Bull sperm extracted with 0.1% Triton X-100 can be reactivated to full motility with 0.33 mM Mg-ATP (sperm models). When motile sperm models are treated with 0.66 mM NiSO4, spontaneous motility is lost. During the transition to motility arrest, the beat becomes progressively more asymmetric, finally arresting at one extreme of the beat cycle. After spontaneous motility has been lost, the flagel...

You who more than oncespelled angle when meaning angel,are now one—maybe both.A sharp line on white paperdriving hardand fastin another spacewhose numbersI do not know.YetIn the arithmeticof our individual journeys,let us incline,My dearest angle,toward that vertexthat despite variantswe bend,infinite together,while angels math.

We consider right angle crossing (RAC) drawings of graphs in which the edges are represented by polygonal arcs and any two edges can cross only at a right angle. We show that if a graph with n vertices admits a RAC drawing with at most 1 bend or 2 bends per edge, then the number of edges is at most 6.5n and 74.2n, respectively. This is a strengthening of a recent result of Didimo et al.

Secondary and tertiary structures of tRNAs are remarkably preserved from bacteria to humans, the notable exception being the mitochondrial (m) tRNAs of metazoans, which often deviate substantially from the canonical cloverleaf (secondary) or 'L'-shaped (tertiary) structure. Many metazoan mtRNAs lack either the TpsiC (T) or dihydrouridine (D) loops of the canonical cloverleaf, which are known to...

The kinematics of turning manoeuvres and the distance-time performance in escape responses of startled angelfish {Pterophyllum eimekei) are investigated employing high-speed cinematography (400Hz). All escape responses observed are C-type fast-starts, in which the fish assumes a C shape at the end of the initial body contraction (stage 1). Kinematic analysis of the subsequent stage (stage 2) al...

We present multi-epoch multi-frequency VLBI images of the compact polarized radio structure of the quasar 4C 39.25. Between 1995 and 1999, the total intensity images at 15, 22, and 43 GHz have remained almost unperturbed, while there have been significant changes in the polarized intensity maps together with a related rotation of the polarization angle. These changes in the polarized structure ...

Linear collider designs foresee some bends of about 5-10 mrad. The spin precession angle of one TeV electrons on 10 mrad bend is 23.2 rad and it changes proportional to the energy. Measurement of the spin direction using Compton scattering of laser light on electrons before and after the bend allows determining the beam energy with an accuracy about of 10. In this paper the principle of the met...

Lent’ and also 301s and Macucci* have carried out numerical calculations for transmission and bound states of a quantum wire with a circular bend. We shall show here that their results can be understood in detail, and very simply,. in the approximation introduced by Jensen and Koppe3 that the width of the wire is small compared to its radius of curvature. As we shall see, the results are excell...

A fiber optical inclinometer based on modal interferometer is demonstrated for bend angle sensing. The device consists of a piece of simplified hollow core photonic crystal fiber sandwiched between single mode fibers with lateral offset. The measurement of bend angles up to 45° is demonstrated, and the spectrum exhibits a blueshift of over 50 nm. The sensitivity is found to increase with the ap...

NeP1 binds to the F1 silencer element of the chicken lysozyme gene and, in the presence of TR, v-ERBA or RAR, synergistically represses transcriptional activity. This repression involves a silencing mechanism acting independently of the relative promoter position. Here we show that NeP1 alone can induce a significant directed bend on DNA. The chicken homologue of human NeP1, CTCF, shows identic...