V\u00e0o th\u1ebf k\u1ec9 XIX, nh\u00e0 khoa h\u1ecdc \u0110\u1ee9c, Kran th\u00f4ng qua th\u1ef1c nghi\u1ec7m \u0111\u00e3 ph\u00e1t hi\u1ec7n \u0111\u01b0\u1ee3c: 20 ngh\u00ecn hec l\u00e0 gi\u1edbi h\u1ea1n tr\u00ean c\u1ee7a s\u00f3ng \u00e2m thanh m\u00e0 tai ng\u01b0\u1eddi c\u00f3 th\u1ec3 nghe \u0111\u01b0\u1ee3c. V\u1ec1 sau, ng\u01b0\u1eddi ta g\u1ecdi lo\u1ea1i s\u00f3ng \u00e2m thanh v\u01b0\u1ee3t qu\u00e1 20 ngh\u00ecn hec, tai ng\u01b0\u1eddi kh\u00f4ng th\u1ec3 nghe \u0111\u01b0\u1ee3c l\u00e0 s\u00f3ng si\u00eau \u00e2m (hay \u0111\u01a1n gi\u1ea3n l\u00e0 si\u00eau \u00e2m).<\/p>\n\n\n\n
S\u00f3ng si\u00eau \u00e2m c\u00f3 hai \u0111\u1eb7c t\u00ednh r\u1ea5t quan tr\u1ecdng: m\u1ed9t l\u00e0 t\u00ednh \u0111\u1ecbnh h\u01b0\u1edbng c\u1ee7a n\u00f3. Do t\u1ea7n s\u1ed1 c\u1ee7a s\u00f3ng si\u00eau \u00e2m r\u1ea5t cao, n\u00ean b\u01b0\u1edbc s\u00f3ng r\u1ea5t ng\u1eafn, v\u00ec v\u1eady n\u00f3 c\u00f3 th\u1ec3 truy\u1ec1n theo \u0111\u01b0\u1eddng th\u1eb3ng nh\u01b0 \u00e1nh s\u00e1ng, m\u00e0 kh\u00f4ng gi\u1ed1ng nh\u1eefng s\u00f3ng \u00e2m c\u00f3 b\u01b0\u1edbc s\u00f3ng t\u01b0\u01a1ng \u0111\u1ed1i d\u00e0i c\u00f3 th\u1ec3 \u0111i v\u00f2ng qua v\u1eadt th\u1ec3. Khi g\u1eb7p ph\u1ea3i v\u1eadt ch\u01b0\u1edbng ng\u1ea1i, s\u00f3ng si\u00eau \u00e2m s\u1ebd ph\u1ea3n x\u1ea1 l\u1ea1i. Th\u00f4ng qua vi\u1ec7c thu nh\u1eadn v\u00e0 ph\u00e2n t\u00edch s\u00f3ng ph\u1ea3n x\u1ea1 c\u00f3 th\u1ec3 \u0111o \u0111\u01b0\u1ee3c h\u01b0\u1edbng v\u00e0 kho\u1ea3ng c\u00e1ch c\u1ee7a v\u1eadt ch\u01b0\u1edbng ng\u1ea1i. Trong gi\u1edbi t\u1ef1 nhi\u00ean, con d\u01a1i ch\u00ednh l\u00e0 \u0111\u1ed9ng v\u1eadt d\u00f9ng m\u1ed3m ph\u00e1t ra s\u00f3ng si\u00eau \u00e2m, d\u00f9ng tai thu nh\u1eadn s\u00f3ng ph\u1ea3n x\u1ea1 \u0111\u1ec3 nh\u1eadn ra v\u1eadt ch\u01b0\u1edbng ng\u1ea1i. V\u00ec v\u1eady, n\u00f3 c\u00f3 th\u1ec3 t\u1ef1 do bay l\u01b0\u1ee3n trong hang \u0111\u1ed9ng t\u1ed1i m\u00f2, l\u1ea1i c\u00f2n c\u00f3 th\u1ec3 ch\u1ed9p b\u1eaft chu\u1ea9n x\u00e1c nh\u1eefng c\u00f4n tr\u00f9ng nh\u1ecf c\u00f3 c\u00e1nh n\u1eefa!<\/p>\n\n\n\n
\u0110\u1eb7c t\u00ednh th\u1ee9 hai c\u1ee7a s\u00f3ng si\u00eau \u00e2m l\u00e0 n\u00f3 c\u00f3 th\u1ec3 truy\u1ec1n \u0111\u1ebfn kho\u1ea3ng c\u00e1ch r\u1ea5t xa trong n\u01b0\u1edbc. Trong kh\u00f4ng kh\u00ed, s\u00f3ng si\u00eau \u00e2m 30 ngh\u00ecn hec truy\u1ec1n \u0111i 24 m, c\u01b0\u1eddng \u0111\u1ed9 suy gi\u1ea3m h\u01a1n m\u1ed9t n\u1eeda; c\u00f2n \u1edf trong n\u01b0\u1edbc, n\u00f3 truy\u1ec1n \u0111i 44 km c\u01b0\u1eddng \u0111\u1ed9 m\u1edbi suy gi\u1ea3m m\u1ed9t n\u1eeda, g\u1ea5p 2000 l\u1ea7n kho\u1ea3ng c\u00e1ch truy\u1ec1n trong kh\u00f4ng kh\u00ed. Do \u00e1nh s\u00e1ng v\u00e0 c\u00e1c lo\u1ea1i s\u00f3ng \u0111i\u1ec7n t\u1eeb kh\u00e1c truy\u1ec1n kh\u00f3 kh\u0103n trong n\u01b0\u1edbc, truy\u1ec1n ch\u1eb3ng \u0111\u01b0\u1ee3c bao xa, n\u00ean s\u00f3ng si\u00eau \u00e2m \u0111\u00e3 tr\u1edf th\u00e0nh c\u00f4ng c\u1ee5 s\u1ed1 m\u1ed9t trong vi\u1ec7c th\u0103m d\u00f2 c\u00e1c v\u1eadt th\u1ec3 d\u01b0\u1edbi n\u01b0\u1edbc.<\/p>\n\n\n\n
Trong th\u1eddi k\u00ec Chi\u1ebfn tranh th\u1ebf gi\u1edbi l\u1ea7n th\u1ee9 nh\u1ea5t, t\u00e0u ng\u1ea7m c\u1ee7a \u0110\u1ee9c d\u1ef1a v\u00e0o bi\u1ec3n c\u1ea3 m\u00eanh m\u00f4ng l\u00e0m l\u00e1 ch\u1eafn, t\u1edbi t\u1ea5p t\u1ea5n c\u00f4ng c\u00e1c t\u00e0u tu\u1ea7n ph\u00f2ng c\u1ee7a Anh v\u00e0 Ph\u00e1p. L\u00fac b\u1ea5y gi\u1edd, nh\u00e0 khoa h\u1ecdc Ph\u00e1p Langevin, l\u00f2ng d\u1ea1 nh\u01b0 l\u1eeda \u0111\u1ed1t, tr\u1ea3i qua kh\u1ed5 c\u00f4ng nghi\u00ean c\u1ee9u, \u00f4ng \u0111\u00e3 ph\u00e1t minh ra m\u1ed9t lo\u1ea1i m\u00e1y g\u1ecdi l\u00e0 sona. N\u00f3 do b\u1ed9 ph\u1eadn ph\u00e1t s\u00f3ng si\u00eau \u00e2m v\u00e0 b\u1ed9 ph\u1eadn thu s\u00f3ng si\u00eau \u00e2m h\u1ee3p th\u00e0nh. B\u1ed9 ph\u1eadn ph\u00e1t ch\u1ee7 \u0111\u1ed9ng ph\u00e1t ra s\u00f3ng si\u00eau \u00e2m, b\u1ed9 ph\u1eadn thu thu nh\u1eadn v\u00e0 \u0111o \u0111\u1ea1c c\u00e1c lo\u1ea1i h\u1ed3i \u00e2m. Th\u00f4ng qua vi\u1ec7c t\u00ednh qu\u00e3ng th\u1eddi gian gi\u1eefa ph\u00e1t v\u00e0 thu t\u00edn hi\u1ec7u \u0111\u1ec3 ph\u00e1t hi\u1ec7n c\u00e1c lo\u1ea1i m\u1ee5c ti\u00eau. Lo\u1ea1i sona ch\u1ee7 \u0111\u1ed9ng tinh x\u1ea3o kh\u00f4ng nh\u1eefng c\u00f3 th\u1ec3 x\u00e1c \u0111\u1ecbnh v\u1ecb tr\u00ed, h\u00ecnh d\u1ea1ng c\u1ee7a m\u1ee5c ti\u00eau, m\u00e0 c\u00f2n c\u00f3 th\u1ec3 ph\u00e2n t\u00edch ra t\u00ednh n\u0103ng c\u1ee7a t\u00e0u ng\u1ea7m \u0111\u1ecbch.<\/p>\n\n\n\n
Trong th\u1eddi k\u00ec ho\u00e0 b\u00ecnh, k\u0129 thu\u1eadt sona c\u00f2n \u0111\u01b0\u1ee3c d\u00f9ng \u0111\u1ec3 th\u0103m d\u00f2 \u0111\u00e0n c\u00e1, ph\u00e1t hi\u1ec7n \u0111\u00e1 ng\u1ea7m, d\u1eabn \u0111\u01b0\u1eddng ra v\u00e0o c\u00e1c c\u1ea3ng bi\u1ec3n v.v. D\u00f9ng sona qu\u00e9t m\u1eb7t b\u00ean hi\u1ec7n \u0111\u1ea1i \u0111\u1ec3 kh\u1ea3o s\u00e1t t\u00ecnh tr\u1ea1ng \u0111\u00e1y bi\u1ec3n, n\u00f3 c\u00f3 th\u1ec3 v\u1ebd l\u1ea1i \u0111\u1ecba m\u1ea1o \u0111\u00e1y bi\u1ec3n m\u1ed9t c\u00e1ch r\u00f5 r\u00e0ng l\u00ean gi\u1ea5y v\u1ebd, cho ra “b\u1ea3n \u0111\u1ed3 \u0111\u1ecba m\u1ea1o si\u00eau \u00e2m” ch\u00ednh x\u00e1c, sai s\u1ed1 kh\u00f4ng qu\u00e1 20 cm.<\/p>\n\n\n\n
C\u0169ng v\u1edbi nguy\u00ean l\u00ed \u1ea5y, vi\u1ec7c \u0111\u01b0a s\u00f3ng si\u00eau \u00e2m v\u00e0o trong c\u01a1 th\u1ec3 ng\u01b0\u1eddi, s\u00f3ng ph\u1ea3n x\u1ea1 sinh ra qua x\u1eed l\u00ed c\u1ee7a thi\u1ebft b\u1ecb \u0111i\u1ec7n t\u1eed, tr\u00ean m\u00e0n h\u00ecnh s\u1ebd hi\u1ec7n ra h\u00ecnh \u1ea3nh r\u00f5 n\u00e9t, ph\u1ea3n \u00e1nh \u0111\u1ea7y \u0111\u1ee7 chi ti\u1ebft v\u1ec1 k\u00edch th\u01b0\u1edbc, v\u1ecb tr\u00ed, m\u1ed1i quan h\u1ec7 qua l\u1ea1i v\u00e0 t\u00ecnh tr\u1ea1ng sinh l\u00ed c\u1ee7a n\u1ed9i t\u1ea1ng c\u01a1 th\u1ec3. Trong b\u1ec7nh vi\u1ec7n th\u01b0\u1eddng d\u00f9ng s\u00f3ng si\u00eau \u00e2m lo\u1ea1i B \u0111\u1ec3 ki\u1ec3m tra gan, t\u00fai m\u1eadt, t\u1ee5y v\u00e0 c\u00e1c c\u01a1 quan n\u1ed9i t\u1ea1ng quan tr\u1ecdng nh\u01b0 t\u1eed cung, h\u1ed1 ch\u1eadu, bu\u1ed3ng tr\u1ee9ng v.v., k\u1ecbp th\u1eddi ph\u00e1t hi\u1ec7n c\u00e1c bi\u1ebfn \u0111\u1ed5i b\u1ec7nh l\u00ed nh\u01b0 k\u1ebft s\u1ecfi, c\u1ee5c u v.v. D\u1ef1a v\u00e0o s\u00f3ng si\u00eau \u00e2m, c\u00e1c b\u00e1c s\u0129 c\u00f2n c\u00f3 th\u1ec3 ti\u1ebfn h\u00e0nh ki\u1ec3m tra thai nhi trong b\u1ee5ng ph\u1ee5 n\u1eef c\u00f3 mang.<\/p>\n\n\n\n
Ngo\u00e0i ra, c\u00f2n \u1ee9ng d\u1ee5ng nguy\u00ean l\u00ed ki\u1ec3m tra \u0111o \u0111\u1ea1c b\u1eb1ng s\u00f3ng si\u00eau \u00e2m trong c\u00e1c c\u00f4ng tr\u00ecnh, t\u1ee9c l\u00e0 l\u0129nh v\u1ef1c th\u0103m d\u00f2 khuy\u1ebft t\u1eadt b\u1eb1ng si\u00eau \u00e2m. Ch\u1ec9 c\u1ea7n ph\u00e1t m\u1ed9t ch\u00f9m s\u00f3ng si\u00eau \u00e2m l\u00ean c\u00e1c chi ti\u1ebft m\u00e1y, n\u1ebfu trong \u0111\u00f3 c\u00f3 \u1ea9n ch\u1ee9a v\u1ebft n\u1ee9t, ch\u1ed7 r\u1ed7, b\u1ecdt kh\u00ed v.v., s\u00f3ng si\u00eau \u00e2m li\u1ec1n sinh ra s\u00f3ng ph\u1ea3n x\u1ea1 kh\u00f4ng b\u00ecnh th\u01b0\u1eddng, cho d\u00f9 khuy\u1ebft t\u1eadt c\u00f3 nh\u1ecf \u0111\u1ebfn \u0111\u00e2u c\u0169ng kh\u00f4ng tho\u00e1t kh\u1ecfi s\u1ef1 ki\u1ec3m tra c\u1ee7a n\u00f3. S\u00f3ng si\u00eau \u00e2m \u0111\u00e3 tr\u1edf th\u00e0nh “con m\u1eaft” s\u00e1ng ng\u1eddi c\u1ee7a c\u00e1c k\u0129 s\u01b0.<\/p>\n\n\n\n
T\u1eeb kh\u00f3a: S\u00f3ng si\u00eau \u00e2m; Sona; Si\u00eau \u00e2m B; Th\u0103m d\u00f2 khuy\u1ebft t\u1eadt b\u1eb1ng si\u00eau<\/p>\n\n\n\n
<\/p>\n\n\n\n\n\n\n","protected":false},"excerpt":{"rendered":"
V\u00e0o th\u1ebf k\u1ec9 XIX, nh\u00e0 khoa h\u1ecdc \u0110\u1ee9c, Kran th\u00f4ng qua th\u1ef1c nghi\u1ec7m \u0111\u00e3 ph\u00e1t hi\u1ec7n \u0111\u01b0\u1ee3c: 20 ngh\u00ecn hec l\u00e0 gi\u1edbi h\u1ea1n tr\u00ean c\u1ee7a s\u00f3ng \u00e2m thanh m\u00e0 tai ng\u01b0\u1eddi c\u00f3 th\u1ec3 nghe \u0111\u01b0\u1ee3c. V\u1ec1 sau, ng\u01b0\u1eddi ta g\u1ecdi lo\u1ea1i s\u00f3ng \u00e2m thanh v\u01b0\u1ee3t qu\u00e1 20 ngh\u00ecn hec, tai ng\u01b0\u1eddi kh\u00f4ng th\u1ec3 nghe \u0111\u01b0\u1ee3c […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","_disable_autopaging":false},"categories":[15,7],"tags":[],"class_list":["post-5624","post","type-post","status-publish","format-standard","hentry","category-hoi-dap-khoa-hoc","category-vat-ly"],"_links":{"self":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/5624","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/comments?post=5624"}],"version-history":[{"count":0,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/5624\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/media?parent=5624"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/categories?post=5624"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/tags?post=5624"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}