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91.
We consider two distinct classes of quantum mechanical entanglement. The first "pedigree" class consists of delicate highly entangled states, which hold great potential for use in future quantum technologies. By focusing on Schrodinger cat states, we demonstrate not only the possibilities these states hold but also the difficulties they present. The second "fluffy-bunny" class is made up of robust states that arise naturally as a result of measurements and interactions between particles. This class of entanglement may be responsible for the classical-like world we see around us.  相似文献   
92.
A search was made for 26Mg (26Mg*) from the decay of 26Al (half-life = 0.73 million years) in Al-rich objects from unequilibrated ordinary chondrites. Two Ca-Al-rich inclusions (CAIs) and two Al-rich chondrules (not CAIs) were found that contained 26Al when they formed. Internal isochrons for the CAIs yielded an initial 26Al/27Al ratio [(26Al/27Al)0] of 5 x 10(-5), indistinguishable from most CAIs in carbonaceous chondrites. This result shows that CAIs with this level of 26Al are present throughout the classes of chondrites and strengthens the notion that 26Al was widespread in the early solar system. The two Al-rich chondrules have lower 26Mg*, corresponding to a (26Al/27Al)0 ratio of approximately 9 x 10(-6). Five other Al-rich chondrules contain no resolvable 26Mg*. If chondrules and CAIs formed from an isotopically homogeneous reservoir, then the chondrules with 26Al must have formed or been last altered approximately2 million years after CAIs formed; the 26Mg*-free chondrules formed >1 to 3 million years later still. Because 26Mg*-containing and 26Mg*-free chondrules are both found in Chainpur, which was not heated to more than approximately400°C, it follows that parent body metamorphism cannot explain the absence of 26Mg* in some of these chondrules. Rather, its absence indicates that the lifetime of the solar nebula over which CAIs and chondrules formed extended over approximately5 million years.  相似文献   
93.
Summary One tonne boxes of seed potatoes cv. Désirée contaminated withErwinia carotovora were held in four different types of farm stores. In general, contamination fell rapidly immediately after harvest and rose later in the storage season. The extent of these changes varied considerably with store type. The greatest reduction was from a log count of 5.5 to 2.1 after one month storage, followed by a rise to 5.1 prior to planting. No relationship was found between store temperature, relative humidity and change in contamination. There was some evidence that reduction in contamination was related to duration of ventilation, and rise in contamination to onset of sprouting. A sample held at a constant 4°C showed little reduction in contamination, and no rise occurred later in the storage season.  相似文献   
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The hypothesis that the sticky droppings and the poor performance of chicks fed on low‐enzyme barleys are due to hemicelluloses and related substances in barley, which in solution in the alimentary tract give rise to a highly viscous state, was tested.

It is demonstrated that pectin significantly reduced chick performance and the droppings produced were very sticky. A pectin‐degrading enzyme quickly reduced the viscosity of a solution of pectin and significantly improved the performance of chicks.

The effect of feeding a bacterial enzyme preparation on the viscosity of water extracts of the contents of the small intestines of chickens that were fed on a low‐enzyme barley, was studied. It is shown that the viscosities were reduced by the “enzyme”. The viscosities of extracts from chickens that were fed on barley alone were lowered by enzyme preparations that were effective in increasing the performance of chickens.

Aqueous extracts of Australian barleys, steamed Irish barley and processed Irish barley were highly viscous, whereas similar extracts of raw Irish barleys had very low viscosities. The viscosities of the former barley extracts were markedly lowered by adding “effective” (i.e. those which improve chick performance) enzyme preparations to them.

The “enzymes” gave similar results with a solution of β‐glucan, and it is concluded that the enzyme responsible for lowering the viscosities was endo‐β‐glucanase.

A simple method for the determination of endo‐β‐glucanase activity is described. The activities of Irish barleys were high, but the activities of Australian barleys were very low. The enzyme was present in “effective” crude enzyme preparations.

It is concluded that the poor nutritional value of low‐enzyme barleys is related to the glucan and β‐glucan components of barley. Under the particular conditions the glucan/β‐glucan components give rise to fairly stable highly viscous conditions in the small intestine.  相似文献   

96.
Quadrivalent pairing was observed by electron microscopy of the synaptonemal complex in pachytene spermatocytes in seven out of nine F1 Brahman × Hereford hybrid bulls. The presence of this chromosomal abnormality indicates that the carrier bulls were heterozygous for a reciprocal translocation, which could be contributing to the fertility problems of these hybrid cattle.  相似文献   
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99.
Decision-making and diagnosis in disease management   总被引:4,自引:0,他引:4  
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100.
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