Optimisation of nickel electrodeposition solutions for power usage

If electroplating processes are to be truly ‘green’ a number of issues must be addressed, notably water and electrical power usage. Electricity is used both for the driving of the process itself and for some of the process conditions, eg. temperature, agitation etc. The study of solution conductivity for electroplating solutions shows how some electrical power saving can be achieved. In the case of nickel small gains can be made by optimising solution concentrations but greater gains are attainable by the use of air-free agitation

Interaction between electronic structure and strain in Bi nanolines on Si(001)

Heteroepitaxial strain can be a controlling factor in the lateral dimensions of 1-D nanostructures. Bi nanolines on Si(001) have an atomic structure which involves a large sub-surface reconstruction, resulting in a strong elastic coupling to the surrounding silicon. We present variable-bias STM and first principles electronic structure calculations of the Bi nanolines, which investigates this interaction. We show that the strain associated with the nanolines affects the atomic and electronic structure of at least two neighbouring Si dimers, and identify the mechanism behind this. We also present partial charge densities (projected by energy) for the nanoline with clean and hydrogenated surroundings and contrast it to the clean Si(001) surface.Comment: 10 pages, 3 figures, submitted to Surface Scienc

Interstitials, Vacancies and Dislocations in Flux-Line Lattices: A Theory of Vortex Crystals, Supersolids and Liquids

We study a three dimensional Abrikosov vortex lattice in the presence of an equilibrium concentration of vacancy, interstitial and dislocation loops. Vacancies and interstitials renormalize the long-wavelength bulk and tilt elastic moduli. Dislocation loops lead to the vanishing of the long-wavelength shear modulus. The coupling to vacancies and interstitials - which are always present in the liquid state - allows dislocations to relax stresses by climbing out of their glide plane. Surprisingly, this mechanism does not yield any further independent renormalization of the tilt and compressional moduli at long wavelengths. The long wavelength properties of the resulting state are formally identical to that of the ``flux-line hexatic'' that is a candidate ``normal'' hexatically ordered vortex liquid state.Comment: 21 RevTeX pgs, 7 eps figures uuencoded; corrected typos, published versio

Fault-Tolerant Aggregation: Flow-Updating Meets Mass-Distribution

Flow-Updating (FU) is a fault-tolerant technique that has proved to be efficient in practice for the distributed computation of aggregate functions in communication networks where individual processors do not have access to global information. Previous distributed aggregation protocols, based on repeated sharing of input values (or mass) among processors, sometimes called Mass-Distribution (MD) protocols, are not resilient to communication failures (or message loss) because such failures yield a loss of mass. In this paper, we present a protocol which we call Mass-Distribution with Flow-Updating (MDFU). We obtain MDFU by applying FU techniques to classic MD. We analyze the convergence time of MDFU showing that stochastic message loss produces low overhead. This is the first convergence proof of an FU-based algorithm. We evaluate MDFU experimentally, comparing it with previous MD and FU protocols, and verifying the behavior predicted by the analysis. Finally, given that MDFU incurs a fixed deviation proportional to the message-loss rate, we adjust the accuracy of MDFU heuristically in a new protocol called MDFU with Linear Prediction (MDFU-LP). The evaluation shows that both MDFU and MDFU-LP behave very well in practice, even under high rates of message loss and even changing the input values dynamically.Comment: 18 pages, 5 figures, To appear in OPODIS 201

Parsimonious Kernel Fisher Discrimination

By applying recent results in optimization transfer, a new algorithm for kernel Fisher Discriminant Analysis is provided that makes use of a non-smooth penalty on the coefficients to provide a parsimonious solution. The algorithm is simple, easily programmed and is shown to perform as well as or better than a number of leading machine learning algorithms on a substantial benchmark. It is then applied to a set of extreme small-sample-size problems in virtual screening where it is found to be less accurate than a currently leading approach but is still comparable in a number of cases

BRST Treatment of the Bohr Collective Hamiltonian at High Spins

The BRST treatment of triaxial systems rotating at high spins is used to solve perturbatively the $\gamma$-independent Bohr collective hamiltonian.Comment: 10 pages in LaTeX using Esp-LaTeX and Feynman package

Superconducting Coherence and the Helicity Modulus in Vortex Line Models

We show how commonly used models for vortex lines in three dimensional superconductors can be modified to include k=0 excitations. We construct a formula for the k=0 helicity modulus in terms of fluctuations in the projected area of vortex loops. This gives a convenient criterion for the presence of superconducting coherence. We also present Monte Carlo simulations of a continuum vortex line model for the melting of the Abrikosov vortex lattice in pure YBCO.Comment: 4 pages RevTeX, 2 eps figures included using eps

Synergistic therapeutic effect of arsenic trioxide and radiotherapy in BALB/C nude mice bearing nasopharyngeal carcinoma xenografts

It has been shown that arsenic trioxide (ATO) induced apoptosis in human nasopharyngeal carcinoma cells and inhibited the growth of nasopharyngeal carcinoma xenografts (NPCX) in nude mice. Aim: The present study was designed to determine whether ATO at the non-toxic dose level could potentiate the therapeutic effectiveness of radiation therapy in nasopharyngeal carcinoma, using a BALB/C nude mouse xenograft model. Methods: The mice bearing NPCX were treated with radiation alone (2, 4, and 6 Gy), ATO alone (4 mg/kg/day x 6 days), and ATO plus radiation at the same dosage levels. Time of tumor growth delay (defined as the time necessary for the tumor to grow four-fold of its initial volume after, compared with untreated tumors) and toxic effects were determined. Results: The low dose ATO alone has no pronounced effects on tumor growth delay compared to untreated control. However, compared with radiation alone, the combined regimen delayed the tumor growth by 2–10 days and had no significant toxic effects such as the liver function damage. Conclusions: Combination of ATO at non-toxic dose level and radiation has synergistic effects on tumor growth inhibition in vivo and is well tolerated.Установлено, что триоксид мышьяка (ТОМ) индуцирует апоптоз в клетках карциномы носоглотки человека и ингибирует рост ксенографта карциномы носоглотки у атимических мышей. Цель работы — установить терапевтическую эффективность радиотерапии в комбинации ТОМ в нетоксичной дозе мышам линии BALB/ с ксенографтом карциномы носоглотки. Методы: животные с ксенографтом карциномы носоглотки получали либо только радиотерапию (2, 4 и 6 Гр) или ТОМ (4 мг/кг/день в течение 6 дней), или их комбинацию в тех же режимах и дозах. Задержку роста опухоли определяли как различие во времени, необходимом для достижения опухолью 4-кратного объема по сравнению с начальным объемом в опытной группе versus такового в контрольной группе. Результаты: введение ТОМ в низкой дозе не оказывало выраженного влияния на рост опухоли по сравнению с показателями в конт­рольной группе, а в комбинации с облучением приводило к задержке роста опухоли на 2–12 сут по сравнению с показателями у животных, получавших только лучевую терапию при отсутствии выраженных побочных эффектов. Выводы: комбинация ТОМ в нетоксической дозе и лучевой терапии приводит к ингибированию роста опухоли in vivo и не вызывает побочных эффектов. Ключевые слова: триоксид мышьяка, радиотерапия, ксенографт карциномы носоглотки

Improved effective mobility extraction in MOSFETs

The standard method of extracting carrier effective mobility from electrical measurements on MOSFETs is reviewed and the assumptions implicit in this method are discussed. A novel technique is suggested that corrects for the difference in drain bias during IV and CV measurements. It is further shown that the lateral field and diffusion corrections, which are both commonly neglected, in fact cancel. The effectiveness of the proposed technique is demonstrated by application to data measured on a quasi-planar SOI finFET at 300 K and 4 K

Closed string tachyons, flips and conifolds

Following the analysis of tachyons and orbifold flips described in hep-th/0412337, we study nonsupersymmetric analogs of the supersymmetric conifold singularity and show using their toric geometry description that they are nonsupersymmetric orbifolds of the latter. Using linear sigma models, we see that these are unstable to localized closed string tachyon condensation and exhibit flip transitions between their two small resolutions (involving 2-cycles), in the process mediating mild dynamical topology change. Our analysis shows that the structure of these nonsupersymmetric conifolds as quotients of the supersymmetric conifold obstructs the 3-cycle deformation of such singularities, suggesting that these nonsupersymmetric conifolds decay by evolving towards their stable small resolutions.Comment: Latex, 22 pgs, 2 figs. v4: matches JHEP version, 29 pgs, 3 figures, more elaborate Introduction, various clarifications adde