Computation of mutual entropy in quantum markov chains

There are several damping phenomena in quantum optics. Such phenomena have been usually explained by open systems. In statistical physics, open system dynamics have been used to study the irreversibility and the approach to equilibrium. In this paper, the dynamical change of the mutual entropy for an open system, frequently studied in the quantum optics literature, is rigorously computed through a model of quantum Markov chain. In particular, the concrete formula of Stinespring expression for such a model is obtained and applied to the derivation of the mutual entropy, and some computational results are presented.     

The TDS: a new device for comparing active and passive-guided touch.

A problem when comparing active and passive tactile perception of two-dimensional (2-D) stimuli is matching the active and passive tasks on all variables except the one of interest--active versus passive touch. A new computer-controlled device--the tactile display system (TDS)--has been developed to deal with this problem. The TDS tracks an "active" subject's fingertip movements during exploration of a raised line drawing and digitally records this spatio-temporal information. It then guides a passive participant's fingertip over the same path, matching for location and speed. Any difference in performance can thus be attributed to the different conditions (active versus passive) because other variables are held constant.     

Characterization of Toscana virus-defective interfering particles generated in vivo

Adenylate kinase (AK), which catalyzes the equilibrium reaction among AMP, ADP, and ATP, is considered to participate in the homeostasis of energy metabolism in cells. Among three vertebrate isozymes, AK isozyme 1 (AK1) is present prominently in the cytosol of skeletal muscle and brain. When mouse embryonal carcinoma P19 cells were differentiated by retinoic acid into neural cells, the amount of AK1 protein and enzyme activity increased about fivefold concomitantly with neurofilament (NF). Double-immunofluorescence staining showed that both AK1 and NF were located in neuronal processes as well as the perinuclear regions in neuron-like cells, but not in glia-like cells. The amount of brain-type creatine kinase increased only twofold during P19 differentiation. The AK isozyme 2, which was not detected in adult mouse brain, was found in P19 cells and did not increase during the differentiation. Mitochondrial AK isozyme 3, which uses GTP instead of ATP as a phosphate donor, was increased significantly. Immunohistochemical analysis with the primary cultured cells from rat cerebral cortex showed similar cellular localization of AK1 to those observed with differentiated P19 cells. These results suggest an important role of this enzyme in neuronal functions and in neuronal differentiation.     

Carcinoembryonic antigen (CEA), tissue polypeptide antigen (TPA) and other prognostic indicators in squamous cell lung cancer

Multivariate models of survival have been established for both small cell and non-small cell lung cancers. So far, no study has focussed on squamous cell types. Previous demonstrations of the prognostic value of the tissue polypeptide antigen (TPA) and, partially, of the carcinoembryonic antigen (CEA) are based on univariate analyses of survival. These analyses do not account for the other prognostic factors. In the present study, we report the combined influence of various clinical and biological characteristics on the survival duration of 360 patients with a newly diagnosed squamous cell carcinoma of the lung. The study comprised 29 variables, including age, sex, smoking habit (SH), symptoms at diagnosis, the Karnofsky performance status (KPS), weight loss (WL), radiological findings, various disease extent parameters (DEP), CEA and TPA. Preliminary univariate analyses showed that 20 variables were survival-related. The Cox proportional hazards regression analysis selected stage of disease, KPS, TPA, WL, the existence of bone metastases, and SH as independent factors of prognosis (global chi-square: 122.40, P = 0.0000). A second multivariate analysis, performed with the same covariates but excluding DEP, revealed previous pulmonary diseases and CEA to be, in addition to KPS, TPA, SH, and WL the next most influential prognostic determinants. Also in squamous cell lung cancer, classifications based on the Cox's prediction equation may improve individual counseling and patient selection for therapeutic trials. In this malignancy, TPA shows an independent and strong prognostic significance while CEA shares informations of diverse other prognostic factors and seems to be less important.     

Targeting Human Papillomavirus-Associated Cancer by Oncoprotein-Specific Recombinant Antibodies

In recent decades, recombinant antibodies against specific antigens have shown great promise for the therapy of infectious diseases and cancer. Human papillomaviruses (HPVs) are involved in the development of around 5% of all human cancers and HPV16 is the high-risk genotype with the highest prevalence worldwide, playing a dominant role in all HPV-associated cancers. Here, we describe the main biological activities of the HPV16 E6, E7, and E5 oncoproteins, which are involved in the subversion of important regulatory pathways directly associated with all known hallmarks of cancer. We then review the state of art of the recombinant antibodies targeted to HPV oncoproteins developed so far in different formats, and outline their mechanisms of action. We describe the advantages of a possible antibody-based therapy against the HPV-associated lesions and discuss the critical issue of delivery to tumour cells, which must be addressed in order to achieve the desired translation of the antibodies from the laboratory to the clinic.     

High levels of the mitochondrial large ribosomal subunit protein 40 prevent loss of mitochondrial DNA in null mmf1 Saccharomyces cerevisiae cells

Members of the YERO57c/YJGFc/UK114 protein family have been identified in bacteria and eukaryotes. The budding yeast Saccharomyces cerevisiae contains two different proteins of this family, Hmf1p and Mmf1p. We have previously shown that Mmf1p is a mitochondrial protein functionally related to its human homologue and able to influence the maintenance of mitochondrial DNA. Deletion of Mmf1 results in loss of the mitochondrial genome. Using a multicopy suppression approach, we have identified a protein of the mitochondrial large ribosomal subunit, MRPL40, which stabilizes mtDNA in Deltammf1 cells. Overexpression of MRPL40 did not prevent loss of mtDNA in a mutant strain lacking the mitochondrial protein Abf2p. Thus, MRPL40 does not have a general effect on mtDNA stability, but it may be specific for the mmf1-null strain. We also show that the Deltamrpl40 cells present a similar phenotype to the mmf1-null strain, having reduced mtDNA stability and growth rate. Furthermore, we observed that rho(+)Deltamrpl40 haploid cells can be obtained when tetrads are directly dissected on medium containing a non-fermentable carbon source. Thus, replication and segregation of the mtDNA can occur in the absence of MRPL40. We also show that another mitochondrial ribosomal protein, MRPL38, is able to overcome the Deltammf1-associated defect. Together, our results suggest a link between Mmf1p and the two mitochondrial ribosomal proteins.     

Mean Quantum Sojourn Time

This article introduces the notion of Mean Quantum Sojourn Time for a Quantum Dynamical Semigroup acting over an arbitrary von Neumann algebra. This notion is used to analyze the asymptotic behaviour of the underlying dynamics and allows one to include, as a particular case, earlier classification of states obtained in scattering theory. Furthermore, certain connections with convergence towards an equilibrium, as well as with spectral-type measures, are studied.     

Control of Quantum Langevin Equations

The problem of controlling quantum stochastic evolutions arises naturally in several different fields such as quantum chemistry, quantum information theory, quantum engineering, etc. In this paper, we apply the recently discovered closed form of the unitarity conditions for stochastic evolutions driven by the square of white noise [9] to solve this problem in the case of quadratic cost functionals (cf. (5.5) below). The optimal control is explicitly given in terms of the solution of an operator Riccati equation. Under general conditions on the system Hamiltonian part of the stochastic evolution and on the system observable to be controlled, this equation admits solutions with the required properties and they can be explicitly described.     

Accessibility of lithium cations in high-silica zeolites investigated using the NMR paramagnetic shift effect of adsorbed oxygen

The accessibility of lithium cations in the high-silica zeolites ZSM-5 and beta was investigated using ⁷Li MAS NMR spectroscopy. The samples are investigated in vacuum and in the presence of adsorbed oxygen molecules. The paramagnetic shift effect due to the oxygen molecules was exploited to determine the fractions of accessible lithium cations. Approximately 85% of lithium cations in Al-ZSM-5 (Si/Al=50) are accessible to oxygen molecules, while none of the cation sites in zeolite Al-beta (Si/Al=18 and 8) and only a small fraction in B-beta (Si/B=15) were available for adsorption. This difference indicates a very distinct coordination environment for Li⁺ in zeolite beta as compared to ZSM-5.     

Evaluation of a Cu/YSZ and Ni/YSZ Bilayer Anode for the Direct Utilization of Methane in a Solid‐Oxide Fuel Cell

Carbon deposition is an issue when operating solid oxide fuel cells (SOFC) on fuels other than hydrogen, and so a variety of strategies have been used to prevent carbon accumulation on the anodes. In this paper, we describe a bilayer anode that contains a functional layer consisting of Ni/YSZ and a conduction layer consisting of Cu/YSZ. The anode‐supported button cells were fabricated using a uni‐axially pressing technique to produce the anode, followed by impregnation with Cu. The cells were tested at 1,023 K in dry CH₄ and their performance compared to that of a typical Ni/YSZ anode. The Cu does not catalyze the cracking of methane and as such less carbon deposits in the conduction layer resulting in anode stability for over 100 h. The limitation with using Cu in the anode is the temperature of operation.