bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation of killer cell immunoglobulin‐like receptors gene KIR3DL2 diversity and confirmation of KIR3DL2*015 in a Chinese population
Authors: Yan L.‐X. , Zhu F.‐M. , Jiang K , Lv Q.‐F. , He J.‐J.
Published: September 2006

Human killer cell immunoglobulin‐like receptors (KIRs) are a subfamily of the immunoglobulin superfamily. Here, we established polymerase chain reaction–sequence‐based typing (PCR‐SBT) procedure to identify alleles of KIR3DL2 gene. The method was designed around the specific amplification of exon 3 to exon 4 and exon 8 to exon 9 of the KIR3DL2 gene. Genomic DNA from 104 healthy, unrelated Chinese Han individuals was typed for KIR3DL2 alleles. Each sample was assigned to the putative allele combination according to the sequences of all KIR3DL2 alleles. We observed 18 different genotypes and eight KIR3DL2 alleles in the population, with KIR3DL2*002 having the highest frequency of 0.558, and confirmed the new KIR3DL2*015 allele. Our data showed that the established PCR‐SBT methods for KIR3DL2 allele typing were reliable, and Chinese Han population is distinct in KIR3DL2 allele frequencies.
Development of multiple sclerosis after vaccination against hepatitis B: a study based on human leucocyte antigen haplotypes
Authors: Özakbas S. , Idiman E. , Yulug B. , Pakoz B. , Bahar H. , Gulay Z.
Published: September 2006

The aetiology of multiple sclerosis (MS) is still not fully understood. Infectious agents are believed to play a role in the development of this multifactorial disease. Cases in which this disease occurs after administration of both plasma‐derived and recombinant hepatitis B vaccines have been reported. In this study, we compared a group of 11 MS patients who developed first clinical symptoms after hepatitis B vaccination (group I) with 71 MS patients who were never vaccinated against hepatitis B and were negative for hepatitis B serology (group II), and 20 healthy controls (group III). Mean age was 27.75 years (19–39) in group I, 30.16 years (18–50) in group II, and 34.4 years (18–50) in group III. Mean attack rate after 2 years was 1.5 in group I and 1.63 in group II. Mean Expanded Disability Status Scale score after 2 years was 1.31 in group I and 1.89 in group II. Human leucocyte antigen (HLA) typing and serology for hepatitis B surface antigen were performed in all groups. In groups I and II, HLA‐DR2 was more frequent than in normal healthy subjects. This reflects the general role of HLA in the pathogenesis of MS but suggests that antigen presentation by different HLA is not involved in the development of MS after hepatitis B vaccination. Since there was no difference in the clinical features between vaccinated and nonvaccinated MS patients, this study supports recent reports that hepatitis B vaccination is safe in MS patients and that hepatitis B vaccination is not involved in the development of MS.
Identification of the new allele B*3556 and extension of the sequences of B*4420 and B*4427†
Authors: Voorter C. E. M. , Gervais T , Mulkers E. M. T. , Latinne D. , Van Den Berg‐Loonen E. M.
Published: September 2006

A new B*35 allele, B*3556, was identified in a Caucasian individual. Direct sequencing of exons 2 and 3 revealed that B*3556 was identical to B*3503, except for a nucleotide substitution from G to A at position 302, which causes a change from AGC to AAC at codon 101. This results in an amino acid change from Ser to Asn at position 77 of the mature protein. Two B*44 alleles, B*4420 and B*4427, were detected in a liver recipient and in an unrelated bone marrow donor, respectively, and their sequences were confirmed. The sequences of exons 1,4 and 5 were also elucidated; for B*4420, these exons proved to be identical to those of B*440201. The sequence of exon 5 of B*4427 showed three mismatches with that of B*440201, implicating that it probably arose from B*440201 by allele conversion with an allele of the B*15, 45, 46, 49 or 50 allele group. Elucidation of the sequence of introns 3 and 4 indicated that the breakpoint for allele conversion has to be located in intron 3 or exon 4.
Humanized transgenic mice expressing HLA DR4‐DQ3 haplotype: reconstitution of phenotype and HLA‐restricted T‐cell responses
Authors: Chen Z. , De Kauwe A. L. , Keech C. , Wijburg O. , Simpfendorfer K. , Alexander W. S. , McCluskey J.
Published: September 2006

Many autoimmune conditions have close genetic linkages to particular human histocompatibility leukocyte antigen (HLA) class II genes. With the aim of establishing a murine model of autoimmune disease, we have generated an HLA DR4‐DQ3 haplotype transgenic (Tg) mouse that expresses a 440‐kb yeast artificial chromosome harbouring DRA, DRB1*040101, DRB4*010301, DQA1*030101, DQB1*0302 and all the internal regulatory segments. This Tg mouse line was crossed to human CD4 (hCD4) Tg mice and endogenous class II knockout mice (I‐Ao/o and I‐Eo/o) lines to generate a DR4‐DQ3.hCD4.IAEo/o Tg line. The Tg DR and DQ molecules are expressed on the physiological cell types in these animals, i.e. on most B cells (>85%), dendritic cells (DCs) and macrophages but not on T cells, with levels of expression comparable with those of human B cells (where DR > DQ expression). The DR4/DQ3 transgenes fully reconstituted the CD4 T‐cell compartment, in both the thymus and the periphery, and the analysis of the T‐cell receptor repertoire in the Tg mice confirmed that these class II molecules were able to mediate thymic selection of a broad range of Vβ families. HLA DR4‐ and DQ3‐restricted T‐cell responses were elicited following immunization with known T‐cell determinants presented by these molecules. Furthermore, the DR4‐DQ3‐restricted CD4+ T cells conferred protective antibody‐mediated immunity against an otherwise lethal infection with Salmonella enterica var. typhimurium. These new DR4‐DQ3 Tg mice should prove to be valuable tools for dissecting the importance of this class II haplotype in autoimmune disorders like rheumatoid arthritis.
Twenty‐three novel HLA‐B alleles identified during intermediate‐resolution testing
Authors: Lazaro A. M. , Cao K. , Masaberg C. , Steiner N. K. , Xiao Y. , Tu B. , Turner V. , Nickerson P. , Stoll S. , Schall C. , Valdez R. , Ng J. , Hartzman R. J. , Hurley C. K.
Published: September 2006

Twenty‐three novel human leukocyte antigen‐B alleles are described: B*070204, *0738, *0742, *0821, *130202, *1312, *1575, *1598, *1599, *270507, *2728, *350104, *3558, *3811, *3931, *3932, *4045, *4107, *420501, *4812, *510106, *5520, and *5616. Thirteen of the variants are single‐nucleotide substitutions from their most homologous allele, eight resulting in amino acid changes (B*0742, *1312, *1598, *1599, *3558, *3931, *4107, and *5616) and five with silent substitutions (B*070204, *130202, *270507, *350104, and *510106). Three alleles (B*0738, *4812, and *5520) differ by five nucleotide changes, altering four amino acids. The remaining seven alleles differ from their most similar alleles by two to three nucleotides, altering from one to two amino acids.
Human leucocyte antigen class II polymorphism in Irish patients with multiple sclerosis
Authors: Dunne C. , McGuigan C. , Crowley J. , Hagan R. , Rooney G. , Kelleher J. , Hutchinson M. , Lawlor E.
Published: September 2006

The contribution of human leucocyte antigen (HLA) to the genetic risk for multiple sclerosis (MS) in patients of Northern European Caucasoid ancestry has been known since the 1970s. The northern part of Ireland, including county Donegal, is known to be a high‐risk area for the development of MS. Recorded prevalence rates for county Wexford in the south‐east Ireland have been markedly lower and suggest the existence of a prevalence gradient within the island. To evaluate the association of HLA‐DRB1 and ‐DQB1 haplotypes with MS in both Wexford and Donegal, we examined a total of 118 patients and 400 regionally matched controls. The aim of this exploratory study was to test the possibility of heterogeneity in HLA class II associations with MS and to identify potential predisposing or protective haplotypes, associated with MS risk in Ireland. We confirmed the association of DRB1*1501‐DQB1*0602 haplotype carriage with MS in both Wexford [odds ratio (OR) = 2.95, P= 0.0020, Pcor= 0.0220] and Donegal (OR = 2.29, P= 0.0030, Pcor= 0.0420). A higher frequency and a significantly higher homozygosity rate of this haplotype in Donegal are likely contributing factors to the higher prevalence of MS in Donegal compared with Wexford. The distribution of HLA class II alleles among Irish MS patients and controls establishes that there is heterogeneity in HLA class II associations with MS within Ireland.
Sex ratio variance and the maintenance of environmental sex determination
Authors: FREEDBERG S. , TAYLOR D. R.
Published: September 2006

Although variation in population sex ratios is predicted to increase the extinction rate of clades with environmental sex determination (ESD), ESD is still seen in a wide array of natural systems. It is unclear how this common sex‐determining system has persisted despite this inherent disadvantage associated with ESD. We use simulation modelling to examine the effect of the sex ratio variance caused by ESD on population colonization and establishment. We find that an accelerating function of establishment success on initial population sex ratio favours a system that produces variance in sex ratios over one that consistently produces even sex ratios. This sex ratio variance causes ESD to be favoured over genetic sex determination, even when the mean global sex ratio under both sex‐determining systems is the same. Data from ESD populations suggest that the increase in population establishment can more than offset the increased risk of extinction associated with temporal fluctuations in the sex ratio. These findings demonstrate that selection in natural systems can favour increased variance in a trait, irrespective of the mean trait value. Our results indicate that sex ratio variation may provide an advantage to species with ESD, and may help explain the widespread existence of this sex‐determining system.
Hybridization and reproductive isolation among syntopic populations of the topminnows Fundulus notatus and F. olivaceus
Authors: DUVERNELL D. D. , SCHAEFER J. F. , HANCKS D. C. , FONOTI J. A. , RAVANELLI A. M.
Published: September 2006

Fundulus notatus and Fundulus olivaceus are two closely related topminnow species that exhibit similar ecological niches and broad, largely overlapping, North American ranges extending throughout much of the Mississippi River drainage as well as the coastal drainages of the Gulf of Mexico. Previous studies have suggested that these two species are reproductively compatible despite cytogenetic differences and will hybridize when syntopic. We used nuclear and mtDNA loci to assess levels of hybridization and test for introgression in syntopic populations of these two species in four drainages in southern Illinois. Although hybridization was detected in all syntopic populations, an assessment of the proportion of hybrid individuals indicated a deficiency of hybrids relative to expectations under random mating. We determined that, although mtDNA introgression was prevalent and extended beyond the zones of contact, evidence of nuclear introgression was limited to the zone of sympatry.
Active compounds in Populus nigra L. wilted leaves responsible for attracting Helicoverpa armigera (Hübner) (Lep., Noctuidae) and new agaropectin formulation
Authors: Li W.‐Z. , Yuan G.‐H. , Sheng C.‐F. , Guo X.‐R.
Published: September 2006

Abstract:  The leaf extracts of Populus nigra were collected and identified by steam distillation, air entrainment and gas chromatographic–mass spectrometric analysis. Electroantennograms were recorded from Helicoverpa armigera adults in response to the chemicals identified. Both aromatic compounds and green‐leaf volatiles elicited strong responses. Field experiments revealed that the active compounds responsible for attracting H. armigera moths are mainly short‐side‐chain aromatic alcohols and aldehydes. We, for the first time, used agaropectin as the controlled‐release matrix of insect attractants. A five‐component lure containing all the aromatics without phenolics, mixed in the proportions as found in the steam distillate of the leaves collected in August, produced the best trap catch. The results showed that the volatiles of wilted leaves of P. nigra can attract H. armigera adults by feeding attraction.
Effects of different application methods of azadirachtin against sweetpotato whitefly Bemisia tabaci Gennadius (Hom., Aleyrodidae) on tomato plants
Authors: Kumar P. , Poehling H.‐M. , Borgemeister C.
Published: September 2006

Abstract:  Studies on three different neem treatment methods (seed, soil and foliar) and two different commercial neem products (NeemAzal T/S 1% azadirachtin and NeemAzalU 17% azadirachtin) against sweetpotato whitefly (WF) Bemisia tabaci Gennadius (Hom., Aleyrodidae) on tomato plants were conducted in cages in air‐conditioned cultivation rooms. All three methods of neem treatments resulted in reduced colonization and oviposition. Overall oviposition intensity was significantly reduced (44%) by the treatment of tomato seeds but an even higher reduction (74%) was achieved through soil drenching both with 3.0 g/l NeemAzalU and foliar spraying (82%) with 10 ml/l of NeemAzal TS compared with control treatments. In contrast, soil and foliar treatment increased fecundity per female up to 33% and 32%, respectively, at the highest tested concentrations. Reduced egg hatch could be observed only at high neem concentrations; 62% and 51% of deposited eggs hatched at the highest dose rates of NeemAzalU in case of seed and foliar treatments, respectively; whereas only 43% of deposited eggs hatched in case of foliar treatments at highest dose rates of NeemAzal T/S. Seed (35%), foliar (93%) and soil treatments (91%) caused high mortality rates of immatures and reduced number of hatching adults compared with control plants treated with a blank formulation or water. The mortality among immatures increased in relation to azadirachtin concentrations. Concerning susceptibility of different developmental stages, young larvae were the most sensitive. Foliar treatment was the most efficient, with 100% mortality for all three larval stages at high concentrations (10 ml/l of NeemAzal T/S) compared with 78–87% mortality with soil treatment (at 3.0 g/l NeemAzalU). The findings are discussed in the context of integrated control of WF in protected cultivation environments in the humid tropics.
Interaction of a solitary larval endoparasitoid, Microplitis mediator, with its host, Mamestra brassicae: host acceptance and host suitability
Authors: Lauro N. , Kuhlmann U. , Mason P. G. , Holliday N. J.
Published: September 2006

Abstract:  Microplitis mediator (Haliday) (Hym., Braconidae) is an important parasitoid of early instar larvae of the European cabbage moth, Mamestra brassicae L. (Lep., Noctuidae). In the laboratory, we examined attack responses of female M. mediator to the first three larval instars of M. brassicae. Females were presented with M. brassicae larvae either one individual at a time in a no‐choice experiment, or three individuals, one from each instar, simultaneously in a choice experiment. Whether or not there was choice, naïve female parasitoids attacked a high proportion of larvae and did not discriminate among instars. In the no‐choice experiment, attacked larvae were reared, and parasitoid cocoons were produced from about 76% of larvae attacked as first and second instars, but from only 19% of larvae attacked as third instars. Dissections of attacked larvae from the choice experiment showed that about 79% of attacks on first and second instars resulted in oviposition compared with only 49% for third instars. When given choice, frequency and number of attacks on first instar larvae increased with increasing parasitoid experience. Our results suggest that first and second instar larvae of M. brassicae are suitable hosts for M. mediator, but that third instar larvae are suboptimal both because oviposition attempts were frequently unsuccessful and because immature parasitoids failed to complete development. Nevertheless, naïve attacking parasitoids exhibited minimal discrimination among instars, although experienced parasitoids most frequently attacked first instar larvae. The host selection behaviour of M. mediator is discussed in the context of optimal foraging theory and implications for biological control.
Effect of body size and larval experience on mate preference in Helicoverpa armigera (Hübner) (Lep., Noctuidae)
Authors: Li Z. , Li D. , Xie B. , Ji R. , Cui J.
Published: September 2006

Abstract:  We studied the mating selection in the cotton bollworm, Helicoverpa armigera (Hübner), in relation to body size and larval diet in the laboratory. When provided with an artificial diet at larval stage, weight, body and forewing length did not affect the probability of a male/female moth being selected for mating, but the abdominal width of selected female moths was significantly wider than that of non‐selected female moths. 30 female moths were dissected and number of eggs was counted after mating, and there was a correlation between the abdominal width and egg number. There was also significant difference of weight loss between selected and non‐selected male/female moths after the mating. The effect of operational sex ratio on mating latency and copulation duration were tested, and the result indicated that mating latency of male selection was significantly longer than that of female selection, but the difference of copulation duration was not significant. Cotton, corn and peanut plants were provided to larvae to test the effect of larval host plant experience on mate choice. When cotton‐ and peanut‐fed moth severed as potential partners, both female and male of cotton‐fed moths significantly preferred cotton‐ to peanut‐fed moths for mating. The possible reasons for mate preference based on larval host plant experience may account for host plants attributes on sex pheromone variation and sexual maturity. These findings may impact Bacillus thuringiensis resistance management.
The pretarsus in Chalcidoidea (Hymenoptera Parasitica): functional morphology and possible phylogenetic implications
Authors: Gladun Dmytro , Gumovsky Alex
Published: September 2006

The structure of the pretarsus of chalcid wasps (Hymenoptera: Chalcidoidea) was examined with light and scanning electron microscopy. The pretarsus of these wasps is characterized by a distal elastic widening of the planta that spreads over the arcus, by a pair of folding plates at the dorsal side of the arolium (the dorsal plates), and by the absence of auxiliary sclerites. The surface of the fully spread arolium of chalcids has a spongiform structure. The arcus of chalcids is an apodeme of the planta. The peculiarities of the inverting/everting biomechanics of the pretarsus of chalcids involve: 1) interactions between the elastic part of the planta, the dorsal plates and the manubrium, and 2) the functioning of the elastic part of the planta and the arcus together as a single unit. A single apical seta situated distally from the campaniform sensillae and proximal row of setae on the manubrium are regarded as putative synapomorphies of Chalcidoidea. A manubrium with a distinct proximal row of three setae characterizes almost all Eulophidae, Aphelinidae and Signiphoridae (‘eulophid lineage’) and Tetracampidae, whereas a row of two setae characterizes Mymaridae, Rotoitidae and Trichogrammatidae. Other studied families (Pteromalidae, Eurytomidae, Torymidae, Ormyridae, Eupelmidae, Encyrtidae, Perilampidae), which represent a ‘pteromalid lineage’, are characterized mostly by five setae in a proximal row, which could represent a synapomorphy for these groups, or a symplesiomorphy in Chalcidoidea, depending on rooting. However, the characters may be correlated with differences in body size that characterize the different lineages rather than being phylogenetically important. Other characters that may be phylogenetically informative are: 1) shape of the manubrium (spindle‐like in Mymaridae, Rotoitidae, Trichogrammatidae and the ‘eulophid lineage’, but mostly bottle‐like in representatives of the ‘pteromalid lineage’), and 2) pubescence of the proximal part of the planta (sparse, thick setae in Rotoitidae, Trichogrammatidae and the ‘eulophid lineage’, but dense, slender setae in representatives of the ‘pteromalid lineage’).
REAL OPTIONS AND PATENT DAMAGES: THE LEGAL TREATMENT OF NON‐INFRINGING ALTERNATIVES, AND INCENTIVES TO INNOVATE
Authors: Hausman Jerry , Leonard Gregory K.
Published: August 2006

Abstract Patent litigation has become an increasingly important consideration in business strategy. Damage awards in patent litigation are supposed to compensate the patent owner for economic harm created by infringement and are therefore important for protecting returns to innovation. We analyze the effects that a recent court decision in the United States, called Grain Processing, has had on the incentives of potential infringers to infringe and innovators to innovate. We find that Grain Processing has decreased the expected value of damages awards in patent cases by conferring a ‘free option’ on infringers. Grain Processing also concluded that the patent owner in the case did not suffer lost profits due to the infringement because the infringer would have adopted an (inferior) non‐infringing technology had it not infringed. We demonstrate that this conclusion is inconsistent with standard economic models.
THE ROLE OF DIFFERENTIATION STRATEGY IN LOCAL TELECOMMUNICATION ENTRY AND MARKET EVOLUTION: 1999–2002*
Authors: GREENSTEIN SHANE , MAZZEO MICHAEL
Published: September 2006

We examine the role of differentiation among competitive local exchange carriers (CLECs) in nearly 1,200 U.S. cities in 1999 and 2002, before and after a valuation crash affecting communications firms. We test and reject the null hypothesis of homogeneous competitors. We also find strong evidence that differentiated CLECs account for both potential market demand and the business strategies of competitors when making their entry decisions. Finally, product heterogeneity in markets in 1999 helps predict how the structure of markets evolved through 2002. We conclude that the policy debate for local telecommunications regulation should account for differentiated behavior.
ENTRY DETERRENCE BY NON‐HORIZONTAL MERGER*
Authors: INNES ROBERT
Published: September 2006

We study when and how pure non‐horizontal mergers, whether cross‐product or vertical, can deter new entry. Organizational mergers implicitly commit firms to more aggressive price competition. Because heightened competition deters entry, mergers can occur in equilibrium even when, absent entry considerations, they do not. We show that, in order to prevent a flood of entrants, mergers arise even when a marginal merger costs incumbent firms more than does a marginal entrant.
Engineering resistance to geminiviruses – review and perspectives
Authors: Vanderschuren Hervé , Stupak Martin , Fütterer Johannes , Gruissem Wilhelm , Zhang Peng
Published: September 2006

Following the conceptual development of virus resistance strategies ranging from coat protein‐mediated interference of virus propagation to RNA‐mediated virus gene silencing, much progress has been achieved to protect plants against RNA and DNA virus infections. Geminiviruses are a major threat to world agriculture, and breeding resistant crops against these DNA viruses is one of the major challenges faced by plant virologists and biotechnologists. In this article, we review the most recent transgene‐based approaches that have been developed to achieve durable geminivirus resistance. Although most of the strategies have been tested in model plant systems, they are ready to be adopted for the protection of crop plants. Furthermore, a better understanding of geminivirus gene and protein functions, as well as the native immune system which protects plants against viruses, will allow us to develop novel tools to expand our current capacity to stabilize crop production in geminivirus epidemic zones.
Testing the Decline of Parliament Thesis: Ireland, 1923–2002
Authors: Elgie Robert , Stapleton John
Published: September 2006

There is a long-standing argument that in Westminster-style systems parliaments are in decline. The frequency with which the head of government intervenes in parliament is one indicator of this supposed decline. Studies conducted in Britain and Canada show that the frequency of prime ministerial interventions has declined over time, suggesting that the decline of parliament thesis holds true in this regard at least. This article examines the Irish case and shows that the situation is different. As in Britain and Canada, there has been a decline in particular forms of activity. However, the overall level has increased over time. These findings suggest that in the Irish case at least and on the basis of this one indicator the decline of parliament thesis does not hold true. Moreover, when we contextualise the findings, particularly on the basis of a qualitative analysis of the changing nature of the presentation of the Order of Business over the last 30 years, we find that the decline of parliament thesis is weakened further. Thus, this article suggests that the decline of parliament thesis is not applicable to all examples of Westminster-style parliamentary systems.
Integrated Deliberation: Reconciling Civil Society's Dual Role in Deliberative Democracy
Authors: Hendriks Carolyn M.
Published: September 2006

Among the growing literature on deliberative democracy there are two diverging streams of thought, each implying a different role for civil society. Micro deliberative theorists, with their focus on the procedural conditions for structured fora, encourage civil society to engage in collaborative practices, usually with the state. In contrast, macro deliberative democrats, who are interested in the messy and informal deliberation in the public sphere, advocate that civil society should work discursively outside and against the state. This article explores some of the implications of these conflicting roles, taking into account two observations from deliberative practice: first, that all micro deliberative fora are surrounded and impacted by their macro discursive context, and second, that some actors in civil society are more willing and capable of deliberating than others. To conceive of deliberative democracy as an entirely micro or macro enterprise is not only unrealistic, but potentially exclusive. The article advocates for a more viable and inclusive deliberative theory; one that integrates all kinds of deliberation from the micro to the macro. To this end, public deliberation is best conceptualised as an activity occurring in a range of discursive spheres that collectively engage a diversity of civil society actors.
Intra-Party Support for the Good Friday Agreement in the Ulster Unionist Party
Authors: Kaufmann Eric , Patterson Henry
Published: September 2006

Party organisations are often ‘black boxes' overlooked by scholars in favour of party leaders, manifestos and elections. Yet intra-party dynamics are often crucial. This article uses the example of the Ulster Unionist Party (UUP) to illustrate this. Events in the 1998–2003 period highlight the importance of splits within the party's governing Ulster Unionist Council (UUC) over the Good Friday Agreement (GFA) which underpins the Northern Ireland peace process. This article pioneers the use of postcode-profiling technology and uses multi-level analysis of a UUC party list to show that delegates' party section provides the best predictor of their stance towards the Good Friday Agreement. Consequently, the article argues that delegate voting behaviour within the UUC is best explained by reference to highly embedded, meso-level institutions which perpetuate networks and condition individual preferences.
Electoral Volatility and Party Decline in Western Democracies: 1970–1995
Authors: Drummond Andrew J.
Published: September 2006

In 1970, Richard Rose and Derek Urwin published a seminal piece on the stability of party support in Western democracies, ‘Persistence and Change in Western Party Systems Since 1945’. Everywhere they looked, established parties seemed to reflect stability rather than change, lending credence to the notion that party systems were ‘frozen’. Numerous subsequent studies, however, have produced mixed results. Part of what seems to be fueling this debate lies in the disparate measures researchers use to gauge stability. In this update of Rose and Urwin's study, I address the issue of comparable results by maintaining the same data source and methods they used to gauge the stability of party support, extending the study to the present. The results indicate that party system instability is on the rise throughout much of the West since 1970, with statistically significant increases seen in Scandinavia and across all regions combined. Furthermore, the parties which seem to be experiencing the most change are not only the newest parties – as the frozen cleavages thesis might predict – but also those parties formed during the interwar period, the large majority of which showed much greater stability in 1970.
Should the Voting Age be Lowered to Sixteen? Normative and Empirical Considerations
Authors: Chan Tak Wing , Clayton Matthew
Published: September 2006

This article is an examination of the issue of whether the age of electoral majority should be lowered to sixteen. We consider and reject several arguments raised by both sides of the voting age debate. The key issue, we claim, is the political maturity of young people. Drawing on empirical data collected in nationally representative surveys, we argue that the weight of such evidence suggests that young people are, to a significant degree, politically less mature than older people, and that the voting age should not be lowered to sixteen.
In Defence of Associative Political Obligations: Part One
Authors: Horton John
Published: September 2006

Part One of this article seeks to defend the idea of associative political obligations against a number of criticisms that have been advanced opposing it. The purpose of this defence is not to demonstrate that the associative account is therefore the best explanation of political obligations, but only that the principal reasons which have been given for rejecting it are much less compelling than its critics maintain. The argument focuses in particular on the various criticisms advanced by A. John Simmons. Two general lines of defence figure especially prominently. First, it is shown how many of the criticisms in one way or another ultimately rest on the assumption that political obligations must be voluntarily acquired, when it is just this assumption that is contested by an associative account. Secondly, it rebuts the charge that the idea of associative obligations faces a particular problem because it entails the view that members must have obligations to associations or groups that are evil. While it is not claimed that the idea of associative political obligations is entirely without difficulties, it is contended that stories of its demise are greatly exaggerated, and in this respect the ground is laid for Part Two of the article, which sketches a particular account of associative political obligations.
Reading in examination‐type situations: the effects of text layout on performance
Authors: Lonsdale Maria dos Santos , Dyson Mary C. , Reynolds Linda
Published: September 2006

Examinations are conventionally used to measure candidates' achievement in a limited time period. However, the influence of text layout on performance may compromise the construct validity of the examination. An experimental study looked at the effects of the text layout on the speed and accuracy of a reading task in an examination‐type situation. A survey of the reading strategies used in examinations was conducted to help in defining the reading context in which text layout may have an effect. A set of guidelines was also derived from research on typographic features of text and these were used to select three text layouts (intended to be more or less legible) from the layouts used in English language reading examinations. Results of the experiment showed that task time was significantly shorter and the number of correct answers per second was significantly higher with the layout conforming to legibility guidelines. Participants' judgements indicated that this layout was also the easiest in which to find answers and the most attractive. The main conclusion of the study is that text layout affects performance in a task that involves reading text to search for specific information in order to answer questions on it under time pressure. Consequently, the construct validity of examinations may be compromised by confounding legibility with reading skills.
CD4+/CD56+ haematodermic neoplasm: a preculsor haematological neoplasm that frequently first presents in the skin
Authors: Martín JM , Nicolau MJ , Galán A , Ferrández‐Izquierdo A , Ferrer AM , Jordá E
Published: August 2006

CD4+/CD56+ hematodermic neoplasm, formerly known as blastic NK cell lymphoma, is an aggressive and rare preculsor hematologic neoplasm recently recognized by the WHO‐EORTC classification consensus for cutaneous lymphomas. The neoplasm tends to affect elderly patients, who usually present with skin lesions but often have a disseminated disease, including bone marrow involvement. Although the lesions are composed of cells with a lymphoblast‐like morphology and an NK‐cell phenotype, exhibiting a CD4+, CD56+ positive immunophenotype, recent studies support a relationship to plasmacytoid dendritic cells. Because of the rarity of this disease, we describe two patients suffering a CD4+/CD56+ hematodermic neoplasm.
Accuracy of hepatitis C virus core antigen testing in pools among seroconverters
Authors: Beer Netta , Shinar Eilat , Novack Lena , Safi Jamal , Soliman Hassan , Yaari Arieh , Goldman‐Levi Ronit , Yahalom Vered , Bolotin Arkadi , Sarov Batia
Published: September 2006

BACKGROUND: Screening blood units for hepatitis C virus (HCV) with nucleic acid testing (NAT) reduces the risk associated with the long “window period” (8‐9 weeks) after HCV infection. The feasibility of adding the HCV core antigen assay in pools to the existing anti‐HCV individual screening was examined as an alternative of NAT, for early detection of HCV.

STUDY DESIGN AND METHODS: Eighteen HCV seroconversion panels were tested for HCV antibodies, HCV antigen, and HCV RNA. Each sample was tested for HCV antigen individually and in pools of 3, 6, and 12. Statistical analyses included estimation of time until detection of the first positive HCV antigen bleed in each pool size, with a locally weighted regression (LOWESS) model. Sensitivity was calculated compared to NAT.

RESULTS: Detection of HCV antigen in individual samples and in pools of 3 and 6 significantly preceded the detection of antibodies by 63, 53, and 46 days, respectively. Although the sensitivity of the HCV antigen test decreased with the increase in pool size, the estimated overall sensitivity of the “two‐stage” antigen and antibody screening (where NAT of individual samples was the gold standard) was not significantly different between individual and the different pool sizes.

CONCLUSION: Screening for HCV antigen in pools of 6 can be considered an efficient and easier‐to‐implement alternative to the costly NAT for identifying blood donors in the seroconversion period. It may offer a cost‐effective approach in resource utilization in poor countries, that, after the implementation of HCV antibody testing, want to further improve blood safety.
Viability of red cells prepared with S‐303 pathogen inactivation treatment
Authors: Rios Jorge A. , Hambleton Julie , Viele Maurene , Rugg Neeta , Sindermann Gail , Greenwalt Tibor , Wages David , Cook David , Corash Laurence
Published: September 2006

BACKGROUND: A nucleic acid–targeted pathogen inactivation process with S‐303 was developed to treat red blood cells (RBCs).

STUDY DESIGN AND METHODS: Three studies in healthy subjects investigated posttransfusion recovery, life span, and immunogenic potential of autologous RBCs treated with S‐303 and stored for 35 days. A two‐arm trial in 42 subjects (1A) examined recovery of 35‐day‐old S‐303 RBCs after a single transfusion. A one‐arm study (1B) measured recovery and immune response in 28 subjects after multiple transfusions of S‐303 RBCs. A randomized, crossover study (1C) in 29 subjects compared recovery and life span of 35‐day‐old S‐303 RBCs and conventional RBCs.

RESULTS: In Studies 1A and 1B, mean recovery of S‐303 RBCs ranged from 78.7 to 84.4 percent. In Phase 1C, the mean 24‐hour posttransfusion recoveries of S‐303 and untreated RBCs were 81.7 ± 6.3 and 84.5 ± 6.2 percent (p = 0.05). The median life spans (t1/2) of S‐303 and control RBCs were identical (37.4 days, p = 0.98). No antibodies to S‐303 RBCs were detected.

CONCLUSION: The mean 24‐hour recovery of 35‐day‐old S‐303 RBCs was less than untreated RBCs, but greater than 75 percent. RBCs treated with S‐303 and stored for 35 days exhibited median life span not different from that of conventional RBCs.
Quantification of hepatitis B virus genomes and infectivity in human serum samples
Authors: Hsia Chu Chieh , Purcell Robert H. , Farshid Mahmood , Lachenbruch Peter A. , Yu Mei‐ying W.
Published: September 2006

BACKGROUND: Hepatitis B virus (HBV) infections are still a major health issue, with approximately 350 million people chronically infected with HBV worldwide. Information about the minimum copy number of HBV genomes required for infection would be useful as a reference for drug and vaccine development; for monitoring HBV patients during treatment; for screening of blood, organ, and tissue donors; and for regulating nucleic acid amplification assays for HBV.

STUDY DESIGN AND METHODS: Serum samples from chronic carriers (hepatitis B surface antigen–positive and antibody to HBV core antigen–positive) of the three most common subtypes of HBV were studied; their infectivity titers had been evaluated previously in chimpanzees. The genotypes of the HBV samples were determined by DNA sequences and type‐specific amino acids of the S gene of HBV. Copy numbers of HBV DNA were quantified by real‐time TaqMan polymerase chain reaction (PCR) and by nested PCR applied to limiting dilutions. The copy number determined for each inoculum was compared with previously defined chimpanzee infectivity titers.

RESULTS: The genotypes of the HBV adw, ayw, and adr inocula were A, D, and C, respectively. The concentration of HBV DNA was determined to be 5.4 × 109, 2.5 × 109, and 3.1 × 108 genome equivalents (geq) per mL for serum samples containing the adw, ayw, and adr, respectively. The chimpanzee infectivity titers per milliliter of these initial HBV‐containing serum samples were previously determined to be 107.5 for adw, 107.5 for ayw (MS‐2 strain), and 108 for adr.

CONCLUSION: The minimal copy number of HBV DNA in chronic carriers of HBV that can infect the chimpanzee model was estimated to be from 3 to 169 geq based upon the three well‐characterized inocula.
Evaluation of inactivation methods for severe acute respiratory syndrome coronavirus in noncellular blood products
Authors: Darnell Miriam E.R. , Taylor Deborah R.
Published: September 2006

BACKGROUND: Severe acute respiratory syndrome coronavirus (SARS‐CoV) has been detected in the blood of infected individuals, which may have the potential to contaminate donated blood and plasma‐derived products in the event of a future outbreak. Effective methods for inactivating the SARS‐CoV in protein solutions are described in this report.

STUDY DESIGN AND METHODS: Heat, ultraviolet (UV) irradiation, octanoic acid, and solvent/detergent (S/D) methods were tested individually for their ability to inactivate SARS‐CoV in protein solutions appropriately mimicking blood‐derived products. Treated samples were tested for inactivation in a tissue culture growth assay.

RESULTS: Viral inactivation by heat treatment at 60°C required 15 to 30 minutes to inactivate the SARS‐CoV. UVC efficiently inactivated SARS‐CoV in 40 minutes, whereas UVA required the addition of psoralen to enhance inactivation of the virus. The presence of bovine serum albumin limited the ability of UVC and UVA to inactivate SARS‐CoV and octanoic acid treatment does not reduce the infectivity of SARS‐CoV–spiked protein solutions. S/D treatment required 2, 4, and up to 24 hours for Triton X‐100, Tween 80, and sodium cholate inactivation, respectively.

CONCLUSION: Heat, UVC irradiation, and S/D treatments effectively inactivate SARS‐CoV, whereas octanoic acid treatment is insufficient for inactivation of the virus.
Two‐year experience with aerobic culturing of apheresis and whole blood–derived platelets
Authors: Kleinman Steven H. , Kamel Hany T. , Harpool Dennis R. , Vanderpool Sandra K. , Custer Brian , Wiltbank Thomas B. , Nguyen Kim‐Anh , Tomasulo Peter A.
Published: September 2006

BACKGROUND: Throughout its system of regional centers, Blood Systems implemented culture based bacterial testing with a standardized protocol for both apheresis and whole blood–derived platelets (PLTs).

STUDY DESIGN AND METHODS: After a 24‐hour hold, 4 mL of PLT product was inoculated into an aerobic bottle (BacT/ALERT, bioMérieux). Cultures were incubated for 24 hours before routine product release to prevent distribution of infected products while minimizing consignee notification, product retrievals, and hospital PLT inventory problems. Initial‐positives were further tested (and bacteria identified) by performing cultures from the original component and subcultures from the BacT/ALERT bottle. Results were categorized according to AABB recommended definitions with minor modifications.

RESULTS: The rate of true‐positive detections from culturing 122,971 apheresis PLTs was 0.017 percent (95% confidence interval [CI], 0.011%‐0.026%). All true‐positive microorganisms were Gram‐positive with a predominance of coagulase‐negative Staphylococcus and Bacillus species. Twenty of the 21 true‐positive samples (95%) were detected by 24 hours but only 14 (68%) were detected by 18 hours. The false‐positive rate due to contamination was 0.1 percent with the majority of isolates being skin or environmental organisms. Results did not differ significantly for whole blood–derived versus apheresis PLTs.

CONCLUSION: These data corroborate the fact that the rate of detection of truly contaminated PLT apheresis products in the United States is approximately 1 in 5000 (0.02%); this is lower than the 0.03 to 0.05 percent rates that were generally quoted in the literature before the implementation of prospective bacterial culturing programs.
Within‐Animal Variation as an Indication of the Minimal Magnitude of the Critical Effect Size for Continuous Toxicological Parameters Applicable in the Benchmark Dose Approach
Authors: Dekkers Susan , Telman Jan , Rennen Monique A. J. , Appel Marco J. , De Heer Cees
Published: September 2006

In this study, the within‐animal variation in routinely studied continuous toxicological parameters was estimated from temporal fluctuations in individual healthy nonexposed animals. Assuming that these fluctuations are nonadverse, this within‐animal variation may be indicative of the minimal magnitude of the critical effect size (CES). The CES is defined as the breaking point between adverse and nonadverse changes in a continuous toxicological parameter, at the level of the individual organism. The total variation in the data from individual nonexposed animals was divided in variation parts due to known factors (differences in sex, animal, and day) and a residual variation, by means of analysis of variance. Using the residual variation and the estimated analytical measurement error of a toxicological parameter, the within‐animal variation can be estimated. The data showed within‐animal variations ranging between 0.6% and 34% for different clinical chemistry and hematological parameters in 90‐day rat studies. This indicates that different (minimal) CES values may be applicable for different parameters.
Estimating Preventable Fractions of Disease Caused by a Specified Biological Mechanism: PAHs in Smoking Lung Cancers as an Example
Authors: Cox Louis Anthony (Tony) , Sanders Edward
Published: September 2006

Epidemiology textbooks often interpret population attributable fractions based on 2 × 2 tables or logistic regression models of exposure‐response associations as preventable fractions, i.e., as fractions of illnesses in a population that would be prevented if exposure were removed. In general, this causal interpretation is not correct, since statistical association need not indicate causation; moreover, it does not identify how much risk would be prevented by removing specific constituents of complex exposures. This article introduces and illustrates an approach to calculating useful bounds on preventable fractions, having valid causal interpretations, from the types of partial but useful molecular epidemiological and biological information often available in practice. The method applies probabilistic risk assessment concepts from systems reliability analysis, together with bounding constraints for the relationship between event probabilities and causation (such as that the probability that exposure X causes response Y cannot exceed the probability that exposure X precedes response Y, or the probability that both X and Y occur) to bound the contribution to causation from specific causal pathways. We illustrate the approach by estimating an upper bound on the contribution to lung cancer risk made by a specific, much‐discussed causal pathway that links smoking to a polycyclic aromatic hydrocarbon (PAH) (specifically, benzo(a)pyrene diol epoxide–DNA) adducts at hot spot codons at p53 in lung cells. The result is a surprisingly small preventable fraction (of perhaps 7% or less) for this pathway, suggesting that it will be important to consider other mechanisms and non‐PAH constituents of tobacco smoke in designing less risky tobacco‐based products.
A Macro‐Economic Framework for Evaluation of Cyber Security Risks Related to Protection of Intellectual Property
Authors: Andrijcic Eva , Horowitz Barry
Published: September 2006

The article is based on the premise that, from a macro‐economic viewpoint, cyber attacks with long‐lasting effects are the most economically significant, and as a result require more attention than attacks with short‐lasting effects that have historically been more represented in literature. In particular, the article deals with evaluation of cyber security risks related to one type of attack with long‐lasting effects, namely, theft of intellectual property (IP) by foreign perpetrators. An International Consequence Analysis Framework is presented to determine (1) the potential macro‐economic consequences of cyber attacks that result in stolen IP from companies in the United States, and (2) the likely sources of such attacks. The framework presented focuses on IP theft that enables foreign companies to make economic gains that would have otherwise benefited the U.S. economy. Initial results are presented.