A study of electrochemical processes in silver-cadmium secondary cells

Electrochemical processes in silver-cadmium secondary cell

Shot noise limited heterodyne detection of CARS signals

We demonstrate heterodyne detection of CARS signals using a cascaded phase-preserving chain to generate the\ud CARS input wavelengths and a coherent local oscillator. The heterodyne ampli¯cation by the local oscillator re-\ud veals a window for shot noise limited detection before the signal-to-noise is limited by amplitude °uctuations. We\ud demonstrate an improvement in sensitivity by more than 3 orders of magnitude for detection using a photodiode.\ud This will enable CARS microscopy to reveal concentrations below the current mMolar range

Visualisation Tools for Multi-Perspective, Cross-Sector, Long-Term Infrastructure Performance Evaluation

Across different infrastructure sectors there are systems that help to monitor the current and near-future operation and performance of a particular system. Whilst Supervisory Control and Data Acquisition (SCADA) systems are critical to maintaining acceptable levels of functionality, they do not provide insights over the longer timescales across which strategic investment decisions play out. To understand how individual or multiple, interdependent, infrastructure sectors perform over longer timescales, capacity/demand modelling is required. However, the outputs of such models are often a complex high-dimensionality result-set, and this complexity is further compounded when crosssector evaluation is required. To maximise utility of such models, tools are required that can process and present key outputs. In this paper we describe the development of prototype tools for infrastructure performance evaluation in relation to different strategic decisions and the complex outputs generated from capacity and demand models of five infrastructure sectors (energy, water, waste water, solid waste, transport) investigated within the UK Infrastructure Transitions Research Consortium (ITRC). By constructing tools that expose various dimensions of the model outputs, a user is able to take greater control over the knowledge discovery process

Little Higgs Model Completed with a Chiral Fermionic Sector

The implementation of the little Higgs mechanism to solve the hierarchy problem provides an interesting guiding principle to build particle physics models beyond the electroweak scale. Most model building works, however, pay not much attention to the fermionic sector. Through a case example, we illustrate how a complete and consistent fermionic sector of the TeV effective field theory may actually be largely dictated by the gauge structure of the model. The completed fermionic sector has specific flavor physics structure, and many phenomenological constraints on the model can thus be obtained beyond gauge, Higgs, and top physics. We take a first look on some of the quark sector constraints.Comment: 14 revtex pages with no figure, largely a re-written version of hep-ph/0307250 with elaboration on flavor sector FCNC constraints; accepted for publication in Phys.Rev.

Topological interactions in systems of mutually interlinked polymer rings

The topological interaction arising in interlinked polymeric rings such as DNA catenanes is considered. More specifically, the free energy for a pair of linked random walk rings is derived where the distance $R$ between two segments each of which is part of a different ring is kept constant. The topology conservation is imposed by the Gauss invariant. A previous approach (M.Otto, T.A. Vilgis, Phys.Rev.Lett. {\bf 80}, 881 (1998)) to the problem is refined in several ways. It is confirmed, that asymptotically, i.e. for large $R\gg R_G$ where $R_G$ is average size of single random walk ring, the effective topological interaction (free energy) scales $\propto R^4$.Comment: 16 pages, 3 figur

In vitro evidence for senescent multinucleated melanocytes as a source for tumor-initiating cells

Oncogenic signaling in melanocytes results in oncogene-induced senescence (OIS), a stable cell-cycle arrest frequently characterized by a bi- or multinuclear phenotype that is considered as a barrier to cancer progression. However, the long-sustained conviction that senescence is a truly irreversible process has recently been challenged. Still, it is not known whether cells driven into OIS can progress to cancer and thereby pose a potential threat. Here, we show that prolonged expression of the melanoma oncogene N-RAS61K in pigment cells overcomes OIS by triggering the emergence of tumor-initiating mononucleated stem-like cells from senescent cells. This progeny is dedifferentiated, highly proliferative, anoikis-resistant and induces fast growing, metastatic tumors. Our data describe that differentiated cells, which are driven into senescence by an oncogene, use this senescence state as trigger for tumor transformation, giving rise to highly aggressive tumor-initiating cells. These observations provide the first experimental in vitro evidence for the evasion of OIS on the cellular level and ensuing transformation

Infective endocarditis, 1983–1988: Echocardiographic findings and factors influencing morbidity and mortality

The echocardiograms and clinical records of 70 patients with infective endocarditis seen between 1983 and 1988 were examined to evaluate the role of two-dimensional and Doppler echocardiography in the diagnosis of infective endocarditis and identify risk factors for morbidity and mortality. A blinded observer reviewed the echocardiograms for the presence and size of vegetations and the severity of the valvular regurgitation. Vegetations were identified in 54 (78%) of 69 technically satisfactory echocardiograms. In 38 patients whose heart was examined at surgery or autopsy, all vegetations diagnosed by echocardiography were confirmed, but six additional vegetations were found.Abnormal (≥2+) valvular regurgitation was present in 88% of patients. No patient with ≤1+ regurgitation (n = 8) died or required valve surgery for heart failure, but three of the eight patients did undergo surgery for mycotic aneurysm, recurrent embolism or paravalvular abscess. In patients without embolism before echocardiography, there was a trend toward a greater incidence of subsequent embolism in those with vegetations >10 mm in size (26% [8 of 31] compared with 11% [2 of 18] with vegetations ≤10 mm) (p = 0.19). By multivariate analysis, risk factors for in-hospital death (n = 7) were an infected prosthetic valve (p < 0.007), systemic embolism (p < 0.02) and infection with Staphylococcus aureus(p = 0.05).It is concluded that 1) if valvular regurgitation is ≤1+, the risk of in-hospital death is low, and progression to cardiac surgery for hemodynamic instability is unlikely; 2) there is a trend toward a higher risk of embolization in patients with vegetations >10 mm in size; 3) early mortality now relates to infected prosthetic heart valves, embolism and Staphylococcus aureus; and 4) when a paravalvular abscess or prosthetic valve endocarditis is suspected, transthoracic echocardiographic findings are often equivocal and transesophageal echocardiography may be of benefit

Analytical study of the effect of recombination on evolution via DNA shuffling

We investigate a multi-locus evolutionary model which is based on the DNA shuffling protocol widely applied in \textit{in vitro} directed evolution. This model incorporates selection, recombination and point mutations. The simplicity of the model allows us to obtain a full analytical treatment of both its dynamical and equilibrium properties, for the case of an infinite population. We also briefly discuss finite population size corrections

Process behavior and product quality in fertilizer manufacturing using continuous hopper transfer pan granulation—Experimental investigations

Fertilizers are commonly used to improve the soil quality in both conventional and organic agriculture. One such fertilizer is dolomite for which soil application in granulated form is advantageous. These granules are commonly produced from ground dolomite powder in continuous pan transfer granulators. During production, the granulator’s operation parameters affect the granules’ properties and thereby also the overall performance of the fertilizer. To ensure product granules of certain specifications and an efficient overall production, process control and intensification approaches based on mathematical models can be applied. However, the latter require high-quality quantitative experimental data describing the effects of process operation parameters on the granule properties. Therefore, in this article, such data is presented for a lab-scale experimental setup. Investigations were carried out into how variations in binder spray rate, binder composition, feed powder flow rate, pan inclination angle, and angular velocity affect particle size distribution, mechanical stability, and humidity. Furthermore, in contrast to existing work samples from both, pan granules and product granules are analyzed. The influence of operation parameter variations on the differences between both, also known as trajectory separation, is described quantitatively. The results obtained indicate an increase in the average particle size with increasing binder flow rate to feed rate and increasing binder concentration and the inclination angle of the pan. Compressive strength varied significantly depending on the operating parameters. Significant differences in properties were observed for the product and the intermediate (pan) samples. In fact, for some operation parameters, e.g., binder feed rate, the magnitude of the separation effect strongly depends on the specific value of the operation parameter. The presented concise data will enable future mathematical modeling of the pan granulation process, e.g., using the framework of population balance equations

The Power of Centralized PC Systems of Pushdown Automata

Parallel communicating systems of pushdown automata (PCPA) were introduced in (Csuhaj-Varj{\'u} et. al. 2000) and in their centralized variants shown to be able to simulate nondeterministic one-way multi-head pushdown automata. A claimed converse simulation for returning mode (Balan 2009) turned out to be incomplete (Otto 2012) and a language was suggested for separating these PCPA of degree two (number of pushdown automata) from nondeterministic one-way two-head pushdown automata. We show that the suggested language can be accepted by the latter computational model. We present a different example over a single letter alphabet indeed ruling out the possibility of a simulation between the models. The open question about the power of centralized PCPA working in returning mode is then settled by showing them to be universal. Since the construction is possible using systems of degree two, this also improves the previous bound three for generating all recursively enumerable languages. Finally PCPAs are restricted in such a way that a simulation by multi-head automata is possible