Search

Optimal measurement scheme with an efficient data processing is important in quantum-enhanced interferometry. Here we prove that for a general binary-outcome measurement, the simplest data processing based on inverting the average signal can saturate the Cramér-Rao bound. This idea is illustrated by binary-outcome homodyne detection, even-odd photon counting (i.e., parity detection), and zero-nonzero photon counting that have achieved super-resolved interferometric fringe and shot-noise limited sensitivity in coherent-light Mach-Zehnder interferometer. The roles of phase diffusion are investigated in these binary-outcome measurements. We find that the diffusion degrades the fringe resolution and the achievable phase sensitivity. Our analytical results confirm that the zero-nonzero counting can produce a slightly better sensitivity than that of the parity detection, as demonstrated in a recent experiment. [ABSTRACT FROM AUTHOR]

The crystal structures of a series of new compounds with the composition FeSr2LnCu2O7+δ (Ln = La, Nd, Sm, Eu, Gd, Dy, Ho, Er, and Yb) that were successfully synthesized by solid-state reaction are investigated. The Rietveld refinement of the X-ray diffraction data shows that the samples exhibit a transition from a tetragonal system with space group P4/mmm for light rare earths Ln = La, Nd, Sm, Eu, and Gd to an orthorhombic system with space group Pmmm for heavy rare earths Ln = Dy, Ho, Er, and Yb. The oxygen contents of the samples are chemically determined by the iodometric titration. The room-temperature Mössbauer spectroscopy of ⁵⁷Fe in FeSr2GdCu2O7+δ is used to study the site distribution of Fe between the 1a and 2g sites in the as-synthesized in the air samples and O2-annealed samples, respectively. In the as-synthesized sample, there are about 67% of Fe ions residing in the 1a site, whereas in the O2-annealed sample, there are about 61% of Fe ions residing on the 1a site. Magnetization measurements indicate that χ changes with temperature in a Curie-type manner. Resistance measurements indicate that these samples have a semiconductor-like behavior and their band gap is related to their structural type and the radius of rare earth ions.

The magnetic and electronic transport properties of the compound Pr5Ge4 were investigated by means of magnetic and electrical resistivity measurements. The results indicate that for the compound Pr5Ge4 there are two magnetic transitions at T^IC = 25 K and T^IIC = 41 K in a low field of 500 Oe. In analogy to Nd5Ge4 compound, the magnetic structure of Pr5Ge4 may be a canted one, which can be induced by a competition between nearest-neighbor Pr–Pr ferromagnetic (FM) and Pr–Pr antiferromagnetic (AFM) exchange interactions. The main contribution to the electrical resistivity of Pr5Ge4 is the scattering of conduction electrons on localized magnetic moments. A large magnetoresistance (Δρ/ρ) was observed (about 25% at 24 K and 15% at 40 K) in the presence of a magnetic field of 50 kOe.

We present a method of manipulative reduction, immobilisation and fixation using a U-shaped plaster with the elbow in extension for extension-type supracondylar fractures of the humerus in children. When the elbow is in full extension, both the extensor and the flexor muscles are neutralised during manipulative reduction and the carrying angle can be easily assessed thus preventing cubitus varus, the most common complication.In order to evaluate the efficiency of this method, we compared the clinical results of the new method with those of conventional treatment. In a group of 95 children who sustained an extension-type supracondylar fracture of the humerus, 49 were treated by the new method and 46 by the conventional method, reduction and immobilisation in a plaster slab with the elbow in flexion.Reduction and immobilisation were easily achieved and reliably maintained by one manipulation for all the children treated by the new method. In 12 children treated by the conventional method, the initial reduction failed and in seven secondary displacement of the distal fragment occurred during the period of immobilisation in plaster. All required a second or third manipulation. Of the 46 children, 28 (60.9%) had developed cubitus varus at a mean follow-up of 4.6 years when treated by the conventional method. None of the children treated by the new method developed cubitus varus. The mean score, according to the Hospital for Special Surgery (HSS) elbow scoring system, was 91 points using the new method and 78 with the conventional method. The results were statistically significant with regard to the incidence of cubitus varus and the elbow score (p < 0.01) suggesting that the new method is reliable and gives a satisfactory outcome.

For Abstract see ChemInform Abstract in Full Text.

For Abstract see ChemInform Abstract in Full Text.

For Abstract see ChemInform Abstract in Full Text.

For Abstract see ChemInform Abstract in Full Text.

For Abstract see ChemInform Abstract in Full Text.

For Abstract see ChemInform Abstract in Full Text.

For Abstract see ChemInform Abstract in Full Text.