Induction of myeloid leukaemia by whole-body single exposure of CBA male mice to x-rays.

A curvilinear dose response of myeloid leukaemia induction in the CBA male mouse was obtained after single whole-body X-irradiation at about 3 months of age. This strain has a very low spontaneous incidence of the disease and no cases were found in the unirradiated controls. The incidence was independent of dose rate over the range used (4.2-552 rad/min). Diagnosis required histopathological examination of various body tissues, the gross anatomical changes being easily confused with other haemopoietic disorders, but a few cases were recognized in life from blood samples. Curve-fitting to various models based on theories of radiocarcinogenic mechanism is described

Pulmonary Adenomata Induced by Carcinogen Treatment in Organ Culture. Influence of Increasing Amounts of Carcinogen

Explants of lung from 1 month old inbred BALB/c mice were cultured in vitro for 4 days with 3-methylcholanthrene added to the culture medium at various dose levels. They were subsequently implanted subcutaneously into 6-week-old mice of the same strain

The Induction of Adenomata in Mouse Lung Homografts by Chemical Carcinogens

Implants of lung from 18-day-old embryo BALB/c mice of an inbred strain were exposed to 3,4-benz(a)pyrene or 1,2,5,6-dibenzanthracene and introduced subcutaneously into 6-week-old mice of the same strain. Lung adenomata developed within 16 weeks

Auditor independence: a qualitative study of the perceptions of auditors

The trustworthiness of a financial audit report rests on the perception of auditor independence. However, several factors can affect those perceptions, ultimately affecting market confidence. This study aims at providing a deep understanding of auditors‟ perceptions of auditor independence, particularly analysing whether and how their perceptions are affected either by the provision of non-audit services, competition, the size and tenure of the audit firm or the client‟s financial condition. Qualitative research was held through semi-structured interviews. Both the provision of non-audit services and tenure have generated great consensus amongst interviewees as impacting auditor independence. Rotation and litigation exposure were mainly perceived as enhancement factors.info:eu-repo/semantics/publishedVersio

Ion-neutral sympathetic cooling in a hybrid linear rf Paul and magneto-optical trap

Long range polarization forces between ions and neutral atoms result in large elastic scattering cross sections, e.g., 10^6 a.u. for Na+ on Na or Ca+ on Na at cold and ultracold temperatures. This suggests that a hybrid ion-neutral trap should offer a general means for significant sympathetic cooling of atomic or molecular ions. We present SIMION 7.0 simulation results concerning the advantages and limitations of sympathetic cooling within a hybrid trap apparatus, consisting of a linear rf Paul trap concentric with a Na magneto-optical trap (MOT). This paper explores the impact of various heating mechanisms on the hybrid system and how parameters related to the MOT, Paul trap, number of ions, and ion species affect the efficiency of the sympathetic cooling

Wave Energy: The Department Of Energy'S R&D Programme 1974-1983

The intensive phase of the Department of Energy's wave energy research and development programme ran from 1974 to 1983 and cost approximately £15M. The basic objectives of the programme were to establish the feasibility of extracting energy from ocean waves and to estimate the cost of this energy, if used on a large-scale to supply UK needs

Wave Energy: The Department Of Energy'S R&D Programme 1974-1983

The intensive phase of the Department of Energy's wave energy research and development programme ran from 1974 to 1983 and cost approximately £15M. The basic objectives of the programme were to establish the feasibility of extracting energy from ocean waves and to estimate the cost of this energy, if used on a large-scale to supply UK needs

Native Speaker Perceptions of Accented Speech: The English Pronunciation of Macedonian EFL Learners

The paper reports on the results of a study that aimed to describe the vocalic and consonantal features of the English pronunciation of Macedonian EFL learners as perceived by native speakers of English and to find out whether native speakers who speak different standard variants of English perceive the same segments as non-native. A specially designed computer web application was employed to gather two types of data: a) quantitative (frequency of segment variables and global foreign accent ratings on a 5-point scale), and b) qualitative (open-ended questions). The result analysis points out to three most frequent markers of foreign accent in the English speech of Macedonian EFL learners: final obstruent devoicing, vowel shortening and substitution of English dental fricatives with Macedonian dental plosives. It also reflects additional phonetic aspects poorly explained in the available reference literature such as allophonic distributional differences between the two languages and intonational mismatch

Pointwise convergence of Birkhoff averages for global observables

It is well-known that a strict analogue of the Birkhoff Ergodic Theorem in infinite ergodic theory is trivial; it states that for any infinite-measure-preserving ergodic system the Birkhoff average of every integrable function is almost everywhere zero. Nor does a different rescaling of the Birkhoff sum that leads to a non-degenerate pointwise limit exist. In this paper we give a version of Birkhoff's theorem for conservative, ergodic, infinite-measure-preserving dynamical systems where instead of integrable functions we use certain elements of $L^\infty$, which we generically call global observables. Our main theorem applies to general systems but requires an hypothesis of "approximate partial averaging" on the observables. The idea behind the result, however, applies to more general situations, as we show with an example. Finally, by means of counterexamples and numerical simulations, we discuss the question of finding the optimal class of observables for which a Birkhoff theorem holds for infinite-measure-preserving systems.Comment: Final version. 33 pages, 10 figure