Macroscopic proof of the Jarzynski-Wojcik fluctuation theorem for heat exchange

In a recent work, Jarzynski and Wojcik (2004 Phys. Rev. Lett. 92, 230602) have shown by using the properties of Hamiltonian dynamics and a statistical mechanical consideration that, through contact, heat exchange between two systems initially prepared at different temperatures obeys a fluctuation theorem. Here, another proof is presented, in which only macroscopic thermodynamic quantities are employed. The detailed balance condition is found to play an essential role. As a result, the theorem is found to hold under very general conditions.Comment: 9 pages, 0 figure

Thermodynamic processes generated by a class of completely positive quantum operations

An attempt toward the operational formulation of quantum thermodynamics is made by employing the recently proposed operations forming positive operator-valued measures for generating thermodynamic processes. The quantity of heat as well as the von Neumann entropy monotonically increases under the operations. The fixed point analysis shows that repeated applications of these operations to a given system transform from its pure ground state at zero temperature to the completely random state in the high temperature limit with intermediate states being generically out of equilibrium. It is shown that the Clausius inequality can be violated along the processes, in general. A bipartite spin-1/2 system is analyzed as an explicit example.Comment: 22 pages and 1 figure. Modern Physics Letters B, in pres

The Wiedemann Effect of the Magnetostriction Alloy "Alfer" at High Temperatures

The Wiedemann effect of "Alfer" (12.91 per cent Al-Fe alloy) was measured with the annealed specimen at high temperatures. As the temperature rises, the effect gradually decreases at the constant current through the specimen, and also the higher the temperature is, the weaker the field is for the maximum effect. When the current through the specimen as well as the longitudinal field is constant, the effect gradually decreases with the rise of temperature, and bcecomes extremely small at the magnetic transformation point of the Fe_3Al superlattice, and vanishes at the magnetic transformation point of α phase. The effect of Ni and Fe was measured to compare with that of Alfer. The temperature dependence of the effect of Ni is similar to that of Alfer, but that of Fe is different from both, that is, it gradually increases as the temperature rises, and after reaching a maximum at about 600℃, rapidly decreases, becoming zero at the magnetic transformation point

Reproducibility of CBF using pCASL

Purpose : To determine the reproducibility of corrected quantitative cerebral blood flow (qCBF) through measurement of transit flow time using multi-delay three-dimensional pseudo-continuous arterial spin labeling (pCASL) in healthy men and women and to evaluate the differences in qCBF between not only men and women, but also the follicular and luteal phases of the women’s menstrual cycle. Methods : The participants were 16 healthy volunteers (8 men and 8 women ; mean age, 25.3 years). Two MRI were conducted for all participants ; female participants were conducted in the follicular and luteal phases. The reproducibility of qCBF values was evaluated by the intraclass correlation coefficient (ICC) and differences between the two groups were estimated by voxel-based morphometry (VBM) analysis. Results : The qCBF values were lower in men than in women, and those in females were significantly different between the follicular and luteal phases (P < 0.05). In VBM analysis, the qCBF values of the lower frontal lobes were significantly higher in women than in men (P < 0.05). The qCBF values of the frontal pole were significantly higher in the follicular phase than in the luteal phase (P < 0.01). Conclusion : Multi-delay pCASL can reveal physiological and sex differences in cerebral perfusion

Evaluation of Patient Positioning during Digital Tomosynthesis and Reconstruction Algorithms for Ilizarov Frames: A Phantom Study

Aim: Metallic components from circular external fixators, including the Ilizarov frame, cause artefacts on X-rays and obstruct clear visualisation of bone detail. We evaluated the ability of tomosynthesis to reduce interference on radiographs caused by metal artefacts and developed an optimal image acquisition method for such cases. Materials and methods: An Ilizarov frame phantom was constructed using rods placed on the bone for the purpose to evaluate the benefits of tomosynthesis. Distances between the rod and bone and the angle between the rod and X-ray tube orbit were set at three different levels. Filtered backprojection images were reconstructed using two different features of the reconstruction function: THICKNESS−− (CONTRAST4) and THICKNESS++ (METAL4); the first is suitable for improving contrast and the second is suitable for metal artefacts. The peak signal-to-noise ratio (PSNR) was used during image evaluation to determine the influence of the metallic rod on bone structure visibility. Results: The PSNR increased as the angle between the metal rod and the X-ray tube orbit and the distance between the metallic rod and bone increased. The PSNR was larger when using THICKNESS−− (CONTRAST4) than when using THICKNESS++ (METAL4). Conclusion: The optimal reconstruction function and image acquisition determined using the metallic rod in this study suggest that quality equal to that without the metallic rod can be obtained. Clinical significance: We describe an optimised method for image acquisition without unnecessary acquisition repetition and unreasonable posture changes when the bone cannot be adequately visualised

Process time and cost savings achieved through automation and islands of integration in existing facilities.

For most biopharmaceutical manufacturers the cost, time and quality improvements offered by adopting continuous manufacturing operations is, as with any new technology, inhibited by the research and validation costs associated with early adoption. Additional effort is needed to validate the novel technology in-house. There are simple changes that can be made in disposable biomanufacturing , which are necessary for the eventual adoption of full continuous operations, and yet have benefits now. These step changes are shown by economic & scheduling models to offer direct cost savings and improved facility throughput. A road map of these step-wise improvements is provided that leads to fully continuous processing, but minimises the technological risk. The first step change is a wider adoption of process automation. Automation eliminates operator error, reduces contamination risk and improves batch-batch quality. The higher direct cost of the operating system is offset by improved utilisation of facilities and fewer batch failures. The next step is to automate the operation of a combination of relatively simple units, such as dead-end filtration, flow-through adsorption, virus filtration, in-line concentration. The aim is to minimise hold steps, QC testing, processing time and maximise the use of disposable manifolds. Incorporating automated integrity testing into the operation further enhances the processing. Examples of such operating systems will be described, either as standard items that require configuration or as customised options, to illustrate the economic risk/benefit analysis. Additionally, the islands of continuous operation can be extended - for example, perfusion bioreactor operation, capture chromatography integrated with low pH virus inactivation, or flowthrough polishing chromatography integrated with virus filtration and diafiltration. Integrated chromatography and virus inactivation will be reported with the main advantages seen from contracting the process from two working shifts to one and yield increase when producing biotherapeutics sensitive to low pH or sensitive to changes in pH through the isoelectric point. How each step change compares to envisioned full continuous processing depends on the operating requirements of the facility, with the key variables being the number of biopharmaceutical products manufactured, number of batches per product, titre, bioreactor volume, changeover time and QA release time. As with all facility and operational changes, the value of the benefits discussed depends on the demand being placed on the facilities by products in clinical phases or commercial manufacturin