bluuebunny/crossref_metadata_2025 huggingface dataset:
An abattoir-based study on the prevalence of hydatidosis in livestock in Mashhad, Iran
Authors: Borji H. , Azizzadeh M. , Afsai A.
Published: June 2011

A 6-year (2004–2010) retrospective study was carried out to determine the prevalence of hydatidosis in livestock slaughtered in Mashhad abattoir, Mashhad, in north-eastern Iran and the capital of Khorasan province. Between 20 March 2004 and 19 March 2010, 5,131,485 animals (411,163 cattle; 4,547,618 sheep; 172,704 goats) were slaughtered in the study area and 388,399 (7.5%) livers and 1,139,529 (22.2%) lungs were discarded. Hydatidosis was responsible for 4% and 6.5% of total livers and lungs inspected, respectively. Of the cattle livers and lungs inspected over the survey period, 5.5% and 7.9% were condemned, respectively, because they held hydatid cysts. The corresponding values for livers and lungs of sheep (2%, 4%) and of goats (4.5%, 7.8%), respectively, were also condemned due to hydatidosis. Data showed a prominent seasonal pattern for hydatidosis. Liver condemnations due to hydatidosis were higher in winter and autumn for cattle and sheep, respectively, whereas lung condemnations were higher in summer for sheep and cattle. In goats, liver and lung condemnations were higher in winter. This could be attributed to various factors, such as sources of slaughtered animals, changes in management practice and ecological factors. The present survey provides baseline data for the future monitoring of this potentially important parasitic disease in the region.
The Late Minoan II–III and Mycenaean Pottery from the 1911 Excavations at Phylakopi on Melos
Authors: Mountjoy P.A.
Published: June 2011

This article presents the Late Minoan II–III B and the Late Helladic I–III C pottery from the 1911 excavations of J. Dawkins and J. Droop at Phylakopi on Melos.

The material from the 1911 excavations fills gaps in the corpus of pottery provided by the 1896–9 excavations and the 1974–7 excavations. It fills out our knowledge of the LH III A2 pottery and adds a considerable amount of LH III A1 and LH III C material. A small group of vessels caught in a LM I B/LH II A destruction confirms the supposition that full Marine Style was circulating together with open ground Marine Style and Alternating Style vases. The LH III C pottery adds some more parallels to the pottery from Koukounaries on Paros and also has one or two parallels to pottery from the east Aegean and pottery exported from there to the Levant.

Σε αυτό το άρθρο παρουσιάζεται η Υστερομινωική II–III B και η Υστεροελλαδική I–III Γ κεραμική από τις ανασκαφές των J. Dawkins και J. Droop το 1911 στη Φυλακωπή της Μήλου.

Το υλικό από τις ανασκαφές του 1911 συμπληρώνει τα κενά των δημοσιεύσεων της κεραμικής από τις ανασκαφικές περιόδους 1896–99 και 1974–77. Συμπληρώνει τη γνώση μας για την YE III A2 κεραμική και προστέτει μία σημαντική ποσόθητα υλικού της YE III A1 και YE III Γ. Ένας μικρός αριθμός αγγείων, που εντοπίστηκε στην YM I B / YE II A καταστροφή, επιβεβαιώνει την υπόθεση ότι ο πλήρης θαλάσσιος ρυθμός ήταν διαδεδομένος συγχρόνως με το θαλάσσιο ρυθμό επί ανοικτού βάθους και με τα αγγεία του εναλλασόμενου στυλ. H YE III Γ κεραμική προσθέτει ορισμένα ακόμη παράλληλα στην κεραμική από τις Κουκουναριές της Πάρου. Επιπλέον παρουσιάζει ένα ή δύο παράλληλα με την κεραμική του ανατολικού Αιγαίου, όπως και με την εξαγόμενη από εκεί κεραμική προς τη Συροπαλαιστίνη.
Casting Finger Rings in Mycenaean Times: Two Unpublished Moulds at the National Archaeological Museum, Athens
Authors: Konstantinidi-Syvridi Eleni , Kontaki Maria
Published: June 2011

The recording of two unpublished moulds in the storeroom of the Prehistoric Collections of the National Archaeological Museum, Athens, presented here, provide the stimulus for a re-examination of the construction method of the bezeled/signet rings of Mycenaean times. The moulds, one of semi-cylindrical shape and the other rectangular, belong to a limited class of items from Crete, Mainland Greece, and Enkomi, Cyprus.

It is possible that such moulds have served for the construction of the wax model of the artefacts, in the lost wax technique and not directly for the cast of gold, since the very construction of them, which is time-consuming and necessitates the skills of specialized craftsmen, indicates that they did not serve for a single use but rather for several uses. On the other hand, even steatite, the stone mostly used for such moulds, cannot adhere to continuous pressure to high temperatures, necessary for casting gold.

Στην παρούσα μελετη καταγράφονται δύο αδημοσίευτες μήτρες από την αποθήκη της Προϊστορικής Συλλογής του Εθνικού Αρχαιολογικού Μουσείου στην Αθήνα, προσφέροντας το ερέθισμα για μία επανεξέταση της τεχνικής κατασκευής των δακτυλιδιών με σφενδόνη της Μυκηναϊκής εποχής. Οι μήτρες, από τις οποίες η μία είναι ημικυλινδρική και η άλλη ορθογώνια, ανήκουν σε μία περιορισμένη τάξη ευρημάτων, που προέρχονται από την Κρήτη, την Ηπειρωτική Ελλάδα και την Έγκωμη της Κύπρου.

Είναι πιθανό ότι αυτές οι μήτρες να χρησιμοποιήθηκαν για την κατασκευή των κέρινων εκμαγείων των δακτυλιδιών κατά την τεχνική του «χαμένου κεριού» και όχι για την απευθείας χύτευση χρυσού. Η ίδια η κατασκευή τους, που προϋποθέτει πολύ χρόνο και ειδικευμένους τεχνίτες, υποδεικνύει ότι δεν χρησιμοποιήθηκαν μόνο για μία φορά. Από την άλλη πλευρά, ακόμη και ο στεατίτης, ο λίθος που κατεξοχήν χρησιμοποιήθηκε για την κατασκευή αυτών των αντικειμένων, δεν θα μπορούσε να αντέξει τις υψηλές θερμοκρασίες, που απαιτούντοα για την χύτευση του χρυσού σε διαδοχικές χρήσεις.
The structure of theC*-algebra of a locally injective surjection
Authors: CARLSEN TOKE MEIER , THOMSEN KLAUS
Published: June 2011

In this paper we investigate the ideal structure of theC*-algebra of a locally injective surjection introduced by the second-named author. Our main result is that a simple quotient of theC*-algebra of a locally injective surjection on a compact metric space of finite covering dimension is either a full matrix algebra, a crossed product of a minimal homeomorphism of a compact metric space of finite covering dimension, or it is purely infinite and hence covered by the classification result of Kirchberg and Phillips. It follows in particular that if theC*-algebra of a locally injective surjection on a compact metric space of finite covering dimension is simple, then it is automatically purely infinite, unless the map in question is a homeomorphism. A corollary of this result is that if theC*-algebra of a one-sided subshift is simple, then it is also purely infinite.
A complexity theory of design intentionality
Authors: Zamenopoulos Theodore
Published: June 2011

The subject of this paper is design intentionality. The paper is concerned with the property of the mind to hold intentional states (its capacity to represent or reflect existing and nonexisting realities) and with the way that these mental states are constructed during design tasks. The aim is to develop a mathematical theory of design intentionality, capturing the structures and processes that characterize an intentional system with the mental ability to address design tasks. The philosophical notion of intentionality is approached methodologically from a complexity theoretic perspective. More specifically, the focus is placed on the mathematical characterization of the organizational complexity of intentional states and the type of phase transitions that occur on the mental states of an intentional system during design tasks. The paper uses category theory in order to build a framework that is able to mathematically capture the meaning of these notions.
The Wilkie Model for Retail Price Inflation Revisited
Authors: Chan W.S. , Wang S.
Published: June 2011

A first order autoregressive model was proposed in Wilkie (1995) for the retail price inflation series as a part of his stochastic investment model. In this paper we apply time series outlier analysis to the data set and a revised model is derived. It significantly alleviates the problem of leptokurtic and positive skewed residual distribution as found in the original model. Finally, ARCH models for the original series and the outlier-adjusted data are also considered.
The Puzzle of Life Office Tax
Authors: Sole T.C.
Published: June 2011

This paper takes a broad look at tax in general and some of the tax issues peculiar to life offices. A theoretical model for the taxation of life offices and their policyholders is then developed. Moving from theory to practice, the paper then offers its own solution to the ‘puzzle’. Appended by way of background reading are brief histories and summaries of life office tax in the UK, New Zealand, USA and Canada.
The Risk Premium on Ordinary Shares
Authors: Wilkie A.D.
Published: June 2011

The risk premium on ordinary shares is investigated, by studying the total returns on ordinary shares, and on both long-term and short-term fixed-interest investments over the period 1919 to 1994, and by analysing the various components of that return. The total returns on ordinary shares exceeded those on fixed-interest investments by over 5% p.a. on a geometric mean basis and by over 7% p.a. on an arithmetic mean basis, but it is argued that these figures are misleading, because most of the difference can be accounted for by the fact that price inflation turned out to be about 4.5% p.a. over the period, whereas investors had been expecting zero inflation.

Quotations from contemporary authors are brought forward to demonstrate what contemporary attitudes were. Simulations are used along with the Wilkie stochastic asset model to show what the results would be if investors make various assumptions about the future, but the true model turns out to be different from what they expected. The differences between geometric means of the data and arithmetic means are shown to correspond to differences between using medians or means of the distribution of future returns, and it is suggested that, for discounting purposes, medians are the better measure.
More on a Stochastic Asset Model for Actuarial Use
Authors: Wilkie A.D.
Published: June 2011

In this paper the ‘Wilkie investment model’ is discussed, updated and extended. The original model covered price inflation, share dividends, share dividend yields (and hence share prices) and long-term interest rates, and was based on data for the United Kingdom from 1919 to 1982, taken at annual intervals. The additional aspects now covered include: the extension of the data period to 1994 (with omission of the period from 1919 to 1923); the inclusion of models for a wages (earnings) index, short-term interest rates, property rentals and yields (and hence property prices) and yields on index-linked stock; consideration of data for observations more frequently than yearly, in particular monthly data; extension of the U.K. model to certain other countries; introduction of a model for currency exchange rates; extension of certain aspects of the model to a larger number of other countries; and consideration of more elaborate forms of time-series modelling, in particular cointegrated models and ARCH models.
General Insurance Premium Rating — The Way Forward. Summary of the Recommendations of the General Insurance Premium Rating Working Party (GRIP)
Authors: Anderson J. D. , Bolton C. G. , Callan G. L. , Cross M. , Howard S. K. , Mitchell G. R. J. , Murphy K. P. , Rakow J. C. , Stirling P. A. , Welsh G. E.
Published: June 2011

The General Insurance Premium Rating Issues Working Party (GRIP) was established by the General Insurance Board of the Faculty and Institute of Actuaries in 2005 to review actuarial involvement in premium rating issues, pricing being one of the key areas in which actuaries work.

GRIP published a full report in January 2007, which is available at www.actuaries.org.uk/grip. This short paper summarises the recommendations of that full report. Further background, discussion and the rationale for these recommendations are set out in more detail in the full report.
Pension Scheme Asset Allocation with Taxation Arbitrage, Risk Sharing and Default Insurance
Authors: Sutcliffe C. M. S.
Published: June 2011

The asset allocation is a crucial decision for pension funds, and this paper analyses the economic factors which determine this choice. The analysis proceeds on the basis that, in the absence of taxation, risk sharing and default insurance, the asset allocation between equities and bonds is indeterminate and governed by the risk/return preferences of the trustees and the employer. If the employing company and its shareholders are subject to taxation, there is a tax advantage in a largely bond allocation. Risk sharing between the employer and the employees often means that one group favours a high equity allocation, while the other favours a low equity allocation. Underpriced default insurance creates an incentive for a high equity allocation. When taxation, risk sharing and underpriced default insurance are all present, it is concluded that the appropriate asset allocation varies with the circumstances of the scheme; but that a high equity allocation is probably inappropriate for many private sector pension schemes.
The Economy, Society and the Actuarial Profession 1856-2006
Authors: Simpson D. R. F.
Published: June 2011

The paper identifies two major trends in the economic and social history of the last 150 years, and discusses their effect on the actuarial profession. The major economic trend is globalisation, with which is associated specialisation of function. The major social trend is the gradual collectivisation of society. Neither of these trends has developed monotonically. Both have developed in a ratchet-like movement over time. Globalisation is reflected in the overseas expansion of British life assurance companies up to 1914, followed by an extended period of retrenchment before expansion was resumed in the last quarter of the 20th century. The effect of the collectivisation of society on the actuarial profession has been felt most acutely in an intensification of the regulation of financial services.
An Actuarial Survey of Statistical Models for Decrement and Transition Data - I: Multiple State, Poisson and Binomial Models
Authors: Macdonald A.S.
Published: June 2011

This paper surveys some statistical models of survival data. A basic model of a random lifetime is defined, and censoring is introduced. Methods based on observations of small segments of lifetimes are compared. Markov and semi-Markov (multiple state) models are recommended as well-understood and flexible models well suited to actuarial data. A Poisson model is discussed as an approximation to a two state model, while traditional Binomial-type models are shown to be more restricted and less tractable than multiple state models.
The Recent Trend of Mortality in the United Kingdom
Authors: Daykin C.D.
Published: June 2011

This note continues a regular series on mortality rates in the United Kingdom. Mortality experienced in 1993 is shown by five-year age groups, and comparisons are made for broad age groups, on a standardised basis, with mortality in earlier years.
An Actuarial Survey of Statistical Models for Decrement and Transition Data, II. Competing Risks, Non-Parametric and Regression Models
Authors: Macdonald A.S.
Published: June 2011

This paper surveys some statistical models of survival data. Competing risks models are described; the unidentifiability of net decrements suggests a sceptical approach to the use of underlying single decrement tables. Approaches based on observations of complete lifetimes (with censoring) are surveyed including the Kaplan-Meier and Nelson-Aalen estimates. Regression models for lifetimes depending on covariates are discussed, in particular the Cox model and partial likelihood estimation.
The Joint Development of Insurance and Investment Markets in Poland: An Analysis of Actuarial Risks
Authors: Booth P.M. , Stroinski K.J.
Published: June 2011

The development of the Polish insurance market in the period since liberalisation is discussed. The nature of the investment market and the investment risk faced by insurers are analysed in the context of the liability structure of Polish insurance companies. The likely future developments in insurance and investment markets are outlined, particularly given the structure of the state social insurance system, possible reforms of which are discussed in detail.
A Multi-State Model of Disability for the United Kingdom: Implications for Future Need for Long-Term Care for the Elderly
Authors: Rickayzen B.D. , Walsh D.E.P.
Published: June 2011

This paper develops a multiple state model to project the number of people with disabilities in the United Kingdom over the next 35 years, thereby identifying implications for demand for long-term care for the elderly in the future.

The model requires three types of data: prevalence rate data, transition rate data and trends data. Recent trends in healthy life expectancy data are used to frame the assumptions made regarding changes in the disability rates of the U.K. population in the future.

Although there will be a large increase in the number of elderly people in the U.K. over the next 35 years, the projections suggest that the implications for the number of elderly people requiring long-term care could be ameliorated by a reduction in the proportion of older people who are severely disabled.
A Review of Policyholders' Reasonable Expectations
Authors: Shelley M. , Arnold M. , Needleman P. D.
Published: June 2011

In the light of recent judgments by the courts, there are areas where the interpretation of Policyholders' Reasonable Expectations (PRE) by actuaries may need to be reassessed. Furthermore, the discussion paper on the exercise of discretion expected from the Financial Services Authority (FSA), as part of its review of with-profits business, is likely to raise wider issues.

The time is therefore right for actuaries to have the opportunity to debate how PRE should be interpreted in the future. This paper is presented as a catalyst to enable that debate to happen, and the authors have set out their own views on some of the key issues.

The paper discusses certain areas where the interpretation of PRE adopted by Appointed Actuaries in the past may no longer be consistent with recent court judgments. Following that discussion, the actuarial profession should attempt to establish a revised interpretation of PRE, in order to provide greater assistance to Appointed Actuaries currently advising on with-profits business.
Risk Measures and Theories of Choice
Authors: Tsanakas A. , Desli E.
Published: June 2011

We discuss classes of risk measures in terms both of their axiomatic definitions and of the economic theories of choice that they can be derived from. More specifically, expected utility theory gives rise to the exponential premium principle, proposed by Gerber (1974), Dhaene et al. (2003), whereas Yaari's (1987) dual theory of choice under risk can be viewed as the source of the distortion premium principle (Denneberg, 1990; Wang, 1996). We argue that the properties of the exponential and distortion premium principles are complementary, without either of the two performing completely satisfactorily as a risk measure. Using generalised expected utility theory (Quiggin, 1993), we derive a new risk measure, which we call the distortion-exponential principle. This risk measure satisfies the axioms of convex measures of risk, proposed by Föllmer & Shied (2002a,b), and its properties lie between those of the exponential and distortion principles, which can be obtained as special cases.
How Actuaries Can Use Financial Economics
Authors: Smith A.D.
Published: June 2011

There has recently been some debate about the usefulness of financial economics to the actuarial profession. The consensus appears to be that the techniques are potentially valuable, but the published material is not quite ‘oven ready’. Some development work is required before the material can be applied.

The author has carried out much of the necessary development work on behalf of various clients over the last few years. On some occasions the results have conflicted with more conventional actuarial methods. The main aim of the paper is to bring the new techniques into the public domain so that they can be properly discussed by the profession, and adopted more widely if appropriate.

The paper contains a number of worked examples using techniques developed by financial economists. The author has listed the computer code which generated the examples and deposited copies on the Internet, so that others can explore the issues with a minimal development overhead.
Pension Funding and Expensing in the Minimum Funding Requirement Environment
Authors: Greenwood P.M. , Keogh T.W.
Published: June 2011

The statutory Minimum Funding Requirement (MFR) introduces fundamental change to the funding of pension schemes in the United Kingdom. While only a minority of schemes will actually be affected materially in terms of actual contributions or benefits, taken over a period of years, the influence of MFR will be much more widely felt. This is because the MFR is an absolute standard to be met, whereas long-term funding targets for ongoing schemes are, at least up to a point, optional and adjustable. The paper discusses the difference between MFR and long-term funding and suggests a variation on traditional actuarial methods to control explicitly the risk of MFR failure, based on a combination of traditional methods and the theories underlying asset/liability modelling. The paper also discusses the implications for pension expensing and communication of funding levels.
Business Ethics: The New Bottom Line. A Discussion Paper
Authors: Carmichael S.
Published: June 2011

This discussion meeting was on the subject of business ethics, with particular reference to the work of actuaries.

As an introduction to the meeting, copies of the paper, ‘Business Ethics: the New Bottom Line’, by Sheena Carmichael, were distributed to members of the Institute.

Sheena Carmichael is the director of ETHOS, a consultancy dedicated to helping organisations identify and manage ethical issues. She is a research associate at the European Institute of Business Ethics at Nigenrode University in the Netherlands.

The paper ‘Business Ethics: the New Bottom Line’, was published in 1995 by Demos, which “is an independent think-tank committed to radical thinking on the long-term problems facing the United Kingdom and other advanced industrial societies.

It aims to develop the ideas — both theoretical and practical — that will shape the politics of the 21st century, and to improve the breadth and quality of political debate.” It is a registered charity.

The paper has not been reproduced in British Actuarial Journal, but further information can be obtained from:

Demos, 9 Bridewell Place, London, EC4V 6AP; telephone: 0171 353 4479; facsimile, 0171 353 4481; email, martin@demos.demon.co.uk
Scoping Mortality Research: (Report of the Mortality Research Steering Group)
Authors: Macdonald C.
Published: June 2011

The Actuarial Profession is currently undertaking a review of its research strategy, and has decided to focus more resources on researching mortality developments. It is important that the profession is involved in partnerships with researchers from outside of the profession, bringing actuarial expertise into closer contact with other disciplines. We believe that collaboration between these different areas of expertise will provide important new insights in understanding mortality trends. This report represents the first step by the Mortality Developments Scoping Project Steering Group to map current research into mortality developments across a wide range of disciplines. The steering group is aware that the themes and literature discussed in this report are not exhaustive; however it does include areas of research not normally covered by the Actuarial Profession. The steering group welcomes comments on the report and suggestions for any areas which may not yet have been covered.

The main aim of this report is to provide an overview of the key areas of research into mortality developments across a wide range of disciplines, as well as areas of overlap and gaps in the research. The literature described is compiled from recommendations received by the Mortality Developments Scoping Project Steering Group from experts from different disciplines working in the area of mortality.

Key themes identified from recommended literature:

— the role of medicine in mortality reduction;

— the role of lifestyle and environment in mortality reduction, including smoking, socio-economic conditions and obesity;

— causes of death contributing to mortality reduction, in particular coronary heart disease;

— mortality reduction attributable to differing age groups;

— the relationship of active life expectancy to total gains in life expectancy;

— evidence of cohort effects on mortality improvement; and

— future trends in mortality developments.

Areas of overlap identified from recommended literature are:

— the overlap between literature examining the role of medicine in mortality decline and the influences on the decline in mortality from coronary heart disease; and

— the areas of overlap between various disciplines working in the field of mortality developments.

Gaps identified in recommended literature are:

— a lack of recommendations from social policy;

— few papers recommended on the role of lifestyle and behavioural factors on mortality;

— few papers recommended on causes of death other than coronary heart disease; and

— few papers recommended on potential threats to future mortality improvement.
Prospective Longevity Risk Analysis
Authors: Woo G. , Martin C. J. , Hornsby C. , Coburn A. W.
Published: June 2011

Mortality improvement has traditionally been analysed using an array of statistical methods, and extrapolated to make actuarial projections. This paper presents a forward-looking approach to longevity risk analysis which is based on stochastic modelling of the underlying causes of mortality improvement, due to changes in lifestyle, health environment, and advances in medical science. The rationale for this approach is similar to that adopted for modelling other types of dynamic insurance risk, e.g. natural catastrophes, where risk analysts construct a stochastic ensemble of events that might happen in the future, rather than rely on a retrospective analysis of the non-stationary and comparatively brief historical record.

Another feature of prospective longevity risk analysis, which is shared with catastrophe risk modelling, is the objective of capturing vulnerability data at a high resolution, to maximise the benefit of detailed modelling capability down to individual risk factor level. Already, the use by insurers of postcode data for U.K. flood risk assessment has carried over to U.K. mortality assessment. Powered by fast numerical computation and parameterised with high quality geographical data, hydrological models of flood risk have superseded the traditional statistical insurance loss models. A decade later, medically-motivated computational models of mortality risk can be expected to gain increasing prominence in longevity risk management.
Distributions of Heat Shock Protein-70 mRNAs and Heat Shock Cognate Protein-70 mRNAs after Transient Global Ischemia in Gerbil Brain
Authors: Kawagoe J. , Abe K. , Sato S. , Nagano I. , Nakamura S. , Kogure K.
Published: June 2011

Distributions of heat shock protein (HSP)-70 mRNAs and heat shock cognate protein (HSC)-70 mRNAs after 10 min of transient global ischemia were investigated in gerbil forebrain by in situ hybridization using cloned cDNA probes selective for the mRNAs. Expression of HSP70 immunoreactivity was also examined in the same brains. In hippocampal CA1 neuronal cells, in which only a minimal induction of immunoreactive HSP70 protein was found, the strong hybridization for HSP70 mRNA disappeared at around 2 days before the death of CA1 cells became evident. Furthermore, in hippocampal CA3 cells, a striking induction of HSP70 mRNA was sustained even at 2 days along with a prominent accumulation of HSP70 immunoreactivity. In contrast to the case of HSP70 mRNA, HSC70 mRNA was present in most neuronal cells, especially dense in CA3 cells, of the sham brain. A co-induction of HSP70 and HSC70 mRNAs was observed in several cell populations after the reperfusion with a peak at 8 h, although the magnitude of HSC70 mRNA induction was lower than that of HSP70 mRNA, particularly in CA1 cells. The expression of HSC70 mRNA in CA1 cells also disappeared at around 2 days. All the induced signals of HSP70 and HSC70 mRNAs in other cell populations were diminished and returned to the sham level, respectively, by 7 days. These results are the first to show the time courses of distribution of HSP70 and HSC70 mRNAs and the immunoreactive HSP70 protein in the same gerbil brain after ischemia. The results suggest that the weak induction of HSP70 protein in CA1 cells, which may relate to the vulnerability of this cell population, is due to both translational and transcriptional deficits. The different roles under normal condition and the cooperative role in the recovery process from ischemic injury between HSP70 and HSC70, and the involvement of HSC70 in CA1 cell death, are suggested.
Regulation of Cerebral Glucose Metabolism in Normal and Polycythemic Newborn Lambs
Authors: Rosenkrantz Ted S. , Philipps Anthony F. , Knox Isabella , Zalneraitis Edwin L. , Porte Patricia J. , Skrzypczak Peter E. , Raye John R.
Published: June 2011

In contrast to previous investigations, a recent study of polycythemic lambs suggested that cerebral glucose delivery (concentration × blood flow), not arterial glucose concentration, determined cerebral glucose uptake. In the present study, the independent effects of arterial glucose concentration and delivery on cerebral glucose uptake were examined in two groups of chronically catheterized newborn lambs (control and polycythemic). Arterial glucose concentration was varied by an infusion of insulin. CBF was reduced in one group of lambs (polycythemic) by increasing the hematocrit. At all arterial glucose concentrations, the cerebral glucose delivery of the polycythemic group was 59.6% of the control group. At arterial glucose concentrations of > 1.6 mmol/L, cerebral glucose uptake was constant and similar in both groups. At arterial glucose concentrations of ≤1.6 mmol/L, cerebral glucose uptake was unchanged in the control group, but was significantly decreased in the polycythemic group. In contrast, the cerebral glucose uptake was similar in both groups over a broad range of cerebral glucose delivery values. At cerebral glucose delivery values ≤83 μmol/min/100 g, there was a significant decrease in cerebral glucose uptake in both groups. During periods of low cerebral glucose delivery and uptake, cerebral oxygen uptake fell in the control group but remained unchanged in the polycythemic group. Maintenance of cerebral oxygen uptake in the polycythemic group was associated with an increased extraction and uptake of lactate and β-hydroxybutyrate. We conclude that cerebral glucose delivery, not arterial glucose concentration alone, determines cerebral glucose uptake.
Intracerebral Microdialysis of Extracellular Amino Acids in the Human Epileptic Focus
Authors: Ronne-Engström Elisabeth , Hillered Lars , Flink Roland , Spännare BO , Ungerstedt Urban , Carlson Hans
Published: June 2011

Extracellular levels of aspartate (ASP), glutamate (GLU), serine (SER), asparagine (ASN), glycine (GLY), threonine (THR), arginine (ARG), alanine (ALA), taurine (TAU), tyrosine (TYR), phenylalanine (PHE), isoleucine (ILEU), and leucine (LEU) were monitored by using intracerebral microdialysis in seven patients with medically intractable epilepsy, undergoing epilepsy surgery. In association with focal seizures, dramatic increases of the extracellular ASP, GLU, GLY, and SER concentrations were observed. The other amino acids analyzed, including TAU, showed small changes. The results support the hypothesis that ASP, GLU, GLY, and possibly SER, play an important role in the mechanism of seizure activity and seizure-related brain damage in the human epileptic focus.
Discovery of novel selective Sigma-1 ligands as cognitive enhancers
Authors: Valade Anne , Cross Sophie Binet , Brown Claire , Detrait Eric , Ene Doina , Gillard Michel , Guyaux Michel , Lamberty Yves , Maguire Martin , Namdev Nivedita , Provins Laurent , Schwartz Eric , Vermeiren Céline
Published: June 2011

Novel drug-like and selective Sigma-1 ligands have been prepared and pharmacologically evaluated in a mouse model of cognitive deficits.
Use of plasma treatment to grow carbon nanotube forests on TiN substrate
Authors: Esconjauregui S. , Bayer B. C. , Fouquet M. , Wirth C. T. , Yan F. , Xie R. , Ducati C. , Baehtz C. , Castellarin-Cudia C. , Bhardwaj S. , Cepek C. , Hofmann S. , Robertson J.
Published: June 2011

Hydrogen plasma pretreatment is used to enforce the growth of vertically-aligned carbon nanotube forests on TiN substrates. The evolution of the substrate, catalyst, and nanotubes are studied by in situ and ex-situ photoemission and X-ray diffraction in order to understand the growth mechanism. We find that TiN retains its crystallographic structure and its conductivity during plasma pretreatment and nanotube growth, which is confirmed by electrical measurements. Plasma pretreatment is found to favor the growth of nanotube forests by root growth, as it binds the catalyst nanoparticles more strongly to the substrate than thermal pretreatment. We find that plasma pretreatment time should be limited, otherwise poor or no growth is found.
Gyromap for a two-dimensional Hamiltonian fluid model derived from Braginskii’s closure for magnetized plasmas
Authors: Izacard O. , Chandre C. , Tassi E. , Ciraolo G.
Published: June 2011

We consider a plasma described by means of a two-dimensional fluid model across a constant but non-uniform magnetic field B=B(x,y)z∧. The dynamical evolution of the density and the vorticity takes into account the interchange instability and magnetic field inhomogeneities. First, in order to describe the finite Larmor radius effects, we apply the gyromap to build a Hamiltonian model with ion temperature from a cold-ion model. Second, we show that the gyromap is justified using Braginskii’s closure for the stress tensor as well as an apt ordering on the fluctuating quantities.
Impact of a shear flow on double tearing nonlinear dynamics
Authors: Voslion T. , Agullo O. , Beyer P. , Yagi M. , Benkadda S. , Garbet X. , Itoh K. , Itoh S-I.
Published: June 2011

The dynamics of global reconnection in the presence of a poloidal shear flow located in between magnetic islands is investigated. Different linear and nonlinear regimes are identified depending on the resistivity, the equilibrium velocity amplitude, and the distance between the low-order resonant surfaces. It is found that nonlinearly, the shear flow can significantly delay DTM generation and global reconnection. It is shown that this delay is linked to a symmetry breaking imposed by the shear flow and the generation of mean poloidal flows in the resistive layers. It is also found that turbulence can be generated by Kelvin-Helmholtz instability in between the resonance layers and enhance magnetic reconnection processes.
Shear flow instability in a partially-ionized plasma sheath around a fast-moving vehicle
Authors: Sotnikov V. I. , Mudaliar S. , Genoni T. C. , Rose D. V. , Oliver B. V. , Mehlhorn T. A.
Published: June 2011

The stability of ion acoustic waves in a sheared-flow, partially-ionized compressible plasma sheath around a fast-moving vehicle in the upper atmosphere, is described and evaluated for different flow profiles. In a compressible plasma with shear flow, instability occurs for any velocity profile, not just for profiles with an inflection point. A second-order differential equation for the electrostatic potential of excited ion acoustic waves in the presence of electron and ion collisions with neutrals is derived and solved numerically using a shooting method with boundary conditions appropriate for a finite thickness sheath in contact with the vehicle. We consider three different velocity flow profiles and find that in all cases that neutral collisions can completely suppress the instability.
Ultrathin (1×2)-Sn layer on GaAs(100) and InAs(100) substrates: A catalyst for removal of amorphous surface oxides
Authors: Laukkanen P. , Punkkinen M. P. J. , Lång J. , Tuominen M. , Kuzmin M. , Tuominen V. , Dahl J. , Adell J. , Sadowski J. , Kanski J. , Polojärvi V. , Pakarinen J. , Kokko K. , Guina M. , Pessa M. , Väyrynen I. J.
Published: June 2011

Amorphous surface oxides of III–V semiconductors are harmful in many contexts of device development. Using low-energy electron diffraction and photoelectron spectroscopy, we demonstrate that surface oxides formed at Sn-capped GaAs(100) and InAs(100) surfaces in air are effectively removed by heating. This Sn-mediated oxide desorption procedure results in the initial well-defined Sn-stabilized (1×2) surface even for samples exposed to air for a prolonged time. Based on ab initio calculations we propose that the phenomenon is due to indirect and direct effects of Sn. The Sn-induced surface composition weakens oxygen adsorption.
Observation of band gaps in the gigahertz range and deaf bands in a hypersonic aluminum nitride phononic crystal slab
Authors: Gorisse M. , Benchabane S. , Teissier G. , Billard C. , Reinhardt A. , Laude V. , Defaÿ E. , Aïd M.
Published: June 2011

We report on the observation of elastic waves propagating in a two-dimensional phononic crystal composed of air holes drilled in an aluminum nitride membrane. The theoretical band structure indicates the existence of an acoustic band gap centered around 800 MHz with a relative bandwidth of 6.5% that is confirmed by gigahertz optical images of the surface displacement. Further electrical measurements and computation of the transmission reveal a much wider attenuation band that is explained by the deaf character of certain bands resulting from the orthogonality of their polarization with that of the source.
Transition from strong to ultrastrong coupling regime in mid-infrared metal-dielectric-metal cavities
Authors: Jouy P. , Vasanelli A. , Todorov Y. , Delteil A. , Biasiol G. , Sorba L. , Sirtori C.
Published: June 2011

We have investigated the transition from strong to ultrastrong coupling regime between a mid-infrared intersubband excitation and the fundamental mode of a metal-dielectric-metal microcavity. The ultrastrong coupling regime is demonstrated up to room temperature for a wavelength of 11.7 μm by using 260 nm thick cavities, which impose an extreme subwavelength confinement. By varying the doping of our structures we show that the experimental signature of the transition to the ultrastrong coupling regime is the opening of a photonic gap in the polariton dispersion. The width of this gap depends quadratically on the ratio between the Rabi and intersubband transition energies.
On the mechanism of the highly viscous flow
Authors: Buchenau U.
Published: June 2011

The asymmetry model for the highly viscous flow postulates thermally activated jumps from a practically undistorted ground state to strongly distorted, but stable structures, with a pronounced Eshelby backstress from the distorted surroundings. The viscosity is ascribed to those stable distorted structures which do not jump back, but relax by the relaxation of the surrounding viscoelastic matrix. It is shown that this mechanism implies a description in terms of the shear compliance, with a viscosity which can be calculated from the cutoff of the retardation spectrum. Consistency requires that this cutoff lies close to the Maxwell time. The improved asymmetry model compares well with experiment.
Scattering of scalar waves by many small particles
Authors: Ramm Alexander G.
Published: June 2011

Formulas are derived for solutions of many-body wave scattering problems by small particles in the case of acoustically soft, hard, and impedance particles embedded in an inhomogeneous medium. The limiting case is considered, when the size a of small particles tends to zero while their number tends to infinity at a suitable rate. Equations for the limiting effective (self-consistent) field in the medium are derived.
Cross-Border Regionalization, the INTERREG III a Initiative, and Local Cooperation at the Finnish-Swedish Border
Authors: Prokkola Eeva-Kaisa
Published: June 2011

Whereas most studies to date have viewed cross-border regionalization and cooperation from ‘top-down’ regional and institutional perspectives, and within the context of urban regions, I am concerned with the implementation of cross-border initiatives in the rural Finnish–Swedish border area. The focus is firstly on the implementation of cross-border projects in the European Union's INTERREG III A North programme (2000–06), and secondly on grassroots cooperation and local actors' experiences of cross-border initiatives. The findings indicate that cooperation is not a straightforward process of ‘ignoring’ state borders and creating new regional spaces across borders. The INTERREG programme documents emphasize the development of a functional, harmonious cross-border region. When the examination is moved to the local level and everyday institutional practices are considered, cooperation and the implementation of initiatives appear in a rather different light. Practices of cooperation are intertwined with different governmental and nongovernmental structures across multiple scales, but it is the state border which determines the norms and spatial organization of this cooperation and cross-border networks are still sparse compared with their national counterparts. What this paper suggests is that we should include the national as a significant scalar dimension more profoundly in our analysis of cross-border regionalization and cooperation.
Jellyfish blooms result in a major microbial respiratory sink of carbon in marine systems
Authors: Condon Robert H. , Steinberg Deborah K. , del Giorgio Paul A. , Bouvier Thierry C. , Bronk Deborah A. , Graham William M. , Ducklow Hugh W.
Published: June 2011

Jellyfish blooms occur in many estuarine and coastal regions and may be increasing in their magnitude and extent worldwide. Voracious jellyfish predation impacts food webs by converting large quantities of carbon (C), fixed by primary producers and consumed by secondary producers, into gelatinous biomass, which restricts C transfer to higher trophic levels because jellyfish are not readily consumed by other predators. In addition, jellyfish release colloidal and dissolved organic matter (jelly-DOM), and could further influence the functioning of coastal systems by altering microbial nutrient and DOM pathways, yet the links between jellyfish and bacterioplankton metabolism and community structure are unknown. Here we report that jellyfish released substantial quantities of extremely labile C-rich DOM, relative to nitrogen (25.6 ± 31.6 C:1N), which was quickly metabolized by bacterioplankton at uptake rates two to six times that of bulk DOM pools. When jelly-DOM was consumed it was shunted toward bacterial respiration rather than production, significantly reducing bacterial growth efficiencies by 10% to 15%. Jelly-DOM also favored the rapid growth and dominance of specific bacterial phylogenetic groups (primarily γ-
proteobacteria
) that were rare in ambient waters, implying that jelly-DOM was channeled through a small component of the in situ microbial assemblage and thus induced large changes in community composition. Our findings suggest major shifts in microbial structure and function associated with jellyfish blooms, and a large detour of C toward bacterial CO
2
production and away from higher trophic levels. These results further suggest fundamental transformations in the biogeochemical functioning and biological structure of food webs associated with jellyfish blooms.
Using Electronic Health Information to Risk-Stratify Rates of Clostridium difficile Infection in US Hospitals
Authors: Zilberberg Marya D. , Tabak Ying P. , Sievert Dawn M. , Derby Karen G. , Johannes Richard S. , Sun Xiaowu , McDonald L. Clifford
Published: June 2011

Background.

Expanding hospitalized patients' risk stratification for Clostridium difficile infection (CDI) is important for improving patient safety. We applied definitions for hospital-onset (HO) and community-onset (CO) CDI to electronic data from 85 hospitals between January 2007 and June 2008 to identify factors associated with higher HO CDI rates.

Methods.

Nonrecurrent CDI cases were identified among adult (≥18-year-old) inpatients by a positive C. difficile toxin assay result more than 8 weeks after any previous positive result. Case categories included HO, CO-hospital associated (CO-HA), CO-indeterminate hospital association (CO-IN), and CO–non–hospital associated (CO-NHA). C. difficile testing intensity (CDTI) was defined as the total number of C. difficile tests performed, normalized to the number of patients with at least 1 C. difficile toxin test recorded. We calculated both the incidence density and the prevalence of CDI where appropriate. We fitted a multivariable Poisson model to identify factors associated with higher HO CDI rates.

Results.

Among 1,351,156 unique patients with 2,022,213 admissions, 9,803 cases of CDI were identified; of these, 50.6% were HO, 17.4% were CO-HA, 9.0% were CO-IN, and 23.0% were CO-NHA. The incidence density of HO was 6.3 per 10,000 patient-days. The prevalence of CO CDI on admission was, per 10,000 admissions, 8.4 for CO-HA, 4.4 for CO-IN, and 11.1 for CO-NHA. Factors associated (P< .0001) with higher HO CDI rates included older age, higher CO-NHA prevalence on admission, and increased CDTI.

Conclusion.

Electronic health information can be leveraged to risk-stratify HO CDI rates by patient age and CO-NHA prevalence on admission. Hospitals should optimize diagnostic testing to improve patient care and measured CDI rates.
RNASAlign: RNA Structural Alignment System
Authors: Wong Thomas K. F. , Wan Kwok-Lung , Hsu Bay-Yuan , Cheung Brenda W. Y. , Hon Wing-Kai , Lam Tak-Wah , Yiu Siu-Ming
Published: June 2011

Motivation: Structural alignment of RNA is found to be a useful computational technique for idenitfying non-coding RNAs (ncRNAs). However, existing tools do not handle structures with pseudoknots. Although algorithms exist that can handle structural alignment for different types of pseudoknots, no software tools are available and users have to determine the type of pseudoknots to select the appropriate algoirthm to use which limits the usage of structural alignment in identifying novel ncRNAs.

Results: We implemented the first web server, RNASAlign, which can automatically identify the pseudoknot type of a secondary structure and perform structural alignment of a folded RNA with every region of a target DNA/RNA sequence. Regions with high similarity scores and low e-values, together with the detailed alignments will be reported to the user. Experiments on more than 350 ncRNA families show that RNASAlign is effective.

Availability:  http://www.bio8.cs.hku.hk/RNASAlign.

Contact:  smyiu@cs.hku.hk
mapDamage: testing for damage patterns in ancient DNA sequences
Authors: Ginolhac Aurelien , Rasmussen Morten , Gilbert M. Thomas P. , Willerslev Eske , Orlando Ludovic
Published: June 2011

Summary: Ancient DNA extracts consist of a mixture of contaminant DNA molecules, most often originating from environmental microbes, and endogenous fragments exhibiting substantial levels of DNA damage. The latter introduce specific nucleotide misincorporations and DNA fragmentation signatures in sequencing reads that could be advantageously used to argue for sequence validity. mapDamage is a Perl script that computes nucleotide misincorporation and fragmentation patterns using next-generation sequencing reads mapped against a reference genome. The Perl script outputs are further automatically processed in embedded R script in order to detect typical patterns of genuine ancient DNA sequences.

Availability and implementation: The Perl script mapDamage is freely available with documentation and example files at http://geogenetics.ku.dk/all_literature/mapdamage/. The script requires prior installation of the SAMtools suite and R environment and has been validated on both GNU/Linux and MacOSX operating systems.

Contact:  aginolhac@snm.ku.dk

Supplementary information:  Supplementary data available at Bioinformatics online