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Iwebhusayithi ye-IEEE ibeka iikuki kwisixhobo sakho ukuze ikunike amava angcono omsebenzisi. Ngokusebenzisa iwebhusayithi yethu, uyavuma ukubekwa kwezi kuki. Ukuze ufunde okungakumbi, nceda ufunde uMgaqo-nkqubo wethu waBucala.

Iingcali eziphambili kwi-RF dosimetry zihlalutya intlungu ye-5G—kunye nomahluko phakathi kokuvezwa kunye nedosi

UKenneth R. Foster unamava eminyaka emininzi efunda ngemitha yerediyo (RF) kunye nemiphumo yayo kwiinkqubo zebhayoloji. Ngoku, ubhale uphando olutsha ngalo mba kunye nabanye abaphandi ababini, uMarvin Ziskin kunye noQuirino Balzano. Bebonke, bobathathu (bonke bangama-tenale IEEE fellows) banamava angaphezu kwenkulungwane ngalo mba.
Olu phando, olupapashwe kwi-International Journal of Environmental Research and Public Health ngoFebruwari, lujonge kwiminyaka engama-75 edlulileyo yophando malunga novavanyo lokuvezwa kwe-RF kunye ne-dosimetry. Kulo, ababhali abasebenzisana nabo bachaza indlela eli candelo elihambele phambili ngayo kunye nesizathu sokuba balibone njengebali lempumelelo yesayensi.
I-IEEE Spectrum ithethe nge-imeyile noprofesa weYunivesithi yasePennsylvania u-emeritus Foster. Besifuna ukufunda okungakumbi malunga nokuba kutheni izifundo zovavanyo lokuvezwa kwe-RF ziphumelela kangaka, yintoni eyenza i-RF dosimetry ibe nzima kangaka, kunye nokuba kutheni iinkxalabo zoluntu malunga nempilo kunye nemitha engenazingcingo zingabonakali ngathi ziyanyamalala.
Kwabo bangayaziyo le mahluko, yintoni umahluko phakathi kokuchatshazelwa yintsholongwane kunye nomthamo wayo?

UKenneth Foster: Kwimeko yokhuseleko lwe-RF, ukuvezwa kubhekisa kwintsimi engaphandle komzimba, kwaye idosi ibhekisa kumandla afunxwa ngaphakathi kwizicubu zomzimba. Zombini zibalulekile kwiindlela ezininzi zokusetyenziswa - umzekelo, uphando lwezonyango, lwempilo yomsebenzi, kunye nokhuseleko lwe-elektroniki lwabathengi.
"Ukuze ufumane uphononongo oluhle lophando malunga nemiphumo yebhayoloji ye-5G, jonga inqaku lika-[Ken] Karipidis, elifumene 'akukho bungqina buqinisekileyo bokuba amasimi e-RF asezantsi angaphezulu kwe-6 GHz, njengalawo asetyenziswa ziinethiwekhi ze-5G, ayingozi kwimpilo yabantu.'" -- Kenneth R. Foster, kwiYunivesithi yasePennsylvania
Foster: Ukulinganisa amasimi e-RF kwindawo ekhululekileyo akuyongxaki. Ingxaki yokwenyani ephakamayo kwezinye iimeko kukwahluka okuphezulu kokuchatshazelwa yi-RF. Umzekelo, uninzi lwezazinzulu luphanda amanqanaba e-RF kwindawo engqongileyo ukuze lujongane neengxaki zempilo yoluntu. Xa sicinga ngenani elikhulu lemithombo ye-RF kwindawo engqongileyo kunye nokubola ngokukhawuleza kwentsimi ye-RF kuyo nayiphi na indawo, oku akulula. Ukuchonga ngokuchanekileyo ukuchatshazelwa komntu ngamnye kumasimi e-RF ngumceli mngeni wokwenene, ubuncinane kwizazinzulu ezimbalwa ezizama ukwenza njalo.

Xa wena kunye nababhali bakho nibhala inqaku le-IJERPH, ngaba injongo yenu yayikukukhomba impumelelo kunye nemingeni ye-dosimetric yezifundo zovavanyo lokuvezwa? Foster: Injongo yethu kukukhomba inkqubela phambili emangalisayo eyenziwe luphando lovavanyo lokuvezwa kwiminyaka edlulileyo, nto leyo eyongeze ukucaca okukhulu kuphononongo lweziphumo zebhayoloji zamasimi erediyo kwaye iqhubele phambili kakhulu kubuchwepheshe bezonyango.
Ingakanani inkqubela phambili yezixhobo kwezi ndawo? Ungandixelela ukuba zeziphi izixhobo ezazikho kuwe ekuqaleni komsebenzi wakho, umzekelo, xa kuthelekiswa nezo zikhoyo namhlanje? Izixhobo eziphuculweyo zinegalelo njani kwimpumelelo yovavanyo lokuvezwa?
Foster: Izixhobo ezisetyenziselwa ukulinganisa amasimi e-RF kuphando lwezempilo nokhuseleko ziya zisiba ncinci kwaye zinamandla ngakumbi. Ngubani owayenokucinga kwiminyaka embalwa eyadlulayo ukuba izixhobo zorhwebo ziya kuba namandla ngokwaneleyo ukuba zisiwe emsebenzini, zikwazi ukulinganisa amasimi e-RF anamandla ngokwaneleyo ukubangela ingozi emsebenzini, kodwa zibe nobuthathaka ngokwaneleyo ukulinganisa amasimi abuthathaka kwii-antenna ezikude? Kwangaxeshanye, misela uluhlu oluchanekileyo lwesignali ukuze uchonge umthombo wayo?
Kwenzeka ntoni xa ubuchwepheshe obungenazingcingo butshintshela kwiibhendi ezintsha zefrikhwensi—umzekelo, amaza e-millimeter kunye ne-terahertz kwiselula, okanye i-6 GHz ye-Wi-Fi?
Foster: Kwakhona, ingxaki inxulumene nobunzima bemeko yokuvezwa, kungekhona izixhobo. Umzekelo, izikhululo zesiseko seeselula ze-5G eziphezulu zikhupha imisebe emininzi ehamba esibhakabhakeni. Oku kwenza kube nzima ukulinganisa ukuvezwa kwabantu abakufutshane neendawo zeeseli ukuqinisekisa ukuba ukuvezwa kukhuselekile (njengoko phantse rhoqo kunjalo).
“Mna ngokwam ndixhalabile kakhulu ngempembelelo enokubakho yexesha elininzi lokubukela isikrini kwimiba yophuhliso lomntwana kunye nobumfihlo.” – Kenneth R. Foster, kwiYunivesithi yasePennsylvania

Ukuba uvavanyo lokuvezwa luyingxaki esonjululweyo, yintoni eyenza ukuba ukutsiba kwi-dosimetry echanekileyo kube nzima kangaka? Yintoni eyenza eyokuqala ibe lula kakhulu kuneyokugqibela?
Foster: I-Dosimetry inzima kakhulu kunovavanyo lokuvezwa. Ngokuqhelekileyo awunakufaka i-RF probe emzimbeni womntu. Zininzi izizathu zokuba kutheni ungalufuna olu lwazi, njengakwiindlela zonyango lwe-hyperthermia kunyango lomhlaza, apho izicubu kufuneka zifudunyezwe ukuya kumanqanaba achazwe ngokuchanekileyo. Ubushushu buncinci kakhulu kwaye akukho nzuzo yonyango, buninzi kakhulu kwaye uya kusitshisa isigulana.
Ungandixelela okungakumbi ngendlela i-dosimetry eyenziwa ngayo namhlanje? Ukuba awukwazi ukufaka i-probe emzimbeni womntu, yeyiphi into elandelayo engcono?
Foster: Kulungile ukusebenzisa ii-RF meters zakudala ukulinganisa amasimi emoyeni ngeenjongo ezahlukeneyo. Oku kunjalo nangomsebenzi wokhuseleko emsebenzini, apho kufuneka ulinganise amasimi erediyo ayenzeka emizimbeni yabasebenzi. Kwi-hyperthermia yeklinikhi, usenokufuna ukuqokelela izigulane ngee-thermal probes, kodwa i-computational dosimetry iphucule kakhulu ukuchaneka kokulinganisa iidosi zobushushu kwaye ikhokelele ekuphuhliseni okubalulekileyo kwitekhnoloji. Kwiizifundo ze-RF biological effects (umzekelo, ukusebenzisa ii-antenna ezibekwe kwizilwanyana), kubalulekile ukwazi ukuba ingakanani i-RF energy efunxwayo emzimbeni kunye nokuba iya phi. Awunakuyishukumisa nje ifowuni yakho phambi kwesilwanyana njengomthombo wokuvezwa (kodwa abanye abaphandi bayakwenza oko). Kwiizifundo ezinkulu, ezifana nophando lwakutshanje lweNational Toxicology Program malunga nokuvezwa kwamandla e-RF ebomini bonke kwiimpuku, akukho ndlela yokwenyani endaweni ye-computed dosimetry.
Ucinga ukuba kutheni kukho iingxaki ezininzi eziqhubekayo malunga nemitha engenazingcingo kangangokuba abantu balinganisa amanqanaba emakhaya?

Foster: Ukuqonda umngcipheko yingxaki enzima. Iimpawu zemitha yerediyo zihlala zibangela inkxalabo. Awunakuyibona, akukho nxibelelwano luthe ngqo phakathi kokuchatshazelwa yimpembelelo eyahlukeneyo abanye abantu abayixhalabelayo, abantu badla ngokubhidanisa amandla erediyo (ukungazi-ionizing, oko kuthetha ukuba ii-photon zayo zibuthathaka kakhulu ukuba zingaphula iibhondi zeekhemikhali) kunye ne-X-reyi ezizi-ionizing, njl. Imitha (iyingozi kakhulu). Abanye bakholelwa ukuba "bavakalelwa kakhulu" kwimitha engenazingcingo, nangona izazinzulu zingakwazanga ukubonisa olu vakalelo kwizifundo ezingaboni kakuhle nezilawulwayo. Abanye abantu baziva besongelwa linani elixhaphakileyo lee-antenna ezisetyenziselwa unxibelelwano olungenazingcingo. Uncwadi lwezenzululwazi luqulethe iingxelo ezininzi ezinxulumene nempilo ezinomgangatho owahlukeneyo apho umntu anokufumana ibali eloyikisayo. Abanye izazinzulu bakholelwa ukuba kusenokwenzeka ukuba kukho ingxaki yezempilo (nangona i-arhente yezempilo ifumanise ukuba ayinaxhala kodwa yathi "uphando oluthe kratya" luyafuneka). Uluhlu luyaqhubeka.

Uvavanyo lokuvezwa ludlala indima koku. Abathengi banokuthenga ii-RF detectors ezingabizi kakhulu kodwa ezinobuthathaka kakhulu baze baphande imiqondiso ye-RF kwindawo abakuyo, apho zininzi khona. Ezinye zezi zixhobo "zicofa" njengoko zilinganisa ii-radio frequency pulses ezivela kwizixhobo ezifana neendawo zokufikelela ze-Wi-Fi, kwaye ziya kuvakala njengekhawuntara yeGeiger kwi-reactor yenyukliya yehlabathi. Kuyoyikisa. Ezinye ii-RF meter zithengiswa nokuzingela iziporho, kodwa olu lusetyenziso olwahlukileyo.
Kunyaka ophelileyo, iBritish Medical Journal yapapasha ubizo lokumisa ukusasazwa kwe-5G de kuqinisekiswe ukhuseleko lwetekhnoloji. Ucinga ntoni ngezi fowuni? Ngaba ucinga ukuba ziya kunceda ukwazisa iqela loluntu oluxhalabileyo malunga nemiphumo yempilo yokuvezwa yi-RF, okanye zibangele ukudideka okungakumbi? Umphathi: Ubhekisa kwingxelo yoluvo ebhalwe [yingcali yezifo uJohn] Frank, kwaye andivumelani nenkoliso yayo. Uninzi lwee-arhente zempilo eziphonononge isayensi zicele nje uphando oluthe kratya, kodwa ubuncinane enye - ibhodi yezempilo yaseDatshi - icele ukuba kumiswe ukuqaliswa kwe-5G ephezulu de kwenziwe uphando oluthe kratya lokhuseleko. Ezi ngcebiso ngokuqinisekileyo ziya kutsala ingqalelo yoluntu (nangona i-HCN ikwabona ngathi akunakwenzeka ukuba kukho naziphi na iingxaki zempilo).
Kwinqaku lakhe, uFrank ubhala athi, "Amandla avelayo ezifundo zelebhu abonisa [amasimi e-electromagnetic erediyo-frequency] iziphumo zebhayoloji ezitshabalalisayo ze-RF-EMF."

Yiyo loo ngxaki: kukho amawaka ezifundo ze-RF biological effects kwiincwadi. Amanqaku okugqibela, ukubaluleka kwimpilo, umgangatho wophando kunye namanqanaba okuvezwa ahluka kakhulu. Uninzi lwazo lubike uhlobo oluthile lwempembelelo, kuzo zonke iifrikhwensi kunye nawo onke amanqanaba okuvezwa. Nangona kunjalo, uninzi lwezifundo lwalusemngciphekweni omkhulu wokukhetha icala (ukungabikho kwedosimetry eyaneleyo, ukungabikho kokungaboni, ubungakanani obuncinci besampulu, njl.njl.) kwaye izifundo ezininzi azingqinelani nezinye. "Amandla ophando avelayo" awanantsingiselo kangako kolu ncwadi lungaqondakaliyo. UFrank kufuneka axhomekeke kuphononongo olusondeleyo oluvela kwiiarhente zempilo. Ezi ziye zasilela rhoqo ukufumana ubungqina obucacileyo bemiphumo emibi yeendawo ze-RF ezikufutshane.
UFrank wakhalaza ngokungahambelani ekuxoxeni esidlangalaleni nge-"5G" -- kodwa wenza impazamo efanayo ngokungakhankanyi iibhendi zefrikhwensi xa ebhekisa kwi-5G. Enyanisweni, i-5G yebhendi ephantsi kunye nebhendi ephakathi isebenza kwiifrikhwensi ezikufutshane neebhendi zeselula zangoku kwaye akubonakali ngathi ineengxaki ezintsha zokuvezwa. I-5G yebhendi ephezulu isebenza kwiifrikhwensi ezingaphantsi kancinci koluhlu lwe-mmWave, iqala kwi-30 GHz. Zimbalwa izifundo ezenziweyo kwimiphumo yebhayoloji kolu luhlu lwefrikhwensi, kodwa amandla angena kancinci eluswini, kwaye iiarhente zempilo azikhange ziveze inkxalabo malunga nokhuseleko lwayo kumanqanaba okuvezwa aqhelekileyo.
UFrank akazange acacise ukuba loluphi uphando awayefuna ukulwenza ngaphambi kokuba akhuphe i-"5G," nokuba wayethetha ukuthini. I-[FCC] ifuna ukuba abanini layisenisi banamathele kwimida yokuchatshazelwa kwayo, efana naleyo ikwamanye amazwe amaninzi. Akukho mzekelo wokuba itekhnoloji entsha ye-RF ihlolwe ngokuthe ngqo ngemiphumo yempilo ye-RF ngaphambi kokuba ivunywe, nto leyo enokufuna uthotho lwezifundo ezingapheliyo. Ukuba imiqathango ye-FCC ayikhuselekanga, kufuneka itshintshwe.

Ukuze ufumane uphononongo oluneenkcukacha zophando lweziphumo zebhayoloji ze-5G, jonga inqaku lika-[Ken] Karipidis, elifumanise ukuba "akukho bungqina buqinisekileyo bokuba amasimi e-RF asezantsi ngaphezu kwe-6 GHz, njengalawo asetyenziswa ziinethiwekhi ze-5G, ayingozi kwimpilo yabantu. Olu phononongo lukwacele uphando oluthe kratya.
Uncwadi lwezenzululwazi luxubile, kodwa ukuza kuthi ga ngoku, iiarhente zempilo azikafumani bungqina bucacileyo beengozi zempilo ezivela kwiindawo ze-RF ezikufutshane. Kodwa ngokuqinisekileyo, uncwadi lwezenzululwazi malunga nemiphumo yebhayoloji ye-mmWave luncinci kakhulu, lunezifundo ezimalunga ne-100, kwaye zinomgangatho owahlukileyo.
Urhulumente wenza imali eninzi ngokuthengisa i-spectrum yonxibelelwano lwe-5G, kwaye kufuneka atyale imali ethile kuphando lwezempilo olusemgangathweni, ngakumbi i-5G ephezulu. Mna ngokwam, ndixhalabile kakhulu ngempembelelo enokubakho yexesha elininzi lesikrini kwimiba yophuhliso lomntwana kunye nobumfihlo.
Ngaba kukho iindlela eziphuculweyo zomsebenzi we-dosimetry? Ukuba kunjalo, zeziphi imizekelo enomdla okanye ethembisayo?

Foster: Mhlawumbi inkqubela phambili ephambili ikwi-computational dosimetry ngokuqaliswa kweendlela ze-finite difference time domain (FDTD) kunye neemodeli zamanani zomzimba ezisekelwe kwimifanekiso yezonyango enesisombululo esiphezulu. Oku kuvumela ukubalwa ngokuchanekileyo kokufunxwa kwamandla e-RF ngumzimba kuwo nawuphi na umthombo. I-computational dosimetry inike ubomi obutsha kunyango lwezonyango olusekwe, olufana ne-hyperthermia esetyenziselwa ukunyanga umhlaza, kwaye ikhokelele ekuphuhlisweni kweenkqubo eziphuculweyo ze-MRI imaging kunye nezinye iitekhnoloji ezininzi zonyango.
UMichael Koziol ungumhleli oncedisayo kwi-IEEE Spectrum, egubungela zonke iinkalo zonxibelelwano. Uphumelele kwiYunivesithi yaseSeattle ene-BA kwisiNgesi nakwiFiziksi, kwaye une-MA kwiSayensi yobuNjingalwazi kwiYunivesithi yaseNew York.
Ngo-1992, u-Asad M. Madni wathatha isikhundla se-BEI Sensors and Controls, ejongene nomgca wemveliso owawuquka iintlobo ngeentlobo zeesensors kunye nezixhobo zokuhamba nge-inertial, kodwa wayenenani elincinci labathengi—ngokuyintloko amashishini e-aerospace kunye ne-electronics zokhuselo.

IMfazwe ebandayo yaphela kwaye imboni yezokhuselo yaseMelika yawa. Kwaye ishishini alisayi kuphinda libuyele esiqhelweni kungekudala. I-BEI yayifuna ukuchonga ngokukhawuleza nokutsala abathengi abatsha.
Ukufumana aba bathengi kufuna ukuyeka iinkqubo zesensor ze-inertial zenkampani, kusetyenziswe ubuchwepheshe obutsha be-quartz obungaqinisekanga, ukwenza iisensor ze-quartz zibe zincinci, kunye nokuguqula umenzi ovelisa amashumi amawaka eesensor ezibizayo ngonyaka ukuze avelise izigidi ngezigidi ngexabiso eliphantsi.
UMadni uqhubekile nzima ukuze kwenzeke oku kwaye waphumelela ngaphezu kokuba nabani na ebenokucinga ngeGyroChip. Le sensor yokulinganisa i-inertial engabizi kakhulu yeyokuqala yohlobo lwayo ukufakwa emotweni, ivumela iinkqubo zolawulo lozinzo lwe-elektroniki (ESC) ukuba zibone ukutyibilika kwaye zisebenzise iibhuleki ukuthintela ukuqengqeleka. Njengoko ii-ESC zifakwe kuzo zonke iimoto ezintsha kwixesha leminyaka emihlanu ukusuka ngo-2011 ukuya ku-2015, ezi nkqubo zisindise ubomi babantu abangama-7,000 eMelika kuphela, ngokutsho kweNational Highway Traffic Safety Administration.
Ezi zixhobo zisesembindini weenqwelo-moya ezininzi zorhwebo nezabucala, kunye neenkqubo zokulawula uzinzo kwiinkqubo zokhokelo lweemissile zaseMelika. Zade zaya eMars njengenxalenye yePathfinder Sojourner rover.
Indima yangoku: Unjingalwazi oBalulekileyo kwi-UCLA; UMongameli oThatha umhlala-phantsi, i-CEO kunye ne-CTO ye-BEI Technologies

Imfundo: 1968, kwiKholeji yaseRCA; BS, 1969 kunye no-1972, kwi-MS, e-UCLA, zombini kwiNjineli yoMbane; Ph.D., kwiYunivesithi yaseCalifornia Coast, 1987
Amaqhawe: Ngokubanzi, utata wandifundisa indlela yokufunda, indlela yokuba ngumntu, kunye nentsingiselo yothando, uvelwano, kunye novelwano; kubugcisa, uMichelangelo; kwisayensi, uAlbert Einstein; kubunjineli, uClaude Shannon
Umculo othandwayo: Kumculo waseNtshona, iiBeatles, iiRolling Stones, iiElvis; umculo waseMpuma, iiGhazals
Amalungu ombutho: IEEE Life Fellow; I-US National Academy of Engineering; I-UK Royal Academy of Engineering; I-Canadian Academy of Engineering
Ibhaso elibaluleke kakhulu: I-IEEE Medal of Honor: "Igalelo lokuqala kuphuhliso kunye norhwebo lwetekhnoloji entsha yokuva kunye neenkqubo, kunye nobunkokeli obugqwesileyo bophando"; Abafundi be-UCLA abaphumeleleyo boNyaka ka-2004
UMadni ufumene iMbasa yeNhlonipho ye-IEEE ka-2022 ngokuba nguvulindlela kwiGyroChip, phakathi kwezinye izinto ezinegalelo kuphuhliso lwetekhnoloji kunye nobunkokeli bophando.
Ubunjineli babungengomsebenzi wokuqala kaMadni. Wayefuna ukuba ngumzobi nomculi olungileyo. Kodwa imeko yezemali yosapho lwakhe eMumbai, eIndiya (eyayiyiMumbai ngelo xesha) ngeminyaka yoo-1950 noo-1960 yamguqula waba ngubunjineli—ingakumbi i-elektroniki, ngenxa yomdla wakhe kwizinto ezintsha zamva nje ezikwiirediyasi ze-transistor. Ngo-1966, wafudukela eMelika ukuya kufunda i-elektroniki kwiKholeji yeRCA eNew York City, eyadalwa ekuqaleni kweminyaka yoo-1900 ukuqeqesha abaqhubi bee-wireless kunye neengcali.
“Ndifuna ukuba yinjineli ekwaziyo ukuyila izinto,” utshilo uMadeney, “ndize ndenze izinto eziza kuba nefuthe ebantwini ekugqibeleni. Kuba ukuba andinakuba nefuthe ebantwini, ndivakalelwa kukuba umsebenzi wam awuyi kuzaliseka.”

UMadni wangena e-UCLA ngo-1969 enesidanga se-bachelor kwi-electrical engineering emva kweminyaka emibini kwiprogram ye-Electronics Technology kwi-RCA College. Waqhubeka nokulandela i-master's kunye ne-doctorate, esebenzisa i-digital signal processing kunye ne-frequency domain reflectometry ukuhlalutya iinkqubo zonxibelelwano kuphando lwakhe lwethisisi. Ngexesha lezifundo zakhe, wayekwasebenza njengomfundisi kwiYunivesithi yasePacific State, wasebenza kulawulo lwezinto ezisetyenzisiweyo kwivenkile yaseBeverly Hills uDavid Orgell, kwaye njengonjineli oyila izinto ezisetyenziswa kwikhompyutha ePertec.
Emva koko, ngo-1975, esandul’ ukutshata kwaye enyanzelwa ngomnye owayefunda naye, wafaka isicelo somsebenzi kwisebe le-microwave likaSystron Donner.
UMadni waqala ukuyila i-spectrum analyzer yokuqala ehlabathini ene-digital storage eSystron Donner. Wayengazange asebenzise i-spectrum analyzer ngaphambili—zazibiza kakhulu ngelo xesha—kodwa wayeyazi kakuhle le ngcamango ukuze azikholise ukuba athathe lo msebenzi. Emva koko wachitha iinyanga ezintandathu evavanya, efumana amava okusebenza ngesixhobo ngaphambi kokuba azame ukusiyila ngokutsha.
Le projekthi ithathe iminyaka emibini, kwaye ngokutsho kukaMadni, yaphumela kwiipatenti ezintathu ezibalulekileyo, eqala "ukunyukela kwakhe kwizinto ezinkulu nezingcono." Ikwamfundise ukuqonda umahluko phakathi "kokuthetha ukuba nolwazi lwethiyori kunye nokwenza itekhnoloji yokuthengisa enokunceda abanye," utshilo.

Singakwazi nokwenza ngokwezifiso iinxalenye ze-rf passive ngokweemfuno zakho. Ungangena kwiphepha lokwenza ngokwezifiso ukuze unikeze iinkcukacha ozifunayo.
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