bluuebunny/crossref_metadata_2025 huggingface dataset:
Constitutions As Expressive Documents
Authors: Brennan Geoffrey , Hamlin Alan
Published: September 2009

This article looks at constitutions as expressive documents. Two concepts are the main focus of this article: the constitution and the notion of expressiveness. The article tries to clarify these concepts by appeal of a contrast, which will be between a constitution as a legal document and the more general idea of a constitution, which is envisaged by the Constitutional Political Economy (CPE). It also tries to clarify the notion of expressive activity, followed by a discussion on the issue of how expressiveness operates in electoral politics. Finally, a simple two-by-two matrix is used to explore the role of expressive elements in constitutions.
The Role of the State in Development
Authors: Bates Robert H.
Published: September 2009

This article studies the role of the state in development. It provides a review of the relevant literature and gives a distinctive argument that highlights areas suitable for empirical investigation. One of these areas is the politics that descend into predation, while the others turn developmental. It determines the conditions under which the provision of security and the creation of wealth become rational political acts. The article also discusses stateless societies, societies with states, state failure, and the development of the state.
Old Questions and New Answers about Institutions: The Riker Objection Revisited
Authors: Shepsle Kenneth A.
Published: September 2009

This article revisits some old issues about institutions and suggests some new considerations. The article is focused on micro-analytical aspects of institutions and on interpretations of institutions that are micro-analytical, and that explicitly involve human agency, and are game theoretic. It then determines how institutions are chosen and maintained, before moving on to a discussion of the Riker Objection and modes of procedural change.
The ICT paradigm
Authors: Freeman Chris
Published: September 2009

By the end of the twentieth century it was already clearly evident that the new leading ICT industries were firmly established as the leading sectors of the economy in the United States. Indeed, although they still accounted for a relatively small proportion of aggregate production and employment, their rate of growth was so high that they accounted for over half of total growth in the US economy in the 1990s, and gave rise to a huge financial bubble early in the next century. This article deals with the origins and definition of the paradigm concept; with the formation and collapse of the Bubble; and finally with a critique of some myths that have attended diffusion of The ICT Paradigm which were (and to some extent still are) the intellectual counterpart of the financial bubble.
Surveillance, power, and everyday life
Authors: Lyon David
Published: September 2009

Surveillance grows constantly, especially in the countries of the global north. Although as a set of practices it is as old as history itself, systematic surveillance became a routine and inescapable part of everyday life in modern times and is now, more often than not, dependent on information and communication technologies (ICTs). Indeed, it now makes some sense to talk of ‘surveillance societies’, so pervasive is organizational monitoring of many kinds. Fast developing technologies combined with new governmental and commercial strategies mean that new modes of surveillance proliferate, making surveillance expansion hard to follow, let alone analyse or regulate.
Intention‐Based Semantics
Authors: Borg Emma
Published: September 2009

There is a sense in which it is trivial to say that one accepts intention- (or convention-)based semantics. For if what is meant by this claim is simply that there is an important respect in which words and sentences have meaning (either at all or the particular meanings that they have in any given natural language) due to the fact that they are used, in the way they are, by intentional agents (i.e. speakers), then it seems no one should disagree. For imagine a possible world where there are physical things which share the shape and form of words of English or Japanese, or the acoustic properties of sentences of Finnish or Arapaho, yet where there are no intentional agents (or where any remaining intentional agents don't use language). In such a world, it seems clear that these physical objects, which are only superficially language-like, will lack all meaning.
Relevance Theory—New Directions and Developments
Authors: Carston Robyn , Powell George
Published: September 2009

Much work in relevance theory relies on the kinds of method and data familiar to linguistic philosophers: essentially introspection and native speaker intuitions on properties such as truth conditions, truth values, what is said, etc. Recently, however, relevance theorists have been at the forefront of a newly-emerging research field, experimental pragmatics, which aims to apply the empirical techniques of psycholinguistics to questions about utterance interpretation. Over the last few years, this new research methodology has thrown up interesting and sometimes surprising insights into the psychological processes underlying human communication and comprehension, some of which are discussed in this article.
What I Know When I Know a Language
Authors: Smith Barry C.
Published: September 2009

Every speaker of a language knows a bewildering variety of linguistic facts, and will come to know many more. It is nowledge that connects sound and meaning. Questions about the nature of this knowledge cannot be separated from fundamental questions about the nature of language. The conception of language we should adopt depends on the part it plays in explaining our knowledge of language. This article explores options in accounting for language, and our knowledge of language, and defends the view that individuals' languages are constituted by the standing knowledge they carry from one speech situation to another.
Introduction
Authors: Steinbock Bonnie
Published: September 2009

This article includes a short history of bioethics and the major issues surrounding bioethics. At its inception, the central issues in bioethics were research with human subjects, genetics, organ transplantation, death and dying, and reproduction. These continue to be important issues today. Methodology has been a central theoretical issue since the very beginning of bioethics. While some hoped that bioethics would generate a single correct normative theory, that idea has been given up by most practitioners. Indeed, bioethics reflects a wide range of theoretical approaches in normative ethics, including utilitarianism, deontology, natural law, contractarianism, virtue ethics, communitarianism, pragmatism, and feminist ethics.
Organ Transplantation
Authors: Munson Ronald
Published: September 2009

The ethical and social issues raised by transplants are so interrelated that the thread of any problem eventually leads to the whole tangled ball. This article, however, limits discussion to topics involving living donors in the United States. This restriction is not dictated solely by space constraints. Rather, the rise in the number of living donors gives a particular urgency to questions about informed consent, donor protection, and recipient needs. How we resolve conflicts of interest, address issues of consent, and define the scope of autonomy will shape the policies and practices that determine whether donors are protected and whether lives are lost or saved.
Biobanking
Authors: Irving Louise , Harris John
Published: September 2009

This article looks at some of the chance discoveries and elegant ideas that were borne out through the availability of archived tissue samples. It then discusses some of the planned changes to the method and purpose of tissue storage and collection. The changes are in the form of new types of tissue bank, or biobank as they are conceived. These banks are part of a trend to move towards a preventative approach to public health rather than the current costly interventionist model. This approach is not without its problems and it is these that threaten the unfettered continuation of the tissue archive. The sophistication of new research tools can uncover information about individuals that may have a detrimental effect on their well-being in various ways. The article analyses these possibilities in the context of how health care might develop.
Precedent Autonomy, Advance Directives, and End‐of‐Life Care
Authors: Davis John K.
Published: September 2009

Bioethicists are widely agreed that patients have a right of self-determination over how they are treated. Our duty to respect this is said to be based on the principle of respect for autonomy. In end-of-life care the patient may be incompetent and unable to exercise that right. One solution is to exercise it in advance. Advance directives, which include living wills and powers of attorney for health care, enable people to decide (or least influence) what medical treatment they will receive later, when they become incompetent. Advance directives have been criticized in two general ways. First, many critics contend that advance directives fail on a practical level to effect a patient's autonomous choices because, for example, people cannot foresee their futures well enough to make informed decisions in advance. Second, many critics contend that, practical problems aside, there is no moral authority for exercising control over one's incompetent future self.
Moral Status, Moral Value, and Human Embryos: Implications for Stem Cell Research
Authors: Steinbock Bonnie
Published: September 2009

This article begins with an introduction to the biology behind embryonic stem cell (ESC) research. Next it presents briefly four views of moral status, based on four different criteria: biological humanity, personhood, possession of interests, and having a future-like-ours (FLO). On two of these views (the person view and the interest view), embryos clearly lack moral status, but they most likely do not have moral status on the FLO account either. Only the biological humanity criterion combined with the view that life begins at conception results in the conclusion that very early extracorporeal embryos have full moral status, making ESC research that destroys embryos morally wrong. This explains why even some who are anti-abortion are not against ESC research: they do not view the very early, extracorporeal embryo as having the same moral status as the fetus.
Therapeutic Cloning: Politics and Policy
Authors: Bonnicksen Andrea
Published: September 2009

Much of the literature on therapeutic somatic cell nuclear transfer (SCNT) covers the moral arguments for and against proceeding and the policy stall occasioned by conflicts over the moral status of embryos. Yet it is also worthwhile to view policy from the standpoint of the resources available as well as of deficiencies in those resources. This article uses the idea of a policy community to examine policy making from a starting point that focuses not on what divides, but rather on the groups and individuals committed to enabling ES cell research and therapeutic SCNT. Although written with international dimensions in mind, the article focuses on the United States, where the politics are particularly volatile and the likelihood of policy leadership at the national level is remote.
War, Trade, and State Formation
Authors: Spruyt Hendrik
Published: September 2009

This article provides a short account of European state formation. The generative factors behind the transformation of late medieval forms of government to new types of authority are discussed in the first section. This transformation was conducted through the selection and convergence among these distinct types of authority. The article moves on to a discussion of the process of state formation and its effects on the type of regime that emerged in different states. It determines how state formation implicated the rise of constitutionalist or absolutist forms of rule and highlights how the accounts of state formation in Europe currently inform the study of state development in newly emerging countries. Finally, the article identifies rather intriguing topics for further enquiry.
National Identity
Authors: Greenfeld Liah , Eastwood Jonathan
Published: September 2009

This article looks at the study of national identity, which must start with a preliminary investigation of the question of identity. It provides definitions of national identity and nationalism before moving on to historical explanations for the rise of nationalism. It also identifies types of nationalism and their political implications.
Ethnicity and Ethnic Conflict
Authors: Varshney Ashutosh
Published: September 2009

This article focuses on ethnic conflict and ethnic identity. It begins by differentiating these from nationalism, national identity, and civil wars. It presents a survey of the explanations provided in four traditions of enquiry, and also provides an analysis of the inadequacies or merits of arguments within each tradition. The article also reviews the evolution of arguments related to this field.
What Causes Democratization?
Authors: Geddes Barbara
Published: September 2009

This article tries to determine what causes democratization. It begins by studying the cause of the correlation between development and democracy, and views the models of democratization as strategic interactions between elites and citizens. The last section considers two context differences that might influence the democratization process: the historical period it takes place in and the type of regime that democracy replaces.
Regulation of the type IV pili molecular machine by dynamic localization of two motor proteins
Authors: Bulyha Iryna , Schmidt Carmen , Lenz Peter , Jakovljevic Vladimir , Höne Andrea , Maier Berenike , Hoppert Michael , Søgaard‐Andersen Lotte
Published: September 2009

Type IV pili (T4P) are surface structures that undergo extension/retraction oscillations to generate cell motility. In Myxococcus xanthus, T4P are unipolarly localized and undergo pole‐to‐pole oscillations synchronously with cellular reversals. We investigated the mechanisms underlying these oscillations. We show that several T4P proteins localize symmetrically in clusters at both cell poles between reversals, and these clusters remain stationary during reversals. Conversely, the PilB and PilT motor ATPases that energize extension and retraction, respectively, localize to opposite poles with PilB predominantly at the piliated and PilT predominantly at the non‐piliated pole, and these proteins oscillate between the poles during reversals. Therefore, T4P pole‐to‐pole oscillations involve the disassembly of T4P machinery at one pole and reassembly of this machinery at the opposite pole. Fluorescence recovery after photobleaching experiments showed rapid turnover of YFP–PilT in the polar clusters between reversals. Moreover, PilT displays bursts of accumulation at the piliated pole between reversals. These observations suggest that the spatial separation of PilB and PilT in combination with the noisy PilT accumulation at the piliated pole allow the temporal separation of extension and retraction. This is the first demonstration that the function of a molecular machine depends on disassembly and reassembly of its individual parts.
A low carbohydrate Mediterranean diet improves cardiovascular risk factors and diabetes control among overweight patients with type 2 diabetes mellitus: a 1‐year prospective randomized intervention study
Authors: Elhayany A. , Lustman A. , Abel R. , Attal‐Singer J. , Vinker S.
Published: September 2009

Background: The appropriate dietary intervention for overweight persons with type 2 diabetes mellitus (DM2) is unclear. Trials comparing the effectiveness of diets are frequently limited by short follow‐up times and high dropout rates.

Aim: The effects of a low carbohydrate Mediterranean (LCM), a traditional Mediterranean (TM), and the 2003 American Diabetic Association (ADA) diet were compared, on health parameters during a 12‐month period.

Methods: In this 12‐month trial, 259 overweight diabetic patients (mean age 55 years, mean body mass index 31.4 kg/m2) were randomly assigned to one of the three diets. The primary end‐points were reduction of fasting plasma glucose, HbA1c and triglyceride (TG) levels.

Results: 194 patients out of 259 (74.9%) completed follow‐up. After 12 months, the mean weight loss for all patients was 8.3 kg: 7.7 kg for ADA, 7.4 kg for TM and 10.1 kg for LCM diets. The reduction in HbA1c was significantly greater in the LCM diet than in the ADA diet (−2.0 and −1.6%, respectively, p < 0.022). HDL cholesterol increased (0.1 mmol/l ± 0.02) only on the LCM (p < 0.002). The reduction in serum TG was greater in the LCM (−1.3 mmol/l) and TM (−1.5 mmol/l) than in the ADA (−0.7 mmol/l), p = 0.001.

Conclusions: An intensive 12‐month dietary intervention in a community‐based setting was effective in improving most modifiable cardiovascular risk factors in all the dietary groups. Only the LCM improved HDL levels and was superior to both the ADA and TM in improving glycaemic control.
Exenatide compared with long‐acting insulin to achieve glycaemic control with minimal weight gain in patients with type 2 diabetes: results of the Helping Evaluate Exenatide in patients with diabetes compared with Long‐Acting insulin (HEELA) study
Authors: Davies M. J. , Donnelly R. , Barnett A. H. , Jones S. , Nicolay C. , Kilcoyne A.
Published: September 2009

Aim: The Helping Evaluate Exenatide in overweight patients with diabetes compared with Long‐Acting insulin (HEELA) study was designed to examine whether the glucagon‐like peptide‐1 (GLP‐1) receptor agonist, exenatide, could improve HbA1c (≤7.4%) with minimal weight gain (≤1 kg) compared with insulin glargine.

Methods: Patients [body mass index (BMI) >27 kg/m2] with elevated cardiovascular risk and type 2 diabetes inadequately controlled on two or three oral antidiabetes drugs (OADs) were randomized to add‐on exenatide 5–10 μg b.i.d. (n = 118) or insulin glargine o.d. (titrated to target fasting plasma glucose ≤5.6 mmol/l; n = 117) for 26 weeks.

Results: The study population had baseline mean (s.d.) age of 56.5 (9.1) years and BMI of 34.1 (5.3) kg/m2, and 58.5% of patients were taking two OADs. Mean baseline HbA1c was 8.65 (0.68)% in the exenatide group and 8.48 (0.66)% in the insulin glargine group. The proportions of patients achieving the composite endpoint of HbA1c ≤7.4% with weight gain ≤1 kg were 53.4% for the exenatide group and 19.8% for the insulin glargine group (p < 0.001 for exenatide vs. insulin glargine). Exenatide and insulin glargine did not demonstrate a significant difference in HbA1c improvements [least square (LS) mean [s.e.m.]: −1.25 [0.09]% and −1.26 [0.09]% respectively; p = 0.924], but had divergent effects on body weight (−2.73 [0.31] vs. +2.98 [0.31] kg respectively, p < 0.001) after 26 weeks. There were more treatment‐related adverse events with exenatide but a lower incidence of nocturnal hypoglycaemia, with no differences in overall or severe hypoglycaemia.

Conclusions: Additional treatment with exenatide resulted in significantly more overweight and obese patients with an elevated cardiovascular risk and type 2 diabetes achieving better glycaemic control with minimal weight gain compared with insulin glargine.
Firm Experience and Market Entry by Venture Capital Firms (1962–2004)
Authors: Dimov Dimo , Martin de Holan Pablo
Published: September 2009

abstract

In this paper, we examine a firm's decision to enter new markets as related to the depth and breadth of its experience and the relative distance of those markets. We situate our discussion and analysis in the context of the venture capital (VC) industry, and examine whether and when US VC firms enter five high‐technology investment markets through first‐ or later‐round investments. This setting allows us to observe both the firms that chose to enter a new market and those that did not, and analyse the antecedents of these decisions. We find that VC firms overall are less likely to enter distant markets; those with broader experience are more likely to make first‐round entries. In addition, VC firms with deeper investment experience are more likely to make first‐round entries in proximate markets and less likely to enter distant markets and make later‐round entries. These results offer interesting implications for the literature on organizational learning and entrepreneurship.
Finite Size Effect on the Sinterability and Dielectric Properties of ZnNb2O6–ZBS Glass Composites
Authors: Sanoj Mukkuttiparambil Ayyappan , Reshmi Chalappurath Pattelath , Varma Manoj Raama
Published: September 2009

ZnNb2O6 (ZN) is a columbite‐structured niobate compound showing excellent dielectric properties and comparatively low sintering temperatures (∼1200°C). Hence it is a good candidate for possible low‐temperature cofired ceramics (LTCC) applications. In the present investigation, ZnNb2O6 was synthesized in the form of micrometer‐sized powder using a conventional solid‐state ceramic synthesis route as well as in the form of nanosized powder by a polymer complex method. The finite size effect of ZN particles on sinterability and microwave dielectric properties of sintered pellets was evaluated. The phase formation was confirmed from the X‐ray diffraction (XRD) analysis. The particle size distribution of the nanoparticles was found to be of the order of 18–20 nm by using high‐resolution transmission electron microscopy analysis and 30 nm by analyzing the XRD patterns using Debye Scherrer's formula, after correcting for the instrument broadening effects. A ZN–60ZnO–30B2O3–10SiO2 (ZBS) composite was made by adding predetermined amounts of glasses. The microstructures of the sintered pellets of ZN and ZN–ZBS composites were examined using scanning electron microscopy and analyzed using image analysis. The nano‐ZN–ZBS composites were sintered to 93% of the reported density at 925°C/2 h, with microwave dielectric properties of ɛr=22.5, Q×f∼12 800 GHz, and τf=−69.6 ppm/°C, emerging as a potential material for possible LTCC applications.
Influence of Grain Size on Impedance Spectra and Resistance Degradation Behavior in Acceptor (Mg)‐Doped BaTiO3Ceramics
Authors: Yoon Seok‐Hyun , Randall Clive A. , Hur Kang‐Heon
Published: September 2009

The effect of acceptor concentration in (Mg)‐doped BaTiO3on the resistance degradation behavior was contrasted between coarse‐ and fine‐grain samples with ∼90 and ∼0.8 μm in size, respectively. Both cases showed similar trends that the time to degradation decreased systematically with the increase of acceptor concentration, however the absolute rates are very different for a given dopant concentration. Although the grain size and grain boundaries are important, it is also shown through an impedance analysis that the degradation behavior depends on the grain conductivity (σg) and ionic transference number (tion) as evaluated by the Warburg impedance. Under the condition of the same nominal acceptor concentration, fine‐grain samples showed much lower grain conductivity (σg) but little differences in the grain boundary conductivity (σgb) than that of coarse‐grain samples. The ionic transference number (tion) was also much smaller in fine‐grain samples. These results show that the actual effective acceptor concentration on being ionically compensated to enhance oxygen vacancies becomes smaller with the decrease of grain size. This fact coupled to the increase of the number of grain boundaries accounts for the improved degradation behavior with the decrease of grain size.
Raising demand and the future of progressive politics
Authors: Lent Adam
Published: September 2009

The economic crash has seen demand collapse. It can only be rebuilt by a radical transformation of British business practices and greater income equality, says Adam Lent
Liberalism in the Twilight Zone
Authors: Freeden Michael
Published: September 2009

One of Britain's leading experts on liberalism, Michael Freeden, critiques The Liberal Republic by Richard Reeves and Philip Collins1
Reforming the social housing waiting game
Authors: Turner Ed
Published: September 2009

The UK's social housing stock is a precious resource that needs to be allocated as fairly and transparently as possible but under current arrangements it is families who try to find themselves alternative accommodation that often get penalised. Reform is needed, says Ed Turner
Navigating the migration debate out of a dangerous cul‐de‐sac
Authors: Finch Tim , Mulley Sarah
Published: September 2009

Progressives cannot continue to bang the pro‐migration drum and believe that the public will finally ‘get it’ or that their arguments will win over the extreme anti‐migration voices. Instead a new mainstream consensus on the issue is urgently needed, say Tim Finch and Sarah Mulley
Magnetic Resonance Imaging in Dogs with Neurologic Impairment Due to Acute Thoracic and Lumbar Intervertebral Disk Herniation
Authors: Levine J.M. , Fosgate G.T. , Chen A.V. , Rushing R. , Nghiem P.P. , Platt S.R. , Bagley R.S. , Kent M. , Hicks D.G. , Young B.D. , Schatzberg S.J.
Published: September 2009

Background: Magnetic resonance imaging (MRI) is a correlate to physical examination in various myelopathies and a predictor of functional outcome.

Objectives: To describe associations among MRI features, neurological dysfunction before MRI, and functional outcome in dogs with disk herniation.

Animals: One hundred and fifty‐nine dogs with acute thoracolumbar disk herniation.

Methods: Retrospective case series. Signalment, initial neurological function as assessed by a modified Frankel score (MFS), and ambulatory outcome at hospital discharge and >3 months (long‐term) follow‐up were recorded from medical records and telephone interview of owners. Associations were estimated between these parameters and MRI signal and morphometric data.

Results: Dogs with intramedullary T2W hyperintensity had more severe pre‐MRI MFS (median 2, range 0–4) and lower ambulatory proportion at long‐term follow‐up (0.76) than those dogs lacking hyperintensity (median MFS 3, range 0–5; ambulatory proportion, 0.93) (P=.001 and .013, respectively). Each unit of T2W length ratio was associated with a 1.9 times lower odds of long‐term ambulation when adjusted for pre‐MRI MFS (95% confidence interval 1.0–3.52, P=.05). Dogs with a compressive length ratio >1.31 (which was the median ratio within this population) had more severe pre‐MRI MFS (median 3, range 0–5) compared with those with ratios ≤1.31 (median MFS 3, range 0–4; P=.006).

Conclusions and Clinical Importance: MRI features were associated with initial injury severity in dogs with thoracolumbar disk herniation. Based on results of this study, the T2W length ratio and presence of T2W intramedullary hyperintensity appear to be predictive of long‐term ambulatory status.
Characterization of a New Metallo-β-Lactamase Gene,
bla
NDM-1
, and a Novel Erythromycin Esterase Gene Carried on a Unique Genetic Structure in
Klebsiella pneumoniae
Sequence Type 14 from India
Authors: Yong Dongeun , Toleman Mark A. , Giske Christian G. , Cho Hyun S. , Sundman Kristina , Lee Kyungwon , Walsh Timothy R.
Published: September 2009

A Swedish patient of Indian origin traveled to New Delhi, India, and acquired a urinary tract infection caused by a carbapenem-resistant
Klebsiella pneumoniae
strain that typed to the sequence type 14 complex. The isolate,
Klebsiella pneumoniae
05-506, was shown to possess a metallo-β-lactamase (MBL) but was negative for previously known MBL genes. Gene libraries and amplification of class 1 integrons revealed three resistance-conferring regions; the first contained
bla
CMY-4
flanked by IS
EcP1
and
blc
. The second region of 4.8 kb contained a complex class 1 integron with the gene cassettes
arr
-
2
, a new erythromycin esterase gene;
ereC
;
aadA1
; and
cmlA7
. An intact IS
CR1
element was shown to be downstream from the
qac
/
sul
genes. The third region consisted of a new MBL gene, designated
bla
NDM-1
, flanked on one side by
K. pneumoniae
DNA and a truncated IS
26
element on its other side. The last two regions lie adjacent to one another, and all three regions are found on a 180-kb region that is easily transferable to recipient strains and that confers resistance to all antibiotics except fluoroquinolones and colistin. NDM-1 shares very little identity with other MBLs, with the most similar MBLs being VIM-1/VIM-2, with which it has only 32.4% identity. As well as possessing unique residues near the active site, NDM-1 also has an additional insert between positions 162 and 166 not present in other MBLs. NDM-1 has a molecular mass of 28 kDa, is monomeric, and can hydrolyze all β-lactams except aztreonam. Compared to VIM-2, NDM-1 displays tighter binding to most cephalosporins, in particular, cefuroxime, cefotaxime, and cephalothin (cefalotin), and also to the penicillins. NDM-1 does not bind to the carbapenems as tightly as IMP-1 or VIM-2 and turns over the carbapenems at a rate similar to that of VIM-2. In addition to
K. pneumoniae
05-506,
bla
NDM-1
was found on a 140-kb plasmid in an
Escherichia coli
strain isolated from the patient's feces, inferring the possibility of in vivo conjugation. The broad resistance carried on these plasmids is a further worrying development for India, which already has high levels of antibiotic resistance.
Superior Protective Immunity against Murine Listeriosis by Combined Vaccination with CpG DNA and RecombinantSalmonella entericaSerovar Typhimurium
Authors: Berchtold Christina , Panthel Klaus , Jellbauer Stefan , Köhn Brigitte , Roider Elisabeth , Partilla Miriam , Heesemann Jürgen , Endres Stefan , Bourquin Carole , Rüssmann Holger
Published: September 2009

Preexisting antivector immunity can severely compromise the ability ofSalmonella entericaserovar Typhimurium live vaccines to induce protective CD8 T-cell frequencies after type III secretion system-mediated heterologous protein translocation in orally immunized mice. To circumvent this problem, we injected CpG DNA admixed to the immunodominant p60217-225peptide fromListeria monocytogenessubcutaneously into BALB/c mice and coadministered a p60-translocatingSalmonellastrain by the orogastric route. The distribution of tetramer-positive p60217-225-specific effector and memory CD8 T cells was analyzed by costaining of lymphocytes with CD62L and CD127. In contrast to the single oral application of recombinantSalmonellaor single immunization with CpG and p60, in the spleens from mice immunized with a combination of both vaccine types a significantly higher level of p60-specific CD8 T cells with a predominance of the effector memory T-cell subset was detected. In vivo protection studies revealed that this CD8 T-cell population conferred sterile protective immunity against a lethal infection withL. monocytogenes. However, p60-specific central memory CD8 T cells induced by single vaccination with CpG and p60 were not able confer effective protection against rapidly replicating intracellularListeria. In conclusion, we provide compelling evidence that the combination ofSalmonellatype III-mediated antigen delivery and CpG immunization is an attractive novel vaccination strategy to modulate CD8 differentiation patterns toward distinct antigen-specific T-cell subsets with favorable protective capacities.
Effect of the O-Antigen Length of Lipopolysaccharide on the Functions of Type III Secretion Systems in
Salmonella enterica
Authors: Hölzer Stefanie U. , Schlumberger Markus C. , Jäckel Daniela , Hensel Michael
Published: September 2009

The virulence of
Salmonella enterica
critically depends on the functions of two type III secretion systems (T3SS), with the
Salmonella
pathogenicity island 1 (SPI1)-encoded T3SS required for host cell invasion and the SPI2-T3SS enabling
Salmonella
to proliferate within host cells. A further T3SS is required for the assembly of the flagella. Most serovars of
Salmonella
also possess a lipopolysaccharide with a complex O-antigen (OAg) structure. The number of OAg units attached to the core polysaccharide varies between 16 and more than 100 repeats, with a trimodal distribution. This work investigated the correlation of the OAg length with the functions of the SPI1-T3SS and the SPI2-T3SS. We observed that the number of repeats of OAg units had no effect on bacterial motility. The interaction of
Salmonella
with epithelial cells was altered if the OAg structure was changed by mutations in regulators of OAg. Strains defective in synthesis of very long or long and very long OAg species showed increased translocation of a SPI1-T3SS effector protein and increased invasion. Invasion of a strain entirely lacking OAg was increased, but this mutant strain also showed increased adhesion. In contrast, translocation of a SPI2-T3SS effector protein and intracellular replication were not affected by modification of the OAg length. Mutant strains lacking the entire OAg or long and very long OAg were highly susceptible to complement killing. These observations indicate that the architecture of the outer membrane of
Salmonella
is balanced to permit sufficient T3SS function but also to confer optimal protection against antimicrobial defense mechanisms.
Effects of Acid pH Shock on Phosphate Concentrations and Microbial Phosphate Uptake in an Acidifying and a Circumneutral Lake
Authors: Nalewajko C. , O'Mahony M. A.
Published: September 2009

Water samples from Plastic Lake and St. Nora Lake, Dorset, Ontario, were subjected to a rapid decrease in pH (acid pH shock). In both lakes, phosphate concentrations changed following pH shock. Minimal phosphate concentrations were observed in the pH 5.2–5.8 range. Maximal concentrations in both lakes occurred at pH 4.0: in Plastic Lake the mean increase at pH 4 was 3.0 times ambient and in St. Nora Lake was 2.5 times ambient. Particles > 0.45 μm were the major source of the phosphate released on acid pH shock. Rate constants of 32PO4 uptake by microorganisms decreased in response to acid pH shock, and bacteria were affected more than algae; the decrease in rate constants was more severe in Plastic than in St. Nora Lake but we could not distinguish the relative contributions of H+ toxicity and isotope dilution (by the extra phosphate released) to the observed decline.
Evidence for Antifreeze Protein Gene Transfer in Atlantic Salmon (Salmo salar)
Authors: Fletcher Garth L. , Shears Margaret A. , King Madonna J. , Davies Peter L. , Hew Choy L.
Published: September 2009

Atlantic salmon (Salmo salar) freeze to death if they come into contact with ice at water temperatures below −0.7 °C. Consequently, sea-pen culture of this species in cold water is severely limited. Winter flounder (Pseudopleuronectes americanus) survive in ice-laden seawater by producing a set of antifreeze polypeptides (AFP). We are attempting to make the Atlantic salmon more freeze resistant by transferring antifreeze protein genes from the winter flounder to the genome of the salmon. Salmon eggs were microinjected with linearized DNA after fertilization. Individual fingerlings (1–2 g) were analyzed for flounder AFP genes by genomic Southern blotting. DNA from 2 out of 30 fingerlings showed hybridization to the flounder DNA probe. Hybridization bands following cleavage by restriction enzymes Sst l and Bam HI were identical to those of the injected DNA. Hybridization following Hind III digestion indicated that the flounder AFP gene was linked to the salmon genome. These hybridization signals were absent in the DNA from control fish. The intensity of the hybridization signals indicated that there was on average at least one copy of the AFP gene present per cell.
Comparative Ecology and Behavior of Domestic, Hybrid, and Wild Strains of Brook Trout, Salvelinus fontinalis, after Stocking
Authors: Lachance Stephanie , Magnan Pierre
Published: September 2009

Two years after planting in six small oligotrophic lakes, domestic, hybrid and wild strains of brook trout, Salvelinus fontinalis, used space and food resources in the same way as native trout. Although trout living with or without white sucker, Catostomus commersoni, were similarly spatially distributed, they had different diets, suggesting a feeding niche shift of trout in the presence of sucker; we concluded that this shift is under phenotypic control because each planted strain came from similar genetic backgrounds. Sexual maturity was related to the size of individuals, regardless of the strain, and males matured before females. Almost all males and females were sexually mature in the first fall after stocking except wild females (3.0 and 75% matured during the first and second fall, respectively). Gonadosomatic indices (GSI) of domestic and hybrid females were similar during the first fall, but the GSI of domestic females was significantly higher than that of hybrid and wild strains in the second fail. Mean egg diameters were similar among the three strains during the two falls, but fecundity of domestic females, after correction for size differences, was significantly higher than that of hybrid females which, in turn, was significantly higher than that of wild ones.
Experimental Infection of Rainbow Trout, Oncorhynchus mykiss, with Contracaecum osculatum (Rudolphi, 1802) and Pseudoterranova decipiens (Krabbe, 1878) (Nematoda; Ascaridoidea)
Authors: Smith J. W. , Elarifi A. E. , Wootten R. , Pike A. W. , Burt M. D. B.
Published: September 2009

The fate of freshly hatched larvae of the marine ascaridoid nematodes Contracaecum osculatum and Pseudoterranova decipiens (from grey seals, Halichoerus grypus, from Scotland and the Canadian Atlantic) was investigated following oral or intraperitoneal introduction into rainbow trout, Oncorhynchus mykiss, maintained at 7–13 °C in fresh water. Neither species appeared to survive for long in the trout alimentary tract following oral introduction; a few larvae were found alive after 2 d but none after 21 d. intraperitoneally, P. decipiens did not survive beyond 21 d, but some C. osculatum exsheathed and developed over several months to lengths over 13 mm, and morphologically and morphometrically resembled third-stage larvae from naturally infected whiting, Merlangius merlangus, from the northern North Sea; no moult was detected. Thus, freshly hatched free-living larvae of C. osculatum are able to develop directly to the third stage in the body cavity of a fish without earlier passage through a crustacean or other invertebrate host.
A Comparison of Methods for Assessment of Nutrient Deficiency of Phytoplankton in a Large Oligotrophic Lake
Authors: Dodds Walter K. , Priscu John C.
Published: September 2009

Short-term (h) and Song-term (d) changes in phytoplankton community physiology and bsomass in response to nutrient enrichment were used concomitantly as bioassays of phytoplankton nutrient deficiency in oligotrophic Flathead Lake, Montana, six times over the course of a year. Long-term bioassays consisted of nutrient amendments to epilimnetic water in 20 L containers which were subsequently monitored for algal growth. Short-term bioassays included measurement of NH4+ stimulation of dark carbon fixation, measurement of PO43− and NH4+ uptake over time to assess depletion of internal pools and stimulation effects of PO43− on NH4+ uptake and NH4+ on PO43− uptake. During thermal stratification, simultaneous additions of NH4+ and PO43− in long-term bioassays caused significant increases in chlorophyll a concentration, photosynthetic 14CO2 uptake, and particulate N concentration within 4.5 d; single additions of NH4+ or PO43− had little or no effect. During winter mixing there was little evidence for N or P deficiency in either short- or long-term bioassays. In general, short-term bioassays did not consistently agree with each other or with long-term bioassays. Our results suggest that it may be necessary to elicit growth of phytoplankton with nutrient addition to make definitive statements regarding nutrient deficiency.
Light, Nutrients, and Water Temperature as Determinants of Phytoplankton Production in Two Saline, Prairie Lakes with High Sulphate Concentrations
Authors: Robarts Richard D. , Evans Marlene S. , Arts Michael T.
Published: September 2009

Our data support empirical models indicating that algal productivity is low relative to total phosphorus (TP) levels in prairie lakes with high sulphate concentrations. Mean chlorophyll accounted for 91.1% of the variance in euphotic zone primary production (ΣA) in Humboldt Lake (total dissolved solids (TDS) = 3.3 g∙L−1; Zmax = 6 m), while TP, total dissolved phosphorus, and water temperature accounted for 82.7% of ΣA variance in Redberry Lake (TDS = 20.9 g∙L−1; Zmax = 17 m). The relative importance of these variables to ΣA resulted from biological, chemical, and physical differences of these lakes. Light usually penetrated to the bottom of Redberry Lake due to a mean euphotic zone (Zeu) chlorophyll of 1.7 mg∙m−3, while Humboldt Lake's mean Zeu was 3.4 m with a mean chlorophyll concentration of 62.6 mg∙m−3. Chlorophyll was the dominant factor correlated with light penetration in Humboldt Lake (r2 = 0.65) but not in Redberry Lake. Photosynthetic capacity was correlated (r2 = 0.72) with water temperature only in Redberry Lake. The mean ΣA was 57.1 and 230.2 mg C∙m−2∙h−1 for Redberry and Humboldt lakes, respectively.
Factors Limiting Primary Productivity in Lake Ontario Tributaries Receiving Salmon Migrations
Authors: Rand Peter S. , Hall Charles A. S. , McDowell William H. , Ringler Neil H. , Kennen Jonathan G.
Published: September 2009

Many tributary streams of Lake Ontario have become important spawning habitats for introduced Pacific salmon. We examine how phosphorus released through salmon decomposition and other environmental factors potentially limit primary productivity in two Lake Ontario tributaries in New York State. Contribution of phosphorus (measured as total phosphorus) from salmon carcasses, computed as the percentage of the estimated phosphorus discharged from the stream, was very low (< 1%∙yr−1), but of modest importance (> 50%∙d−1) during restricted periods in the spring. Experimental results from three stream sites demonstrated that phosphorus, which is present naturally at high concentrations, is not limiting primary productivity during the period that the salmon are in the streams. Finally, results from an analysis of 15 free-water oxygen studies indicate that the streams are productive (gross primary production 0.9–10.2 g O2∙m−2∙d−1) and that light appears to limit stream primary productivity more than nutrients. We conclude that salmon migrations are unlikely to substantially increase the rate of primary productivity in these already fertile streams.
Population Genetic Structure of the Armorhead,Pseudopentaceros wheeleri, in the North Pacific Ocean: Application of the Polymerase Chain Reaction to Fisheries problems
Authors: Martin Andrew P. , Humphreys Robert , Palumbi Stephen R.
Published: September 2009

Armorhead (Pseudopentaceros wheeleri) occur in the subarctic, epipelagic habitats of the northern Pacific Ocean and are known to reproduce on seamounts in the central Pacific. Over the last few decades, overexploitation of seamount populations led to dramatic declines in abundances of reproductive populations. We undertook a study of the population genetics of armorhead to test whether distinct stocks exist in association with specific seamounts. We used the polymerase chain reaction (PCR) and a combination of DNA sequencing and restriction fragment length polymorphism (RFLP) analysis to analyze mtDNA variants for individuals collected from three localities: two seamounts and from the open ocean. We discovered that mtDNA haplotypes are not partitioned geographically, refuting the hypothesis that different seamounts harbor genetically distinct populations. Furthermore, genetic similarity of seamount and open-ocean fish supports the hypothesis that armorhead migrate between the central and northern Pacific Ocean for reproduction and feeding, respectively.
ONE-DIMENSIONAL MODEL OF SOMITIC CELLS POLARIZATION IN A BISTABILITY WINDOW OF EMBRYONIC MESODERM
Authors: PETROV VALKO , TIMMER JENS
Published: September 2009

The considerations are based on the understanding that somitic cells polarization in bistability window of embryonic (pre-somitic) mesoderm is a dynamical process. It occurs in the form of a polarization wavefront of somite cells spread in anterior–posterior direction of the embryonic mesoderm. It is assumed that a macroscopic cell polarization has a bistable behavior corresponding to the molecular mechanism of bistability window formation. Moreover this type of polarization is supposed to be transmittable to the other cells by contact interaction. At the end, a volume of polarized cells is taken, which is able to create mechanical tension in the volume of nonpolarized neighbor cells and to inhibit their polarization. On this basis we explore the leading aspect of somitogenesis robustness by considering a simple wavefront model of polarization and analyzing its propagation in terms of the standard methods of qualitative theory of differential equations. The obtained theoretical results are interpreted in the context of their possible experimental verification.
SOME ESTIMATES FOR POLYNOMIALS
Authors: Honda Tatsuhiro , Miyagi Mitsuhiro , Nishihara Masaru , Ohgai Seiko , Yoshida Mamoru
Published: September 2009

We give an elementary alternative proof of the Bernstein inequalities and the Szegö inequalities for trigonometric polynomials or polynomials.
SEPARATING LINEAR MAPS OF CONTINUOUS FIELDS OF BANACH SPACES
Authors: Leung Chi-Wai , Tsai Chung-Wen , Wong Ngai-Ching
Published: September 2009

In this paper, we give a complete description of the structure of separating linear maps between continuous fields of Banach spaces. Some automatic continuity results are obtained.
NORM OF SUMS OF PEIRCE PROJECTIONS
Authors: Zalar Borut
Published: September 2009

Peirce projections P1, P1/2 and P0 are one of the fundamental technical tools in the theory of JB *-triples. It is well known that all three of them are contractive. We show that the sum of two Peirce projections need not be contractive. We also give the upper estimate for the norm of such a sum, valid in all JC *-triples, and present a conjecture of the exact value of this norm, based on some numerical experiments.
Computer-supported access control
Authors: Stevens Gunnar , Wulf Volker
Published: September 2009

Traditionally, access control is understood as a purely technical mechanism which rejects or accepts access attempts automatically according to a specific preconfiguration. However, such a perspective neglects the practices of access control and the embeddedness of technical mechanisms within situated action. In this article, we reconceptualize the issue of access control on a theoretical, methodological, and practical level. On a theoretical level, we develop a terminology to distinguish between access control practices and the technical support mechanisms. We coin the term Computer Supported Access Control (CSAC) to emphasize this perspective. On a methodological level, we discuss empirical investigations of access control behavior from a situated action perspective. We discovered a differentiated set of social practices around traditional access control systems. By applying these findings to a practical level, we enhance the design space of computer supported access control mechanisms by suggesting a matrix of technical mechanisms which go beyond an ex-ante configuration.