The Lutheran Doctrine of the Autopistia of Holy Scripture

This doctrine of classical Lutheran theology is becoming very important today in connection with the discussion of the authority of Scripture and the Confessions. Stated briefly its immediate scope in its formal aspect is that Holy Scripture requires no other argument to prove itself the inerrant divine truth than the evidence which it bears within itself and with which it confronts the Church and the individual as the living Word of the living God, that is to say, as the Word which has life in itself and awakens life

Food Habits and Ecology of Beavers in Southeastern Virginia

The food habits and ecology of three beaver colonies in James County, Virginia were studied. Vegetation surrounding the colonies was characterized as southern mixed hardwood forest or lowland swamp forest. Stream flow values ranged from 0.013 to 0.369 m3/sec. Water depth ranged from 0.5 60 4.0 m. Caloric value of 13 heavily used woody species ranged from 3305 to 6204 cal/g. Considerable seasonal variation was noted in most species with the lowest caloric values noted in summer. No relationship was found between caloric value and frequency of use. Fresh cutting was monitored on a weekly basis and a daily tally was made of all cut stumps. Alder, tulip poplar, red maple, white oak, bayberry, dogwood, pine, ironwood, viburnum, beech, and spicebush were heavily used. The latter three species have not been previously reported in the literature as food for beavers. Beaver were found to be active year-round, building an extensive food cache but using it only lightly

Using Quasiparticle Poisoning To Detect Photons

According to a proposal, a phenomenon associated with excitation of quasiparticles in certain superconducting quantum devices would be exploited as a means of detecting photons with exquisite sensitivity. The phenomenon could also be exploited to perform medium-resolution spectroscopy. The proposal was inspired by the observation that Coulomb blockade devices upon which some quantum logic gates are based are extremely sensitive to quasiparticles excited above the superconducting gaps in their leads. The presence of quasiparticles in the leads can be easily detected via the charge states. If quasiparticles could be generated in the leads by absorption of photons, then the devices could be used as very sensitive detectors of electromagnetic radiation over the spectral range from x-rays to submillimeter waves. The devices in question are single-Cooper-pair boxes (SCBs), which are mesoscopic superconducting devices developed for quantum computing. An SCB consists of a small superconducting island connected to a reservoir via a small tunnel junction and connected to a voltage source through a gate capacitor. An SCB is an artificial two-level quantum system, the Hamiltonian of which can be controlled by the gate voltage. One measures the expected value of the charge of the eigenvectors of this quantum system by use of a radio-frequency single-electron transistor. A plot of this expected value of charge as a function of gate voltage resembles a staircase that, in the ideal case, consists of steps of height 2 e (where e is the charge of one electron). Experiments have shown that depending on the parameters of the device, quasiparticles in the form of "broken" Cooper pairs present in the reservoir can tunnel to the island, giving rise to steps of 1 e. This effect is sometimes called "poisoning." Simulations have shown that an extremely small average number of quasiparticles can generate a 1-e periodic signal. In a device according to the proposal, this poisoning would be turned to advantage. Depending on the wavelength, an antenna or other component would be used to couple radiation into the reservoir, wherein the absorption of photons would break Cooper pairs, thereby creating quasiparticles that, in turn, would tunnel to the island, creating a 1-e signal. On the basis of conservative estimates of device parameters derived from experimental data and computational simulations that fit the data, it has been estimated that the noise equivalent power of a device according to the proposal could be as low as 6 10(exp -22) W/Hz(exp 1/2). It has also been estimated that the spectroscopic resolution (photon energy divided by increment of photon energy) of such a device in visible light would exceed 100

Kinetics of non-equilibrium quasiparticle tunneling in superconducting charge qubits

We directly observe low-temperature non-equilibrium quasiparticle tunneling in a pair of charge qubits based on the single Cooper-pair box. We measure even- and odd-state dwell time distributions as a function of temperature, and interpret these results using a kinetic theory. While the even-state lifetime is exponentially distributed, the odd-state distribution is more heavily weighted to short times, implying that odd-to-even tunnel events are not described by a homogenous Poisson process. The mean odd-state dwell time increases sharply at low temperature, which is consistent with quasiparticles tunneling out of the island before reaching thermal equilibrium.Comment: Replaced Figure 1 with color version, corrected more typos. Version submitted to PR

Parametric Amplification and Back-Action Noise Squeezing by a Qubit-Coupled Nanoresonator

We demonstrate the parametric amplification and noise squeezing of nanomechanical motion utilizing dispersive coupling to a Cooper-pair box qubit. By modulating the qubit bias and resulting mechanical resonance shift, we achieve gain of 30 dB and noise squeezing of 4 dB. This qubit-mediated effect is 3000 times more effective than that resulting from the weak nonlinearity of capacitance to a nearby electrode. This technique may be used to prepare nanomechanical squeezed states

Programmable networks for quantum algorithms

The implementation of a quantum computer requires the realization of a large number of N-qubit unitary operations which represent the possible oracles or which are part of the quantum algorithm. Until now there are no standard ways to uniformly generate whole classes of N-qubit gates. We have developed a method to generate arbitrary controlled phase shift operations with a single network of one-qubit and two-qubit operations. This kind of network can be adapted to various physical implementations of quantum computing and is suitable to realize the Deutsch-Jozsa algorithm as well as Grover's search algorithm.Comment: 4 pages. Accepted version; Journal-ref. adde

Test-Retest Reliability and Construct Validity of the Tinetti Performance-Oriented Mobility Assessment in People With Stroke

Background and Purpose: The Tinetti Performance-Oriented Mobility Assessment (POMA) is commonly used to measure balance ability in older adults. The purpose of this study was to determine the test-retest reliability and minimal detectable change (MDC) of the POMA and explore its cross-sectional and longitudinal construct validity for use in people early after stroke. Methods: Participants were recruited if they had a first documented stroke and were receiving physical therapy during inpatient rehabilitation. The POMA, gait speed, and motor Functional Independence Measure (FIM) scores were collected at admission and at discharge from inpatient rehabilitation. A second trial of the POMA was conducted 1 day after the first trial for reliability analysis. Correlations (Spearman rho) between raw scores of admission and discharge outcome measures, as well as change in scores between admission and discharge, were used to explore the construct validity of the POMA. Results: Fifty-five people, with average age of 75 ± 11 years, who had experienced first documented stroke participated in the study and began inpatient physical therapy at a mean of 8 ± 5 days poststroke. Test-retest reliability intraclass correlation coefficient (ICC2,1) was 0.84 and MDC was 6 points. The POMA scores were moderately correlated to motor FIM and gait speed scores at admission (rs = 0.55 and 0.70) and discharge (rs = 0.55 and 0.82.) Change scores of all 3 measures had a fair correlation (rs = 0.28-0.51). Discussion and Conclusions: Test-retest reliability and MDC of the POMA in people with stroke is similar to previous research in older adult long-term care residents. Results support cross-sectional and longitudinal construct validity of the POMA in persons early after stroke and demonstrate validity and reliability to measure balance ability in this population

Characterization of a Differential Radio-Frequency Single-Electron Transistor

We have fabricated and characterized a new type of electrometer that couples two parallel single-electron transistors (SETs) to a radio-frequency tank circuit for use as a differential RF-SET. We demonstrate operation of this device in summing, differential, and single-SET operation modes, and use it to measure a Coulomb staircase from a differential single Cooper-pair box. In differential mode, the device is sensitive to uncorrelated input signals while screening out correlated ones.Comment: 3 pages, 3 figures, submitted to Applied Physics Letter