Flagellar beating drives sperm through the female reproductive tract and is vital for reproduction. Flagellar waves are generated by thousands of asymmetric molecular components; yet, paradoxically, forward swimming arises via symmetric side-to-side flagellar movement. This led to the preponderance of symmetric flagellar control hypotheses. However, molecular asymmetries must still dictate the flagellum and be manifested in the beat. Here, we reconcile molecular and microscopic observations, reconnecting structure to function, by showing that human sperm uses asymmetric and anisotropic controls to swim. High-speed three-dimensional (3D) microscopy revealed two coactive transversal controls: An asymmetric traveling wave creates a one-sided stroke, and a pulsating standing wave rotates the sperm to move equally on all sides. Symmetry is thus achieved through asymmetry, creating the optical illusion of bilateral symmetry in 2D microscopy. This shows that the sperm flagellum is asymmetrically controlled and anisotropically…

Яна, здравствуйте! Ищу совета. Ситуация такая: Мне 33, у меня двое маленьких детей и мы с мужем живем за 1500 км от моих родителей. У меня есть папа, ему 73 и Мама, ей 60, они живут в крупном городе и Мама работает, и даже часто ездит в командировки. И вот Папа заболел, что-то по мужской части…

Директор департамента радиоэлектронной промышленности Минпромторга России Василий Шпак сообщил журналистам, что в России нашли утюги иностранного производства... РИА Новости, 30.09.2020

It’s been a year since I ‘ve started this Instagram account and I started it with post for #inktoberchallenge Though I won’t be participating this year still decided to do at least one sketch in ink🖤 . . . #inktober2020day1 #inktober2020 #inktober #fish #dailysketch #digitalart #inkonpaper #inking #drawing #inktober_fish #sketchbook #blackandwhite #sketching #lineart #ink