bluuebunny/crossref_metadata_2025 huggingface dataset:
INFORMATION GATHERING BY A PRINCIPAL*
Authors: Nosal Ed
Published: October 2006

In the standard principal–agent model, the information structure is fixed. In this article the principal can choose to acquire additional information about the state of the world before he contracts with an agent. In the event that the principal acquires this information, the agent never learns what the principal knows about the state of the world. I examine cases where the agent can and cannot observe whether the principal has acquired the additional information. The implications for risk sharing, information acquisition, investment, and welfare are examined for both cases.
DISENTANGLING THE COLLEGE WAGE PREMIUM: ESTIMATING A MODEL WITH ENDOGENOUS EDUCATION CHOICES*
Authors: Fang Hanming
Published: October 2006

This article proposes and empirically implements a structural model of education choices and wage determination to quantitatively evaluate the contributions of productivity enhancement and ability signaling in the college wage premium. The model is estimated under various distributional parameterizations using 1990 U.S. Census 5% Public Use Micro Sample. Under these parameterizations, I find that college education enhances attendees' productivity by about 40%, and productivity enhancement accounts for close to two‐thirds of the college wage premium.
ON THE OUTPUT EFFECTS OF BARRIERS TO TRADE*
Authors: Ferreira Pedro Cavalcanti , Trejos Alberto
Published: October 2006

We study the macroeconomic effects of international trade policy by integrating a Hecksher–Ohlin trade model into an optimal‐growth framework. The model predicts that a more open economy will have higher factor productivity. Furthermore, there is a “selective development trap” to which countries may or may not converge, depending on policy. Income at the development trap falls as trade barriers increase. Hence, cross‐country differences in barriers to trade may help explain the dispersion of per capita income observed across countries. The effects are quantified, and we show that protectionism can explain a relevant fraction of TFP and long‐run income differentials across countries.
JAMES WATT AS INTELLECTUAL MONOPOLIST: COMMENT ON BOLDRIN AND LEVINE*
Authors: Selgin George , Turner John
Published: October 2006

In their 2003 Lawrence R. Klein Lecture, Michele Boldrin and David Levine argue that intellectual property rights may be damaging to social welfare. As empirical evidence for their theory they offer James Watt's steam engine patent, claiming that it delayed the Industrial Revolution by as much as two decades. We show that this claim, as well as the more general claim that Watt's story supports Boldrin and Levine's theory, rests upon a distorted summary of the historical record.
Haemochromatosis Gene (HFE) Polymorphisms and Migraine: An Association Study
Authors: Rainero I , Rubino E , Rivoiro C , Valfrè W , Binello E , Zampella E , Martino P De , Gentile S , Fenoglio P , Savi L , Gallone S , Pinessi L
Published: October 2006

Several studies have suggested that iron metabolism may be involved in the pathogenesis of migraine. Using a case-control design, we performed an association study in a cohort of Italian migraine patients to evaluate whether a particular allele or genotype of the haemochromatosis gene ( HFE) would modify the occurrence and clinical features of the disease. We genotyped 256 migraine patients and 237 healthy age-, sex- and ethnicity-matched controls for the C282Y and H63D polymorphisms of the HFE gene. Phenotype and allele frequencies of both polymorphisms were similarly distributed in migraine patients and controls. The patients carrying the DD genotype of the H63D polymorphism showed a later age at onset of the disease and an increased number of migraine attacks. Our data suggest that the HFE gene is not a major disease gene for migraine. However, the H63D polymorphism of the HFE gene may be considered a modifying genetic factor in migraine.
Steering Requisites for Crises‐Opportunities: On‐Going Challenges
Authors: Dror Yehezkel
Published: October 2006

That man most luckily forms his plan, among all the persons in Fortune's palace, who chooses a wheel befitting her wish (Machiavelli, quoted in Gilbert, 1989: 747).
Symbols, Rituals and Power: The Lost Dimensions of Crisis Management
Authors: Hart Paul 't
Published: October 2006

There is a systematic deflation in governmental rhetoric of the developments that call attention to the unequal distribution of goods and services and a systematic inflation of the forms of threat that legitimize and expand authority. The latter are defined as crises, the former as problems. As crises recur and problems persist, so does a governmental dramaturgy of coping. (Edelman, 1977: 49)

This article proposes a more power‐critical approach to the analysis of crisis management and, in this respect, explores the possible contribution of research on political and organizational symbolism. Viewed in terms of symbolic action, attention is drawn to the opportunity spaces that crises entail for policy makers and other crisis actors. To exploit these, it is important for decision elites to influence collective definitions of the situation in such a way as to highlight preferred courses of action and to selectively obscure alternative interpretations. Three types of symbolic ‘crisis handling devices’ (framing, ritualization and masking) are presented and illustrated. In conclusion, the need for a broader perspective on the nature of the politics of crisis management is emphasised.
Riots in Britain and the United States: The Bureau‐Politics of Crisis Management and Urban Policy
Authors: Jacobs Brian D.
Published: October 2006

This research considers the bureaucratic politics of recent riot crisis management and urban policy in Britain and the United States.1 The bureaucratic politics model is evaluated and a tentative framework for its development as a way of analysing governmental responses to urban riots is proposed.2 The links between crisis management in riots and wider urban policy are identified as being important in developing an understanding of the nature of post‐riot policy responses within the context of the broader political environment.
Europe's Jurassic Park? NATO and the End of the Cold War1
Authors: McInnes Colin
Published: October 2006

The end of the Cold War posed a threat to NATO's continued existence: without the Soviet Union to deter, what role did NATO have? This article argues that NATO survived the immediate aftermath of the Cold War for a number of short‐term reasons, but addressed the longer‐term question of its survival primarily through changing its goals rather than its structure. In particular, it developed two new goals: a new political role involving dialogue and limited cooperation with the former Warsaw Pact states; and a capability to intervene in conflicts in Europe or elsewhere (for missions ranging from peacekeeping and humanitarian assistance to the defence of strategic interests). Both of these new roles have proved problematic, however. Although NATO's continued survival seems assured through the lack of neither a serious competitor nor any convincing reason to abandon it, its continued importance cannot be guaranteed.
Decentralization in Crisis: The Case of Everest Double Glazing Installation
Authors: Evans Jenny , James Bernard
Published: October 2006

Change and turn‐around strategies in business need to draw upon more than a literature of corporate culture for analysis and understanding. The Everest Double Glazing Company experienced an organizational transformation which precipitated rapidly into a crisis situation. The history of this case study in decentralization shows how intended management strategies aimed at change can be frustrated by complexities in behaviour and volatility in business environments. This case study brings to the fore the role of self‐inducement in the evolution of crises, questions the extent to which business organizations can prepare for crisis in their own strategic planning, and clarifies comment on the mobilizing, rather than demobilizing role of crisis in corporations. Crisis management theory contributes to the understanding of many ongoing issues that contemporary management literature seems unable to explain.
Statecraft as Prudent Risk Taking: The Case of the Middle East Peace Process
Authors: Dror Yehezkel
Published: October 2006

This article examines the problem of uncertainty and its effects upon the decision making processes of top‐level politicians. I use the Middle East Peace Process as a case to explore the handling of uncertainty in statecraft, and present a concept of statecraft as prudent risk taking, that is, carefully contemplated decisions taken with full awareness of the dangers involved as well as opportunities. I conclude by offering a set of professional approaches that may be used to improve statecraft as prudent risk taking.
Organisational Structure, Culture and Attitudes to Risk in the British Stadia Safety Industry
Authors: Frosdick Steve
Published: October 2006

The history of ‘regulation by crisis’ in the British stadia safety industry has failed to prevent successive disasters and continued near misses. To reduce the risks, there is a need to better understand why the mistakes and misunderstandings leading to such incidents actually occur. Such understanding can be informed by applying cultural theory, a method of cultural classification using ‘grid/group’ analysis and derived from social anthropology. This paper uses cultural theory to analyze ethnography from, and literature relating to, public safety risk management and British stadia disasters. The analysis reveals the conflicting risk perceptions of individualist/entrepreneurial clubs, hierarchical regulators, long‐suffering fatalist spectators and their more egalitarian colleagues in supporter and local resident pressure groups. These perceptions are narrow and biased. At a strategic level, there is a need for each constituency to acknowledge the validity of the others' points of view. Increased awareness is a key to disaster prevention. The conclusions drawn should be applicable to wider crisis scenarios where a multiplicity of organisations are involved.
Contingency Planning for Systems Evolution after Crisis: Reconstructive Brain Drain Policy‐Oriented Implications — The Case of Lebanon, 1975–1994
Authors: Helou Mammy
Published: October 2006

This paper evaluates the impact of the multinational intellectual emigration crisis, during the period 1975‐ 1994, on reconstruction policy implications and the future development of Lebanon. It analyses fundamental issues that are relevant to the study of the Lebanese brain drain crisis. The current research study presents a threefold analysis. The first section discusses a socio‐demographic trend analysis of Lebanese emigrants during the period 1975‐ 1994. In the second section, renewed brain influx policy implications and conditions are identified and evaluated through applying the Contingency Typology Simulation Heuristic approach to crisis networking and the Risk Path Analysis Model of creeping crisis multi‐level contingency schema in the context of the multinational intellectual emigration stages. Finally, the author identifies a work‐in‐progress research agenda, providing directions for future research, within the area of systems evolution, intellectual emigration and politics of multinational brain drain.
What Role to Play? Intermediaries in International Conflict as Negotiators and Facilitators
Authors: Kleiboer Marieke
Published: October 2006

Mediating Conflict: Decision‐making and Western Intervention in Namibia, V. Jabri, Manchester University Press, Manchester (1990), 198 pp.

Intermediaries in International Conflict, T. Princen, Princeton University Press, Princeton (1992) (paperback edition 1995), 263 pp.

Ending Mozambique's War: The Role of Mediation and Good Offices, C. Hume, United States Institute of Peace Press, Washington DC (1994), 162 pp.
Producing Technological Innovations
Authors: Stowers Genie N.L.
Published: October 2006

Innovation in Technology and Organization, P. Clark and N. Staunton, Routledge, London (1989), 242 pp.

Corporate Vision and Rapid Technological Change: The Evolution of Market Structure, P. Swann and J. Gill, Routledge, London (1993), 244 pp.

New Technologies and The Firm: Innovation and Competition, Edited by P. Swann, Routledge, London (1993), 383 pp.

High Technology and the Competition State: An Analysis of the Eureka Initiative, J. Peterson, Routledge, London (1993), 287 pp.
Ebola Virus: From Medical Emergency to Complex Disaster?
Authors: Benini Aldo A. , Bradford‐Benini Janet
Published: October 2006

Ebola haemorrhagic fever is a fatal disease caused by a new virus which has no known cure. Few outbreaks have been documented. Two major epidemics occurred in Africa in 1976. When a new epidemic was detected in Zaire in the spring of 1995, it was widely perceived as a threat to the West. Public attention was intense. A massive intervention, led by UN and US agencies, followed and put an end to the epidemic within less than two months.

The intervention was successful for several reasons. Effective cooperation benefitted from the network which had been initiated by virologists since the 1976 outbreak, NGO activism and international pressure. Cultural under‐currents had prepared the West for the outbreak. The prestige and competency of the international responders – particularly the UN World Health Organization and the US Centres for Disease Control and Prevention – helped to keep the emergency a simple one; amenable to a disciplined public‐health approach. Initiatives of the Zairian authorities that might have transformed it into a complex disaster were effectively amended.

A future outbreak may be harder to cope with. Unless resources are better balanced between scientific work on new viruses and grassroots organizations that play a crucial part in handling most epidemics, the current progress may be short‐lived. The next Ebola outbreak in Zaire might find the country in political turmoil. Access for public health responders may be severely limited and compounded by security and human rights issues. A complex emergency could, then, form easily.
Crises, Opportunities and Moments of Surprise: Allusions, Illusions and Disillusions
Authors: Zimmermann Ekkart
Published: October 2006

From the point of macro‐sociology and comparative politics, the collapse of communism in 1989 largely came as a surprise.1 Before further reflecting on this, first, some key concepts in comparative crisis research are briefly dealt with. Secondly, the analytical peculiarities that arise when reform from above gets out of order and mixes with challenges from below are outlined and related to the political opportunity structure approach prominent in recent and more refined research on social movements. Thirdly, is there any ‘logic’(structure) in those failures to anticipate what later, in responses to crises, came about? Fourthly, what can be learned from this for government, challengers, masses and political scientists alike? Hopefully, the paper will not create further illusions, but rather help in asking where to look, what to tackle next in research and what can be learned from the available research.
Social Aftermath and Organizational Response to a Major Disaster: The Case of the 1995 Sakhalin Earthquake in Russia
Authors: Porfiriev Boris N.
Published: October 2006

This paper explores the social consequences, and the main characteristics, of organizational response to one of the worst earthquake disasters in world history that struck Sakhalin Island, in the Far East of Russia, in Spring 1995, completely destroying one of its communities. The paper explores and uses the generic response model as an analytical framework. This model is applied to a concrete case study and the specific social environment of Russia.
Toxic Waste and Risk Prevention: Rating US Policy
Authors: Clifford Mary
Published: October 2006

Ecological Politics in an Age of Risk, Ulrich Beck, Polity Press, Cambridge (1995), 216 pp.

EcoPopulism: Toxic Waste and the Movement for Environmental Justice, Andrew Szasz, University of Minnesota Press, Minneapolis (1994), 216 pp.

Toxic Debts and the Superfund Dilemma, Harold Barnett, University of North Carolina Press, Chapel Hill (1994), 334 pp.

Beyond Superfailure: America's Toxics Policy for the 1990s, Daniel Mazmanian and David Morell, Westview Press, Boulder (1992), 278 pp.
Minimum area requirements of breeding birds in fragmented woodland of Central Argentina
Authors: Dardanelli Sebastián , Nores María Laura , Nores Manuel
Published: October 2006

The breeding avifauna of 25 woodland fragments (0.85–280 ha) was studied between 1996 and 2004 in Córdoba, Argentina. A distinctive feature of the avifauna of the fragments studied is the low area requirement of most of the species. Of the 54 woodland species recorded, 32 (59.3%) requirec. 1 ha and 43 (79.6%) needed no more than 3 ha. Also noticeable is the relatively high number of individuals of most of the species. Both characteristics suggest a good tolerance to fragmentation. However, nine species (16.7%), the area‐sensitive species, need fragments of 80 ha or larger. Moreover, eight resident species have apparently become extinct in the fragments that were studied, including the five large species that originally inhabited the area. Proportional odds and log linear models were fitted to relate the minimum area requirements of these species to various ecological characteristics (body size, diet, habitat use, migratory status, and nest type). Closed nesters, resident, woodland exterior, and medium‐size species were the groups requiring larger areas. No apparent pattern was observed between area requirements and diet. A recent law prohibits woodland removal, which is a positive step towards the conservation of the fragments. The results suggest that as long as the present amount of woodland is maintained, the situation of the avifauna of the fragments is relatively secure, at least in the short term.
Resolving the native provenance of invasive fireweed (Senecio madagascariensis Poir.) in the Hawaiian Islands as inferred from phylogenetic analysis
Authors: Le Roux Johannes J. , Wieczorek Ania M. , Ramadan Mohsen M. , Tran Carol T.
Published: October 2006

Accurate identification of weedy species is critical to the success of biological control programs seeking host‐specific control agents. Phylogenetic relationships based on internal transcribed spacer region (ITS1, ITS2) DNA sequence data were used to elucidate the most likely origin and taxonomic placement of Senecio madagascariensis Poir. (fireweed; Asteraceae) in the Hawaiian archipelago. Putative S. madagascariensis populations from Madagascar, South Africa, Swaziland, and Hawaii were included in the analysis. Different phylogenetic models (maximum parsimony and maximum likelihood) were congruent in suggesting that Hawaiian fireweed is most closely related to populations from the KwaZulu‐Natal region in South Africa. Phylogenetic divergence and morphological data (achene characteristics) suggest that the S. madagascariensis complex is in need of revised alpha‐level taxonomy. Taxonomic identity of invasive fireweed in Hawaii is important for finding effective biological control agents as native range populations constitute different biotypic variants across a wide geographical area. Based on our phylogenetic results, research directed at biological control of Hawaiian infestations should focus on areas in the KwaZulu‐Natal region in South Africa where host‐specific natural enemies are most likely to be found. Our results show that phylogeographical analysis is a potential powerful and efficient tool to address questions relevant to invasion biology of plants.
Dispersal as a key element of community structure: the case of ground beetles on lake islands
Authors: Zalewski Marcin , Ulrich Werner
Published: October 2006

In order to study the influence of dispersal ability on community structure of ground beetles (carabidae), 15 lake islands and 2 mainland sites of the lake Mamry archipelago, northern Poland, were sampled by using pitfall traps. Of the 71 ground beetle species detected, 47 were macropterous, 16 wing‐dimorphic and 8 brachypterous. Macropterous species had lower site abundances and occupied fewer sites than dimorphic and brachypterous species. There were trends from macropterous to brachypterous species towards a nested distribution across the sites and towards over‐dispersed (aggregated) species co‐occurrences. Canonical correspondence analysis pointed to site isolation and area as main factors influencing site abundance and spatial distribution. Our results imply that further studies on species co‐occurrences and community assembly have to consider dispersal ability as a key element influencing ecological distributions at the regional scale.
Combining phylogenetic and ecological niche modeling approaches to determine distribution and historical biogeography of Black Hills mountain snails (Oreohelicidae)
Authors: Weaver Kathleen F. , Anderson Tamara , Guralnick Robert
Published: October 2006

We aim to show how a combination of molecular systematics and ecological niche modelling approaches can be used to test historical biogeographical hypotheses for species of conservation concern. We focus on the land snail genus Oreohelix (Oreohelicidae), a group found throughout the Rocky Mountains. In addition to its larger distribution, a group of Oreohelix is also found in the Black Hills of Wyoming and South Dakota, an isolated, easternmost extension of the Rocky Mountains. We determine the number, distribution, and relationships of Black Hills Oreohelicids, which are a current conservation concern due to their fragmented distribution. We compared Black Hills groups to those in the main part of the Rockies to test historical biogeographical patterns that explain current diversity. We collected mtDNA data (COI and 12S sequences) from multiple populations of Oreohelix throughout the Black Hills and in adjacent populations in the Rocky Mountains to construct phylogenetic hypotheses. To determine whether favourable environmental conditions currently exist between the Black Hills and the north‐eastern Rocky Mountains, we used DesktopGARP to generate an ecological niche model for distinct lineages discovered in the molecular phylogenetic analysis. Results show that all Black Hills populations are likely Oreohelix cooperi and that little genetic differentiation exists within this clade. In addition, Black Hills groups are genetically similar or identical to populations found in the Judith Mountains and Bighorn Mountains (north‐eastern Rockies). Ecological niche models show that suitable environmental conditions may exist between eastern Rockies and Black Hills O. cooperi samples. Taken together, the phylogenetic and niche model data, along with the low vagility of the snails, support passive long‐distance dispersal as a likely explanation for current arrangement of biodiversity.
Variation in peak P–T conditions across the upper contact of the UHP terrane, Dabieshan, China: gradational or abrupt?
Authors: SHI Y. , WANG Q.
Published: October 2006

The Southern Dabieshan Terrane (SDT) has previously been divided into high‐pressure (HP) and ultrahigh‐pressure (UHP) terranes, and its regional extent and the tectonic nature of its boundaries are hotly debated topics. In this study, an eclogite‐bearing area of 100 km2 near Taihu is mapped in detail, and divided into Northern, Middle and Southern Zones on the basis of lithological characteristics. The Northern Zone consists of epidote‐biotite gneiss and eclogite blocks, the Middle Zone includes granitic gneiss, biotite gneiss, eclogites and amphibolite, and the Southern Zone is composed mainly of garnet‐bearing mica schist. The eclogites occur mainly as lens or blocks in the Northern and Middle Zones. The peak P–T conditions for 61 eclogite samples across the area are estimated using the Grt‐Cpx Fe2+‐Mg thermometers and the Grt‐Cpx‐Phe barometers. The results indicate three different P–T regions: 2.82–4.09 GPa/759–942 °C in the Northern Zone, and 2.00–3.54 GPa/641–839 °C in the granitic gneiss and 1.38–2.36 GPa/535–768 °C in the biotite gneiss from the Middle Zone. Combined with the spatial distribution of eclogites across the area, the P–T values for eclogites increase continuously from the south to the north, defining a reference ‘geotherm’ of 5 °C km−1. However, some unreasonable apparent gradients can be established along two south–north profiles across the area, and display a P–T difference between the Northern and Middle zones. On the basis of the average P–T data for eclogites across the area, a gap of at least 0.3 GPa/20 °C exists between the Northern and Middle zones. By contrast, the P–T values of eclogites from the Middle zone show a coherent pattern with transitional characteristics from HP in the south to UHP in the north. We suggest that the SDT was a coherent slab during subduction, and was broken up by a major fault during exhumation, which was formed under UHP metamorphic conditions.
Pharmacology of Dihydroergotamine and Evidence for Efficacy and Safety in Migraine
Authors: Saper Joel R. , Silberstein Stephen
Published: October 2006

Dihydroergotamine mesylate (DHE), an ergot alkaloid, has been extensively utilized and studied in the treatment of episodic and chronic migraine. This article reviews the pharmacokinetics, pharmacodynamics, and clinical efficacy and safety of DHE, particularly in comparison to ergotamine tartrate (ET), a similar ergot alkaloid with a long history of use in the treatment of migraine. Structural differences between these 2 compounds account for clinically important distinctions in their pharmacokinetic, pharmacodynamic, and adverse event profiles. DHE is a significantly less potent arterioconstrictor than is ET, which makes it a potentially much safer drug. In addition, DHE is associated with a markedly lower incidence of medication‐withdrawal headache, nausea, and vomiting than is ET. The safety and efficacy data presented here are derived from clinical trials and case series involving DHE administered by intravenous infusion, intramuscular or subcutaneous injection, or intranasal spray.
Central Sensitization Theory of Migraine: Clinical Implications
Authors: Dodick David , Silberstein Stephen
Published: October 2006

The clinical science of migraine headache continues to evolve. Theories of the pathophysiology of migraine have progressed from the early vascular basis of migraine to more complex current theories that emphasize the centrality of neuronal dysfunction. The most recently articulated theory of migraine is the central sensitization hypothesis, which proposes that altered processing of sensory input in the brainstem, principally the trigeminal nucleus caudalis, could account for many of the temporal and symptomatic features of migraine, as well as its poor response to triptan therapy when such treatment is initiated hours after the onset of pain. Both preclinical and clinical data support the central sensitization theory. A critical clinical implication of this theory is that drugs that are capable of either aborting or arresting the process of central sensitization, most prominently dihydroergotamine, may have a unique role in the treatment of migraine. An additional, and highly practical, implication is based upon the finding that cutaneous allodynia—pain arising from innocuous stimulation of the skin, as in hair brushing or the application of cosmetics—is an easily identifiable marker of central sensitization. Thus, the presence or absence of cutaneous allodynia can be integrated into the routine clinical assessment of migraine and utilized as a determinant of treatment. Future basic and clinical research on central sensitization is likely to be of ongoing importance to the field.
Nasal Delivery of Antimigraine Drugs: Clinical Rationale and Evidence Base
Authors: Rapoport Alan , Winner Paul
Published: October 2006

The intranasal route of administration for antimigraine drugs offers many theoretical and practical advantages. A drug that is administered intranasally is absorbed by the highly vascular mucous membranes of the nose, which allows for rapid delivery of un‐metabolized drug to the central nervous system. The onset of action is thus considerably earlier than with oral administration requiring gastrointestinal absorption. The intranasal route also provides several practical advantages, such as greater acceptability to patients because of the noninvasive mode of delivery, the ability to take medication when severe nausea or vomiting is present, and a better adverse event profile. Three antimigraine drugs are available in intranasal formulation: dihydroergotamine, sumatriptan, and zolmitriptan. This article reviews the pharmacology, efficacy, safety, and tolerability of these agents. All are well tolerated by patients and have demonstrated efficacy in the treatment of migraine headache. Each of these drugs has a unique pharmacokinetic and pharmacodynamic profile, which may support a clinical preference for one intranasal agent over another in treating patients with specific headache features.
Enhanced ascertainment of microchimerism with real‐time quantitative polymerase chain reaction amplification of insertion‐deletion polymorphisms
Authors: Lee Tzong‐Hae , Chafets Daniel M. , Reed William , Wen Li , Yang Yunting , Chen Jennifer , Utter Garth H. , Owings John T. , Busch Michael P.
Published: October 2006

BACKGROUND: The characterization of microchimerism (MC) by gene amplification has been limited by few allogeneic markers, ascertainment bias, and assay analytic performance. To address this, a panel of 12 MC assays based on insertion‐deletion (InDel) polymorphisms had been optimized.

STUDY DESIGN AND METHODS: The InDel assays were validated with comprehensive in vitro spiking studies at the stochastic limit of detection. Their ability was also determined to ascertain MC of unknown source genotype with both theoretical and actual donor‐recipient pairs, and the assays were applied to a clinical population of 73 trauma patients who received transfusions where MC was previously characterized by HLA‐based assays alone.

RESULTS: In the stochastic spiking experiments, all assays were sensitive to a single copy of target DNA, and no false‐positive amplification occurred among 1128 samples studied. Among 219 theoretical donor‐recipient pairs, informative alleles existed for 99.5 percent with both InDel and HLA compared to 91.3 percent with HLA alone. In the clinical population, 33 cases of MC were detected (9 more cases than by HLA‐DR alone) in the nonleukoreduced (non‐LR) group and 8 cases (1 more case than by HLA‐DR) in the LR group for the short‐term follow‐up. Among 27 long‐term follow‐up samples, 8 cases were detected overall (3 more cases than by HLA‐DR alone).

CONCLUSION: It is concluded that an InDel‐based assay panel has excellent technical performance characteristics while also allowing for ascertainment of some MC cases not detectable with HLA alone. The tandem use of both the InDel and the HLA provides a powerful tool for the enhanced ascertainment of MC.
Resistance of porcine circovirus and chicken anemia virus to virus inactivation procedures used for blood products
Authors: Welch Jon , Bienek Carol , Gomperts Edward , Simmonds Peter
Published: October 2006

BACKGROUND:Virus inactivation procedures are used to prevent contamination of plasma‐derived blood products with viruses. Pasteurization or prolonged dry heat has proven effective against several enveloped and nonenveloped viruses and provides an additional layer of safety for plasma products.

STUDY DESIGN AND METHODS:The resistance of porcine circovirus 2 (PCV2) and chicken anemia virus (CAV), two small, nonenveloped viruses, to standard (pasteurization, 10 hr at 60°C; dry heating, 80°C for 72 hr) and more extreme heat inactivation procedures (temperatures up to 120°C) was determined. The ability of these procedures to inactivate PCV2 and CAV was measured by comparison of in vitro infectivity before and after treatment.

RESULTS:Infectivity of PCV2 and CAV was reduced by approximately 1.6 and 1.4 log by pasteurization and by 0.75 and 1.25 log by dry‐heat treatment, both substantially more resistant than other viruses previously investigated. PCV2 and CAV were additionally almost completely resistant to dry‐heat treatment up to 120°C for 30 minutes (mean log infectivity reductions, 1.25 and 0.6), although both were more effectively inactivated when the temperature of wet‐heat treatment was increased to 80°C (>3.2 and >3.6 log infectivity reduction).

CONCLUSION:Although neither PCV2 nor CAV are known to infect humans, their inactivation properties may represent those of other small DNA viruses known to be present (e.g., TT virus, small anellovirus) or potentially present in human plasma. Findings of extreme thermal resistance demonstrate that recipients of plasma‐derived therapeutics may potentially still be exposed to small DNA viruses, despite the implementation of viral inactivation steps.
Dispermic chimerism identified during blood group determination and HLA typing
Authors: Mosebach Mira , Parkner Andreas , Jakubiczka Sybille , Wieacker Peter , Heim Marcell U.
Published: October 2006

BACKGROUND: Chimerism is the presence of two or more genetically distinct cell populations in one organism.

STUDY DESIGN AND METHODS: We report the identification of dispermic chimerism in a 19‐year‐old female volunteer blood donor. During routine ABO blood grouping strong reactions of the blood donors red blood cells (RBCs) with anti‐A reagents and mixed‐field reactions with anti‐B reagents were observed, while serum‐testing showed the absence of anti‐A and anti‐B antibodies. AB0 blood group genotyping, HLA‐typing and microsatellite analysis were performed using blood‐samples, buccal mucosa and fibroblasts of the blood‐donor and blood‐samples of her parents.

RESULTS: AB0 blood group genotyping showed three ABO blood group alleles (01, A2 and B) in the DNA‐samples of the blood‐donor. The evidence of chimerism was supported by the detection of three alleles for the HLA‐A and HLA‐DRB1 loci. Microsatellite analysis with ten markers revealed three alleles for loci D7S821 and D19S412. All studies carried out, the third allele was always of paternal origin.

CONCLISION: The results suggested a case of a human dispermic chimerism. Our proposed explanation for the development of chimerism in the reported case is the fertilization of an oocyte and the corresponding second polar body by two different sperms.
Changes in Autonomic Activity Preceding Onset of Nonsustained Ventricular Tachycardia
Authors: Osaka Motohisa , Saitoh Hirokazu , Sasabe Noriko , Atarashi Hirotsugu , Katoh Takao , Hayakawa Hirokazu , Cohen Richard J.
Published: October 2006

Background: The triggering role of the autonomic nervous system in the initiation of ventricular tachycardia has not been established. To investigate the relationship between changes in autonomic activity and the occurrence of nonsustained ventricular tachycardia (NSVT) we examined heart rate variability (HRV) during the 2‐hour period preceding spontaneous episodes of NSVT. Twenty‐four subjects were identified retrospectively as having had one episode of NSVT during 24‐hour Holter ECG recording.

Methods: We measured the mean interval between normal beats (meanRR), the standard deviation of the intervals between beats (SD), the percentage of counts of sequential intervals between normal beats with a change of >50 ms (%RR50), the logarithms of low‐ and high‐frequency spectral components (InLF, InHF) of HRV for sequential 10‐minute segments preceding NSVT. The correlation dimension (CDim) of HRV was calculated similarly for sequential 20‐minute segments. We assessed the significance of the time‐course change of each marker over the 120‐minute period prior to NSVT onset.

Results: MeanRR (P < 0.05), InLF (P < 0.0001), InHF (P < 0.0001), the natural logarithm of the ratio of LF to HF (ln[LF/HF]; P < 0.05), and CDim (P < 0.05) showed significant time‐course changes during that period, while SD and %RR50 did not. MeanRR, InLF, InHF, and CDim all decreased prior to the onset of NSVT, whereas ln(LF/HF) increased. We divided the subjects into two groups: one consisting of 12 patients with coronary artery disease; and the second group of 12 patients without known coronary artery disease. Both groups showed significant changes (P < 0.05) of CDim, InLF, and InHF preceding the episodes of NSVT.

Conclusions: Changes in the pattern of HRV prior to the onset of episodes of NSVT suggest that changes in autonomic activity may commonly play a role in the triggering of spontaneous episodes of NSVT in susceptible patients. The measured changes suggest a reduction in parasympathetic activity, perhaps in conjunction with an increase in sympathetic activity, may trigger NSVT.
A hundred years of progress in electrocardiography 1: Early contributions from Waller to Wilson
Authors: Raltaharju Pentti M.
Published: October 2006

ABSTRACT: The 1887 introduction of electrocardiography as a noninvasive investigative technique on man by Augustus Waller, and Wilhelm Einthoven's electrocardiograph from 1901 remain the two major landmarks in the 100‐year history of electrocardiography. The progress in our knowledge of the mechanism and interpretation of the ECG hasevolved throughout these 100 years in a succession of relatively small steps contributed by many unsung heroes, although often even relatively minor contributions by a few dominant 'stars notably Thomas Lewis and Frank Wilson, are perceived as giant leaps. The gradual evolution of our concepts of the ECG are reviewed against the historical background of the events involved from the time of Waller's discovery to the end of the second world war.
Electrocardiographic Self‐Recording (Patient‐Activated Event Recording)
Authors: Steinbach Konrad , Nümberg Michael , Wessely Emil
Published: October 2006

Background: Although symptoms suggestive of cardiac arrhythmias are a common event in clinical routine, a standardized diagnostic approach is not available.

Methods: The diagnostic accuracy of electrocardiographic self‐recording was evaluated in 115 consecutive patients presenting with symptoms suggestive of cardiac arrhythmias.

Results: In 44.3% of cases, self‐recording showed cardiac arrhythmias to be the cause of the patients' symptoms; in 35.7% cardiac arrhythmias were ruled out as the cause of the patients' symptoms. Only 6.2% of the recordings were not evaluable for technical reasons.

Conclusion: ECG self‐recording is more effective in detecting arrhythmias than other methods for arrhythmia monitoring. Therefore, it should be used as a first line study in patients likely to have symptomatic arrhythmias.
Spectral Analysis of the High Resolution QRS Complex During Exercise‐Induced Ischemia
Authors: Beker Amir , Erel Jacob , Pinchas Abraham , Abboud Shimon
Published: October 2006

Background: The effect of acute myocardial infarction and regional ischemia on the frequency content of the ECG signal has been described by several investigators. In the present study, the feasibility of assessing changes in the QRS spectrum during exercise testing, and whether these changes are related to the occurrence of ischemia were examined.

Methods: Spectral analysis of the high resolution ECGs from leads V3, V4, V5, and V6 were performed in two groups of male subjects before, during, and following treadmill exercise testing. Group A included 32 coronary artery disease (CAD) patients, with arteriographically proven >75% obstruction of at least two main coronary arteries, and group B included 30 healthy subjects, without history or symptoms of CAD. Signal averaging and filtering techniques were used in order to enhance the signal‐to‐noise ratio of the recorded ECGs. The power spectrum of the averaged QRS waveform for the different stages of the exercise testing was computed using a Fast Fourier Transform, and the slope of the linear regression line was found in the frequency range 7.81–249.92 Hz on the plot of log((amplitude)2) versus log(frequency).

Results: Regression line slopes immediately after peak exercise were significantly lower for the CAD group than for the healthy subjects in 3 of the 4 examined leads. No significant changes in slopes were found between the two groups at rest or during late recovery. Comparing the differences between slopes at different stages of the test revealed that the difference between postexercise slope and rest slope has lower mean values for the CAD group in all four leads, with a significant difference in lead V6, and for the difference between postexercise slope and recovery slope, lower mean values were found for the CAD group in all four leads, with a significant difference in V5 and V6.

Conclusions: These findings indicate that ischemic changes affect the power spectrum of the QRS complex, and result in a steeper regression line on a log‐log scale.
Beneficial Effects of Captopril and Metoprolol Treatment in Idiopathic Dilated Cardiomyopathy
Authors: Tomita Fumishi , Kohya Tetsuro , Kaji Tohru , Tsuzuki Noriko , Ono Tomohide , Itoh Yoshinori , Sasaki Motoi , Kitabatake Akira
Published: October 2006

Background: Abnormal autonomic nervous function (ANF), such as an enhanced sympathetic tone and an attenuated parasympathetic tone, have been shown in patients with congestive heart failure (CHF).

Methods: We examined the effects of captopril and metoprolol on autonomic nervous function and ventricular arrhythmias in patients with idiopathic dilated cardiomyopathy (DCM), using 24‐hour ambulatory electrocardiographic monitoring and power spectral analysis of heart rate variability. Twenty‐one patients (pts) with idiopathic DCM (54 ± 15 years [mean ± SDI) were allocated to three groups: a captopril group (8 pts); a metoprolol group (7 pts); and a control group (6 pts). Power spectra were quantified in high (HF) and low frequency power (LF), and natural logarithmic values of HF (In(HF) and LF/HF (In (LF(HF]) were used as indices of parasympathetic and sympathetic nervous activities, respectively.

Results: In the captopril and the metoprolol groups, there was a significant increase in In(HF) (P < 0.05), a trend of decrease in ln(LF/HF), and an improvement of ventricular arrhythmia (VA). In contrast, no significant change was found in any of In(HF), In (LF/HF), and VA in the control group.

Conclusion: We conclude that both captopril and metoprolol have beneficial effects on ANF and VA, and the restored autonomic balance and the improvement of VA correlate to each other.
Disturbed Autonomic Activity Precedes Ischemic Episodes in Patients with Variant Angina
Authors: Kubota Naokuni , Lee Jong‐Dae , Shimizu Hiromasa , Tsubokawa Akiyoshi , Ueda Takanori
Published: October 2006

Background

While the autonomic nervous system is known to be involved in the pathogenesis of variant angina, the relationship between disturbed autonomic activity and ischemic episodes in patients with variant angina has not been determined.

Methods

We performed 24‐hour Holter monitoring and power spectral analysis of heart rate variability (HRV) in ten patients with variant angina. The low frequency (0.04–0.15 Hz [LF]) and high frequency (0.15–0.40 Hz [HF]) components of HRV were quantified. The ratio of LF to HF (LF/HF) and the coefficient of the RR interval variation (CV) were also calculated. We analyzed HRV every 10 minutes beginning 50 minutes before the onset of ischemic episodes confirmed by ST segment elevation.

Results

The LF/HF from 40 to 30 minutes before ischemia was decreased compared with the value from 50 to 40 minutes before ischemia (0.80 ± 0.15 vs 1.63 ± 0.44, mean ± SE, P = 0.037). The LF/HF then began to increase, and the value from 20 to 10 minutes (2.91 ± 0.66) was significantly greater than that from 40 to 30 minutes (P < 0.01). The CV was increased from 30 to 20 minutes before ischemia compared with the CV from 50 to 40 minutes (8.5%± 1.6% vs 5.2%± 0.8%, P = 0.033). The LF/HF and the CV remained increased until the onset of ischemia.

Conclusions

Data suggests that a disturbed autonomic nervous activity plays an important role in the initiation of coronary vasospasm in patients with variant angina. A.N.E. 1997;2(4):313–318
The Outcome of Exercise Tolerance Testing is Dependent on the Time of the Day
Authors: de Vries Rob J. M. , Witting Wil , van Veldhuisen Dirk J. , de Kam Pieter J. , Crijns Harry J.G.M.
Published: October 2006

Background

Although exercise testing is commonly used to identify patients with an increased risk for ischemic events and to evaluate drug therapy, no reports have clearly addressed whether a daily variation exists in exercise test parameters. Therefore the present study was undertaken, analyzing the effects of the time of the day on exercise test parameters in a large population of cardiovascular patients.

Methods

We compared the responses of bicycle exercise testing in 6674 patients, mean age 60 years, referred for evaluation of coronary artery disease. The daily variation was tested by grouping the exercise variables into four 2‐hour periods. Further logistic regression analysis was used to assess predictors for the occurrence of ischemia.

Results

Significant time of the day differences were found both at rest and in their changes to peak exercise for heart rate (P < 0.0001 and P < 0.0004), systolic blood pressure (P < 0.0001 and P < 0.0003), and diastolic blood pressure (P < 0.004 and P < 0.0001). Furthermore, ischemia occurred significantly more often during the afternoon intervals (P < 0.009) and time of the day was an independent predictor of ischemia during exercise testing.

Conclusion

The present study demonstrates that several exercise parameters show a significant daytime variation. The time of the day is an independent predictor for the occurrence of ischemia during an exercise test, and the detection of ischemia may be enhanced by performing exercise tests in the afternoon.
Heart Rate Variability Early After Successful Radiofrequency Catheter Ablation of Left‐ and Right‐Sided Accessory Pathways and After Selective Ablation of the Slow Pathway
Authors: Sztajzel Juan M. , Vinolas Xavier , Sobral José , Dumaresq Lucia , Boveda Serge , Torner Pelayo , Oter Ramon , de Luna Antonio Bayés
Published: October 2006

Background

Inappropriate sinus tachycardia (1ST) and alterations in heart rate variability (HRV) may survene after radiofrequency catheter ablation (RFCA). The objective of this study was to analyze and to compare HRV after RFCA of supraventricular tachycardia.

Methods

HRV components were analyzed and compared in 86 patients early after successful RFCA of left‐sided (LSAP) (n = 38) and right‐sided (RSAP) accessory pathways (n = 18), and after selective ablation of the slow atrioventricular nodal pathway (n = 30). All HRV parameters, including indices of time‐domain, 24‐hour RR histogram, and power spectral analysis, were obtained from Holler tapes recorded 24–48 hours after RFCA, free of antiarrhythmic drugs.

Results

We found a significant increase in mean heart rate and significant reductions in most indices of time domain in patients of the slow pathway >SP) group when comparing to the two other groups. 1ST was found in 7% of patients. The plot of the 24‐hour RR histogram and the frequency‐domain analysis, demonstrated the same tendency to significantly lower values in patients of the SP group. Values of r‐MSSD and pNN5O were significantly reduced in patients of the RSAP group, most (72%) of posteroseptal (PS) location, in comparison with values observed in patients of the LSAP group.

Conclusions

In our study, comparisons between postablation HRV indices of the three groups suggest a decrease of the sympathetic and parasympathetic components in patients of the SP group, probably due to autonomous fiber damage. Ablation in patients of the RSAP group, most of PS location, shows an attenuation of the predominantly parasympathetic component, probably in relation to the anatomical site of the PS pathways, and indicates thereby an intermediate behavior of this type of pathway.