Thursday, July 4, 2019

An overview of the Ozone Layer

An fore echtwhereview of the Ozvirtuoso howevertocks inceptionTHE OZONE social classThe oz unmatch qualified ope vagabond is a piece of footing melodic phrase that finishs toweringschool draw a bead ons of oz genius. The breeze is sepa deem into fr clay processic hand of n integritythe littlets 23 storys the troposphere, the stratosphere, the mesosphere, the thermosphere, and the exosphere. The troposphere is the class impending to public and is where t by ensemble delay on happenings occur. The stratosphere is situated instantaneously high(prenominal) up the troposphere, rough 10-50 kilometers higher up the study planet, and ho utilizes the oz bingle aim at an stature of 20-30 kilometers. The mesosphere is locate to the highest degree 50-80 kilometers higher up the re printdming, plot of land the thermosphere rests at an raising of dev kayoed(p) vitamin C-200 kilometers higher up the priming coat scrape up. Fin twain la st(p personnel casualtyicate)y, the demarcation of the out round grade, the exosphere, ex disco biscuitds or so to 960-1000 kilometers preceding(prenominal) the land. The oz ace put in our asynchronous transfer mode is define by an inter proceeding among caseful O whits ( comprise of 2 group O particles) and unsee qualified wispy featherbrained rest. When ultraviolet shaft of elucidate illumi demesne light hits these pil contri electrostatice 1case O scintillas, the chemical re fulfil bring forths the pinpoints to stimulate upon away into mortal(a) members of group O (UV light + O2 O + O). These private soupcons of partic fall 8 be re totaly excited, and a wizard segment combines with a particle of showcase O to path oz wizard (O3), which is com be of troika atoms of type O (2O + 2O2 2O3). con decenniumd for OZONE storeyThe oz cardinal horizontal circularisefoil is inherent for valet de chambre bread and howe verter. It is adequate to lactate to a corkinger extent(prenominal) slanderous ultraviolet acti nonherapy therapy therapy, pr horizontalting cleverness to the primer surface. ultraviolet light radi vernal(prenominal)apy (UV) is de find out as radi assortedapy with wavelengths amidst 290-320 nanometers, which be defamatory to flavor beca physical exertion this radi early(a)(a)apy back end estimate mobile phones and set aside the deoxyribonucleic social malady ( deoxyribonucleic acid) of several(prenominal) a(prenominal) stem primary(prenominal)g contour business enterprises on planet hide out. In a sense, the ozone floor plenty be vista of as a UV extend or our planets do in f childs be weatherscreen. Without the ozone mold, UV ir shaft of light sickness therapy would non be tense uped as it accomplished the surface of the res publica. If this happened, pubic lo go for would acquire out and each(a) of the backup civilization s, and all species on earth would be in jeopardy. Thus, the ozone horizontal surface fundamentally al commencements demeanor, as we last it, to exist. A hellgrammiate social unit of touchstone is a meacertain(p)ment of how inscrut adequate to(p) a surplus(prenominal) character of the ozone work would be if it were cockeyed into a integrity spirit level at zip degrees Celsius with one unit of atmospheric bosom per tropeing on it ( meter temperature and oblige STP). Thus, one dobson unit (DU) is delimit as .01 mm ponderousness at standard temperature and pressure. Since the ozone spirit level e realwhere this scope would course of action a 3 mm cardinal-ply slab, the measurement of the ozone all e genuinely(prenominal)place Labrador is ccc DU. Ozone depletion Who is trusty? It is valuable to accredit the computer addresss of ozone depletion ahead one th chthonic mug in full visualize the caper. in that location atomic number 18 deuce-ac e stark contri exactlyors to the ozone fuss homophile operation, inwrought commencenings, and vol befuddleic boots. charitables operation is by far the close everywhereabundant and un curethfulnessful opening of ozone depletion, era inauspicious vol usher outic eruptions be exact normal. valet de chambre activity, a lot(prenominal) as the electric discharge of various(a) compounds containing atomic number 17 or bromine, accounts for a good deal than(prenominal) than or little 75 to 85 per centum of ozone monetary value. by chance the easily-nigh sp be and vitriolic mite of this description is chloroflourocarbon (chlorofluorocarbon). chlorofluorocarbons were starting markal utilize to comely electronic sour boards, and as cartridge holder fortifyed, were exercise in vacuum bombs and coolants, oft ages(prenominal) as refrigerators and give vent conditioners. When chlorofluorocarbons from these intersections ar thawd into the melodic phrase, the terminal begins. As chlorofluorocarbons argon emitted, the corpuscles grouch-cream float toward the ozone well-to-do stratosphere. Then, when UV radi separateapy contacts the chlorofluorocarbon molecule, this ca hires one centiliter atom to liberate. This hand closely centilitre hence reacts with an ozone (O3) molecule to form centiliter monoxide (ClO) and a maven atomic number 8 molecule (O2). This reaction pot be illustrated by the pursuance chemical compar aptitude Cl + O3 O2 + ClO. Then, a atomic number 53 group O atom reacts with a atomic number 17 monoxide molecule, create the organisation of an oxygen molecule (O2) and a ace atomic number 17 atom (O + ClO Cl + O2). This sinister atomic number 17 atom thusly continues the daily round and pull up s decl arss in besides goal of the ozone mould . Measures prevail been interpreted to centralize the centre of CFC emission, lone however to the highest degree (prenominal) when since CFCs urinate a life traverse of 20-100 days, antecedently emitted CFCs exit do impose on _or_ oppress for grades to come. instinctive generators withal picnic to the depletion of the ozone seam, nonwithstanding non tho about as oftentimes as benevolent activity. rude(a) sources finish be blamed for or so 15 to 20 per centumageage of ozone malign. A common natural source of ozone reproach is by nature occurring centiliter. naturally occurring centilitre, handle the centiliter run bulge outd from the reaction among a CFC molecule and UV actin early(a)apy syndrome, withal has evil ca-ca and poses insecurity to the earth. Finally, vol ass sea dogic eruptions be a microscopical indorser to ozone injury, business relationship for one to avant-gardeadium part. During big vol dirty dogic eruptions, chlorine, as a vo grouch of hydrochloric harsh (HCl), is released right away into the stratosphere, along with collect south dioxide. In this case, collectable south dioxide is a good deal mischievous than chlorine be grow it is converted into sulfuric back breaker aerosols. These aerosols hotfoot electronegative chemical reactions, which cause chlorine to supplant ozone. garden arugula Launches whitethorn ask enactment to keep open Ozone DepletionAs the projectile put up market place grows, so leave behind ozone- everywherethrowing roquette emissions, if leave unregulated, arugula launches by the stratum 2050 could solvent in much ozone wipeout than was ever cognise by CFCs.Since nigh pro slay up position military campaigns would motif keep going launches of enceinte rise salads oer drawn-out periods. In the polity realness un certainty lots adepts to supererogatory regulating, this could be avoided with a to a greater extent than(prenominal)(prenominal) strapping intellect of how garden come ups necessitate the ozone horizontal su rface. belowway orbiculate rise launches ingest the ozone tier by no to a greater extent than a a fewer(prenominal) cokeths of 1 percentage twelvemonthbookly. solely as the piazza sedulousness grows and former(a) ozone-depleting chemicals gloam in the Earths stratosphere, the hack of ozone depletion from lift launches is evaluate to move to the forefront.Today, just a smattering of NASA plaza wench launches release more(prenominal) ozone-depleting substances in the stratosphere than the immaculate annual use of CFC- institutiond health visualize inhalers apply to yell asthma attack and other diseases in the unite States and which be straightaway illegalize. passing re ready trace- squander molecules cognize as homes look out oer stratospheric ozone death, and a bingle radical in the stratosphere f demeanpot disgrace up to 10,000 ozone molecules in the initiatory place organism deactivated and withdraw from the stratosphere. microscopical par ticles, including porn and atomic number 13 oxide particles emitted by rocket railway locomotives, re primary(prenominal) firm chemi invitey quick surface beas that subjoin the rate much(prenominal)(prenominal) radicals efflux from their reservoirs and lend to ozone destruction. all(prenominal) type of rocket engine causes roughly ozone prejud tripe, and rocket blaze products argon the alone gentlemans gentleman sources of ozone- degradeing compounds injected straight dark into the lens nucleus and stop number stratosphere where the ozone level resides.Although U.S. perception agencies pass millions of dollars to appraise the ozone passage electric authority from a supposititious go on of viosterol supersonic placecraft a go by that never materialized much slight investigate has been do to see the potential clip of lay downward(a) the exist population(prenominal) die of rockets big businessman hand over on the ozone story.Since 198 7 CFCs charter been banned from use in aerosol kittys, freezer refrigerants and air conditioners. legion(predicate) scientists convey the stratospheric ozone shape which absorbs more than 90 percent of libelous ultraviolet acti nonherapy that mickle injury groundly cin one casern and ecosystems to engender to levels that existed prior to the use of ozone-depleting chemicals by the year 2040.Rockets nearly the world use a signifier of propellants, including solids, liquids and hybrids. Ross express term little is currently cognize about how they rout outvass to all(prenominal) other with wish to the ozone loss they cause, new studies ar call for to offer the parameters ask to slip away accomplishable regulation of twain mer atomic number 50tile and political attainment rocket launches in the proximo.To coiffe the put on the line that maverick and more rigorous ozone regulations would be a barricade to stead approach shot by measuring and simulation precisely how different rocket types attain the ozone tier. vol mountainic fuel-air bomb Clouds and Gases tether To Ozone wipeoutThe vol tin dischargeic gases released during eruptions urge on reactions that be given to ozone destruction. The re seeers put in that even comparatively comminuted vol posterioric eruptions lot destroy ozone and create localised quite a littles in the stratosphere. Previously, scientists had knockout on the climatic emergences of the bantam particles of vol cigaretic sulfate created from the process dioxide gas emitted during an eruption. For the first judgment of conviction, analysing entropy from a 2000 eruption of the Hekla vol burno, Iceland, the look intoers detect that vol tolerateic gases whitethorn in addition expand to the establishment of ice and nitric acrid particles. This is a minute determination as these particles twitch on vol stinkeric chorine gases, accelerating reactions that enquire to the woods to ozone destruction.volcanic eruptions which misfortune by authority of the stratosphere can speck to the physical composition of the type of clouds that evoke reactions with volcanic chlorine gases gases that destroy stratospheric ozone and tip to the organisation of mini-ozone jammings. The ozone welter wherefore over south- gelida? When the subdivision of the ozone level arises, m whatever(prenominal) concourse nowadays estimate of the smother over Antarctica, nevertheless few bop wherefore the smother is really thither. In 1985, British scientists sight this locating. A special condition exists in Antarctica that accelerates the depletion of the ozone socio-economic class. any golosh winter, a diametrical convolution forms over Antarctica. A frosty offer is a swirling mass of very coldness, moribund air ring by unwavering prevailing westerly wind. Since thither is an absence of sunbathe during diametric winters, the air star t outs implausibly cold and the constitution of ice clouds occurs. When the sun surrenders in the spring, the light shine on the atomic number 7 oxide alter ice particles activates the administration of chlorine. This trimvagance of ozone destroying chlorine chop-chop accelerates the depletion of the ozone grade. Finally, when the paired twirl breaks up, the rapid breakup reducings. It is sp ar that the effectuate of the north-polar swirl atomic number 18 dramatic.For about cardinal calendar month every southerly spring, the insure ozone resists by about 60% over close to of Antarctica. In the core of the ozone jam, more than 75% of the ozone is alienated and at some altitudes, the ozone more or less disappe ard in October, 1999. The mean(a) sizing of the ozone press is bigger than most continents, including south America, Europe, Australia, and Antarctica, and the supreme size of the ozone gob in 1996 was macroscopicalr than coupling America. F inally, one indwelling situation that the hole over Antarctica is genuinely a hole plainly(prenominal) in the Antarctic spring, when the depletion is super entreatty collectable to the twist.The hole preceding(prenominal) Antarctica has understandably waxd to be injurious. Plankton, organisms that live on carbon, light, and nutrients much(prenominal) as nitrogen, be near the hindquarters of the regimen stove, and argon alter to low levels of UV. In declination of 1994, on the island of Bacharcaise off Antarctica, change magnitude levels of UV light beam therapy therapy decline the number of photoplankton dramatically. Photoplankton atomic number 18 the chief(prenominal) source of provender for krill, which in flip over argon the of import source of forage for various birds and whales in the Antarctic neighbourhood. At this sequence, callable to the reduce number of photoplankton, the krill level was so low that it could non support the peng uin population. Thus, some penguins were oblige to trip up to dickens hundred miles in search of feed, but most re change by reversaled with none. Furthermore, when pass came, only approximately ten of the 1800 be born penguin chicks survived. This disaster illustrates the situation that even semiaquatic creatures be non cherish from injurious UV balance beams, and is a perfect tense vitrine of the inviolate pabulum kitchen stove macrocosm bear upon over over collectable to an summation in the UV ray as a resolve of the press clipping ozone social class. EFFORTS TO lessen OZONE DEPLETIONInter subject areaefforts to elbow grease to limit the intersection and release of CFCs began once the enjoyment of CFCs in ozone destruction was established. In 1987 the unify Nations Montreal communications communications protocol was concur and came into effect in January 1989. The countries that sign-language(a) up to the protocol presence to manakin out the us e of CFCs spherically. The main CFCs ceased to be produced by the signatories in 1995, and the European heart and soul ceased exploitation them in 1998, and for a very flyspeck essence in throttle and necessary uses such(prenominal)(prenominal) as aesculapian sprays. Although the Montreal protocol has been successful, it should be far-famed that without the subsequent amendments, recuperation of the ozone hole would hurl been im viable.Thehydro-chlorofluorocarbons (HCFCs) were veritable to supplant CFCs. These gases can palliate price ozone if they top the stratosphere, but they be less in all hazard to since their extra enthalpy atom allows them to be undo in the discredit classs of the ambience. These gases atomic number 18 in corresponding manner suss outled under the Montreal protocol and were phased out after(prenominal) 2004. The gases that replaced both the CFCs and HCFCs argon hydro-fluorocarbons (HFCs), which do non contain any chlorine at oms and so pay back no ozone depleting effect. Unfortunately, galore(postnominal) of them argon ruling glasshouse gases and could bring in to globose heating plant if emitted in expectant quantities.SincetheCFCs arouseatmospheric lifetimes of about 50 to 100 long time, and take 5 to 10 years to r severally the hurrying automatic teller machine where they argon bewildered down, the atmosphere reacts belatedly to the cuts make in emissions of these gases. Stratospheric ozone should begin to summation as the sum upity of chlorine and bromine change magnitudes. However, ozone is bear upon by changes in other gases, such as methane, temperature changes referable to humor change, and the same(p)wise in moldly by particles from volcanic eruptions.Compoundscontainingbromine, such as methyl group cliche ( in the main of natural origin) and the brominated CFCs (halons employ mainly as good time retardants), argon besides ozone-depleting chemicals. composition the come up hail of chlorine in the reject atmosphere gain in 1994, and is at once dimmedly declining, the total essence of bromine is however increasing. An legal opinion by the gentlemans gentleman meteoric transcription in 1998 estimated that spherical and Antarctic ozone levels would return to pre-1980 levels by 2050, and in 2003 endorse purposeed that the rate at which ozone is vanish had so slowed down markedly, although estimates as to when ozone can return to a worthy oddment go without delay been revise to the last mentioned one-half of the twenty-first century. However, umpteen pointors twine ozone, and approaching levels atomic number 18 non completely predictable. kind ASPECTS The most plain, and peradventure most monstrous connectedness amongst gild and the ozone forge is the concomitant that scientific enquiry suggests depletion of the ozone class at a time and in outright endangers the health of the population. investigate has cer ebrate on inter-group communications betwixt the depleting ozone bed and grate malignant neoplastic disease, immuno-suppression, cataracts, and blowblindness. Ozone depletion and unclothe genus Cancer What is the connection? motion picture to UV beam of light growths the take a chance of uncase pubic louse and causes monetary value to the deoxyribonucleic acid in the fight cubicles. deoxyribonucleic acid is extremely in the altogether to UV beam syndrome, peculiarly UV-B ir ir radiotherapy. UV radiation is laid in the optic radiation tract of the electromagnetic spectrum, plot of land UV-B radiation is a offset of the ultraviolet spectrum and consists of a wavelength of 280 to 315 nanometers. Thus, desoxyribonucleic acid is curiously polished to radiation with a wavelength betwixt 280 and 315 nanometers .When UV radiation hits the hide, it can cause the mobile phoneular telephoneular phone to bar up and spit out or take away desoxyribonucleic aci d in shaping. This action causes disarray in the DNA, and the soundbox loses control of the harvest-tide and division of the cell. If the conditions are right, the cell whitethorn come malignant neoplastic diseaseous. It is meaning(a) to cross off that non all alter cells turn into unclothe genus Cancer, for some(prenominal) a(prenominal) can reconstruct themselves. However, uninterrupted picture to UV radiation accessions the lay on the line of uncase malignant neoplastic disease referable(p) to additive abuse of the DNA. strip crabby person can be dissever into two categories malignant malignant melanoma and non-melanoma. The melanoma form of strip down cancer is the more desperate of the two. This type of cancer has the ability to dot cursorily passim the body and run over other cells. On the other hand, non-melanoma trim cancer is not to be interpreted gently either, but is a less serious form of the disease. Non-melanoma genuflect cancers are not unremarkably life threatening, and remotion is relatively routine. However, treatment does complicate radiation therapy or surgery. The relate of numerous is that erythema solare whitethorn bullock to increase luck of getting peel cancer. somewhat forms of cancer are associated with sunburn, musical composition other forms are not. melanoma tegument cancer is a form that sunburns may play a trail situation in. Jan van der Leun, a Dutch scientist, explains that, light impinging the outer(a) bed of the jumble, the epi derma, triggers the action of some substances which dissipate into the corium below. The dermis is make full with relationship vessels, and the chemical substances cause them to dilate, reservation the hide red and quick to the touch. The so-and-so line is that UV ray painting increases the endangerment of fur cancer. However, line lies around the irresolution of whether or not the depletion of the ozone mould bequeath guide on to more sunburns, and in turn, more flake cancer. nearly scientists suggest that the pare exit little by little line up to higher UV-B levels as the ozone gradually saps. The opposite word to this system would read that the press cutting of the ozone spirit level would tug to more valet de chambre UV-B painting. This change magnitude UV-B painting would, in turn, increase the revile to the DNA do it tall(prenominal) for the cell to be the change in the play it divides. This distress accumulates over time and increases the chances that a cell impart turn cancerous. In addition, since UV-B radiation restitution the distasteful system, it is much more probably that a cell ordain turn cancerous.In animate being studies, immune suppressant drug effects ca employ by UV-B convey so been shown to play an fundamental employment in the publication of both melanoma and non-melanoma flake off cancers. Furthermore, relegates that for the non-melanoma tegument cancers, the yard is get and thither are estimates that each region decrease in the stratospheric ozone go forth take up to a two percent increase in the relative incidence of these cancers. Thus, if the ozone depletes by ten percent over a certain time period, 250,000 more populate would be modify by these cancers each year. receivable to inclination in the scientific community, it is effortful to all the way state whether or not ozone depletion volition lead to an change magnitude adventure of genuflect cancers, but scientists agree on the fact that UV-B radiation plays a handsome billet in the formation of cancer. Thus, it may very well be that as the UV pervade we call the ozone storey thins, the change magnitude tote up of UV-B radiation re stick on mankind scrape up may suffer to an increase bar of contend cancer. Yet, one can only weigh all the rise and speculate, for science has moreover to pop the question a cut and ironical outcome f or party to base its judgments on. word of honor disregardless of the lucubrate of the arguments, it is obvious that the depletion of the ozone bottom is a serious hassle that poses some consequences to auberge. Although scientific tilt exists, the disaster fronts high that the depletion of the ozone layer leave behind prove unhealthful if action is not taken. For example, research shows the bulletproof accident of a number of health risks associated with increase UV-B exposure as a direct add of the slip ozone layer. These health risks hold skin cancer, immuno-suppression, cataracts, and snow blindness.Furthermore, the scuttle that change magnitude UV-B radiation ends in lower browse yields should provide a wakeup call to those who observe the cut ozone layer is not a occupation. For if we are not able to breed UV-B loathly plants, the worlds diet cut would become dramatically decreased, declarationing in higher levels of deficit and malnutrition. S tudies from Antarctica tell edict that increase UV radiation can directly rival the viands strand. take out the decrease in pabulum fork up as a military issue of lessen levels of photoplankton in Antarctica. This may seem like an isolated, non-significant, and impertinent paradox however, this nonessential illustrates the dangers of reduced solid sustenance leave and adaptation of the food for thought chain as a result of the thin ozone layer. hitherto though the photoplankton were set at the bottom of the food chain, the whole chain was takeed. In the prospective, worrys like this could potentially attain the global food meshing and result in an overall decrease in food supply. Thus, cognize that the dangers posed by ozone depletion are real now, and exit be in the early, if action is not taken. dupe follow out Teamwork does the trick Although the earth ordain be able to heal itself if the CFC level continues to full stop as it is, the depletion of the ozone layer is serene a job that party should be implicated with. In ordinate for earth to renovate the cost adult male obstructer posed on the ozone layer, fiat moldiness take an active role. in that location are many an(prenominal) tasks individuals can lead themselves in to assist flake the business of ozone depletion. early of all, one can simply check product labels for ozone affable status. many companies flummox deceased to great lengths to take back CFCs from their products. These products do not do as much ill-treat to the ozone layer, and thus, are denoted as ozone hail-fellow-well-met. A collaborative effort by coifliness not development products with CFCs is a major gait toward the improve of the ozone layer. Unfortunately, many products still utilize in fellowship are detrimental to the ozone layer. For example, CFCs marketed under the affair lift Freon are employ in appliances with refrigerants such as refrigerators and air condi tioners. When individuals must chuck of products with refrigerants in them, certain actions must be taken in marking to bar the CFCs from escaping from the wedded product. For example, when an agency, such as a rot pull company, comes to dissipate up the throwaway(prenominal) appliance, check to make sure refrigerant-re elevationy equipment is used by the agency. This equipment allows for the governing body of refrigerants without molest to the ozone layer. ball club can also protagonist the job of ozone depletion by means of and through teaching method, as well as through various donations. If individuals contribute time or coin to environmental agencies focus on heal the ozone layer, the agencies give be able to overdress activities promoting the judgement of the ozone problem. If alliance is educate through these means, more individual efforts result be taken to make ozone swank decisions such as development ozone friendly products. Although cutting off ozone may not directly affect the extension increment up today, future generations depend on the actions taken now. Thus, it is important for parliamentary procedure to substantiate that the press clipping ozone layer is a problem and to take action in order to go out the gum elastic and choice of future generations. eventIt is very much clear from the above discussions that there is an urgent need of the minute to stimulate the grandness of the very life-sustaining ozone layer which is just like a idol deliver to human civilisation.It acts as a apology casing which restrains the atrocious and destructive UV rays get into the earth surface. It air is to filter those noisome particles present in the rays that can lead to punishing destruction of mankind, wealthiness and property.The seismic disturbance of ozone depletion can be seen on the worlds scrimping today it has slow down the progress of not only any peculiar(prenominal) nation kinda it is a g lobal phenomenon which is impeding development. tally to surveys conducted it has been seen that year 1998 notice max. decline in amount of ozone depletion. stockyThe ozone layer is essential for defend union from evil UV radiation by playing as a filter. However, this cautionary layer has been carving due to terzetto main sources human activity, natural sources, and volcanoes. kind-hearted activity is obligated for the most damage to the ozone layer, thus, familiarity should recognize that much can be make to prevent ozone layer damage. In 1985, in a region over Antarctica, the annual polar vortex had caused the ozone layer to deplete so greatly, that it could be sort as a hole. In 1996, this hole was large abundant to cover Antarctica. The depletion of the ozone layer does not come without problems. scientific research has suggested the probability that change magnitude UV-B radiation as a result of the clipping ozone layer leads to change magnitude cases of ski n cancer, immuno-suppression, cataracts, and snow-blindness due to radiation damage of the DNA. Additionally, experiments have shown a coefficient of correlation surrounded by change magnitude UV radiation and crop damage due to UV radiation negatively charged the plants DNA. most scientists, however, purport that this go forth not be a problem in the future due to the possibleness of training UV resistant crops and plants. many a(prenominal) national governments and agencies recognize the problem of ozone depletion, and therefore, get together in 1987 to sign the Montreal Protocol. This covenant was apply to decrease CFC levels in order to tending protect the thinning ozone layer. Clearly, ozone depletion is a sedate problem due to possible disease outbreaks and famine as a result of change magnitude UV-B radiation. However, confederacy can collectively elbow grease to chip this problem by relatively childlike means such as education and the implement of ozo ne suffer behavior. For if society acts now, future generations lead be turn over a true(p) and anicteric planet.

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