Results 121 to 130 of about 97,526 (278)
Multiple Roles of Protamine Kinase SRPK1 and Phosphatase PP1γ in Sperm Development
PROTEOMICS, EarlyView.ABSTRACT Protein phosphorylation regulates key events of male germ cell differentiation. In the testis, SRPK1 and PP1γ are involved in protamine phosphorylation and dephosphorylation, respectively, and their deregulation is linked to defective chromatin structure and male infertility.
Alberto de la Iglesia +7 more
wiley +1 more source
Irradiation of Sperm Tails by Laser Microbeam [PDF]
, 1969 1. Sea-urchin and starfish sperm tails were irradiated at pre-selected points along the flagellum and at pre-selected phases of the beat cycle by means of a pulsed ruby laser microbeam. Multiple-exposure dark-field photomicrographs were taken immediately
Goldstein, Stuart F.
core
Responsive Materials, EarlyView.We systematically summarize how each scale dictates fundamental choices in design feature, manufacturing technology, driving mechanism, and control strategy, which are inherently governed by scale‐dominated physical principles. Furthermore, the application of scale‐determined operation modes of microrobots across different stages of medical ...
Hang Yin +3 more
wiley +1 more source
Force-extension curves of bacterial flagella
, 2010 Bacterial flagella assume different helical shapes during the tumbling phase of a bacterium but also in response to varying environmental conditions. Force-extension measurements by Darnton and Berg explicitly demonstrate a transformation from the coiled
Stark, Holger, Vogel, Reinhard
core +1 more source
Environmental Toxicology, EarlyView.ABSTRACT Plastic, with its remarkable versatility and numerous applications, has greatly benefited humanity. However, its extreme resistance to natural degradation means it persists in the environment for long periods, causing global environmental problems.
Teresa Chianese +13 more
wiley +1 more source
Tuning the torque-speed characteristics of bacterial flagellar motor to enhance the swimming speed
, 2019 In a classic paper, Edward Purcell analysed the dynamics of flagellated bacterial swimmers and derived a geometrical relationship which optimizes the propulsion efficiency. Experimental measurements for wild-type bacterial species E.
Abdulla, Amith Z. +3 more
core +1 more source
Effects of Glyphosate on the Planktonic Microbiota: An Experimental Approach
Environmental Toxicology, EarlyView.ABSTRACT Glyphosate is one of the most widely used herbicides in the world, including in Brazil, and its dispersion through habitats and surface waters can impact entire aquatic ecosystems. However, experimental studies evaluating the effects of pesticides on whole planktonic communities, considering attributes such as richness, density and composition—
Melissa Progênio +7 more
wiley +1 more source
Environmental Toxicology, EarlyView.ABSTRACT Mining plays a crucial role in economic development, but improper management can lead to severe environmental degradation. Particularly for iron ore, mining generates vast amounts of tailings often stored in unstable dams. This study aims to investigate the toxicological impacts of environmentally relevant concentrations of metals mixture ...
Kalinka Helóra Gomes de Almeida +7 more
wiley +1 more source
Flagellar dynamics of chains of active Janus particles fueled by an AC electric field
New Journal of Physics, 2018 We study the active dynamics of self-propelled asymmetrical colloidal particles (Janus particles) fueled by an AC electric field. Both the speed and direction of the self-propulsion, and the strength of the attractive interaction between particles can be
Daiki Nishiguchi +3 more
doaj +1 more source
Structure and behaviour of the sperm terminal filament [PDF]
, 1982 Light- and electron-microscopic observations of Ciona and Lytechinus spermatozoa show a thin terminal filament at the distal end. The terminal filament is 5-6 microns long and contains the two central microtubules and a variable number of A-tubule ...
Brokaw, C. J., Omoto, C. K.
core