25,703 research outputs found
A multiplex PCR assay for differentiating economically important gastrointestinal nematodes of cattle
A multiplex polymerase chain reaction (PCR) test was developed for identifying gastrointestinal (GI) nematodes that commonly infect cattle. This assay was developed using adult-derived genomic DNA and shown capable of discriminating parasite eggs from the feces of experimentally-infected animals at both the species and genus levels. Sequence data from internal (ITS) and external (ETS) transcribed spacers of the ribosomal DNA (rDNA) repeats as well as the 3′-end of the small subunit rDNA and 5′-end of the large subunit rDNA were used to generate five primer sets which, when used simultaneously in a multiplex PCR, produce a unique electrophoretic DNA banding pattern charac- terized by a single DNA fragment for Ostertagia ostertagi (257 bp), Haemonchus placei (176 bp),Oesophagostomum radiatum (329 bp), Trichostrongylus colubriformis (243 bp) and Cooperia on- cophora (151 bp). In a similar manner, the constructed primer sets amplified DNA from Ostertagia lyrata, Haemonchus contortus, Trichostrongylus axei, Cooperia surnabada and Cooperia punctata. With respect to H. contortus, a closely migrating doublet was generated suggesting size heterogene- ity in the ETS which is consistent with multiple rDNA repeat units within this species. PCR analyses using mixtures of monospecifically-purified nematode eggs indicated a sensitivity of less than 0.5 egg-DNA equivalent per species. Although, not designed as a quantitative technique, relative PCR signal intensities corresponded to relative egg burdens within the DNA samples from mixed species of eggs. Published by Elsevier Science B.V
Quantum-secured imaging
We have built an imaging system that uses a photon's position or
time-of-flight information to image an object, while using the photon's
polarization for security. This ability allows us to obtain an image which is
secure against an attack in which the object being imaged intercepts and
resends the imaging photons with modified information. Popularly known as
"jamming," this type of attack is commonly directed at active imaging systems
such as radar. In order to jam our imaging system, the object must disturb the
delicate quantum state of the imaging photons, thus introducing statistical
errors that reveal its activity.Comment: 10 pages (double spaced), 5 figure
Spatial and Temporal Hadron Correlators below and above the Chiral Phase Transition
Hadronic correlation functions at finite temperature in QCD, with four
flavours of dynamical quarks, have been analyzed both above and below the
chiral symmetry restoration temperature. We have used both point and extended
sources for spatial as well as temporal correlators. The effect of periodic
temporal boundary conditions for the valence quarks on the spatial meson
correlators has also been investigated. All our results are consistent with the
existence of individual quarks at high temperatures. A measurement of the
residual interaction between the quarks is presented.Comment: 19 pages HLRZ 54/93, BI-TP 93/76, TIFR/TH/94-1
Symmetric extension in two-way quantum key distribution
We introduce symmetric extensions of bipartite quantum states as a tool for
analyzing protocols that distill secret key from quantum correlations. Whether
the correlations are coming from a prepare-and-measure quantum key distribution
scheme or from an entanglement-based scheme, the protocol has to produce
effective states without a symmetric extension in order to succeed. By
formulating the symmetric extension problem as a semidefinite program, we solve
the problem for Bell-diagonal states. Applying this result to the six-state and
BB84 schemes, we show that for the entangled states that cannot be distilled by
current key distillation procedures, the failure can be understood in terms of
a failure to break a symmetric extension.Comment: 11 pages, 2 figures; v2: published version, hyperlinked reference
Dynamic Energy Management
We present a unified method, based on convex optimization, for managing the
power produced and consumed by a network of devices over time. We start with
the simple setting of optimizing power flows in a static network, and then
proceed to the case of optimizing dynamic power flows, i.e., power flows that
change with time over a horizon. We leverage this to develop a real-time
control strategy, model predictive control, which at each time step solves a
dynamic power flow optimization problem, using forecasts of future quantities
such as demands, capacities, or prices, to choose the current power flow
values. Finally, we consider a useful extension of model predictive control
that explicitly accounts for uncertainty in the forecasts. We mirror our
framework with an object-oriented software implementation, an open-source
Python library for planning and controlling power flows at any scale. We
demonstrate our method with various examples. Appendices give more detail about
the package, and describe some basic but very effective methods for
constructing forecasts from historical data.Comment: 63 pages, 15 figures, accompanying open source librar
REAL PROPERTY-VALIDITY OF REGULATIONS OR CONDITIONS IMPOSED UPON SUBDIVISION PLANNING
The plaintiff, wishing to subdivide its land fronting on Long Island Sound, submitted its plan to the town planning and zoning board whose approval was required by ordinance before land could be subdivided and sold. The board rejected plaintiff\u27s plan as not in conformance with a preliminary town plan, adopted in 1936 pursuant to a state statute, providing for the prospective construction of a road along the shore of the sound. The plaintiff appealed to the board of zoning appeals, which affirmed the decision of the town planning and zoning board. On appeal to the Supreme Court of Errors of Connecticut, held, reversed. A preliminary town plan, adopted without notice to affected property owners and without opportunity for them to be heard, cannot curtail the rights of such owners or limit them in the use of their land. Lordship Park Assn. v. Board of Zoning Appeals of Town of Stratford, (Conn. 1950) 75 A. (2d) 379
AGENCY-ELECTION TO SUE UNDISCLOSED PRINCIPAL OR AGENT
Plaintiff brought action against a principal and his agent to foreclose a mechanic\u27s lien on the principal\u27s real property, alleging that he had expended labor and materials in the improvement of the principal\u27s land pursuant to a contract between himself and the agent. Though plaintiff joined the agent as a party defendant, he did not pray for relief against him. Both defendants moved to dismiss the action. Held, action dismissed as to the agent. Whether or not the principal was disclosed at the time the contract arose, the action was properly dismissed as against the agent. If the principal was disclosed, the agent was not liable on the contract; and if the principal was undisclosed, the creditor had to elect whether to proceed against the agent or the principal. Failure to seek relief against the agent constituted an election to sue the principal. Campbell v. Murdock, (D.C. Ohio 1950) 90 F. Supp. 297
CONSTITUTIONAL LAW-FOURTEENTH AMENDMENT-DISCRIMINATION IN SELECTION OF GRAND JURORS
Defendant\u27s conviction of murder was affirmed by the Texas Court of Criminal Appeals, which rejected defendant\u27s claim that discrimination in selection of the indicting grand jury had violated his constitutional rights. Defendant pointed out that the Negro proportion of grand jurors had uniformly been less than the ratio of Negroes to the total population of the county, and that on the past twenty-one lists the commissioners had consistently limited the number of Negroes to not more than one on each grand jury. On certiorari to the United States Supreme Court, held, reversed. Limitation of the number of Negroes on a grand jury to the approximate proportion of Negroes in the county eligible for grand jury service would constitute unconstitutional discrimination in violation of the rights of a member of that race against whom an indictment was returned by the grand jury so selected, since the accused is entitled to have charges against him considered by a grand jury in the selection of which there is neither inclusion nor exclusion because of race. Intentional exclusion proved by the statements of the commissioners that they chose for service only those whom they knew and that they knew no eligible Negroes was the actual discrimination on which the unconstitutionality was based. Cassell v. Texas, 339 U.S. 282, 70 S.Ct. 629 (1950)
CONSTITUTIONAL LAW-FREEDOM OF SPEECH
Defendant addressed a crowd of people, white and Negro, on a public sidewalk for the purpose of urging them to attend a certain meeting. During the course of his speech he \u27called Mayor Costello [of Syracuse] a champaign [sic] sipping bum and President Truman a bum. He referred to the American Legion as Nazi Gestapo agents-he also said the fifteenth Ward was run by corrupt politicians and that horse rooms were operating.\u27 He also appealed to the Negroes to rise up and fight for equal rights. The police were called but at first merely observed the gathering. Angry mutterings were heard as the crowd became divided in its sentiments toward the speaker. Pedestrians were unable to pass without going out into the street. Finally, after the police gave defendant several ineffective warnings to stop talking, he was arrested and convicted of disorderly conduct in violation of a state statute, over his objection that his freedom of speech had been unconstitutionally denied. On appeal to the New York Court of Appeals, held, affirmed. The constitutional guarantee of freedom of speech does not make this right absolute. Conviction for disorderly conduct does not infringe upon this right where the speaker on a public street encourages his audience to become divided into hostile camps, interferes with traffic, and deliberately agitates and goads the crowd and police officers into action. People v. Feiner, 300 N.Y. 391, 91 N.E. (2d) 316 (1950)
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