bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Pricing of Mortgage Insurance Premiums Under Systematic and Idiosyncratic Shocks
Authors: Pu Ming , Fan Gang‐Zhi , Ban Chunsheng 
Published: August 2014

AbstractThe recent financial crisis has posed new challenges to the pricing issue of mortgage insurance premiums. By extending an option‐based approach to this pricing issue, we attempt to tackle several key challenges including the clustering of mortgage defaults, the diversification effect of underlying property pools, and mortgage insurers' information advantages. Our model partitions the volatility of collateralized property prices into idiosyncratic volatility and systematic volatility. Our results demonstrate that although the rising number of pooled mortgage loans can reduce the volatility of average default losses, the increasing correlation between the collateralized properties can lead to the volatility clustering of these losses.
Who is Changing Health Insurance Coverage? Empirical Evidence on Policyholder Dynamics
Authors: Christiansen Marcus C. , Eling Martin , Schmidt Jan‐Philipp , Zirkelbach Lorenz 
Published: August 2014

AbstractLong‐term health insurance contracts provide policyholders with the option of lapsing coverage or switching to another tariff within the same insurance company. We empirically analyze policyholder behavior regarding contract commitment in a large data set of German private health insurance contracts. We show that short‐term as well as long‐term premium development, along with premium adjustment frequency, affect lapse and tariff switch rates. Moreover, the sales channel has a strong impact on switching behavior, indicating that policyholder choice is not fully independent of sales representatives. Our results are important for risk assessment and risk management of portfolios of health insurance contracts and provide better understanding of the dynamics of policyholder behavior in health insurance.
The Cost of Counterparty Risk and Collateralization in Longevity Swaps
Authors: Biffis Enrico , Blake David , Pitotti Lorenzo , Sun Ariel 
Published: August 2014

AbstractDerivative longevity risk solutions, such as bespoke and indexed longevity swaps, allow pension schemes, and annuity providers to swap out longevity risk, but introduce counterparty credit risk, which can be mitigated if not fully eliminated by collateralization. We examine the impact of bilateral default risk and collateral rules on the marking to market of longevity swaps, and show how longevity swap rates must be determined endogenously from the collateral flows associated with the marking‐to‐market procedure. For typical interest rate and mortality parameters, we find that the impact of collateralization is modest in the presence of symmetric default risk, but more pronounced when default risk and/or collateral rules are asymmetric. Our results suggest that the overall cost of collateralization is comparable with, and often much smaller than, that found in the interest rate swaps market, which may then provide the appropriate reference framework for the credit enhancement of both indemnity‐based and indexed longevity risk solutions.
Pressure‐induced Vasodilation and Reactive Hyperemia at Different Depths in Sacral Tissue Under Clinically Relevant Conditions
Authors: Bergstrand Sara , Källman Ulrika , Ek Anna‐Christina , Lindberg Lars‐Göran , Engström Maria , Sjöberg Folke , Lindgren Margareta 
Published: August 2014

AbstractObjectiveTo characterize PIV and RH at different sacral tissue depths in different populations under clinically relevant pressure exposure.MethodsForty‐two subjects (<65 years), 38 subjects (≥65 years), and 35 patients (≥65 years) participated. Interface pressure, skin temperature, and blood flow at tissue depths of 1, 2, and 10 mm (using LDF and PPG) were measured in the sacral tissue before, during, and after load in a supine position.ResultsPressure‐induced vasodilation and RH were observed at three tissue depths. At 10 mm depth, the proportion of subjects with a lack of PIV was higher compared to superficial depths. The patients had higher interface pressure during load than the healthy individuals, but there were no significant differences in blood flow. Twenty‐nine subjects in all three study groups were identified with a lack of PIV and RH.ConclusionsPressure‐induced vasodilation and RH can be observed at different tissue depths. A lack of these responses was found in healthy individuals as well as in patients indicating an innate susceptibility in some individuals, and are potential important factors to evaluate in order to better understand the etiology of pressure ulcers.
Pretreatment of Human Cerebrovascular Endothelial Cells with CO‐releasing Molecule‐3 Interferes with JNK/AP‐1 Signaling and Suppresses LPS‐induced Proadhesive Phenotype
Authors: Serizawa Fukashi , Patterson Eric , Potter Richard F. , Fraser Douglas D. , Cepinskas Gediminas 
Published: August 2014

AbstractObjectiveExogenously administered CO interferes with PMN recruitment to the inflamed organs. The mechanisms of CO‐dependent modulation of vascular proadhesive phenotype, a key step in PMN recruitment, are unclear.MethodsWe assessed the effects/mechanisms of CO liberated from a water‐soluble CORM‐3 on modulation of the proadhesive phenotype in hCMEC/D3 in an in vitro model of endotoxemia. To this end, hCMEC/D3 were stimulated with LPS (1 μg/mL) for six hours. In some experiments hCMEC/D3 were pretreated with CORM‐3 (200 μmol/L) before LPS‐stimulation. PMN rolling/adhesion to hCMEC/D3 were assessed under conditions of laminar shear stress (0.7 dyn/cm2). In parallel, expression of adhesion molecules E‐selectin, ICAM‐1, and VCAM‐1 (qPCR), activation of transcription factors, NF‐κB and AP‐1 (ELISA), and MAPK‐signaling (expression/phosphorylation of p38, ERK1/2, and JNK1/2; western blot) were assessed.ResultsThe obtained results indicate that CORM‐3 pretreatment reduces PMN rolling/adhesion to LPS‐stimulated hCMEC/D3 (p < 0.05). Decreased PMN rolling/adhesion to hCMEC/D3 was associated with CORM‐3‐dependent inhibition of MAPK JNK1/2 activation (Tyr‐phosphorylation), inhibition of transcription factor, AP‐1 (c‐Jun phosphorylation), and subsequent suppression of VCAM‐1 expression (p < 0.05).ConclusionsThese findings indicate that CORM‐3 pretreatment interferes with JNK/AP‐1 signaling and suppresses LPS‐induced upregulation of the proadhesive phenotype in hCMEC/D3.
Plant defence suppression is mediated by a fungal sirtuin during rice infection by Magnaporthe oryzae
Authors: Fernandez Jessie , Marroquin‐Guzman Margarita , Nandakumar Renu , Shijo Sara , Cornwell Kathryn M. , Li Gang , Wilson Richard A. 
Published: August 2014

SummaryCrop destruction by the hemibiotrophic rice pathogen Magnaporthe oryzae requires plant defence suppression to facilitate extensive biotrophic growth in host cells before the onset of necrosis. How this is achieved at the genetic level is not well understood. Here, we report that a M. oryzae sirtuin, MoSir2, plays an essential role in rice defence suppression and colonization by controlling superoxide dismutase (SOD) gene expression. Loss of MoSir2 function in Δsir2 strains did not affect appressorial function, but biotrophic growth in rice cells was attenuated. Compared to wild type, Δsir2 strains failed to neutralize plant‐derived reactive oxygen species (ROS) and elicited robust defence responses in rice epidermal cells that included elevated pathogenesis‐related gene expression and granular depositions. Deletion of a SOD‐encoding gene under MoSir2 control generated Δsod1 deletion strains that mimicked Δsir2 for impaired rice defence suppression, confirming SOD activity as a downstream output of MoSir2. In addition, comparative protein acetylation studies and forward genetic analyses identified a JmjC domain‐containing protein as a likely target of MoSir2, and a Δsir2 Δjmjc double mutant was restored for MoSOD1 expression and defence suppression in rice epidermal cells. Together, this work reveals MoSir2 and MoJmjC as novel regulators of early rice cell infection.
Substrate recognition by the bacterial type II secretion system: more than a simple interaction
Authors: Pineau Camille , Guschinskaya Natalia , Robert Xavier , Gouet Patrice , Ballut Lionel , Shevchik Vladimir E. 
Published: August 2014

SummaryType II secretion system (T2SS) is a multiprotein trans‐envelope complex that translocates fully folded proteins through the outer membrane of Gram‐negative bacteria. Although T2SS is extensively studied in several bacteria pathogenic for humans, animals and plants, the molecular basis for exoprotein recruitment by this secretion machine as well as the underlying targeting motifs remain unknown. To address this question, we used bacterial two‐hybrid, surface plasmon resonance, in vivo site‐specific photo‐cross‐linking approaches and functional analyses. We showed that the fibronectin‐like Fn3 domain of exoprotein PelI from Dickeya dadantii interacts with four periplasmic domains of the T2SS components GspD and GspC. The interaction between exoprotein and the GspC PDZ domain is positively modulated by the GspD N1 domain, suggesting that exoprotein secretion is driven by a succession of synergistic interactions. We found that an exposed 9‐residue‐long loop region of PelI interacts with the GspC PDZ domain. This loop acts as a specific secretion signal that controls exoprotein recruitment by the T2SS. Concerted in silico and in vivo approaches reveal the occurrence of equivalent secretion motifs in other exoproteins, suggesting a plausible general mechanism of exoprotein recruitment by the T2SS.
Mechanism of mate detection in parasitoid wasps: sound and vibratory cues change with the developmental progress of future mates inside host pupal cases
Authors: Danci Adela , Inducil Cesar , Takács Stephen , Schaefer Paul W. , Gries Gerhard 
Published: August 2014

AbstractInsects including parasitoid wasps use acoustic and vibratory signals in the context of sexual communication, mate recognition, courtship and mating. Males of the parasitoid wasp Pimpla disparis Viereck (Hymenoptera: Ichneumonidae) detect insect host pupae parasitized by a conspecific female, learn their location, visit them repeatedly and remain on or near them when the prospective mate nears emergence. In the present study, the acoustic and vibratory cues that males exploit to detect the presence and track the developmental progress of a future mate inside a host pupal case are investigated. Responses are acquired from developing parasitoids (DePa) by airborne sound and laser Doppler vibrometer recordings, after gently stimulating each of 20 wax moth host pupae with a paintbrush on days 1–23 post parasitism. Sound and vibratory cues produced by DePa are detectable from day 7 onward and relate mostly to spinning movements. Parameters of sound and vibratory cues (amplitude, dominant frequency, upper limit of frequency band) change significantly over time and thus could ‘inform’ a visiting adult male about the stage of development of DePa. Adult males antennating a parasitized pupa and flying around it also induce vibrations, which in turn may inform DePa about the presence of a male. There is no experimental evidence for true signalling and rapid information exchange between DePa and adult males. Delaying reply signals may help DePa avoid attacks by illicit receivers of such signals, including female (hyper)parasitoids and invertebrate predators.
Self‐aggregation of Synthetic Zinc Chlorophyll Derivatives Possessing 31‐Hydroxy or Methoxy Group and 131‐Mono‐ or Dicyanomethylene Moiety in Nonpolar Organic Solvents as Models of Chlorosomal Bacteriochlorophyll‐d Aggregates
Authors: Tamiaki Hitoshi , Kuno Masaki , Ohata Masaki 
Published: August 2014

AbstractMethyl 131‐(di)cyanomethylene‐pyropheophorbides were synthesized by Knoevenagel reactions of the corresponding 131‐oxo‐chlorins prepared from modifying chlorophyll‐a with malononitrile or cyanoacetic acid. Alternatively, methyl 131‐cyanomethylene‐pyropheophorbides were produced by Wittig reactions of 131‐oxo‐chlorins with Ph3P=CHCN. Self‐aggregation of zinc complexes of the semi‐synthetic chlorophyll derivatives possessing a hydroxy or methoxy group at the 31‐position was examined in 1%(v/v) tetrahydrofuran or dichloromethane and hexane by electronic absorption and circular dichroism spectroscopy. Although intermolecular hydrogen‐bonding between the 31‐hydroxy and 131‐oxo groups of bacteriochlorophylls‐c/d/e/f was essential for their self‐aggregation in natural light‐harvesting antenna systems (=chlorosomes), zinc 31‐hydroxy‐131‐di/monocyanomethylene‐chlorins self‐aggregated in the less/lesser polar organic solvents to form chlorosome‐like large oligomers in spite of lacking the 131‐oxo moiety as the hydrogen‐bonding acceptor. Zinc 31‐methoxy‐131‐dicyanomethylene‐chlorin gave similar self‐aggregates regardless of lack of both the 31‐hydroxy and 131‐oxo groups. The present self‐aggregation was ascribable to stronger coordination of the 31‐oxygen atom to the central zinc than the conventional systems, where the electron‐withdrawing cyano group(s) increased the coordinative ability of the central zinc through the chlorin π‐system.
Xa39, a novel dominant gene conferring broad‐spectrum resistance to Xanthomonas oryzae pv. oryzae in rice
Authors: Zhang F. , Zhuo D.‐L. , Zhang F. , Huang L.‐Y. , Wang W.‐S. , Xu J.‐L. , Vera Cruz C. , Li Z.‐K. , Zhou Y.‐L. 
Published: August 2014

Bacterial blight (BB), caused by Xanthomonas oryzae pv. oryzae (Xoo), is one of the most devastating rice diseases worldwide. In this study, a rice introgression line (IL), FF329, which was identified from a BC1F4 population derived from the cross between donor PSBRC66 (P66) and recipient Huang‐Hua‐Zhan (HHZ), exhibited a typical hypersensitive response (HR) when inoculated with all 21 representative Xoo strains, consisting of 14 Philippines races and seven Chinese pathotypes. By contrast, the parents were highly susceptible to 10 of the tested strains and resistant or moderately susceptible to 11 strains, but without HR symptoms. Genetic analysis of the F2 population derived from the HHZ/FF329 cross with virulent Philippines race 6 (P6) and Chinese pathotype V (CV) revealed that BB resistance in FF329 was controlled by a single dominant gene. Because FF329 showed broad‐spectrum BB resistance, different from both parents, the gene identified was novel and was designated Xa39. Two SSR markers, RM21 and RM206, located on rice chromosome 11, were linked to the target gene by bulked segregant analysis. A further six markers linked to Xa39 were identified in the region between RM21 and RM206 for fine gene mapping, and the Xa39 locus was refined to a 97·4 kb interval flanked by markers RM26985 and DM13 using a large F2 population. This gene provides rice breeders with a new option to incorporate BB resistance into newly developed cultivars.
Goal‐directed EEG activity evoked by discriminative stimuli in reinforcement learning
Authors: Luque David , Morís Joaquín , Rushby Jacqueline A. , Le Pelley Mike E. 
Published: August 2014

AbstractIn reinforcement learning (RL), discriminative stimuli (S) allow agents to anticipate the value of a future outcome, and the response that will produce that outcome. We examined this processing by recording EEG locked to S during RL. Incentive value of outcomes and predictive value of S were manipulated, allowing us to discriminate between outcome‐related and response‐related activity. S predicting the correct response differed from nonpredictive S in the P2. S paired with high‐value outcomes differed from those paired with low‐value outcomes in a frontocentral positivity and in the P3b. A slow negativity then distinguished between predictive and nonpredictive S. These results suggest that, first, attention prioritizes detection of informative S. Activation of mental representations of these informative S then retrieves representations of outcomes, which in turn retrieve representations of responses that previously produced those outcomes.
Carbon status and structural stability of soils from differing land use systems in the Kingdom of Tonga
Authors: Manu V. , Whitbread A. , Blair N. , Blair G. 
Published: August 2014

AbstractMaintenance of soil carbon stocks is vital for the environment at large and for maintenance of soil chemical, physical and biological fertility. Tonga represents a country in agricultural transition from subsistence to commercial production and whilst this is good for the national economy the impact on soil resources is less clear. The major cropped soils, fallow vegetation types and forest systems of Tonga were identified in each island group and samples of representative soils (0.15 m depth) from each land use unit were taken. Total carbon (CT) and δ13C were measured and labile carbon (CL) determined by oxidation with 333 mm KMnO4. These data were used to determine the carbon management index (CMI) and the proportion of carbon from C4 species in the CT pool. Relative to primary forest, the soil CT and CL generally declined with changes in vegetation and more intense mechanical tillage. The contribution of C4 plants to soil C increased with intensity of mechanical tillage and the prevalence of C4 guinea grass (Panicum maximum Jacquin) fallow. The changes in soil C were reflected in the CMI, and CL was a more sensitive indicator of change than CT. These data indicates that all land use systems have experienced a large net loss of soil C relative to the forest systems. Soil mean weight diameter (MWD) decreased significantly with increased intensity of mechanical tillage and to a lesser extent with the intensity and length of cropping. The relationship between soil MWD and soil C was similar with soil CT and CL. Grass fallow was as effective as permanent vegetation systems in improving soil MWD and lowering the micro‐aggregate (<125 μm) fraction.
A pilot study to develop an objective clinical score for canine otitis externa
Authors: Nuttall Tim , Bensignor Emmanuel 
Published: August 2014

BackgroundThe lack of an accepted clinical scoring system in canine otitis externa makes it difficult to compare clinical trials.Hypothesis/ObjectivesTo develop a score that is clinically relevant, reliable and sensitive to change.AnimalsClient‐owned healthy dogs (n = 55) and dogs with otitis externa (n = 60).MethodsWe compared 0–3 and 0–5 assessments of erythema, oedema/swelling, erosion/ulceration, exudate and pain of the ear canals with a reference 0–2 scale. Additional data included odour, pruritus scores, tympanic membrane condition, treatment outcome and neutrophil, bacterial and Malassezia counts.ResultsThere were no significant differences between the vertical and horizontal canal scores (correlation coefficients >0.93). Correlation coefficients for the 0–3 and 0–5 scales were also >0.9 for all parameters, but the 0–2 scale was more variable. Pain and pruritus did not correlate well with the lesion scores and were associated with suppurative and erythroceruminous otitis, respectively. Neutrophil and microbial counts were variable and could not be used to generate cut‐off values to differentiate healthy and affected ears or determine the response to therapy. Total scores ≥4 differentiated affected from healthy ears with 91.1% sensitivity and 100% specificity; scores ≤3 were 100% sensitive and 91.9% specific for clinical success. The intra‐ and interobserver reliability was high (intraclass correlation coefficients >0.95 and Cohen's kappa coefficients >0.65).Conclusions and clinical importanceThis pilot study showed that the 0–3 Otitis Index Score (OTIS3) for erythema, oedema/swelling, erosion/ulceration and exudate is suitable for further validation by a larger group of clinicians.
Defining Gene-Phenotype Relationships in Acinetobacter baumannii through One-Step Chromosomal Gene Inactivation
Authors: Tucker Ashley T. , Nowicki Emily M. , Boll Joseph M. , Knauf Gregory A. , Burdis Nora C. , Trent M. Stephen , Davies Bryan W. 
Published: August 2014

ABSTRACT

Rates of infection with hospital-acquired
Acinetobacter baumannii
have exploded over the past decade due to our inability to limit persistence and effectively treat disease.
A. baumannii
quickly acquires antibiotic resistance, and its genome encodes mechanisms to tolerate biocides and desiccation, which enhance its persistence in hospital settings. With depleted antibiotic options, new methods to treat
A. baumannii
infections are desperately needed. A comprehensive understanding detailing
A. baumannii
cellular factors that contribute to its resiliency at genetic and mechanistic levels is vital to the development of new treatment options. Tools to rapidly dissect the
A. baumannii
genome will facilitate this goal by quickly advancing our understanding of
A. baumannii
gene-phenotype relationships. We describe here a recombination-mediated genetic engineering (recombineering) system for targeted genome editing of
A. baumannii
. We have demonstrated that this system can perform directed mutagenesis on wide-ranging genes and operons and is functional in various strains of
A. baumannii
, indicating its broad application. We utilized this system to investigate key gene-phenotype relationships in
A. baumannii
biology important to infection and persistence in hospitals, including oxidative stress protection, biocide resistance mechanisms, and biofilm formation. In addition, we have demonstrated that both the formation and movement of type IV pili play an important role in
A. baumannii
biofilm.

IMPORTANCE
Acinetobacter baumannii
is the causative agent of hospital-acquired infections, including pneumonia and serious blood and wound infections.
A. baumannii
is an emerging pathogen and has become a threat to public health because it quickly develops antibiotic resistance, making treatment difficult or impossible. While the threat of
A. baumannii
is well recognized, our understanding of even its most basic biology lags behind. Analysis of
A. baumannii
cellular functions to identify potential targets for drug development has stalled due in part to laborious genetic techniques. Here we have pioneered a novel recombineering system that facilitates efficient genome editing in
A. baumannii
by single PCR products. This technology allows for rapid genome editing to quickly ascertain gene-phenotype relationships. To demonstrate the power of recombineering in dissecting
A. baumannii
biology, we use this system to establish key gene-phenotype relationships important to infection and persistence in hospitals, including oxidative stress protection, biocide resistance, and biofilm formation.