On a Perceived Expressive Inadequacy of Principia Mathematica

This paper deploys a Cantor-style diagonal argument which indicates that there is more possible mathematical content than there are propositional functions in Russell and Whitehead's Principia Mathematica and similar formal systems. This technical result raises a historical question: "How did Russell, who was himself an expert in diagonal arguments, not see this coming?" It turns out that answering this question requires an appreciation of Russell's understanding of what logic is, and how he construed the relationship between logic and Principia Mathematica

Effects of harvesting time on some yield and quality traits of different maturing potato cultivars

The effect of harvesting time was investigated on yield and quality traits for spring season production in different maturing potato (Solanum tuberosum L.) cultivars under agro-climatic conditions of southern of Turkey in 2006 and 2007. The experimental layout was a randomized split plot with three replications, including six potato cultivars as main plots and four harvesting times as subplots. The cultivars tested were adora (early), carrera (early), felsina (mid-early), marfona (mid-early), mondial (mid-late) and vangogh (mid-late). Samples of tubers were harvested at 75, 90, 105 and 120 days after planting (DAP) in spring crop. Early cultivars carrera and felsina gave more than 2 t ha-1 tuber yield at 120 DAP. However, vangogh and mondial (mid-late cultivars) proved to be superior cultivars in relation to dry matter, specific gravity or starch content at 105 DAP.Key words: Potato, harvesting time, cultivar, yield, quality

The self-consistent calculation of the edge states at quantum Hall effect (QHE) based Mach-Zehnder interferometers (MZI)

The spatial distribution of the incompressible edge states (IES) is obtained for a geometry which is topologically equivalent to an electronic Mach-Zehnder interferometer, taking into account the electron-electron interactions within a Hartree type self-consistent model. The magnetic field dependence of these IES is investigated and it is found that an interference pattern may be observed if two IES merge or come very close, near the quantum point contacts. Our calculations demonstrate that, being in a quantized Hall plateau does not guarantee observing the interference behavior.Comment: EP2DS-17 Proceedings, 6 Pages, 2 Figure

Trajectories of charged particles trapped in Earth's magnetic field

I outline the theory of relativistic charged-particle motion in the magnetosphere in a way suitable for undergraduate courses. I discuss particle and guiding center motion, derive the three adiabatic invariants associated with them, and present particle trajectories in a dipolar field. I provide twelve computational exercises that can be used as classroom assignments or for self-study. Two of the exercises, drift-shell bifurcation and Speiser orbits, are adapted from active magnetospheric research. The Python code provided in the supplement can be used to replicate the trajectories and can be easily extended for different field geometries.Comment: 10 pages, 7 figures. Submitted to American Journal of Physic

The Effect of Seawater Conductivity on the Treatment of Leachate by Electrocoagulation

The effect of seawater (SW) conductivity on the treatment of domestic solid waste leachates (DSWL) and hazardous solid waste leachates (HSWL) by means of EC was investigated. Seawater, which is a strong electrolyte with a rich content of ions, has been fed together with the leachates to the reactors with Fe and Al electrodes. In the experiments, the treatment was performed by mixing leachate (DSWL and HSWL) with seawater in the proportions of 1:1 and 1:3. The efficiency of the process was determined by observing such parameters of suspended solids as phosphate, sulphate, color and turbidity. It was determined that the removal efficiencies related to the amount of seawater added, increase for all parameters except sulphate ions removal. Obtained data showed the best removal efficiency for Fe and Al electrodes ranging from 67 % to 100 % in the phosphate content, color and turbidity. For suspended solids and sulfate ions, the removal efficiencies vary in the range of 50–70 %. The results show that seawater added to the process accelerates the EC process due to increasing conductivity and the presence of other ions in its composition

Towards Activity Context using Software Sensors

Service-Oriented Computing delivers the promise of configuring and reconfiguring software systems to address user's needs in a dynamic way. Context-aware computing promises to capture the user's needs and hence the requirements they have on systems. The marriage of both can deliver ad-hoc software solutions relevant to the user in the most current fashion. However, here it is a key to gather information on the users' activity (that is what they are doing). Traditionally any context sensing was conducted with hardware sensors. However, software can also play the same role and in some situations will be more useful to sense the activity of the user. Furthermore they can make use of the fact that Service-oriented systems exchange information through standard protocols. In this paper we discuss our proposed approach to sense the activity of the user making use of software

Traffic climate scale: Comparing samples from Turkey and Sweden

Traffic climate is a recent and one of the essential topics in traffic and transportation research. Various studies have examined the relations of traffic climate with driving outcomes such as accidents by using different versions of the Traffic Climate Scale (TCS). In a recent attempt, 16-items and 38-items versions of the TCS were examined in different countries. With respect to that, the present study aims to investigate the psychometric properties of 16-items and 38-items versions in samples from Turkey and Sweden and to test the traffic climate differences of these two countries. A total of 309 participants from Turkey and 357 participants from Sweden completed a questionnaire including a demographic information form and the TCS. Confirmatory factor analyses showed that the short TCS had better fit indexes with acceptable reliability. Moreover, the traffic system in Turkey was perceived to be more internally and externally demanding and less functional compared to the traffic system in Sweden. The results suggest that the short TCS is a reliable and user-friendly measurement to understand the perception of road users

Symplectic Symmetry of the Neutrino Mass and the See-Saw Mechanism

We investigate the algebraic structure of the most general neutrino mass Hamiltonian and place the see-saw mechanism in an algebraic framework. We show that this Hamiltonian can be written in terms of the generators of an Sp(4) algebra. The Pauli-Gursey transformation is an SU(2) rotation which is embedded in this Sp(4) group. This SU(2) also generates the see-saw mechanism.Comment: 11 pages, REVTE

L-MYC gene polymorphism and risk of thyroid cancer

L-myc gene polymorphism is a representative genetic trait responsible for an individual’s susceptibility to several cancers. However, there have been no reports concerning the association between thyroid cancer and L-myc gene polymorphism. Aim: To analyze the distribution of L-myc gene polymorphism in Turkish patients with thyroid disorders and thyroid cancers. Methods: We used a molecular genotyping method, polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP). We studied 138 patients of whom 47 had multinodular goiter, 13 had follicular cancer and 69 had papillar cancer, in comparison with control group of 109 healthy individuals. Results: No significant difference in the distribution of genotypes was observed between thyroid patients and controls. Carrying SS or LS genotype revealed a 1.96-fold (95% CI 0.573–6.706) risk for the occurrence of follicular cancer when compared with controls, and 3.11-fold (95% CI 0.952–10.216), when compared with multinodular goiter patients (p = 0.04). Conclusion: We suggest that L-myc genotype profiling together with other susceptibility factors, may be useful in the screening for thyroid nodular malignancy.Для ряда опухолей человека показана корреляция между риском развития опухоли и определенным вариантом гена L-MYC. Данные о наличии такой связи при раке щитовидной железы к настоящему времени отсутствуют. Цель: проанализировать распределение полиморфных типов гена L-MYC в популяции больных с доброкачественными и злокачественными поражениями щитовидной железы, включая рак щитовидной железы, в Турции. Методы: для анализа полиморфизма гена L-MYC использован метод молекулярного генотипирования, в частности, метод определения полиморфизма длины рестрикционных фрагментов, основанный на полимеразной цепной реакции (PCR-RFLP). Определение проводили в лейкоцитах 138 больных, в том числе 48 больных с узловым зобом, 13 больных фолликулярным раком щитовидной железы и 69 больных папиллярным раком. Контрольную группу составляли 109 здоровых лиц. Результаты: статистически достоверных различий в распределении исследуемых генотипов у больных с патологией щитовидной железы и здоровых лиц не выявили. Показано, что относительный риск фолликулярного рака щитовидной железы у больных-носителей генотипа SS или LS составляет 1,96 по сравнению со здоровыми лицами (при 95% доверительном интервале от 0,573 до 6,706) и 3,11 по сравнению с больными с узловым зобом (при 95% доверительном интервале от 0,952 до 10,216) (р = 0,04). Выводы: по нашему предположению, определение профиля полиморфизма гена L-MYC с учетом других факторов, определяющих предрасположенность к развитию опухолей, может быть полезным при скрининге озлокачествления узелковых образований щитовидной железы