquefied remains of the fuel rods flowed through a drainage pipe into the basement of the reactor building and solidified in a mass later dubbed co


to the melting of the fuel rods and the outgassing of the fission products contained therein. the liquefied remains of the fuel rods flowed through a drainage pipe into the basement of the reactor building and solidified in a mass later dubbed corium, though the primary threat to the public safety was the dispersed core ejecta and the gasses evolved from the oxidation of the moderator. although the chernobyl accident had dire off - site effects, much of the radioactivity remained within the building. if the building were to fail and dust was to be released into the environment then the release of a given mass of fission products which have aged for twenty years would have a smaller effect than the release of the same mass of fission products ( in the same chemical and physical form ) which had only undergone a short cooling time ( such as one hour ) after the nuclear reaction has been terminated. however, if a nuclear reaction was to occur again within the chernobyl plant ( for instance if rainwater was to collect and act as a moderator ) then the new fission products would have a higher specific activity and thus pose a greater threat if they were released. to prevent a post - accident nuclear reaction, steps have been taken, such as adding neutron poisons to key parts of the basement. the effects of a nuclear meltdown depend on the safety features designed into a reactor. a modern reactor is designed both to make a meltdown unlikely, and to contain one should it occur. in a modern reactor, a nuclear meltdown, whether partial or total, should be contained inside the reactor ' s containment structure. thus ( assuming that no other major disasters occur ) while the meltdown will severely damage the reactor itself, possibly contaminating the whole structure with highly radioactive material, a meltdown alone should not lead to significant radiation release or danger to the public. in practice, however, a nuclear meltdown is often part of a larger chain of disasters ( although there have been so few meltdowns in the history of nuclear power that there is not a large pool of statistical information from which to draw a credible conclusion as to what " often " happens in such circumstances ). for example, in the chernobyl accident, by the time the core melted, there had already been a large steam explosion and graphite fire and major release of radioactive contamination ( as with almost all soviet reactors, there was no containment structure at chernobyl ). also, before a possible meltdown occurs, pressure can already be rising in the reactor, and to prevent


and graphite fire and major release of radioactive contamination ( as with almost all soviet reactors, there was no containment structure at chernobyl ). also, before a possible meltdown occurs, pressure can already be rising in the reactor, and to prevent a meltdown by restoring the cooling of the core, operators are allowed to reduce the pressure in the reactor by releasing ( radioactive ) steam into the environment. this enables them to inject additional cooling water into the reactor again. reactor design although pressurized water reactors are more susceptible to nuclear meltdown in the absence of active safety measures, this is not a universal feature of civilian nuclear reactors. much of the research in civilian nuclear reactors is for designs with passive nuclear safety features that may be less susceptible to meltdown, even if all emergency systems failed. for example, pebble bed reactors are designed so that complete loss of coolant for an indefinite period does not result in the reactor overheating. the general electric esbwr and westinghouse ap1000 have passively activated safety systems. the candu reactor has two low - temperature and low - pressure water systems surrounding the fuel ( i. e. moderator and shield tank ) that act as back - up heat sinks and preclude meltdowns and core - breaching scenarios. fast breeder reactors are more susceptible to meltdown than other reactor types, due to the larger quantity of fissile material and the higher neutron flux inside the reactor core, which makes it more difficult to control the reaction. accidental fires are widely acknowledged to be risk factors that can contribute to a nuclear meltdown. united states there have been at least eight meltdowns in the history of the united states. all are widely called " partial meltdowns. " - borax - i was a test reactor designed to explore criticality excursions and observe if a reactor would self limit. in the final test, it was deliberately destroyed and revealed that the reactor reached much higher temperatures than were predicted at the time. - the reactor at ebr - i suffered a partial meltdown during a coolant flow test on november 29, 1955. - the sodium reactor experiment in santa susana field laboratory was an experimental nuclear reactor which operated from 1957 to 1964 and was the first commercial power plant in the world to experience a core meltdown in july 1959. - stationary low - power reactor number one ( sl - 1 ) was a united states army experimental nuclear power reactor which underwent a criticality excursion, a steam explosion, and a meltdown on january 3,


- the fukushima i nuclear accidents following the earthquake and tsunami in japan, march 2011. other core meltdowns have occurred at : - nrx ( military ), ontario, canada, in 1952 - borax - i ( experimental ), idaho, u. s. a., in 1954 - ebr - i ( military ), idaho, u. s. a., in 1955 - windscale ( military ), sellafield, england, in 1957 ( see windscale fire ) - sodium reactor experiment, ( civilian ), california, u. s. a., in 1959 - fermi 1 ( civilian ), michigan, u. s. a., in 1966 - chapelcross nuclear power station ( civilian ), scotland, in 1967 - saint - laurent nuclear power plant ( civilian ), france, in 1969 - a1 plant, ( civilian ) at jaslovske bohunice, czechoslovakia, in 1977 - saint - laurent nuclear power plant ( civilian ), france, in 1980 china syndrome the china syndrome ( loss - of - coolant accident ) is a fictional nuclear reactor operations accident characterized by the severe meltdown of the core components of the reactor, which then burn through the containment vessel and the housing building, then notionally through the crust and body of the earth until reaching the other side, which in the united states is jokingly referred to as being china. the system design of the nuclear power plants built in the late 1960s raised questions of operational safety, and raised the concern that a severe reactor accident could release large quantities of radioactive materials into the atmosphere and environment. by 1970, there were doubts about the ability of the emergency cooling systems of a nuclear reactor to prevent a loss of coolant accident and the consequent meltdown of the fuel core ; the subject proved popular in the technical and the popular presses. in 1971, in the article thoughts on nuclear plumbing, former manhattan project ( 1942 – 1946 ) nuclear physicist ralph lapp used the term " china syndrome " to describe a possible burn - through, after a loss of coolant accident, of the nuclear fuel rods and core components melting the containment structures, and the subsequent escape of radioactive material ( s ) into the atmosphere and environment ; the hypothesis derived from a 1967 report by a group of nuclear physicists, headed by w. k. ergen. in the event, lapp ’ s hypothetical nuclear accident was cinematically adapted as the china syndrome ( 1979 ). the geographic, planet - piercing concept of the china syndrome derives from


of nuclear physicists, headed by w. k. ergen. in the event, lapp ’ s hypothetical nuclear accident was cinematically adapted as the china syndrome ( 1979 ). the geographic, planet - piercing concept of the china syndrome derives from the misperception that china is the antipode of the united states ; to many americans, it is the “ the other side of the world ”. moreover, the hypothetical transit of a meltdown product to the other side of the earth ( i. e. china ) ignores the fact that the earth ' s gravity tends to pull all masses towards its center. assuming a meltdown product could persist in a mobile molten form for long enough to reach the center of the earth ; momentum loss due to friction ( fluid viscosity ) would prevent it continuing to the other side. see also - behavior of nuclear fuel during a reactor accident - chernobyl compared to other radioactivity releases - chernobyl disaster effects - high - level radioactive waste management - international nuclear event scale - list of civilian nuclear accidents - lists of nuclear disasters and radioactive incidents - nuclear fuel response to reactor accidents - nuclear safety - nuclear power - nuclear power debate - martin fackler ( june 1, 2011 ). " report finds japan underestimated tsunami danger ". new york times. - international atomic energy agency ( iaea ) ( 2007 ). iaea safety glossary : terminology used in nuclear safety and radiation protection ( 2007edition ed. ). vienna, austria : international atomic energy agency. isbn 92 - 0 - 100707 - 8. retrieved 2009 - 08 - 17. - united states nuclear regulatory commission ( nrc ) ( 2009 - 09 - 14 ). " glossary ". website. rockville, maryland, usa : federal government of the united states. pp. see entries for letter m and entries for letter n. retrieved 2009 - 10 - 03. - reactor safety study : an assessment of accident risks in u. s. commercial nuclear power plants, volume 1 - hewitt, geoffrey frederick ; collier, john gordon ( 2000 ). " 4. 6. 1 design basis accident for the agr : depressurization fault ". introduction to nuclear power ( in technical english ). london, uk : taylor & francis. p. 133. isbn 978 - 1 - 56032 - 454 - 6. retrieved 2010 - 06 - 05. - " earthquake report no. 91 ". jaif. may 25, 2011. retrieved may 25, 2011. - kuan,


. 133. isbn 978 - 1 - 56032 - 454 - 6. retrieved 2010 - 06 - 05. - " earthquake report no. 91 ". jaif. may 25, 2011. retrieved may 25, 2011. - kuan, p. ; hanson, d. j., odar, f. ( 1991 ). managing water addition to a degraded core. retrieved 2010 - 11 - 22. - haskin, f. e. ; camp, a. l. ( 1994 ). perspectives on reactor safety ( nureg / cr - 6042 ) ( reactor safety course r - 800 ), 1st edition. beltsville, md : u. s. nuclear regulatory commission. p. 3. 1 – 5. retrieved 2010 - 11 - 23. - haskin, f. e. ; camp, a. l. ( 1994 ). perspectives on reactor safety ( nureg / cr - 6042 ) ( reactor safety course r - 800 ), 1st edition. beltsville, md : u. s. nuclear regulatory commission. pp. 3. 5 – 1 to 3. 5 – 4. retrieved 2010 - 12 - 24. - haskin, f. e. ; camp, a. l. ( 1994 ). perspectives on reactor safety ( nureg / cr - 6042 ) ( reactor safety course r - 800 ), 1st edition. beltsville, md : u. s. nuclear regulatory commission. pp. 3. 5 – 4 to 3. 5 – 5. retrieved 2010 - 12 - 24. - ans : public information : resources : special topics : history at three mile island : what happened and what didn ' t in the tmi - 2 accident - nuclear industry in russia sells safety, taught by chernobyl - ' melt - through ' at fukushima? / govt. suggests situation worse than meltdown http : / / www. yomiuri. co. jp / dy / national / t110607005367. htm - test area north - walker, j. samuel ( 2004 ). three mile island : a nuclear crisis in historical perspective ( berkeley : university of california press ), p. 11. - lapp, ralph e. " thoughts on nuclear plumbing. " the new york times, 12 december 1971, pg. e11. - " china syndrome ". merriam - webster. retrieved december 11, 2012. - presenter : martha raddatz ( 15 march 2011 ). " abc world news ". abc. - allen


signal - to - noise ratio ( often abbreviated snr or s / n ) is a measure used in science and engineering that compares the level of a desired signal to the level of background noise. it is defined as the ratio of signal power to the noise power. a ratio higher than 1 : 1 indicates more signal than noise. while snr is commonly quoted for electrical signals, it can be applied to any form of signal ( such as isotope levels in an ice core or biochemical signaling between cells ). signal - to - noise ratio is sometimes used informally to refer to the ratio of useful information to false or irrelevant data in a conversation or exchange. for example, in online discussion forums and other online communities, off - topic posts and spam are regarded as " noise " that interferes with the " signal " of appropriate discussion. where p is average power. both signal and noise power must be measured at the same or equivalent points in a system, and within the same system bandwidth. if the signal and the noise are measured across the same impedance, then the snr can be obtained by calculating the square of the amplitude ratio : where a is root mean square ( rms ) amplitude ( for example, rms voltage ). because many signals have a very wide dynamic range, snrs are often expressed using the logarithmic decibel scale. in decibels, the snr is defined as which may equivalently be written using amplitude ratios as the concepts of signal - to - noise ratio and dynamic range are closely related. dynamic range measures the ratio between the strongest un - distorted signal on a channel and the minimum discernable signal, which for most purposes is the noise level. snr measures the ratio between an arbitrary signal level ( not necessarily the most powerful signal possible ) and noise. measuring signal - to - noise ratios requires the selection of a representative or reference signal. in audio engineering, the reference signal is usually a sine wave at a standardized nominal or alignment level, such as 1 khz at + 4 dbu ( 1. 228 vrms ). snr is usually taken to indicate an average signal - to - noise ratio, as it is possible that ( near ) instantaneous signal - to - noise ratios will be considerably different. the concept can be understood as normalizing the noise level to 1 ( 0 db ) and measuring how far the signal ' stands out '. difference from conventional power in physics power ( physics ) of an ac signal is defined as but in signal processing and communication we usually assume that


as normalizing the noise level to 1 ( 0 db ) and measuring how far the signal ' stands out '. difference from conventional power in physics power ( physics ) of an ac signal is defined as but in signal processing and communication we usually assume that so that usually we don ' t include that resistance term while measuring power or energy of a signal. this usually causes some confusions among readers but the resistance term is not significant for operations performed in signal processing. most of cases the power of a signal would be where ' a ' is the amplitude of the ac signal. in some places people just use as the constant term doesn ' t affect much during the calculations. alternative definition where is the signal mean or expected value and is the standard deviation of the noise, or an estimate thereof. [ note 2 ] notice that such an alternative definition is only useful for variables that are always non - negative ( such as photon counts and luminance ). thus it is commonly used in image processing, where the snr of an image is usually calculated as the ratio of the mean pixel value to the standard deviation of the pixel values over a given neighborhood. sometimes snr is defined as the square of the alternative definition above. the rose criterion ( named after albert rose ) states that an snr of at least 5 is needed to be able to distinguish image features at 100 % certainty. an snr less than 5 means less than 100 % certainty in identifying image details. snr for various modulation systems amplitude modulation channel signal - to - noise ratio is given by where w is the bandwidth and ka is modulation index output signal - to - noise ratio ( of am receiver ) is given by frequency modulation channel signal - to - noise ratio is given by output signal - to - noise ratio is given by improving snr in practice all real measurements are disturbed by noise. this includes electronic noise, but can also include external events that affect the measured phenomenon — wind, vibrations, gravitational attraction of the moon, variations of temperature, variations of humidity, etc., depending on what is measured and of the sensitivity of the device. it is often possible to reduce the noise by controlling the environment. otherwise, when the characteristics of the noise are known and are different from the signals, it is possible to filter it or to process the signal. for example, it is sometimes possible to use a lock - in amplifier to modulate and confine the signal within a very narrow bandwidth and then filter the detected signal to the narrow band where it resides, thereby eliminating most of the broadband noise.


. for example, it is sometimes possible to use a lock - in amplifier to modulate and confine the signal within a very narrow bandwidth and then filter the detected signal to the narrow band where it resides, thereby eliminating most of the broadband noise. when the signal is constant or periodic and the noise is random, it is possible to enhance the snr by averaging the measurement. in this case the noise goes down as the square root of the number of averaged samples. digital signals when a measurement is digitised, the number of bits used to represent the measurement determines the maximum possible signal - to - noise ratio. this is because the minimum possible noise level is the error caused by the quantization of the signal, sometimes called quantization noise. this noise level is non - linear and signal - dependent ; different calculations exist for different signal models. quantization noise is modeled as an analog error signal summed with the signal before quantization ( " additive noise " ). this theoretical maximum snr assumes a perfect input signal. if the input signal is already noisy ( as is usually the case ), the signal ' s noise may be larger than the quantization noise. real analog - to - digital converters also have other sources of noise that further decrease the snr compared to the theoretical maximum from the idealized quantization noise, including the intentional addition of dither. although noise levels in a digital system can be expressed using snr, it is more common to use eb / no, the energy per bit per noise power spectral density. the modulation error ratio ( mer ) is a measure of the snr in a digitally modulated signal. fixed point assuming a uniform distribution of input signal values, the quantization noise is a uniformly distributed random signal with a peak - to - peak amplitude of one quantization level, making the amplitude ratio 2n / 1. the formula is then : this relationship is the origin of statements like " 16 - bit audio has a dynamic range of 96 db ". each extra quantization bit increases the dynamic range by roughly 6 db. assuming a full - scale sine wave signal ( that is, the quantizer is designed such that it has the same minimum and maximum values as the input signal ), the quantization noise approximates a sawtooth wave with peak - to - peak amplitude of one quantization level and uniform distribution. in this case, the snr is approximately floating point note that the dynamic range is much larger than fixed - point,


then can be calculated from data where the signal is zero or relatively constant. - often special filters are used to weight the noise : din - a, din - b, din - c, din - d, ccir - 601 ; for video, special filters such as comb filters may be used. - maximum possible full scale signal can be charged as peak - to - peak or as rms. audio uses rms, video p - p, which gave + 9 db more snr for video. - michael a. choma, marinko v. sarunic, changhuei yang, joseph a. izatt. sensitivity advantage of swept source and fourier domain optical coherence tomography. optics express, 11 ( 18 ). sept 2003. - d. j. schroeder ( 1999 ). astronomical optics ( 2nd ed. ). academic press. p. 433. isbn 978 - 0 - 12 - 629810 - 9. - bushberg, j. t., et al., the essential physics of medical imaging, ( 2e ). philadelphia : lippincott williams & wilkins, 2006, p. 280. - rafael c. gonzalez, richard eugene woods ( 2008 ). digital image processing. prentice hall. p. 354. isbn 0 - 13 - 168728 - x. - tania stathaki ( 2008 ). image fusion : algorithms and applications. academic press. p. 471. isbn 0 - 12 - 372529 - 1. - jitendra r. raol ( 2009 ). multi - sensor data fusion : theory and practice. crc press. isbn 1 - 4398 - 0003 - 0. - john c. russ ( 2007 ). the image processing handbook. crc press. isbn 0 - 8493 - 7254 - 2. - defining and testing dynamic parameters in high - speed adcs — maxim integrated products application note 728 - fixed - point vs. floating - point dsp for superior audio — rane corporation technical library - taking the mystery out of the infamous formula, " snr = 6. 02n + 1. 76db, " and why you should care. analog devices - adc and dac glossary – maxim integrated products - understand sinad, enob, snr, thd, thd + n, and sfdr so you don ' t get lost in the noise floor – analog devices - the relationship of dynamic range to data word size in digital audio processing - calculation


july 24, 2011 the photo above shows a lovely group of mushrooms nestled against the trunk of a eucalyptus tree. the association between the fungi and the tree however is no accident. this is a mutualistic relationship, where the two species assist each other, and in fact probably would be poorer without each other. mutualism is any relationship between two species of organisms that benefits both species. up to a quarter of the mushrooms you see while walking through the woods actually make their living through a mutualistic relationship with the trees in the forest. remember of course that the mushroom is just the reproductive structure of a far more extensive organism consisting of a highly intertwined mass of fine white threads called a mycelium. the word mycorrhiza is derived from the classical greek words for " mushroom " and " root. " in a mycorrhizal association, the fungal hyphae of an underground mycelium are in contact with plant roots but without the fungus parasitizing the plant. while it ' s clear that the majority of plants form mycorrhizas, the exact percentage is uncertain, but it ' s likely to lie somewhere between 80 and 90 percent. when the fungus ’ mycelium envelopes the roots of the tree the effect is to greatly increase the soil area covered by the tree ’ s root system. this essentially extends the plant ’ s reach to water and nutrients, allowing it to utilize more of the soil ’ s resources. this mutualistic association provides the fungus with a relatively constant and direct access to carbohydrates, such as glucose and sucrose, supplied by the plant. in return the plant gains the benefits of the mycelium ' s higher absorptive capacity for water and mineral nutrients ( due to comparatively large surface area of mycelium - to - root ratio ), thus improving the plant ' s mineral absorption capabilities. photo taken on may 7, 2011. photo details : camera maker : canon ; camera model : canon eos 50d ; focal length : 70. 0mm ; aperture : f / 10. 0 ; exposure time : 0. 013 s ( 1 / 80 ) ; iso equiv : 1250 ; exposure bias : - 1. 00 ev ; metering mode : matrix ; exposure : aperture priority ( semi - auto ) ; white balance : auto ; flash fired : no ( enforced ) ; orientation : normal ; color space : srgb.


peel - and - stick solar cells available in near future the nrel and stanford are teaming up to develop peel - and - stick solar cells, which could become devices to charge battery operated products, such as cell phones, in the future. peel - and - stick, or water - assisted transfer printing ( wtp ), technologies were developed by the stanford group and have been used before for nanowire based electronics, but the stanford - nrel ( u. s. department of energy ’ s national renewable energy laboratory ) partnership has conducted the first successful demonstration using actual thin film solar cells. the university and nrel showed that thin - film solar cells less than one - micron thick can be removed from a silicon substrate used for fabrication by dipping them in water at room temperature. then, after exposure to heat of about 90°c for a few seconds, they can attach to almost any surface. nrel ’ s cells could be made easily on stanford ’ s peel off substrate. nrel ’ s amorphous silicon cells were fabricated on nickel - coated si / sio2 wafers. a thermal release tape attached to the top of the solar cell serves as a temporary transfer holder. an optional transparent protection layer is spin - casted in between the thermal tape and the solar cell to prevent contamination when the device is dipped in water. the result is a thin strip much like a bumper sticker : the user can peel off the handler and apply the solar cell directly to a surface. the cells ’ ability to adhere to a universal substrate is unusual ; most thin - film cells must be affixed to a special substrate. the peel - and - stick approach allows the use of flexible polymer substrates and high processing temperatures. the resulting flexible, lightweight, and transparent devices then can be integrated onto curved surfaces such as military helmets and portable electronics, transistors and sensors.


onto a wide range of roofs - white paint is typically cheaper than dark paint - it is a win - win solution that gives an effective action plan that many people can do themselves instead of waiting for others to take action. i have written elsewhere in happyzine about the science and benefits and simplicity of white roofs so i won ’ t repeat it in this article. a couple of studies have compared both white roofs and green roofs with traditional dark roofs, such as one carried out at the university of columbia ’ s centre for climate systems research in 2010, which was commissioned by con edison, one of the largest energy companies in the us. an earlier study was carried out by walmart, the largest retailer in the us. thanks to the following environmentally responsible businesses for supporting happyzine : nelson ’ s busy organic shop – healthy food, happy people, great service, caring for the environment. corner tasman & grove streets, nelson. ph 03 548 3650. the columbia study found that both white and green roofs perform equally well in preventing the heat island effect, which is the heat concentration found in many cities resulting from replacing vegetation with man - made buildings and roads that absorb sunlight and convert it into heat. the study was carried out on adjacent roofs of con edison. the green roof ( using 21, 000 plants ), the white roof and the dark roof each had embedded sensors to measure heat flows through the roof structure. it was found that both white roofs and green roofs produced significant energy savings compared to a standard dark roof, that the green roof savings were greater than the white, which is to be expected considering the amount of insulation 150 mm of soil would provide. note that these studies did not include for the amount of global cooling produced by the white roofs directly reflecting sunlight back into space, which green roofs do not offer, and which has been found to be a very effective mechnism for global warming reduction in other studies with that focus. the emphasis of the columbia study was more focused on energy savings that also put money in your pocket, and did not include for global cooling of the planet. the goal of the study was to provide the best science to help these companies make choices and cost - benefit estimates in how they might achieve better energy efficiency. which perhaps gives understanding to why companies like con edison and walmart have embraced white roofs, with con edison having installed 25, 000 square metre of white roof at the time this report was written, with at least a further 22, 000 m2 planned by the end of 2010, and walmart has had a


nonperishable food collection - the collection of processed foods with long shelf lives. - food banks provide food to other organizations like food pantries, soup kitchens, hunger relief centers, or other food or feeding centers. usually, food banks do not distribute food directly to individuals. - food pantries distribute food to low - income and unemployed households to take home. - soup kitchens provide meals to the needy and the homeless on a regular basis. in addition to perishable and non - perishable commercial foods donated by retailers, manufacturers, food service establishments, etc., many of the agencies listed in this booklet distribute usda commodities made available through the emergency food assistance program ( tefap ). under tefap, commodity foods are distributed to organizations ( i. e., soup kitchens ) in the state that use them in congregate feeding facilities for the needy, including the homeless, and to organizations ( i. e., food pantries ) that provide them to eligible households for home consumption. to be eligible to take commodities home, households must meet established income requirements or participate in another government program such as food stamps, temporary assistance for needy families ( tanf ), supplemental security income ( ssi ) ; medicaid, or reside in public housing. there are many worthwhile organizations, not included in this booklet, that provide food assistance directly to the needy. contact the local food bank to find the location of a food pantry or soup kitchen in your area. to obtain contact information go to the second harvest website and enter your zip code where it says " find your local food bank or food rescue organization. " the operation of a good food recovery program is three - fold : - locate unsold or unmerchantable food and fresh produce. - coordinate its transportation and storage. - distribute it to the needy. there are various ways to get involved in the fight against hunger and demonstrate commitment to the community. food service professionals - organize a food drive and donate food to a local food bank or pantry. - donate excess prepared food from restaurants, school cafeterias or catered events. - assist organizations in training their volunteers in safe food - handling practices. - work independently or with existing organizations to assist ongoing food recovery efforts. - support or develop a community or regional coalition against hunger. - develop a community financial fund to fight hunger. - plan tours of food recovery facilities or arrange for knowledgeable speakers to increase community awareness of hunger and poverty problems, and what people are doing to address them. youth service groups and


in sections is costly because of the labor and time involved, and leaves overlaps in the coating that can become failure points over time. ” mudri contacted jeff cox, lead industrial technician for the northern united states region for polygon, to design a system to control moisture and temperature during the blasting and coating process. cox analyzed the project ' s parameters and recommended a combination of dehumidification and heat to maintain ideal blasting and coating conditions. polygon technicians delivered a 4500 - cfm desiccant dehumidifier and two inline electric heaters from the company ' s plaistow, n. h., office and configured the equipment near the tanks. polygon personnel used ductwork to connect the climate - control equipment to the tanks via manways at the base of each structure. once operational, the equipment provided a dew - point differential of 17°f and steel - surface temperatures of 50°f. this allowed g. c. zarnas to blast an entire tank before coating it. “ the larger tanks took up to a week to sandblast, ” cox said. “ after sandblasting, the tank was cleaned and then the coating was applied. ” “ without the proper climate, we would have had to put a coat of paint or primer on each day after finishing to prevent rust, ” mudri said. “ it would have taken much longer — possibly twice as long — because we would have to sandblast, clean, and then paint. ” mudri said work continued even with temperatures dropping significantly during the harsh new england winter. “ it was a brutal winter with temperatures below zero at times, ” mudri said. “ even so, conditions inside the tank were always at the necessary standard and the project was completed as planned. ” information and photograph courtesy of polygon.


an alternative to salt - based water softening although the varied climatic conditions along california ' s central coast, home of hahn family wines, are ideal for the growing of grapes, the water underground, which the vintner uses for closed - loop heat - cleaning of fermenting barrels and bottles, is mineral - rich and scale - producing. gritty deposits collect and become troublesome with the application of heat. after years of using salt - based water softening for critical boiler - treatment applications, hahn family wines sought an environmentally friendlier form of water treatment, one free of chemicals, salt, and waste discharge. for its main water supply, it commissioned the installation of a template - assisted - crystallization ( tac ) central treatment system. tac falls into a category often referred to as “ physical water treatment ” ( pwt ). the primary goals of pwt are to : avoid the use of chemical additives. minimize or avoid discharge water, regenerates, and waste water. avoid pollution and disposal costs. minimize capital costs and ongoing maintenance. the technology behind tac treatment systems was developed in germany about 15 years ago and used throughout europe before coming to the united states about eight years ago. tac media start out as polymeric beads ( resin ) in the 20 - to - 40 - mesh size range. catalytically active sites, or templates, are imprinted on the beads ' surface through a batch - coating process. pwt works by changing the physical characteristics of a solution, with little or no change in the solution ' s chemical composition. pwt is used chiefly to reduce water hardness ( calcium carbonate ) in plumbing systems, appliances, and equipment ( boilers, water heaters, dish washers, automotive - and process - washing equipment ), valves, and other components that generate or use heated water. most pwt devices promote hardness crystallization in a bulk solution to prevent scale formation on downstream surfaces. tac is technology that influences a water solution at localized sites ( on the media surface ) so that hardness ions and their counter - ions ( bicarbonate ) combine to form inert nanometer - size “ seed crystals. ” called nucleation, this is the process by which dissolved molecules or ions dispersed throughout a solution gather to create clusters in the submicron size range. the sum of the seeds provides an enormous area for preferential growth of remaining hardness ions still in solution. making use of the phenomenon of low - energy heterogeneous transfer, by which solubility shift is achieved, the


what is the basic foundation for a family unit? a family is more than a household unit. in the bible, every family represented a microcosm of the community within which it lived. therefore, when families failed, the community itself failed. in times of crisis, families were relied upon to support and strengthen the community. for example, moses was charged to offer the following order to his followers : " make sure there isn ' t a man or woman among your families or tribes who turns away from the lord our god ( deuteronomy 29 : 18 ). " the family served as a keeper of the core values of the community in which it lived. thus, family is something more than a household unit. a family is more than a political or religious concept. according to the bible, " family " is not a man - made concept. rather, it originates from the mind of god. as recorded in the book of genesis, family is an intentional creation of the creator, and it is directly blessed by god. no sooner after god create man and woman that he blessed them and told them to create a family : " god blessed them, " states genesis 1 : 28, continuing, " he said to them, ' have children and increase your numbers. ' " the concept of family predates politics and organized religions. so, rather than simply being a political or religious concept, family is an undeniably divine concept. a family is more than an old testament biblical teaching. even deep into the new testament, the concept of family is valued as a foundation that was especially designed by god. paul verifies this fact in his letter to the ephesians, commenting, " i bow my knees unto the father of our lord jesus christ, from whom the whole family in heaven and earth is named ( ephesians 3 : 14 - 15 ). " the new testament reminds us that you will find families in heaven and earth, and in ancient and modern day times. families are a universal concept that supersedes the old testament. what is a family? it is an important part of today ' s society. family is more than a domestic unit that is only defined by the number of parents and children. it connects us to others outside of our households. your bloodline is only one part of your family construct. although your family unit is defined by you, it is measured by your community. your culture, religion, and language are also important ingredients and they will bind you with others of like conviction. family is natural and spiritual


giuseppe donati invented the modern 10 - hole ocarina. although oceanography has been recognized as a formal scientific discipline for only 150 years, the quest for this understanding and its practical application to commerce and war - often unwitting - goes back much further. history of the odometer. in the late 19th century, commercial offices for conducting business first appeared in the united states. see also - office machinary ellen ochoa invented the optical analysis system. tuan vo - dinh invented optical diagnostic equipment. vo - dinh ' s patents were for a badge worn on a worker ' s shirt that recorded exposure to toxic chemicals and for a optical scanner that would read that badge. david paul gregg first envisioned the optical or laser disc in 1958 and patented it in 1969. the inventors behind the first oral contraceptives. dr wilhelm reich invented the orgone accumulator. today ' s dynamic o - ring was the result of experimental work done in the early 1930 ' s by mr. niels christensen. ole evinrude invented the outboard motor. the first historical record of an oven being built refers to a stove built in 1490 made entirely of brick and tile. if you cannot find what you want by invention, try by the inventor.


the bavli, chulin 60 : 2, says ( in my own loose translation ) : rabbi shim ' on ben pazi noted a contradiction : [ b ' reshis 1 : 16 ] says, " god made the two big luminaries " and " the big luminary … and the small luminary ". the moon said to god : " master of the world, is it possible for two kings to use one crown? " he told her : " go diminish yourself. " she told him : " master of the world, because i said something proper to you i have to diminish myself? " he told her : " go and rule [ = shine ] by day and night. " ( and the conversation continued further. ) presumably this midrash is not meant literally. ( moons don ' t talk, for one thing. ) but my question will assume it ' s literal. in other words, my question will be about the storyline of the midrash, assuming its premise. my question is : in what sense was the moon diminished? here are the two most reasonable possibilities i can see : - the sun and moon were the same size ( say, a million kilometers ' diameter, like the sun is now ), and the moon shrank to the 3500 kilometers ' diameter it is now. - the sun and moon were the same apparent size as viewed from earth ( same angular diameter ) — as they are in fact now! — and the moon shrank in the sense that now it wanes.


you can ' t touch it, but it affects how you feel. you can ' t see it, but it might be there when you look at yourself in the mirror. you can ' t hear it, but it ' s there when you talk about yourself or when you think about yourself. what is this important but mysterious thing? it ' s your self - esteem! what is self - esteem? self - esteem can have a big part to play in how you feel about yourself and also how much you enjoy things or worry about things. to understand self - esteem, it helps to break the term into two words. let ' s first take a look at the word esteem ( say : ess - teem ), which means that someone or something is important, special, or valuable. for example, if you really admire your friend ' s dad because he volunteers at the fire department, it means you hold him in high esteem. and the special trophy for the most valuable player on a team is often called an esteemed trophy. this means the trophy stands for an important accomplishment. and self means, well, yourself! so put the two words together and it ' s easier to see what self - esteem is. it ' s how much you value yourself and how important you think you are. it ' s how you see yourself and how you feel about the things you can do. self - esteem isn ' t about bragging, it ’ s about getting to know what you are good at and not so good at. a lot of us think about how much we like other people or things, but don ' t really think much about whether we like ourselves. it ' s not about thinking you ' re perfect, because nobody is perfect. even if you think some other kids are good at everything, you can be sure they have things they ' re good at and things that are difficult for them. the most important thing to know about self - esteem is that it means seeing yourself in a positive way that ' s realistic, which means that it ' s the truth. so if you know you ' re really good at piano but can ' t draw so well, you can still have great self - esteem! self - esteem isn ' t like a cool pair of sneakers you really want but can wait until your next birthday to get. all kids have self - esteem, and having healthy or positive self - esteem is really important. it can help you hold your head high and feel proud of yourself and what you can do, even when things


many things just seem to come naturally to some people. maybe you know a girl who ' s a natural at sports — put her in a uniform and she ' s off and running. some people are naturals at playing an instrument ; it ' s like they were born knowing how to count in 4 / 4 time. others are naturals at math ; give them a test on theorems or equations and they ' re happy. but some people have a problem with something that you ' d think would come naturally to everyone : breathing. when someone has asthma, it can make breathing very difficult. and when it ' s hard to breathe, it can affect a person ' s game, that trumpet solo, and even the all - important geometry test. what is asthma? asthma ( pronounced : az - muh ) is a lung condition that causes difficulty breathing. asthma is a common condition : about 7 million kids and teens in the united states have it. asthma affects the bronchial ( pronounced : brahn - kee - ul ) tubes, also known as airways. when a person breathes normally, air is taken in through the nose or mouth and then goes into the trachea ( windpipe ), passing through the bronchial tubes, into the lungs, and finally back out again. but people with asthma have airways that are inflamed. this means that they swell and produce lots of thick mucus. they are also overly sensitive, or hyperreactive, to certain things, like exercise, dust, or cigarette smoke. this hyperreactivity causes the smooth muscle that surrounds the airways to tighten up. the combination of airway inflammation and muscle tightening narrows the airways and makes it difficult for air to move through. in most people with asthma, the difficulty breathing happens periodically. when it does happen, it is known as an asthma flare - up also known as an asthma attack, flare, episode, or exacerbation. someone having an asthma flare - up may cough, wheeze ( make a whistling sound while breathing ), be short of breath, and feel an intense tightness in the chest. many people with asthma compare a flare - up to the sensation of trying to breathe through a straw — it feels extremely hard to get air in and out of their lungs. an asthma flare - up can last for several hours or longer if a person doesn ' t use asthma medication. when an asthma flare - up is over, the person usually feels better. between flare - ups, breathing can seem completely normal


kottke. org posts about pimovie pi, god, and apartment supercomputers jul 18 2005 the new yorker recently ran a feature on how a couple of mathematicians helped the met photograph a part of the hunt of the unicorn tapestries. that same week, they ran from their extensive archives a 1992 profile of the same mathematicians, brothers david and gregory chudnovsky. the chudnovskys were then engaged in calculating as many digits of pi as they could using a homemade supercomputer housed in their manhattan apartment. there ' s some speculation that director darren aronfsky based his 1998 film, pi, on the chudnovskys and after reading the above article, there ' s little doubt that ' s exactly what he did : they wonder whether the digits contain a hidden rule, an as yet unseen architecture, close to the mind of god. a subtle and fantastic order may appear in the digits of pi way out there somewhere ; no one knows. no one has ever proved, for example, that pi does not turn into nothing but nines and zeros, spattered to infinity in some peculiar arrangement. if we were to explore the digits of pi far enough, they might resolve into a breathtaking numerical pattern, as knotty as " the book of kells, " and it might mean something. it might be a small but interesting message from god, hidden in the crypt of the circle, awaiting notice by a mathematician. the chudnovsky article also reminds me of contact by carl sagan in which pi is prominently featured as well. according to wolfram research ' s mathworld, the current world record for the calculation of digits in pi is 1241100000000 digits, held by japanese computer scientists kanada, ushio and kuroda. kanada is named in the article as the chudnovskys main competitor at the time. ( oh, and as for patterns hidden in pi, we ' ve already found one. it ' s called the circle. just because humans discovered circles first and pi later shouldn ' t mean that the latter is derived from the former. )


substances bioflavonoids ( or flavonoids ) are plant substances that bring color to many fruits and vegetables. citrus fruits are a rich source of bioflavonoids, including diosmin, hesperidin, rutin, and naringen ; studies have found these bioflavonoids may help decrease bruising. two types of natural compounds related to bioflavonoids — opcs ( oligomeric proanthocyanidins ) and anthocyanosides — have also shown promise for decreasing the tendency to bruise. anthocyanosides, which are present in high concentrations in bilberry, may also strengthen capillaries through their effects on collagen. some european physicians believe that these vessel - stabilizing properties make bilberry useful as a treatment for easy bruising, but the evidence as yet is only suggestive. vitamin c is essential for healthy collagen ; severe vitamin c deficiency, called scurvy, can lead to easy bruising. fortunately, scurvy is extremely rare in western countries today — but marginal vitamin c deficiency is not rare, and might lead to increased risk of bruising. if your diet is low in fresh fruits and vegetables, you may wish to supplement it with vitamin c. in the study mentioned above, bruising in elderly people decreased significantly with 1 g of oral vitamin c given daily for 2 months. for more information, including dosage and safety issues, see the full vitamin c article. trypsin and chymotrypsin for more information, including dosage and safety issues, see the full proteolytic enzymes article. for more information, including dosage and safety issues, see the full horse chestnut article. other proposed natural treatments for more information, including dosage and safety issues, see the full bromelain article. other herbs used for bruising the herbs comfrey, arnica, and sweet clover are widely used externally on bruises and other minor injuries, but despite this traditional use, there is no real scientific evidence that they work. note : there are various safety concerns involved in using comfrey, arnica, and sweet clover internally. for the treatment of bruising, they are used as topical ointments and salves. for a discussion of homeopathic approaches to easy bruising, see the chapter on bruises in the homeopathy database - reviewer : ebsco cam review board - review date : 07 / 2012 - - update date : 07 / 25


mind - body medicine and stress management tradition - tested therapies for modern lives by marcia murphy, lcsw what is mind - body medicine? mind - body medicine explores the influence of the mind and emotions on the body and immune system, and vice versa. mind - body specialists are typically therapists or other mental health professionals who examine the effects of the mind – thoughts, attitudes and beliefs – on physical health and well - being. specialists use a variety of techniques to promote health, such as talk therapy, deep breathing, guided imagery, relaxation therapy, meditation and yoga. using these techniques, mind - body medicine helps direct energies toward healing and health. psychoneuroimmunology ( pni ), according to dr. kenneth pelletier, is “ the study of the intricate interaction of consciousness ( psycho ), brain and central nervous system ( neuro ), and the body ’ s defenses against external infection and internal aberrant cell division ( immunology ). ” dr. pelletier serves as a medical and business consultant to the united states department of health and human services, the world health organization and major corporations, such as ibm and disney. when we are under stress, our immune system becomes suppressed and our natural ability to fight disease is compromised unless we take steps to manage the stress in our lives. mental strength and physical strength are interconnected. dr. candace pert, the author of molecules of emotion and a research professor in the department of physiology and biophysics at georgetown university medical center in washington, d. c., expressed it well when she wrote, “ the body isn ’ t there simply to carry the head. ” her research has shown that “ when emotions are expressed, that is to say, when the biochemicals that are the substrate of emotion are flowing freely, all systems are united and made whole. when emotions are repressed, denied or not allowed to be whatever they may be, our network pathways get blocked, stopping the flow of the vital, “ feel - good, ” unifying chemicals that run both our biology and our behavior. ” “ stress makes you physically sick, ” explains steven maier, professor of psychology at the university of colorado. researchers know that behavioral and psychological events can influence the immune system. the immune system sends signals to the brain “ that potently alter neural activity and, thereby, alter everything that flows from neural activity, mainly behavior, thought and mood, ” said maier. the immune system also activates a classic stress response, releasing stress hormones such as


to the brain “ that potently alter neural activity and, thereby, alter everything that flows from neural activity, mainly behavior, thought and mood, ” said maier. the immune system also activates a classic stress response, releasing stress hormones such as cortisol. not only does stress produce the expected biochemical stress response, it also produces predictable behavioral changes, including decreased food and water intake. ancient wellness traditions have understood the mind - body interaction for centuries and have incorporated it into their approaches and therapies. in india for example, the yogic philosophy teaches that the body, breath, emotion and mind are inextricably linked. the chinese systems of qi gong and tai chi have also taught this principle for centuries. mind - body medicine can benefit a cancer patient by ensuring that the patient understands that he / she is not defined by the illness. at cancer treatment centers of america® patients are treated as whole persons, and are surrounded by a multi - disciplinary team of experts, including a medical oncologist, registered dietician, naturopathic physician, chiropractor and mind - body therapist. we encourage our patients who participate in our mind - body therapies to take advantage of the stress management techniques we offer. some of those techniques include : allowing an objective third party to listen to a patient ’ s feelings can be life changing. a therapist may be able to point out distorted thinking and re - orient the patient toward a more positive and helpful direction. dr. andrew weil said, “ improper breathing is a common cause of ill health. if i had to limit my advice on healthier living to just one tip, it would be simply to learn how to breathe correctly. there is no single more powerful – or more simple – daily practice to further your health and well - being than breath work. ” this is one of the greatest and quickest activities for reducing stress. laughter works because it gets your brain thinking and working in a different way. it distracts you from having a stressed mindset. as you start to smile and chuckle, the stress begins to dissipate. keep taking the laughter medicine until you feel relaxed and recharged. rest is essential for a healthy life - balance. adults need seven to nine hours of sleep each night. only in very recent times have modern heating, lighting, and communication and entertainment technologies enabled and encouraged us to keep unnatural waking and working hours. this behavior is at odds with our biological preferences. this strategy builds on deep breathing, and takes it a step further


in very recent times have modern heating, lighting, and communication and entertainment technologies enabled and encouraged us to keep unnatural waking and working hours. this behavior is at odds with our biological preferences. this strategy builds on deep breathing, and takes it a step further. when you meditate, your brain initiates a sort of functioning that is similar to sleep, but carries some added benefits that aren ’ t achieved in any other state, such as the release of certain hormones. the practice of guided imagery is somewhat more time - consuming, but is a great way to reduce stress and relax the body. some people find it easier to practice guided imagery than meditation, because it is easier to focus on something rather than on nothing. playing natural sounds in the background during guided imagery promotes a more immersive experience. progressive muscle relaxation : tensing, then releasing, all the muscle groups in the body can produce feelings of increased relaxation in minutes, with no special training or equipment. start by tensing all the muscles of the face, hold a tight grimace for ten seconds, then completely relax for ten seconds. repeat this procedure in the neck area, then the shoulder area, and so on, throughout the rest of the body. listening to music results in numerous health benefits for people with a range of conditions, both mild and severe. studies have shown that listening to certain classical music can help lower blood pressure, relieve muscle tension and promote deep breathing. the array of stress management techniques – from acupuncture to walking – is extensive enough to provide something that will appeal to, and work for, just about everyone. marcia murphy, lcsw, is a mind - body therapist at cancer treatment centers of america ( ctca ) at western regional medical center. murphy joined the mind - body medicine department at ctca in 2010 after a deeply personal experience with cancer.


produced and more and more their receptors become resistant. body fat, being an organ of storage, eventually receives the calories unable to be delivered by other insulin receptors. and as more and more calories are stored in fat, new fat cells are created and the cycle continues. the primal eating plan prioritizes protein, which comes from a greek root meaning “ of prime importance ”, because of its role in cellular repair, cellular health, and muscular growth and maintenance. there are varying sources and opinions on the quantity of protein an individual “ should ” take in everyday, but among sources which i read and trust, it is generally accepted that 1 gram of protein per pound of lean body mass ( lbm ) is a good aim, while recommendations range from. 8 grams per pound of lbm to 1 gram per pound of mass. these are good ranges to just keep in mind when thinking of what to eat on a weekly basis and what major foods to consider at the grocery store. lean body mass is calculated by determining your body fat percentage and total weight, and subtracting that body fat percentage in pounds of total mass from total mass. the number of pounds left over after body fat pounds have been subtracted from total weight is lean body mass, or the muscle and non - fat tissue of the body. there are various professional services available, which should be researched first, that can help determine these numbers for an individual. fat is also of prime importance within the primal blueprint eating plan. dietary fat plays an important role in every process of the body, being necessary for brain health, where it constitutes estimates of 60 - 70 percent of the brain, necessary for cellular generation, and necessary for organ and hormonal health. fats do provide 9 calories per gram, which is where the notorious “ fat makes you fat ” arose from, among other chemical reactions within the body. but with an individual gram of fat ’ s nine calories, comes nutrition necessary for the aforementioned functions, necessary fat - soluble vitamins, and satiety that limits excess caloric consumption and “ sweet tooth ” expenditures. carbohydrate may come off as the enemy of all things healthy in preliminary discussion of the primal eating plan, but further reading, discussion, and research will explain the importance of even carbohydrate in the diet. it is not carbohydrate that is the enemy, it is the excess of it, and the consequential unique reactions of its excess ( possibly insulin resistance ) that are of concern.


, small local paper - making businesses, etc. there was also room for small economic success with the " inn keeper, the petty diviner, the drug seller, the cloth trader, " and many others. rural families that sold a large agricultural surplus to the market not only could afford to buy more charcoal, tea, oil, and wine, but they could also amass enough funds to establish secondary means of production for generating more wealth. besides necessary agricultural foodstuffs, farming families could often produce wine, charcoal, paper, textiles, and other goods they sold through brokers. farmers in suzhou often specialized in raising bombyx mori to produce silk wares, while in fujian, sichuan, and guangdong farmers often grew sugarcane. in order to ensure the prosperity of rural areas, technical applications for public works projects and improved agricultural techniques were essential. the system of china had to be furnished with multitudes of wheelwrights and square - pallet chain pumps that could lift water from lower planes to higher irrigation planes. for clothing, silken robes worn by the wealthy and elite while hemp was worn by the poor ; by the late song clothes were also in use. shipment of all these materials and goods was aided by the 10th century innovation of the canal pound in china ; the song scientist and statesman shen kuo ( 1031 – 1095 ) wrote that the building of pound lock gates at zhenzhou ( presumably kuozhou along the yangtze ) during the 1020s and 1030s freed up the use of five hundred working laborers at the canal each year, amounting to the saving of up to 1, 250, 000 strings of cash annually. he wrote that the old method of hauling boats over limited the size of the cargo to 300 tan of rice per vessel ( roughly 21 tons / 21337 kg ), but after the pound locks were introduced, boats carrying 400 tan ( roughly 28 tons / 28449 kg ) could then be used. shen wrote that by his time ( c. 1080 ) government boats could carry cargo weights of up to 700 tan ( 49½ tons / 50294 kg ), while private boats could hold as much as 800 bags, each weighing 2 tan ( i. e. a total of 113 tons / 114813 kg ). sea trade abroad to the south east, the hindu world, and the east african world brought merchants great fortune. although the massive amount of indigenous trade along the grand canal, river, its tributaries and lakes, and other canal systems trumped the commercial gains of overseas trade


it on maritime trade missions abroad : [ song era ] investors usually divided their investment among many ships, and each ship had many investors behind one observer thought eagerness to invest in overseas trade was leading to an outflow of copper cash. he wrote, " people along the coast are on intimate terms with the merchants who engage in overseas trade, either because they are fellow - countrymen or personal acquaintances... [ they give the merchants ] money to take with them on their ships for purchase and return conveyance of foreign goods. they invest from ten to a hundred strings of cash, and regularly make profits of several hundred percent. " wealthy landholders were still typically those who were able to educate their sons to the highest degree. hence small groups of prominent families in any given local county would gain national spotlight for having sons travel far off to be educated and appointed as ministers of the state. yet downward social mobility was always an issue with the matter of divided inheritance. suggesting ways to increase a family ' s property, yuan cai ( 1140 – 1190 ) wrote in the late 12th century that those who obtained office with decent salaries shouldn ' t convert it to gold and silver, but instead could watch their values grow with investment : for instance, if he had 100, 000 strings worth of gold and silver and used this money to buy productive property, in a year he would gain 10, 000 strings ; after ten years or so, he would have regained the 100, 000 strings and what would be divided among the family would be interest. if it were invested in a pawn broking business, in three years the interest would equal the he would still have the 100, 000 strings, and the rest, being interest, could be divided. moreover, it could be doubled again in another three years, ad infinitum. ( 1031 – 1095 ), a minister of finance, was of the same opinion ; in his understanding of the velocity of circulation, he stated in 1077 : the utility of money derives from circulation and loan - making. a village of ten households may have 100, 000 coins. if the cash is stored in the household of one individual, even after a century, the sum remains 100, 000. if the coins are circulated through business transactions so that every individual of the ten households can enjoy the utility of the 100, 000 coins, then the utility will amount to that of 1, 000, 000 cash. if circulation continues without stop, the utility of the cash will be beyond the author zhu yu wrote in his (


a. d. 220, 545 - 607. edited by denis twitchett and michael loewe. cambridge : cambridge university press. isbn 0521243270. - shen, fuwei ( 1996 ). cultural flow between china and the outside world. beijing : foreign languages press. isbn - smith, paul j. ( 1993 ) " state power and economic activism during the new policies, 1068 – 1085 ' the tea and horse trade and the ' green sprouts ' loan policy, " in ordering the world : approaches to state and society in sung dynasty china, ed. robert p. hymes, 76 – 128. berkeley : berkeley university of california press. isbn - temple, robert. ( 1986 ). the genius of china : 3, 000 years of science, discovery, and invention. with a forward by joseph needham. new york : simon and schuster, inc. isbn 0671620282. - wagner, donald b. " the administration of the iron industry in eleventh - century china, " journal of the economic and social history of the orient ( volume 44 2001 ) : 175 - 197. - walton, linda ( 1999 ). academies and society in southern sung china. honolulu : university of hawaii press. - west, stephen h. " playing with food : performance, food, and the aesthetics of artificiality in the sung and yuan, " harvard journal of asiatic studies ( volume 57, number 1, 1997 ) : - yang, lien - sheng. " economic justification for spending - an uncommon idea in traditional china, " harvard journal of asiatic studies ( volume 20, number 1 / 2, 1957 ) : 36 – 52. - yunming, zhang ( 1986 ). isis : the history of science society : ancient chinese sulfur manufacturing processes. chicago : university of chicago press. - zhou qufei, ( 1178 ) ling wai dai da ( report from lingnan ), zhong hua book co isbn7 - 101 - 01665 - 0 / k


visualizing 1 + 1 / x date : 10 / 10 / 2003 at 21 : 25 : 38 from : mary subject : logic how can i show that the sum of a positive number and its reciprocal is at least two? date : 10 / 11 / 2003 at 06 : 06 : 27 from : doctor luis subject : re : logic hi mary, adding a positive number x > 0 and its reciprocal 1 / x gives you the function f ( x ) = x + 1 / x if you ' re familiar with calculus, you can see that solving for the extrema points gives you f ' ( x ) = 1 - 1 / x ^ 2 = 0 1 = 1 / x ^ 2 x ^ 2 = 1 x = 1 ( reject negative root since x > 0 ) since f " ( x ) = 2 / x ^ 3 is positive for x > 0, we know that f ( x ) is concave upward. this means that the critical point x = 1 gives you a minimum. this minimum value is f ( 1 ) = 1 + 1 / 1 = 2. in the following diagram, i ' ve graphed the two functions y = x + 1 / x and y = 2. even if you are not familiar with calculus maybe you can follow the following chain of reasoning : the square of any nonzero real number is positive. as an inspired guess, pick x - 1 as the real number to be squared. then, ( x - 1 ) ^ 2 > = 0 ( true for all x. equality holds only for x = 1. ) x ^ 2 - 2x + 1 > = 0 x ^ 2 + 1 > = 2x now, let x > 0, since we are only interested in positive numbers. this means that 1 / x > 0 too. so, we can multiply by 1 / x without reversing the sign of our inequality : ( 1 / x ) * ( x ^ 2 + 1 ) > = ( 1 / x ) * ( 2x ) x + 1 / x > = 2 this proves that the sum of x > 0 and its reciprocal 1 / x adds up to at least 2. i hope this helped! let us know if you have any more questions. - doctor luis, the math forum http : / / mathforum. org / dr. math / search the dr. math library : ask dr. mathtm © 1994 - 2013 the math forum


work continues on readying curiosity for surface operations on mars, with characterisation phase well underway. the week has seen the rover ’ s chemistry and camera system – chemcam – undergoing its calibration tests using a target system located towards the back of the rover, while scientists have been looking for candidates for the first full test firing of the system at a suitable surface target. chemcam is a complex system split between curiosity ’ s mast and body. the mast unit is the large box - like unit at the top of the mast. it contains a laser unit, a remote micro - imager ( rmi ) and a telescope for focusing both. the body unit carries three spectrographs for chemical analysis and has its own power supply and an electronic interface to the rover ’ s central computer system. chemcam has two main functions, split between the laser system ( the laser - induced breakdown spectroscopy ( libs ), to give it its proper name ) and the remote micro - imager ( rmi ). libs is designed to fire series of laser pulses at a target spot smaller than 1 millimetre on the surface of rocks and soils, vaporizing it. light from the resultant plasma is captured by the telescope and sent via fibre - optics to the on - board spectrographs for analysis, which should provide information in unprecedented detail about minerals and micro structures in martian rocks. additionally, the laser can be used to remove dust from the surfaces of rocks, allowing the drill on curiosity ’ s hand to obtain samples of the rock free from surface contaminants. the rmi provides black - and - white images at 1024×1024 resolution in a 0. 02 radian ( 1. 1 degree ) field of view – approximately equivalent to a 1500mm lens on a 35mm camera. rmi has two functions. in the first, it will be used in conjunction with libs to identify suitable targets and target locations ( targets can be selected autonomously or via earth - based selection and command ). working independently of libs, it will be used to obtain close - up images in support of robot arm - mounted experiments or provide images of very distant objects. this week, chemcam was calibrated using a target system mounted on the rear section of the rover, mounted below the uhf antenna. as a result of this, chemcam was confirmed ready for operations, and is expected to make it first test - firing on an actual martian rock sample on saturday august 18th. the sample is provisionally designated


examples of patterns of dyslexia in four different people. ‘ you don ’ t hear what is said, you hear something else ’. this pattern causes sounds to be distorted in the ear.. a pattern contains sounds and noises and the way in which they are perceived. this causes sounds and noises to be perceived in a distorted way.. you can ’ t read.. not being able to distinguish letters, he perceives a group of letters as one block. he can ’ t clearly perceive the outlines of a separate letter. for example, the difference between ‘ m ’ and ‘ n ’, ‘ b ’ and ‘ p ’, ‘ o ’ and ‘ a ’ is difficult to see.. if he wants to read a letter, it ’ s as if there is a barrier on his forehead, so that the information can ’ t get through to the brain. the process of taking in information stops at the forehead.. ‘ you can ’ t see letters ’. this activates a pattern in connection with the functioning of the brain whereby the letter he thinks he is reading is retrieved from the brain. this letter is stored as chemical data. this reacts with substances so that the letter is distorted. the information retrieved becomes something unfamiliar and creates an additional confusion, so that a totally different letter is read or written. when this happens for various subsequent letters, we get bizarre words.. he doesn ’ t see the space between the words. consequently he will link up the words. he loses words, he simple doesn ’ t see them. for example, he sees the first and the third word from a series of three words. he doesn ’ t see the second. this pattern isn ’ t in the form of a concept, like for example ‘ you don ’ t see spaces between words ’, nor in the form of an image. however, when i sense the pattern, i do know the meaning of the contents.. an inclination to make two letters into one whole, for example ‘ kk ’ in ‘ bookkeeper ’ becomes ‘ k ’, ‘ nn ’ in ‘ nanny ’ becomes ‘ n ’.. you can ’ t write letters.. ‘ you can ’ t write ’. this activates another pattern : the letters are not visible, the eyes don ’ t see how the letters are written. there is a signal from the brain that influences the movement of the hand during writing, so that a wrong letter is written.. you may not see letters ( the letters can be vaguely perceived ).. the


t see how the letters are written. there is a signal from the brain that influences the movement of the hand during writing, so that a wrong letter is written.. you may not see letters ( the letters can be vaguely perceived ).. the letters belong together ; everything is one block, there is no separation.. you may not see a word. a word can only be perceived vaguely or isn ’ t visible, not seeing a word that is there, skipping it.. when seeing a letter or a word, a signal is sent to the brain so that the eyes are influenced and perceive vaguely or perceive something else.. ‘ you make mistakes, you can ’ t write without mistakes, there are always mistakes ’. this activates a pattern regarding the functioning of the brain that causes retrieved data from the brain to react with the substance, so that the data is distorted and a mistake is written.. ‘ insecurity when reading or writing. a doubt crops up when reading or writing. not being sure of the letters or the words. no longer knowing how something is written ’. this activates a pattern regarding the functioning of the brain that causes the brain functions to stop when retrieving data, so that no information can be retrieved from the brain, so that he can ’ t know.. the letters dance, the eyes don ’ t see. this activates a pattern that causes a signal to be sent to the brain, so that the eyes don ’ t perceive perfectly.. a mistake occurs during the conversion of a letter into chemical data in the brain. distorted data are stored in the brain when learning about letters and words and the structure of language.. ‘ you can ’ t remember words, you can ’ t remember spelling ’. this causes information to be lost in the brain.. ‘ you can ’ t form words ’. this causes an absence of feeling for language and it prevents an automatism from coming after the rules concerning the construction of words have been learnt for some time.. you can ’ t distinguish letters ( in a word ), you see one whole.. everything is one block.. not being able to see a sharp outline. not being able to perceive a letter in a clearly defined way, perceiving vaguely.. the eyes don ’ t see, the eyes can ’ t distinguish.. you can ’ t read, you can ’ t see, you can ’ t write.. you can ’ t read, you don ’ t see the letters, it happens in a stumbling


’ t see, the eyes can ’ t distinguish.. you can ’ t read, you can ’ t see, you can ’ t write.. you can ’ t read, you don ’ t see the letters, it happens in a stumbling way. you skip parts, you don ’ t see the words.. the letters stand close together, you can ’ t see the difference between them.. not being able to see a word, not being able to see a text. when she sees a text, then she doesn ’ t see some words and she sees other words instead of the ones that are there. the text is formed in the brain, the signal picked up by the eyes is formed in the brain, so that she sees something else.. you may not be able to read, you have to be stupid, you may not read.. when she has read a sentence, then she immediately forgets it, and she rereads the sentence.. not being able to distinguish words ( or a sequence of letters ), like for example, the word ‘ block ’ is seen by her as ‘ bolck ’.. not wanting to make an effort when the level of reading becomes more difficult ( for example, she skips difficult words ).. ‘ you can ’ t remember ’. this prevents her from knowing the words she reads and then she just reads something at random.. the brain can ’ t follow anymore. when a text is read, a signal is given to the brain as a result of which the brain functioning is briefly interrupted.. when processing information in connection with language, a wrong chemical process in the brain starts so that data are converted into chemical compounds in a wrong way.. misinterpreting a letter. when seeing a letter, a signal is sent to the brain, as a result of which the formula of the chemical encoding of the letter is changed, so that another letter is perceived.. the brain processes for converting data into chemicals are functioning randomly and don ’ t follow a fixed formula, so that mistakes occur.. not being able to remember a word. she keeps the word in mind and when she starts to write, she has forgotten the word.. you can ’ t write, you can ’ t form letters. this activates a pattern that blocks the motor system of the hands so that she starts to write slowly and consequently loses words, because the writing can ’ t keep up with the thinking.. there is a space of time between hearing and writing. in


this activates a pattern that blocks the motor system of the hands so that she starts to write slowly and consequently loses words, because the writing can ’ t keep up with the thinking.. there is a space of time between hearing and writing. in this space of time, the sound is changed in the brain, so that she writes something else or some letters aren ’ t heard correctly, hence writing wrong.. you don ’ t know how you write something, therefore you just write something. you don ’ t think, you can ’ t think. you act on impulse, you just write something at random.. when she reads something, there is a signal from the brain to the eyes, so that the view is interrupted for a moment, and she perceives another letter than the one that is there. the eyes perceive a letter in a distorted way.. hastily, quickly, quickly. thinking too little before she writes something down, writing something at random as a result of which there are mistakes.. you can ’ t learn a language, you can ’ t master a language.. you may not know letters, you may not be able to write.. you don ’ t have an insight in a language, you can ’ t remember spelling rules.. not being able to think when writing. the brain processes that normally occur when reasoning about language, stop.. ‘ you may not write ’ combined with a signal to the brain as a result of which the processes for retrieving data are temporarily interrupted.. when she sees or has to write a letter, then a signal is sent to a wrong location in the brain ( where another letter is stored ) so that wrong data is retrieved.. not being able to remember words, not being able to remember the sequence of words. a wrong formula of how letters are interconnected is stored in the brain ( according to the rules of a language ).. not being able to assess words correctly. misunderstanding words, turning words around, hearing different words.. words in the sentences get lost. words that don ’ t succeed are linked together so that a word in between is omitted.. you can ’ t understand the words ( i. e. difficult words ).. not being able to understand special sounds ( əɪ, ʊ, ɑʊ, … ) sχ, χ, … or hear them correctly and therefore turning them into another sound or another spelling, namely writing them as you hear them.. when a sound is heard, then it is looked up in the brain,


ɑʊ, … ) sχ, χ, … or hear them correctly and therefore turning them into another sound or another spelling, namely writing them as you hear them.. when a sound is heard, then it is looked up in the brain, but when it isn ’ t found, another sound is used.. not knowing what to do with long words. not being able to overlook the whole and therefore splitting up compulsively. not being able to understand a long word, not being able to understand too many letters linked together. hence, a word has to be split up.. when she sees or hears a word : doubting the meaning, not being able to place it immediately, and not being able to write it as a result.. not knowing how she has to write something, not being able to remember how she has to write something. this activates a pattern in connection with the functioning of the brain : the brain functions are interrupted briefly when retrieving data, as a result of which the information retrieved gets lost once more ( she has forgotten once again ) and hence she writes something different. or there is a mistake when addressing the location of a word and another word is retrieved from the brain.. ‘ you can ’ t remember ’, activates a pattern in connection with the functioning of the brain that prevents letters, words and spelling rules from being stored in the brain. the brain processes are briefly interrupted so that the information doesn ’ t get lost.. data are normally converted into chemical information and these chemical compounds react with other chemicals and the end product is stored in the brain. a pattern causes the data to be converted into a wrong chemical form and hence these substances react with wrong chemical compounds for storage so that they are stored at a wrong location. when a word has to be remembered once again, then the word can ’ t be found anymore because it is stored at a wrong location. therefore words aren ’ t recognized when reading and she doesn ’ t know how to write words either, because she doesn ’ t remember. it ’ s as if it ’ s a new word and then she just writes something at random.. the letters are linked together. there is no distinction between two or more letters. the letters are perceived as one block. the letters aren ’ t perceived separately.. you can ’ t see.. the letters dance.. a pattern clouds the eyes : the eyes can ’ t perceive some letters sharply. there is a signal in the brain that causes the electrical signaling to the eyes by


’ t perceived separately.. you can ’ t see.. the letters dance.. a pattern clouds the eyes : the eyes can ’ t perceive some letters sharply. there is a signal in the brain that causes the electrical signaling to the eyes by the nervous system to pass in thrusts, so that the letters are otherwise perceived differently, since the eyes don ’ t perceive continuously, but with very small pauses. hence it ’ s difficult to distinguish letters that look alike.. there is a catch in the eyes when writing ( the transmission once again happens in thrusts, with interruptions ) and in the motor system : the muscles of the hand are blocked and contorted, hence writing slowly and with difficulty due to an altered functioning of the brain.. when writing, he can no longer see the letters that have already been written correctly due to the catch in the eyes. the letters that have already been written, become one block, so that he can ’ t trust this to write the next letters. he can ’ t perceive clearly what he has already written.. the knowledge of the form of the letters comes through from the brain too slowly : the brain slows down during the process of retrieving information from the brain, so that he writes more slowly.. yet another memory blockage : the letters don ’ t emerge from the brain during writing. hence doubting very much about the right letters.. a pattern makes him lose parts of what is dictated : he doesn ’ t hear some parts. he thinks he has already written parts that are not there yet. he hears things that aren ’ t there, so that he writes things that aren ’ t dictated ( this information is stored in the form of image in the pattern, not in concept form ).. you have to write mistakes.. ‘ it ’ s not like this, it ’ s different ’. this makes him doubt about the spelling of a letter when writing.. he has to deform the letters, he has to write another letter than the one it has to be ( pattern in the form of an image ).. he can ’ t see the whole ( pattern in the form of an image ).. he can ’ t remember. he can ’ t remember the spelling of a word. he can ’ t remember the rules of spelling. it confuses him. he can ’ t think logically with regard to the rules of a language. hence he writes things as he hears them.. when he has to remember or apply the rules, there is


t remember the rules of spelling. it confuses him. he can ’ t think logically with regard to the rules of a language. hence he writes things as he hears them.. when he has to remember or apply the rules, there is a very unpleasant feeling in his head and his thinking blocks. he simply writes what he hears in order to escape this.. ‘ you can ’ t write ’ activates a pattern that blocks the brain when reasoning when he writes. the brain processes that normally take place when reasoning ( retrieving and comparing data very quickly ), are blocked. person 4 : patterns of dyslexia combined with poor language abilities.. letters belong together, letters are one whole. an image of letters that flow into one another. ( this pattern will cause letters to flow into each other when looking at it, so that it ’ s difficult to perceive the separate letters of a word ).. a pattern with an image of a horizontal beam. this beam has to represent a collection of letters ( a word ), but the individual letters can ’ t be distinguished.. ‘ you can ’ t see ’. it ’ s fixed in the pattern that it ’ s about letters that have become faint. the outlining of a letter has become faint as a result, so that the form of a letter is difficult to distinguish.. the letters dance, you can ’ t see the letters.. ‘ you don ’ t write ’ and the joint of the wrist going tense, so that it ’ s difficult to form letters.. ‘ you can ’ t understand ’. it ’ s about writing, the writing of a language. ‘ you can ’ t understand how the letters belong together ’.. a pattern with the formula of a chemical. this chemical has to do with the storage of letters in the brain. there is another variation of the chemical according to the kind of letter, so that it is stored at another address in the brain according to the kind of letter. the variant of the chemical isn ’ t present for some letters, so that some letters are understood with great difficulty.. an image of a sentence that consists of separate parts ( words ). there is confusion about the words and how they belong together. hence, he will split up the words the wrong way or link them the wrong way, or add or omit words.. the letters of a words are not clearly visible, hence letters at the end and in the middle of a word are omitted or added, it is difficult to perceive whether


wrong way or link them the wrong way, or add or omit words.. the letters of a words are not clearly visible, hence letters at the end and in the middle of a word are omitted or added, it is difficult to perceive whether there is an ‘ i ’, ‘ ɪ ’ of ‘ ɛ ’, or, for example, he doesn ’ t see whether there is a single or a double ‘ n ’ or ‘ d ’ or whatever, and whether there is an ‘ e ’ or ‘ a ’ or whatever at the end of the word.. there is confusion about difficult combinations of letters. he can ’ t understand this, like for example, the sound ‘ χt ’. so, he ’ ll write a sound he doesn ’ t understand in the way he hears it. for example, he can ’ t understand the sound ‘ əɪ ’, and he ’ ll write something else.. there is confusion about difficult combinations of parts of words. he has difficulty distinguishing between the separate parts, like for example ‘ responsible ’. so, he ’ ll write : ‘ resonsile ’.. ‘ you can ’ t learn a language ’. knowledge with regard to language is very poorly stored in the brain. hence when having to remember language ( when reading and writing ), the knowledge isn ’ t an automatism and he has to think hard how to read and write time and again.. when he sees or hears a word ( for example in a dictation ), it ’ s not immediately clear how he has to read or write this word. he has to analyze the word letter by letter, he has to think about it. little or no knowledge of words and combinations of letters is stored in his brain ( and in the energies around him ). he has to analyze a word letter by letter time and again.. you can ’ t understand the rules of a language. hence writing something at random.. you can ’ t learn a language, you don ’ t know how to write. together with this, there is a feeling of confusion.. in the same way he doesn ’ t see all the parts of a word, he doesn ’ t hear all parts of a word either. for example, he doesn ’ t see the ending, therefore he will write the word wrong.. he can in fact understand the rules about the endings of verbs in dutch ( the dt - rule ), but he has difficulty applying it because he has difficulty perceiving whether a ‘ d ’ or a


according to the international continence society, overactive bladder is a symptom - defined condition characterized by urinary urgency, with or without urgency incontinence, usually with urinary frequency and nocturia ( night - time urination ). the term overactive bladder is appropriate if there is no proven urinary tract infection or other obvious pathology. overactive bladder was identified in 6. 5 % of finnish men and 9. 3 % of women. in younger age groups the condition was more common among women, but among those over 60 years old it was more common among men. urinary frequency and nocturia were generally more common than usual among those with an overactive bladder. however, most reported urinary frequency and nocturia was not overactive bladder. the research is based on a questionnaire conducted 2003 - 2004 among 3, 000 finnish women and 3, 000 finnish men. their ages ranged from 18 to 79. the subjects were taken from the population register. professor teuvo tammela and professor anssi auvinen are in charge of the research group, whose members are from the university of tampere, tampere university hospital, helsinki university central hospital and the south karelian central hospital in lappeenranta.


this comment has been deleted images courtesy peter vrsansky, slovak academy of sciences published august 30, 2012 a glowing green cockroach would seem much easier to kill than our more familiar kitchen pests, but this particular insect evolved its own set of lights to avoid exactly such predatory attention, according to a new study. luchihormetica luckae glows to mimic the bioluminescent click beetle, whose glow warns predators of its toxicity. for one thing, while many life - forms have evolved their own flashiness, most are found in the deep - sea — making bioluminescence a relatively rare trait on land. but l. luckae is particularly rare, in that it glows to mimic another insect. other uses of bioluminescence in the insect world, as in the case of the common firefly, are more attuned to attracting mates — lighting up to find love in the dark simply saves time. unfortunately, it also makes one much more visible to predators. " bioluminescence is like any evolutionary tool — there is no single use for it. it can attract, deter, or even be used as an invisibility cloak of sorts, " said olivia judson, an evolutionary biologist and author of dr. tatiana ' s sex advice to all creation. land animals glowed later than thought? the scientists studied an l. luckae cockroach collected in 1939 and housed at the national museum of natural history in washington, d. c. the team employed new technology to scan and analyze the biological mechanism responsible for the luminescence. they determined that the wavelengths of light released from both the click beetle and l. luckae — though developed via distinct evolutionary processes — are precisely the same. the new research may also provide evidence for a much later evolution of land - based bioluminescence, according to the study authors. that ' s because click beetles evolved their predator - deterring glow only 65 million years ago — recently compared with the 400 - million - year - old development of underwater bioluminescence. ( see a prehistoric time line. ) glowing roach a flash in the pan? l. luckae could prove to be a flash in the evolutionary - science pan. the one specimen analyzed in the study had been collected from a very specific region recently decimated by volcanic eruption. scientists now consider the creature so rare that collecting further specimens could cause its extinction. so chances are you won ' t be finding these little glowing pests raiding your cabinets. the glowing - cockroach study


what is freedom? i did not understand president bush ’ s inauguration speech. he used the word “ freedom ” twenty - seven times, but what freedom means to him was not clear. words can mean different things to different people and freedom is an example of that. to some people freedom means no responsibility. to others it means having power and ability to assume responsibility. is it freedom to be taken care of, or does freedom mean to be able to take care of oneself? is a baby free before it is born when it has no responsibility for its own physical needs, or is it free when it has been released from the confinement of the womb and must begin to do for itself? does freedom mean we are free to use the bible as a guide to our behavior? or does it mean freedom from god? " freedom " is a good word, but it cannot stand alone. it needs an implied or stated explanation and that was not evident in president bush ’ s speech. when a prisoner is allowed to leave his place of confinement, he gains his freedom from jail. those who knew that he was imprisoned would understand his new situation if they were told he gained his freedom, because jail is implied. a recently divorced man or woman might say, " i ' m free! ", but only those who knew the situation would understand that they meant free of the obligations of marriage. on the last day of school in spring the children shout that they are free. they mean they are free from the necessity of going to school. they are free to play and have fun. if a merchant gives you a gift with no strings attached you might say it was free of cost or obligation. if you no longer hurt, you have freedom from pain. when our country was born its first citizens said they were free. they meant their country was free from the political domination of england. people use the words, " free " and “ freedom ” to mean many things. “ free ” is even heard at funerals, especially when a person has suffered in his lifetime : " at last he is free! " in this case " free " means freedom from pain and suffering, but it also means dead. what about freedom from want and fear? couldn ’ t that mean the same thing as freedom from pain and suffering? couldn ’ t it also mean dead? what about being free to have an abortion? that certainly does mean freedom to make someone dead. in the western world we often speak of personal freedom, but here, too, the meaning is vague. the idea of