2,425,151 research outputs found
In Vitro Fertility of Post-thawed Epididymal Ram Spermatozoa After Storage at 5 °C Before Cryopreservation
This study addressed the effects of storage duration of epididymides at 5 °C before sperm collection and their fertility after cryopreservation in vitro. Spermatozoa from one of the testes pairs were immediately collected, evaluated and frozen (control group). The remaining epididymides were cooled to 5 °C and stored for 24, 48, 72, and 96 h (experimental groups), after which spermatozoa were collected and frozen as in the control group. Before and after thawing, sperm motility, sperm viability and plasma membrane integrity were assessed. The fertilizing ability of frozen-thawed spermatozoa of each group was evaluated by in vitro fertilization of matured sheep oocytes. Sperm quality (sperm motility, viability, and plasma membrane integrity) at collection and after cryopreservation decreased as the duration of the epididymal storage interval increase (P < 0.05). The motility decreased steadily along the studied time periods. Although, the fertilizing ability of post-thawed epididymal spermatozoa gradually decreased as the storage period was prolonged, the spermatozoa collected from the cauda epididymides stored at 5 °C for up to 96 h were able to fertilize 16%-65% of oocytes in vitro. Results of the present study showed that ram epididymal spermatozoa survive in storage at 5 °C for up to 96 h. These spermatozoa maintain their fertilizing ability and may be suitable for use in IVF and other assisted reproductive procedures
D=11 supergravity with manifest supersymmetry
The complete supersymmetric action for eleven-dimensional supergravity is
presented. The action is polynomial in the scalar fermionic pure spinor
superfield, and contains only a minor modification to the recently proposed
three-point coupling.Comment: 14 pp., plain te
Stochastic Navier-Stokes equation and advection of a tracer field: One-loop renormalization near
The renormalization group approach and the operator product expansion
technique are applied to the model of a tracer field advected by the
Navier-Stokes velocity ensemble for a compressible fluid. The model is
considered in the vicinity of the specific space dimension . The
properties of the equal-time structure functions are investigated. The
multifractal behaviour of various correlation functions is established. All
calculations are performed in the leading one-loop approximation.Comment: 8 pages, 1 figur
Kinetics of Deposition of Oriented Superdisks
We use numerical Monte Carlo simulation to study kinetics of deposition of
oriented superdisks, bounded by the Lame curves of the form
, on regular planar substrate. It was recently shown that
the maximum packing density, as well as jamming density , exhibit
discontinuous derivative at , when the shape changes from convex to
concave form. By careful examination of the late-stage approach to the jamming
limit, we find that the leading term in temporal development is also
nonanalytic at , and offer heuristic excluded-area arguments for this
behavior
A survey on performance analysis of warehouse carousel systems
This paper gives an overview of recent research on the performance evaluation and design of carousel systems. We discuss picking strategies for problems involving one carousel, consider the throughput of the system for problems involving two carousels, give an overview of related problems in this area, and present an extensive literature review. Emphasis has been given on future research directions in this area
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