Various Gallus varius hybrids: variation in junglefowl hybrids and Darwin's interest in them

Hybrids between Green Junglefowl Gallus varius and domestic fowl G. gallus domesticus confused several 19th-century ornithologists. The plumage of these hybrids is so unlike the colours and patterns of either of the parent species that they were considered to be distinct species: G. aeneusTemminck, 1825; G. temminckiiGray, 1849; and G. violaceusKelsall, 1891. Darwin wanted to understand if G. aeneus and G. temminckii were hybrids or species, as part of his research on the origin of the domestic chicken. His view was that all domesticated fowl have a single wild ancestor, Red Junglefowl G. gallus (formerly G. bankiva). A hybrid specimen now present in the bird collection of the Natural History Museum at Tring played an important role in Darwin's reasoning and, although the conclusions he drew from this specimen were incorrect, his single-ancestor origin theory for domesticated fowl stands. ‘These hybrids were at one time thought to be specifically distinct, and were named G. aeneus. Mr. Blyth and others believe that the G. Temminckii is a similar hybrid' (Darwin 1868a: 234–235).© 2019 The Authors; This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. The attached file is the published pdf

Amplified wind turbine apparatus

An invention related to the utilization of wind energy and increasing the effects thereof for power generation is described. Amplified wind turbine apparatus is disclosed wherein ambient inlet air is prerotated in a first air rotation chamber having a high pressure profile increasing the turbulence and Reynolds number thereof. A second rotation chamber adjacent and downstream of the turbine has a low pressure core profile whereby flow across the turbine is accelerated and thereafter exits the turbine apparatus through a draft anti-interference device. Interference with ambient winds at the outlet of the turbine apparatus is thus eliminated. Pivotable vanes controlled in response to prevailing wind direction admit air to the chambers and aid in imparting rotation. A central core may be utilized for creating the desired pressure profile in the chamber

Mechanical solar motor: A concept

Motor is proposed to convert radiation from sun directly into mechanical energy. Motor utilizes thermal expansion of liquid, heated by sun, as driving force. Unlike most thermally powered systems, it does not require that liquid be converted into vapor

Mechanical thermal motor

An apparatus is described for converting thermal energy such as solar energy into mechanical motion for driving fluid pumps and similar equipment. The thermal motor comprises an inner concentric cylinder carried by a stationary core member. The core member has a cylindrical disc plate fixed adjacent to a lower portion and extending radially from it. An outer concentric cylinder rotatably carried on the disc plate defining a space between the inner and outer concentric cylinders. A spiral tubular member encircles the inner concentric cylinder and is contained within the space between the inner and outer cylinders. One portion is connected to the inner concentric cylinder and a second portion connected to the outer concentric cylinder. A heated fluid is conveyed through the tubular member and is periodically cooled causing the tubular member to expand and contract. This causes the outer concentric cylinder to reciprocally rotate on the base plate accordingly. The reciprocating motion of the outer concentric cylinder is then utilized to drive a pump member in a pump chamber

Entanglement properties of multipartite entangled states under the influence of decoherence

We investigate entanglement properties of multipartite states under the influence of decoherence. We show that the lifetime of (distillable) entanglement for GHZ-type superposition states decreases with the size of the system, while for a class of other states -namely all graph states with constant degree- the lifetime is independent of the system size. We show that these results are largely independent of the specific decoherence model and are in particular valid for all models which deal with individual couplings of particles to independent environments, described by some quantum optical master equation of Lindblad form. For GHZ states, we derive analytic expressions for the lifetime of distillable entanglement and determine when the state becomes fully separable. For all graph states, we derive lower and upper bounds on the lifetime of entanglement. To this aim, we establish a method to calculate the spectrum of the partial transposition for all mixed states which are diagonal in a graph state basis. We also consider entanglement between different groups of particles and determine the corresponding lifetimes as well as the change of the kind of entanglement with time. This enables us to investigate the behavior of entanglement under re-scaling and in the limit of large (infinite) number of particles. Finally we investigate the lifetime of encoded quantum superposition states and show that one can define an effective time in the encoded system which can be orders of magnitude smaller than the physical time. This provides an alternative view on quantum error correction and examples of states whose lifetime of entanglement (between groups of particles) in fact increases with the size of the system.Comment: 27 pages, 11 figure

The dynamics and estimation of short-run money demand

Demand for money

The wayward money supply: a post-mortem of 1982

Money supply

The shift in money demand: what really happened?

Demand for money

Evidence on the temporal stability of the demand for money relationship in the United States

Demand for money

Monetary policy and short-term real rates of interest

Monetary policy ; Interest rates