bluuebunny/crossref_metadata_2025_split huggingface dataset:
An Analysis of the Economic Consequences of the Proportionate Liability Rule*
Authors: CHAN DEREK K. , PAE SUIL 
Published: April 2010

AbstractMajor accounting firms in the United States have singled out elimination of joint and several liability as one of the most needed legal reforms in the country. The recent legislation of the Private Securities Litigation Reform Act of 1995 replaced joint and several liability with proportionate liability. This paper develops a simple model to analyze the economic consequences of such a change in the legal environment facing public accountants. In particular, we examine the incentive effects induced by the proportionate liability rule on the auditor's effort and financial statement users' litigation decisions. Our analysis demonstrates that replacing joint and several liability with proportionate liability can decrease the equilibrium audit effort, lawsuit probability, market price of the firm, and audit fee. More important, even though the proportionate liability rule reduces the equilibrium audit effort, we show that it can actually increase social welfare.
Price and Volume Reactions to Public Information Releases: An Experimental Approach Incorporating Traders' Subjective Beliefs*
Authors: GILLETTE ANN B. , STEVENS DOUGLAS E. , WATTS SUSAN G. , WILLIAMS ARLINGTON W. 
Published: April 2010

AbstractThis paper examines how market prices, volume, and traders' dividend expectations respond to public information releases in laboratory markets for a long‐lived financial asset. The objective is to study deviations from the symmetric information risk‐neutral rational expectations (RE) benchmark, which predicts no trade in such settings. The results of a series of double‐auction and call markets are reported in which traders manage a portfolio of cash and asset shares over 15 rounds of trading. A public signal regarding the value of the liquidating dividend is released every third round, and traders' subjective expectations of the liquidating dividend are elicited each round as cash‐motivated forecasts. We find that, despite the public dividend signal, traders' dividend forecasts are heterogeneous. Forecasts and prices both underreact to the public signals, with prices under‐reacting more than forecasts. In general, price changes are not closely associated with public signals, and there is greater excess price volatility in double auctions than in call markets. Forty‐three percent of trades are inconsistent with the trader's forecasts, and inconsistent trades occur more frequently in the double‐auction markets. On average, approximately 10 percent of the outstanding shares are traded in each round, and trading volume is increasing in the mean absolute forecast revision and decreasing in the contemporaneous dispersion in forecasts. These results suggest that differential processing of the public signal and/or speculative trading for short‐term gain may help to explain why symmetric information RE predictions are often not supported in empirical and experimental settings. They also suggest that market reactions to public information releases may be influenced by market microstructure.
How many hosts? Modelling host breadth from field samples
Authors: Vesk Peter A. , McCarthy Michael A. , Moir Melinda L. 
Published: April 2010

Summary 1. Host‐specificity is important in fundamental and applied studies of biodiversity, but it is difficult to generate definitive data for many species. 2. Here, we present a model framework for estimating the realized host breadth of dependent fauna from samples collected from replicate host individuals. We use Bayesian, Zero‐inflated Poisson regression to model the abundance conditional upon host use – our focal parameter. We illustrate the model using a data set of insects on threatened and non‐threatened plant species from eastern Australia. Estimating co‐extinction risk through threats to host organisms is a key application for the model, requiring assessment of the host‐specificity of biota, whilst incorporating uncertainty. 3. The host breadth model indicated that several insect species had high probability of narrow host breadth, including several species that appeared to only have one host. Furthermore, the model distinguished polyphagous, oligophagous and monophagous insect species. Modification of the model to account for false positives also identified tourist occurrences. 4. The host breadth model can be utilized not only towards focusing conservation actions on the most co‐threatened dependent invertebrate species, but also for other projects involving host‐specificity, such as estimating the number of insects globally, and selecting the most likely candidates for biological control of invasive species. Further uses are likely in various data sets of associations between species.
Residues of intertwining operators for SO*6 as character identities
Authors: Shahidi Freydoon , Spallone Steven 
Published: April 2010

AbstractWe show that the residue at s=0 of the standard intertwining operator attached to a supercuspidal representation π⊗χ of the Levi subgroup GL2(F)×E1 of the quasisplit group SO*6(F) defined by a quadratic extension E/F of p-adic fields is proportional to the pairing of the characters of these representations considered on the graph of the norm map of Kottwitz–Shelstad. Here π is self-dual, and the norm is simply that of Hilbert’s theorem 90. The pairing can be carried over to a pairing between the character on E1 and the character on E× defining the representation of GL2(F) when the central character of the representation is quadratic, but non-trivial, through the character identities of Labesse–Langlands. If the quadratic extension defining the representation on GL2(F) is different from E the residue is then zero. On the other hand when the central character is trivial the residue is never zero. The results agree completely with the theory of twisted endoscopy and L-functions and determines fully the reducibility of corresponding induced representations for all s.
Specificity of Induction of the
vanA
and
vanB
Operons in Vancomycin-Resistant Enterococci by Telavancin
Authors: Hill Craig M. , Krause Kevin M. , Lewis Stacey R. , Blais Johanne , Benton Bret M. , Mammen Mathai , Humphrey Patrick P. , Kinana Alfred , Janc James W. 
Published: April 2010

ABSTRACT

Telavancin is a bactericidal, semisynthetic lipoglycopeptide indicated in the United States for the treatment of complicated skin and skin structure infections caused by susceptible Gram-positive bacteria and is under investigation as a once-daily treatment for nosocomial pneumonia. The related
vanA
and
vanB
gene clusters mediate acquired resistance to glycopeptides in enterococci by remodeling the dipeptide termini of peptidoglycan precursors from
d
-alanyl-
d
-alanine (
d
-Ala-
d
-Ala) to
d
-alanyl-
d
-lactate (
d
-Ala-
d
-Lac). In this study, we assessed the ability of telavancin to induce the expression of
van
genes in VanA- and VanB-type strains of vancomycin-resistant enterococci. Vancomycin, teicoplanin, and telavancin efficiently induced VanX activity in VanA-type strains, while VanX activity in VanB-type isolates was inducible by vancomycin but not by teicoplanin or telavancin. In VanA-type strains treated with vancomycin or telavancin, high levels of
d
-Ala-
d
-Lac-containing pentadepsipeptide were measured, while
d
-Ala-
d
-Ala pentapeptide was present at very low levels or not detected at all. In VanB-type strains, vancomycin but not telavancin induced high levels of pentadepsipeptide, while pentapeptide was not detected. Although vancomycin, teicoplanin, and telavancin induced similar levels of VanX activity in VanA-type strains, these organisms were more sensitive to telavancin, which displayed MIC values that were 32- and 128-fold lower than those of vancomycin and teicoplanin, respectively.
Macrolide and Clindamycin Resistance inStreptococcus milleriGroup Isolates from the Airways of Cystic Fibrosis Patients
Authors: Grinwis Margot E. , Sibley Christopher D. , Parkins Michael D. , Eshaghurshan Christina S. , Rabin Harvey R. , Surette Michael G. 
Published: April 2010

ABSTRACTOrganisms belonging to theStreptococcus millerigroup (SMG) are known for their role in pyogenic infections but have recently been implicated as etiological agents of pulmonary exacerbation in adult patients with cystic fibrosis (CF). The prolonged exposure of CF patients to antibiotics prompted us to investigate the susceptibility profiles of 118 SMG isolates from the airways of CF patients to 12 antibiotics compared to 43 SMG isolates from patients with invasive infections. We found that ∼60% of all isolates failed to grow using the standard medium for disc diffusion, Mueller-Hinton blood agar (MHBA), so we explored the usefulness of brain heart infusion (BHI) agar for susceptibility testing. Zone-of-inhibition comparisons between BHI and MHBA showed strong correlations for six antibiotics, and interpretations were similar for both medium types. For ceftriaxone and cefepime, both groups of isolates were highly susceptible. Tetracycline resistance levels were comparable between the two groups (22% in CF isolates and 17.4% in invasive isolates). However, more than half of the CF isolates were not susceptible to azithromycin, erythromycin, and clindamycin, compared to 11%, 13%, and 6.5% of invasive isolates, respectively. There were 5-fold and 8-fold increased risks of azithromycin and clindamycin resistance, respectively, for the isolates from the airways of CF patients relative to the invasive isolates. Macrolide resistance was strongly linked to chronic azithromycin therapy in CF patients. This study shows that BHI agar is a suitable alternative for antimicrobial susceptibility testing for the SMG and that SMG isolates from the airways of CF patients are more resistant to macrolides and clindamycin than strains isolated from patients with invasive infections.
Rapid Detection and Differentiation of Antibodies to HIV-1 and HIV-2 Using Multivalent Antigens and Magnetic Immunochromatography Testing
Authors: Granade Timothy C. , Workman Shon , Wells Susan K. , Holder Angela N. , Owen S. Michele , Pau Chou-Pong 
Published: April 2010

ABSTRACT

A simplified lateral-flow assay for the detection of antibodies to HIV using magnetic-bead conjugates and multibranched peptides from both HIV-1 and HIV-2 was developed. Magnetic immunochromatography testing (MICT) uses a standard lateral-flow platform that incorporates magnetic-bead conjugates for quantitative measurement of the magnetic field distortion associated with the bound magnetic conjugate (reported as adjusted relative magnetic units [MAR]). The results of the optimized MICT assay were compared to standard enzyme immunoassay (EIA) and Western blotting (WB) results using a blinded 649-member panel of specimens from the United States, Cameroon, and West Africa. The panel was comprised of samples from individuals infected with various HIV-1 subtypes (
n
= 234) or HIV-2 (
n
= 65) and HIV-seronegative specimens (
n
= 350). Additionally, 13 HIV-1 seroconversion panels (total specimens = 85), a worldwide panel containing seven of the major circulating HIV-1 subtypes (
n
= 18), an HIV-2 panel, an HIV-1/HIV-2 mixed panel, and 100 prospective specimens were tested with completely concordant results. Assay reproducibility (observed MAR) for both intra- and interrun testing was excellent, with coefficients of variation of <12%. MICT can provide a rapid, low-cost method of determining HIV antibody status requiring no subjective interpretations.
Cloning and Characterization of the Acidic Ribosomal Protein P2 ofCryptosporidium parvum, a New 17-Kilodalton Antigen
Authors: Priest Jeffrey W. , Kwon James P. , Montgomery Joel M. , Bern Caryn , Moss Delynn M. , Freeman Amanda R. , Jones Cara C. , Arrowood Michael J. , Won Kimberly Y. , Lammie Patrick J. , Gilman Robert H. , Mead Jan R. 
Published: April 2010

ABSTRACTCryptosporidiuminfection is commonly observed among children and immunocompromised individuals in developing countries, but large-scale outbreaks of disease among adults have not been reported. In contrast, outbreaks of cryptosporidiosis in the United States and Canada are increasingly common among patients of all ages. Thus, it seems likely that residents of regions whereCryptosporidiumis highly endemic acquire some level of immunity, while residents of the developed world do not. A new immunodominantCryptosporidium parvumantigen in the 15- to 17-kDa size range was identified as theCryptosporidium parvum60S acidic ribosomal protein P2 (CpP2). We developed a recombinant protein-based enzyme-linked immunosorbent assay for serologic population surveillance for antibodies that was 89% sensitive and 92% specific relative to the results of the large-format Western blot assay. The human IgG response is directed almost exclusively toward the highly conserved, carboxy-terminal 15 amino acids of the protein. Although IgG antibody cross-reactivity was documented with sera from patients with acute babesiosis, the development of an anti-CpP2 antibody response in our Peru study population correlated better withCryptosporidiuminfection than with infection by any other parasitic protozoan. In Haiti, the prevalence of antibodies to CpP2 plateaus at 11 to 20 years of age. Because anti-CpP2 IgG antibodies were found only among residents of countries in the developing world whereCryptosporidiuminfection occurs early and often, we propose that this response may be a proxy for the intensity of infection and for acquired immunity.
Construction and Immunological Evaluation of Multivalent Hepatitis B Virus (HBV) Core Virus-Like Particles Carrying HBV and HCV Epitopes
Authors: Sominskaya Irina , Skrastina Dace , Dislers Andris , Vasiljev Denis , Mihailova Marija , Ose Velta , Dreilina Dzidra , Pumpens Paul 
Published: April 2010

ABSTRACT

A multivalent vaccine candidate against hepatitis B virus (HBV) and hepatitis C virus (HCV) infections was constructed on the basis of HBV core (HBc) virus-like particles (VLPs) as carriers. Chimeric VLPs that carried a virus-neutralizing HBV pre-S1 epitope corresponding to amino acids (aa) 20 to 47 in the major immunodominant region (MIR) and a highly conserved N-terminal HCV core epitope corresponding to aa 1 to 60 at the C terminus of the truncated HBcΔ protein (N-terminal aa 1 to 144 of full-length HBc) were produced in
Escherichia coli
cells and examined for their antigenicity and immunogenicity. The presence of two different foreign epitopes within the HBc molecule did not interfere with its VLP-forming ability, with the HBV pre-S1 epitope exposed on the surface and the HCV core epitope buried within the VLPs. After immunization of BALB/c mice, specific T-cell activation by both foreign epitopes and a high-titer antibody response against the pre-S1 epitope were found, whereas an antibody response against the HBc carrier was notably suppressed. Both inserted epitopes also induced a specific cytotoxic-T-lymphocyte (CTL) response, as shown by the gamma interferon (IFN-γ) production profile.
Rapid Cytopathic Effects of
Clostridium perfringens
Beta-Toxin on Porcine Endothelial Cells
Authors: Gurtner Corinne , Popescu Francesca , Wyder Marianne , Sutter Esther , Zeeh Friederike , Frey Joachim , von Schubert Conrad , Posthaus Horst 
Published: April 2010

ABSTRACT

Clostridium perfringens
type C isolates cause fatal, segmental necro-hemorrhagic enteritis in animals and humans. Typically, acute intestinal lesions result from extensive mucosal necrosis and hemorrhage in the proximal jejunum. These lesions are frequently accompanied by microvascular thrombosis in affected intestinal segments. In previous studies we demonstrated that there is endothelial localization of
C. perfringens
type C β-toxin (CPB) in acute lesions of necrotizing enteritis. This led us to hypothesize that CPB contributes to vascular necrosis by directly damaging endothelial cells. By performing additional immunohistochemical studies using spontaneously diseased piglets, we confirmed that CPB binds to the endothelial lining of vessels showing early signs of thrombosis. To investigate whether CPB can disrupt the endothelium, we exposed primary porcine aortic endothelial cells to
C. perfringens
type C culture supernatants and recombinant CPB. Both treatments rapidly induced disruption of the actin cytoskeleton, cell border retraction, and cell shrinkage, leading to destruction of the endothelial monolayer
in vitro
. These effects were followed by cell death. Cytopathic and cytotoxic effects were inhibited by neutralization of CPB. Taken together, our results suggest that CPB-induced disruption of endothelial cells may contribute to the pathogenesis of
C. perfringens
type C enteritis.
A
Burkholderia pseudomallei
Δ
purM
Mutant Is Avirulent in Immunocompetent and Immunodeficient Animals: Candidate Strain for Exclusion from Select-Agent Lists
Authors: Propst Katie L. , Mima Takehiko , Choi Kyoung-Hee , Dow Steven W. , Schweizer Herbert P. 
Published: April 2010

ABSTRACT

Burkholderia pseudomallei
causes the disease melioidosis in humans and is classified as a category B select agent. Research utilizing this pathogen is highly regulated in the United States, and even basic studies must be conducted in biosafety level 3 (BSL-3) facilities. There is currently no attenuated
B. pseudomallei
strain available that is excluded from select-agent regulations and can be safely handled at BSL-2 facilities. To address this need, we created Bp82 and Bp190, which are Δ
purM
derivatives of
B. pseudomallei
strains 1026b and K96243 that are deficient in adenine and thiamine biosynthesis but replication competent
in vitro
in rich medium. A series of animal challenge studies was conducted to ensure that these strains were fully attenuated. Whereas the parental strains 1026b and K96243 and the complemented mutants Bp410 and Bp454 were virulent in BALB/c mice following intranasal inoculation, the Δ
purM
mutants Bp82 and Bp190 were avirulent even when they were administered at doses 4 logs higher than the doses used for the parental strains. Animals challenged with high doses of the Δ
purM
mutants rapidly cleared the bacterium from tissues (lung, liver, and spleen) and remained free of culturable bacteria for the duration of the experiments (up to 60 days postinfection). Moreover, highly susceptible 129/SvEv mice and immune incompetent mice (IFN-γ
−/−
, SCID) were resistant to challenges with Δ
purM
mutant Bp82. This strain was also avirulent in the Syrian hamster challenge model. We concluded that Δ
purM
mutant Bp82 is fully attenuated and safe for use under BSL-2 laboratory conditions and thus is a candidate for exclusion from the select-agent list.
Afa/Dr-Expressing, Diffusely AdheringEscherichia coliStrain C1845 Triggers F1845 Fimbria-Dependent Phosphatidylserine Externalization on Neutrophil-Like Differentiated PLB-985 Cells through an Apoptosis-Independent Mechanism
Authors: Sémiramoth Nicolas , Gleizes Aude , Turbica Isabelle , Sandré Catherine , Marin-Esteban Viviana , Gorges Roseline , Servin Alain , Chollet-Martin Sylvie 
Published: April 2010

ABSTRACTThe enterovirulentEscherichia colistrains potentially involved in inflammatory bowel diseases include diffusely adherent strains expressing Afa/Dr fimbriae (Afa/Dr DAEC). We have previously observed type 1 pilus-mediated interleukin-8 (IL-8) hyperproduction in infected neutrophils. As pathogen induction of host cell death programs and clearance of apoptotic infected cells are crucial for innate immune system homeostasis and host integrity, we examined modulation of neutrophil cell death by Afa/Dr DAEC. Using the human PLB-985 cell line differentiated into fully mature neutrophils, we found that the wild-type enterovirulentE. colistrain C1845 and the recombinant strain DH5α/pF1845 (expressing the fimbrial adhesin F1845) similarly induced time-dependent phosphatidylserine (PS) externalization, suggesting a major specific role of this virulence factor. Using small interfering RNA (siRNA) decay-accelerating factor (DAF)-transfected PLB-985 cells, we then showed that this PS externalization was triggered in part by glycosylphosphatidylinositol (GPI)-anchored DAF receptor engagement (leading to tyrosine kinase and protein kinase C activation) and that it required cytoskeleton and lipid raft architectural integrity. PS externalization under these conditions was not dependent on caspases, mitochondria, lysosomes, or reactive oxygen or nitrogen species. F1845-mediated PS externalization was sufficient to enable macrophage engulfment of infected differentiated PLB-985 cells. These findings provide new insights into the neutrophil response to Afa/Dr DAEC infection and highlight a new role for F1845 fimbriae. Interestingly, although apoptosis pathways were not engaged, C1845-infected PLB-985 cells displayed enhanced removal by macrophages, a process that may participate in the resolution of Afa/Dr DAEC infection and related inflammation.
Autoinducer-2 and QseC Control Biofilm Formation and
In Vivo
Virulence of
Aggregatibacter actinomycetemcomitans
Authors: Novak Elizabeth A. , Shao HanJuan , Daep Carlo Amorin , Demuth Donald R. 
Published: April 2010

ABSTRACT

Biofilm formation by the periodontal pathogen
Aggregatibacter actinomycetemcomitans
is dependent upon autoinducer-2 (AI-2)-mediated quorum sensing. However, the components that link the detection of the AI-2 signal to downstream gene expression have not been determined. One potential regulator is the QseBC two-component system, which is part of the AI-2-dependent response pathway that controls biofilm formation in
Escherichia coli
. Here we show that the expression of QseBC in
A. actinomycetemcomitans
is induced by AI-2 and that induction requires the AI-2 receptors, LsrB and/or RbsB. Additionally, inactivation of
qseC
resulted in reduced biofilm growth. Since the ability to grow in biofilms is essential for
A. actinomycetemcomitans
virulence, strains that were deficient in QseC or the AI-2 receptors were examined in an
in vivo
mouse model of periodontitis. The Δ
qseC
mutant induced significantly less alveolar bone resorption than the wild-type strain (
P
< 0.02). Bone loss in animals infected with the Δ
qseC
strain was similar to that in sham-infected animals. The Δ
lsrB
, Δ
rbsB
, and Δ
lsrB
Δ
rbsB
strains also induced significantly less alveolar bone resorption than the wild type (
P
< 0.03,
P
< 0.02, and
P
< 0.01, respectively). However, bone loss induced by a Δ
luxS
strain was indistinguishable from that induced by the wild type, suggesting that AI-2 produced by indigenous microflora in the murine oral cavity may complement the Δ
luxS
mutation. Together, these results suggest that the QseBC two-component system is part of the AI-2 regulon and may link the detection of AI-2 to the regulation of downstream cellular processes that are involved in biofilm formation and virulence of
A. actinomycetemcomitans
.