bluuebunny/crossref_metadata_2025 huggingface dataset:
HIGH‐ORDER SHORT‐TIME EXPANSIONS FOR ATM OPTION PRICES OF EXPONENTIAL LÉVY MODELS
Authors: Figueroa‐López José E. , Gong Ruoting , Houdré Christian
Published: May 2014

The short‐time asymptotic behavior of option prices for a variety of models with jumps has received much attention in recent years. In this work, a novel second‐order approximation for at‐the‐money (ATM) option prices is derived for a large class of exponential Lévy models with or without Brownian component. The results hereafter shed new light on the connection between both the volatility of the continuous component and the jump parameters and the behavior of ATM option prices near expiration. In the presence of a Brownian component, the second‐order term, in time‐t, is of the form , with d2 only depending on Y, the degree of jump activity, on σ, the volatility of the continuous component, and on an additional parameter controlling the intensity of the “small” jumps (regardless of their signs). This extends the well‐known result that the leading first‐order term is . In contrast, under a pure‐jump model, the dependence on Y and on the separate intensities of negative and positive small jumps are already reflected in the leading term, which is of the form . The second‐order term is shown to be of the form and, therefore, its order of decay turns out to be independent of Y. The asymptotic behavior of the corresponding Black–Scholes implied volatilities is also addressed. Our method of proof is based on an integral representation of the option price involving the tail probability of the log‐return process under the share measure and a suitable change of probability measure under which the pure‐jump component of the log‐return process becomes a Y‐stable process. Our approach is sufficiently general to cover a wide class of Lévy processes, which satisfy the latter property and whose Lévy density can be closely approximated by a stable density near the origin. Our numerical results show that the first‐order term typically exhibits rather poor performance and that the second‐order term can significantly improve the approximation's accuracy, particularly in the absence of a Brownian component.
DO ARBITRAGE‐FREE PRICES COME FROM UTILITY MAXIMIZATION?
Authors: Siorpaes Pietro
Published: May 2014

In this paper we ask whether, given a stock market and an illiquid derivative, there exists arbitrage‐free prices at which a utility‐maximizing agent would always want to buy the derivative, irrespectively of his own initial endowment of derivatives and cash. We prove that this is false for any given investor if one considers all initial endowments with finite utility, and that it can instead be true if one restricts to the endowments in the interior. We show, however, how the endowments on the boundary can give rise to very odd phenomena; for example, an investor with such an endowment would choose not to trade in the derivative even at prices arbitrarily close to some arbitrage price.
A FIRST‐ORDER BSPDE FOR SWING OPTION PRICING
Authors: Bender Christian , Dokuchaev Nikolai
Published: May 2014

We study an optimal control problem related to swing option pricing in a general non‐Markovian setting in continuous time. As a main result we uniquely characterize the value process in terms of a first‐order nonlinear backward stochastic partial differential equation and a differential inclusion. Based on this result we also determine the set of optimal controls and derive a dual minimization problem.
UTILITY MAXIMIZATION UNDER MODEL UNCERTAINTY IN DISCRETE TIME
Authors: Nutz Marcel
Published: May 2014

We give a general formulation of the utility maximization problem under nondominated model uncertainty in discrete time and show that an optimal portfolio exists for any utility function that is bounded from above. In the unbounded case, integrability conditions are needed as nonexistence may arise even if the value function is finite.
Thresholds Between, Worlds Apart
Authors: Burnham Scott
Published: May 2014

In the Adagio from Schubert's String Quintet, music of otherworldly bearing frames and encloses an utterly contrasting music of churning turmoil. The analysis offered in this article addresses those passages that connect and mediate this contrast: the sighing codetta to the first section which makes an impossibly poignant fuss before coming to a close in E major; the trill which whisks the action from there into F minor; the stunning broken‐off harmonies which form the retransition back to the opening; the brief flare of F minor right before the movement's final cadence.

These threshold passages are then compared to various spots within the rest of the Quintet, such as the way that the Trio section relates to the Scherzo, or the use of prominent semitonal manoeuvres at the opening of the first movement and the close of the finale. The essay concludes with some reflections on the ways Schubert's thresholds can be heard to invoke the plight of mortality or to suggest a loss of faith in a stable reality.
Asymptomatic post‐transplant lymphoproliferative disorder diagnosed at one year protocol renal allograft biopsy
Authors: Kitajima Kazuki , Sasaki Hideo , Koike Junki , Nakazawa Ryuto , Sato Yuichi , Yazawa Masahiko , Tsuruoka Kayo , Kawarazaki Hiroo , Imai Naohiko , Shirai Sayuri , Shibagaki Yugo , Chikaraishi Tatsuya
Published: May 2014

Post‐transplant lymphoproliferative disorder (PTLD) is a neoplastic complication with a potentially fatal outcome that develops as a consequence of immunosuppression, and is mainly associated with Epstein‐Barr virus (EBV) infection. A 70‐year‐old woman underwent a live unrelated, ABO‐incompatible renal transplant for end‐stage renal disease. One year after transplantation, protocol biopsy revealed pathological changes indicative of the histological subtype of ‘early lesions of PTLD’ according to the World Health Organization classification, while the patient showed no clinical signs or symptoms. The patient was finally diagnosed with EBV‐positive PTLD by in situ hybridization for EBER (EBV‐encoded RNA), and was successfully treated based on the reduction of immunosuppression. Protocol biopsy within the first post‐transplant year is the only diagnostic measure to detect asymptomatic early PTLD, which allows for early intervention and leads to better outcomes.
De novo proteinuria with pathological evidence of glomerulonephritis after everolimus induction
Authors: Miura Masayoshi , Yanai Mitsuru , Fukasawa Yuichiro , Higashiyama Hiroshi , Ito Yosuke , Tamaki Tohru
Published: May 2014

A 68‐year‐old man who underwent living‐unrelated kidney transplantation from his spousal donor was immunosuppressed with tacrolimus and mycophenolate mofetil. Despite his uneventful clinical course, protocol biopsy at 2 years post transplant showed de novo CNI tubulotoxicity despite low tacrolimus exposure. Everolimus was added in order to discontinue TACER. However, prominent proteinuria impeded continuation of everolimus since biopsy showed diffuse glomerular endocapillary proliferation without C4d deposition. No donor‐specific antibody was detected. Pulse steroids were given and proteinuria returned to normal with histological reversal.
Proliferative glomerulonephritis with monoclonal immunoglobulin A light‐chain deposits in the renal allograft
Authors: Setoguchi Kiyoshi , Kawashima Yoichiro , Tokumoto Tadahiko , Toma Hiroshi , Mizoguchi Shogo , Horita Shigeru , Yamaguchi Yutaka , Tanabe Kazunari
Published: May 2014

We herein describe the unique case of a 59‐year‐old man who underwent living kidney transplantation for IgA nephropathy (IgAN) and developed progressive kidney failure associated with the appearance of proliferative glomerulonephritis. An early protocol biopsy revealed recurrent IgAN with mesangial IgA2 deposits restricted to a single immunoglobulin λ light‐chain isotype. Despite treatment with tonsillectomy and rituximab, the patient eventually lost his allograft 31 months after transplantation. Serum electrophoresis showed a monoclonal IgA pattern. This case might share common pathological characteristics with the newly described entity referred to as proliferative glomerulonephritis with monoclonal IgG deposits.
Current problems in screening, diagnosis and treatment of polyomavirus BK nephropathy
Authors: Masutani Kosuke
Published: May 2014

Polyomavirus BK nephropathy (BKVN) is an important infectious complication in kidney transplantation. Since graft survival in patients with BKVN is poor, current clinical practice focuses on screening for viral replication, and pre‐emptive reduction of immunosuppression in viraemic patients. Urinary cytology, nucleic acid testing of urine and/or plasma, and viral‐specific staining of biopsy specimens are necessary for diagnosis. Infected tubular cells show intranuclear inclusions, lysis or necrosis, and shedding into the tubular lumen. But such light microscopy findings are quite focally observed in many cases, and varying degrees of tubulointerstitial inflammation mimicking T‐cell‐mediated acute rejection make accurate diagnosis difficult. There is a histological classification of BKVN originally reported by the University of Maryland in 2001, and modified by American Society of Transplantation Infectious Disease Community of Practice, which focuses on interstitial inflammation and fibrosis. Another classification was proposed by the Banff Working Group in 2009 (Banff Working Proposal), which focuses on acute tubular injury instead of interstitial inflammation. The usefulness of the Banff Working Proposal is now under consideration with a multicenter study being conducted, but it has not yet reached a clear conclusion. In this review, the current screening strategies for the replication of BK virus, difficulties with diagnosis, histopathological classifications, treatments, and prognostic factors of BKVN are discussed.
Epithelial‐myoepithelial carcinoma arising in the palate: a rare case report and review of the literature
Authors: Kawamata A. , Yamane M. , Nakazato Y.
Published: May 2014

This report describes our recent experience with a case of epithelial‐myoepithelial carcinoma of the left palate and reviews previously reported cases of this rare malignancy. A 68‐year‐old woman presented with painless nodular swelling of the left hard palate. Histopathological and immunohistochemical analyses confirmed a diagnosis of epithelial‐myoepithelial carcinoma. We performed a partial maxillectomy through a lateral rhinotomy incision under general anaesthesia. During the surgery, the entire tumour mass was removed with clear surgical margins. The patient continued to undergo clinical follow‐up and radiological assessments for a period of 2.5 years with no evidence of recurrent or metastatic disease. Epithelial‐myoepithelial carcinoma is a rare malignancy that requires immunohistochemical validation of diagnosis and may be successfully treated with surgery alone.
The changing university business model: a stakeholder perspective
Authors: Miller Kristel , McAdam Maura , McAdam Rodney
Published: May 2014

Universities are in a current state of transition, whereby they are expected to develop a wide range of relationships with stakeholders in order to enhance regional innovation systems. However, despite external environmental pressures commonly regarded as one of the main drivers of business model evolution, there is a lack of studies that explore business model innovation as a result of multiple stakeholder influences. Accordingly, the aim of this paper is to examine the changing university business model within a region of the United Kingdom, using a stakeholder perspective that will aid theoretical development and refinement in both the business model and stakeholder fields. This examination is aided by consideration of the university business model as an activity system. Repeat interviews, combined with stakeholder theory, have been used to show how the changing university business model–stakeholder relationship has progressed through different stakeholder stages with resultant changes in content, structure and governance. Furthermore, conflicting objectives between each of the stakeholder groups (i.e. academics, industry liaison staff, technology transfer office staff and government support agency representatives) have led to the university business model evolving not as a process of co‐creation but rather in a series of transitions whereby multiple stakeholders are continually shaping the university business model through strategies that are dependent upon their salience. Finally, this paper contributes to the development and refinement of business model innovation research, in that the use of stakeholder constructs can illustrate the impact of multiple stakeholders' power and influence on business model innovation.
The fit between technological innovation and business model design for firm growth: evidence from China
Authors: Wei Zelong , Yang Dong , Sun Biao , Gu Meng
Published: May 2014

How does technological innovation fit with business model design to jointly impact firm growth? Given the increasingly salient role of business model, extant literature provides little answer to this question. This study builds a theoretical model based on technological innovation literature, business ecosystem theory, and business model literature to investigate this issue. This study finds that exploitative innovation and exploratory innovation fit with different business model designs to promote firm growth. Six hypotheses are proposed and examined by a database from 176 Chinese firms. This research finds that exploitative innovation has a negative whereas exploratory innovation has a positive effect on firm growth. More importantly, we find that efficiency‐centered business model design enhances the negative effect of exploitative innovation and weakens the positive effect of exploratory innovation. We also find that novelty‐centered business model design weakens the negative effect of exploitative innovation. This research contributes to both technological innovation and business model design literature.
Business model renewal and ambidexterity: structural alteration and strategy formation process during transition to a Cloud business model
Authors: Khanagha Saeed , Volberda Henk , Oshri Ilan
Published: May 2014

This paper presents the findings of a longitudinal study of a large corporation's transition to a new business model in the face of a major transformation in the ICT industry brought about by Cloud computing. We build theory on the process of business model innovation through a qualitative study that investigates how an established firm organizes for an emerging business model. Contrary to previous findings that presented spatial separation as the optimal structural approach for dealing with two competing business models, our findings indicate a need for recursive iterations between different modes of separated and integrated structures in line with the emergent nature of strategic intent toward the new business models. Our analyses reveal strategy formation to be a collective experimental learning process revolving around a number of alternative strategic intentions ranging from incremental evolution and transformation to complete replacement of the existing business model. Given the fundamental differences in the nature and requirements of those alternative intents, iterations between different structural modes and differing combinations proved to be crucial in enabling the organization to make transition to the new business model.
ATP citrate lyase activity is post‐translationally regulated by sink strength and impacts the wax, cutin and rubber biosynthetic pathways
Authors: Xing Shufan , van Deenen Nicole , Magliano Pasqualina , Frahm Lea , Forestier Edith , Nawrath Christiane , Schaller Hubert , Gronover Christian S. , Prüfer Dirk , Poirier Yves
Published: May 2014

Cytosolic acetyl‐CoA is involved in the synthesis of a variety of compounds, including waxes, sterols and rubber, and is generated by the ATP citrate lyase (ACL). Plants over‐expressing ACL were generated in an effort to understand the contribution of ACL activity to the carbon flux of acetyl‐CoA to metabolic pathways occurring in the cytosol. Transgenic Arabidopsis plants synthesizing the polyester polyhydroxybutyrate (PHB) from cytosolic acetyl‐CoA have reduced growth and wax content, consistent with a reduction in the availability of cytosolic acetyl‐CoA to endogenous pathways. Increasing the ACL activity via the over‐expression of the ACLA and ACLB subunits reversed the phenotypes associated with PHB synthesis while maintaining polymer synthesis. PHB production by itself was associated with an increase in ACL activity that occurred in the absence of changes in steady‐state mRNA or protein level, indicating a post‐translational regulation of ACL activity in response to sink strength. Over‐expression of ACL in Arabidopsis was associated with a 30% increase in wax on stems, while over‐expression of a chimeric homomeric ACL in the laticifer of roots of dandelion led to a four‐ and two‐fold increase in rubber and triterpene content, respectively. Synthesis of PHB and over‐expression of ACL also changed the amount of the cutin monomer octadecadien‐1,18‐dioic acid, revealing an unsuspected link between cytosolic acetyl‐CoA and cutin biosynthesis. Together, these results reveal the complexity of ACL regulation and its central role in influencing the carbon flux to metabolic pathways using cytosolic acetyl‐CoA, including wax and polyisoprenoids.
Hyperbaric oxygen for the treatment of nonhealing arterial insufficiency ulcers
Authors: Heyboer Marvin , Grant William D. , Byrne Joseph , Pons Paula , Morgan Monica , Iqbal Bilal , Wojcik Susan M.
Published: May 2014

There is limited data regarding hyperbaric oxygen's effectiveness in the treatment of nonhealing arterial insufficiency ulcers. This study was designed to analyze healing rates and amputation rates in patients who underwent adjunctive hyperbaric oxygen for a nonhealing arterial insufficiency ulcer. A retrospective chart review was completed on patients who underwent hyperbaric oxygen for arterial insufficiency ulcers that failed to heal despite standard treatment. Information collected included complete ulcer healing, amputation, and patient characteristics. There were 82 patients identified. A majority did not have diabetes (84.1%). The overall rate of healing was 43.9%. The overall major amputation rate was 17.1%. The amputation rate among those who healed was 0% compared to 42.4% among those not healed (p < 0.0001). Dialysis was predictive of major amputation (p = 0.03). Our findings suggest hyperbaric oxygen can play a role in management of arterial insufficiency ulcers that have failed standard treatment. The overwhelming majority of these patients did not have diabetes, which allows this study to be translated to patients with a primary arterial insufficiency ulcer. These results support the use of hyperbaric oxygen for select nonhealing arterial insufficiency ulcers that have failed standard therapy and the need for a prospective pilot study.
Genetic strain differences in the development of peritoneal fibroproliferative processes in mice
Authors: Marques Suzane M. , Castro Pollyana R. , Campos Paula P. , Viana Celso T. R. , Parreiras Patricia M. , Ferreira Mônica A. N. , Andrade Silvia P.
Published: May 2014

Fibroproliferative processes are regulated by a wide variety of tissue components and genetic factors. However, whether there are genetic differences in peritoneal fibroproliferative tissue formation, with consequent differences in response to drug treatment, is unclear. We characterize the influence of the genetic background on peritoneal fibroproliferative tissue induced by sponge implants in DBA/1, Swiss, C57BL/6, and BALB/c mouse strains. In addition, responses to dipyridamole in the implants were evaluated. Angiogenesis, assessed by intra‐implant hemoglobin content, was highest in Swiss mice, whereas levels of vascular endothelial growth factor were highest in C57BL/6 mice. The levels of pro‐inflammatory cytokines and of inflammatory enzymes (myeloperoxidase‐ and N‐acetyl‐β‐D‐glucosaminidase) were also strain‐related. The pro‐fibrogenic markers transforming growth factor beta‐1 and collagen were lowest in implants placed in DBA/1 mice, whereas those in C57BL/6 mice had the highest levels. Differential sensitivity to dipyridamole was also observed, with this compound being pro‐angiogenic in implants placed in DBA/1 mice but antiangiogenic in implants placed in Swiss. An overall anti‐inflammatory response was observed in the inbred strains. Antifibrogenic effects were observed only in implants placed in C57BL/6 mice. These important strain‐related differences in the development of peritoneal fibrosis and in response to dipyridamole must be considered in the design and analysis of studies on fibrogenesis in mice.
Effects of interleukin‐10 on cutaneous wounds and scars in humans of African continental ancestral origin
Authors: Kieran Ingrid , Taylor Catherine , Bush Jim , Rance Mark , So Karen , Boanas Adam , Metcalfe Anthony , Hobson Rosalind , Goldspink Nick , Hutchison John , Ferguson Mark
Published: May 2014

Scars in humans of African continental ancestry heal with an exaggerated inflammatory response and a generally wider scar. Interleukin‐10 is an anti‐inflammatory and antifibrotic cytokine. A randomized controlled trial in Caucasians found that exogenous interleukin‐10 resulted in improved macroscopic scar appearance and reduced scar redness. We investigated the effects of interleukin‐10 on cutaneous scarring in volunteers of African ancestral origin in an exploratory, single‐center, within‐subject, double‐blind randomized controlled trial. Fifty‐six subjects received two of four potential prerandomized concentrations of interleukin‐10 (5, 25, 100, and 250 ng/100 µL) in two full‐thickness incisions on the upper inner arms. Anatomically matching incisions on the contralateral arm were treated with placebo. Scars were excised at 1 month for histological analysis and were redosed with the same regimen. Resultant excision scars were followed up for 12 months for scar width measurement and scoring. Scoring was performed by trial doctors, subjects, and a panel. Incisions treated with 100 ng/100 µL interleukin‐10 had significantly reduced microscopic scar widths. Incisions treated with 5 and 25 ng/100 µL interleukin‐10 were also narrower, but not significantly. There were no differences observed in pro‐inflammatory or pro‐fibrotic markers between interleukin‐10 and placebo treatment. There was no long‐term evidence that 100 ng/100 µL interleukin‐10 had a therapeutic effect on macroscopic scar width or appearance, as excisions treated with this concentration were significantly wider than placebo between 8 and 12 months of maturation. Doctors showed a trend toward favoring the macroscopic appearance of placebo‐treated excisions compared with those treated with 250 ng/100 µL interleukin‐10. Panelists scored placebo‐treated excisions as significantly better‐appearing than those treated with 250 ng/100 µL interleukin‐10. Doctors' scores showed a trend toward favoring treatment with 5 ng/100 µL interleukin‐10 at 10 and 11 months post‐excision. Subjects showed a trend toward favoring treatment with 5 ng/100 µL interleukin‐10 between 5 and 9 months postexcision. Analysis of images of markedly improved scars revealed a potential subset of responders among those treated with 5 ng/100 µL interleukin‐10. No concentration of interleukin‐10 produced a statistically significant improvement in scarring compared with placebo.
Combined Feedforward–Feedback Active Control of Road Noise Inside a Vehicle Cabin
Authors: Duan Jie , Li Mingfeng , Lim Teik C. , Lee Ming-Ran , Cheng Ming-Te , Vanhaaften Wayne , Abe Takeshi
Published: May 2014

Conventional active control of road noise inside a vehicle cabin generally uses a pure feedforward control system with the conventional filtered-x least mean square (FXLMS) algorithm. While it can yield satisfactory noise reduction when the reference signal is well correlated with the targeted noise, in practice, it is not always possible to obtain a reference signal that is highly coherent with a broadband response typically seen in road noise. To address this problem, an active noise control (ANC) system with a combined feedforward–feedback controller is proposed to improve the performance of attenuating road noise. To take full advantage of the feedforward control, a subband (SFXLMS) algorithm, which can achieve more noise attenuation over a broad frequency range, is used to replace the conventional FXLMS algorithm. Meanwhile, a feedback controller, based on internal model control (IMC) architecture, is introduced to reduce the road noise components that have strong response but are poorly correlated with the reference signals. The proposed combined feedforward–feedback ANC system has been demonstrated by a simulation model with six reference accelerometers, two control loudspeakers and one error microphone, using actual data measured from a test vehicle. Results show that the performance of the proposed combined controller is significantly better than using either a feedforward controller only or a feedback controller only, and is able to achieve about 4 dBA of overall sound pressure level reduction.
Aeroelastic Tailoring of Helicopter Blades
Authors: Cornette Donatien , Kerdreux Benjamin , Michon Guilhem , Gourinat Yves
Published: May 2014

The dynamic loads transmitted from the rotor to the airframe are responsible for vibrations, discomfort and alternate stress on components. A new and promising way to minimize vibration is to reduce dynamic loads at their source by performing an aeroelastic optimization of the rotor. This optimization uses couplings between the flapwise-bending motion and the torsion motion. The impacts of elastic couplings (composite anisotropy) and inertial couplings (center-of-gravity offset) on blade dynamic behavior and on dynamic loads are evaluated in this paper. First, analytical results, based on a purely linear modal approach, are given to understand the influence of these couplings on blade dynamic behavior. Then, a complete nonlinear aeroelastic model of the rotor, including elastic and inertial couplings, is derived. Finally, this last model is used to improve a simplified but representative blade (homogeneous beam with constant chord) and results are presented.
Time-resolved and excitation-dependent photoluminescence study of CdTe/MgCdTe double heterostructures grown by molecular beam epitaxy
Authors: Zhao Xin-Hao , DiNezza Michael J. , Liu Shi , Lin Su , Zhao Yuan , Zhang Yong-Hang
Published: May 2014

This Letter reports the optical properties of CdTe/MgCdTe double heterostructures grown by molecular beam epitaxy. Low-temperature photoluminescence shows strong band-to-band emission and very weak defect related peaks, indicating low defect densities. The measured Shockley–Read–Hall lifetimes range from 57 to 86 ns at room temperature for samples grown under different conditions. The material radiative recombination coefficient B in the recombination rate defined as R=AΔn+(1−γ)BΔn2+CΔn3 [Wang et al., Phys. Status Solidi B 244, 2740 (2007)] is evaluated to be 4.3 ± 0.5 × 10−9 cm3·s−1 with a photon recycling factor γ of 0.85 calculated based on the geometric structure of the samples.
Reconstituted Human TPC1 Is a Proton-Permeable Ion Channel and Is Activated by NAADP or Ca
2+
Authors: Pitt Samantha J. , Lam Andy K. M. , Rietdorf Katja , Galione Antony , Sitsapesan Rebecca
Published: May 2014

Stimuli that increase calcium or NAADP may promote proton release from the endosomes and lysosomes by activating TPC1.
Crowding Impairs Sperm Motility
Authors: VanHook Annalisa M.
Published: May 2014

A TGF-β ligand acts as a neuroendocrine signal that promotes sperm motility under favorable reproductive conditions.
Prevalence of Chlorhexidine-Resistant Methicillin-Resistant Staphylococcus aureus following Prolonged Exposure
Authors: Schlett Carey D. , Millar Eugene V. , Crawford Katrina B. , Cui Tianyuan , Lanier Jeffrey B. , Tribble David R. , Ellis Michael W.
Published: May 2014

Chlorhexidine has been increasingly utilized in outpatient settings to control methicillin-resistant
Staphylococcus aureus
(MRSA) outbreaks and as a component of programs for MRSA decolonization and prevention of skin and soft-tissue infections (SSTIs). The objective of this study was to determine the prevalence of chlorhexidine resistance in clinical and colonizing MRSA isolates obtained in the context of a community-based cluster-randomized controlled trial for SSTI prevention, during which 10,030 soldiers were issued chlorhexidine for body washing. We obtained epidemiological data on study participants and performed molecular analysis of MRSA isolates, including PCR assays for determinants of chlorhexidine resistance and high-level mupirocin resistance and pulsed-field gel electrophoresis (PFGE). During the study period, May 2010 to January 2012, we identified 720 MRSA isolates, of which 615 (85.4%) were available for molecular analysis, i.e., 341 clinical and 274 colonizing isolates. Overall, only 10 (1.6%) of 615 isolates were chlorhexidine resistant, including three from the chlorhexidine group and seven from nonchlorhexidine groups (
P
> 0.99). Five (1.5%) of the 341 clinical isolates and five (1.8%) of the 274 colonizing isolates harbored chlorhexidine resistance genes, and four (40%) of the 10 possessed genetic determinants for mupirocin resistance. All chlorhexidine-resistant isolates were USA300. The overall prevalence of chlorhexidine resistance in MRSA isolates obtained from our study participants was low. We found no association between extended chlorhexidine use and the prevalence of chlorhexidine-resistant MRSA isolates; however, continued surveillance is warranted, as this agent continues to be utilized for infection control and prevention efforts.
Antitrypanosomal Activity of Fexinidazole Metabolites, Potential New Drug Candidates for Chagas Disease
Authors: Bahia Maria T. , Nascimento Alvaro F. S. , Mazzeti Ana Lia , Marques Luiz F. , Gonçalves Karolina R. , Mota Ludmilla W. R. , Diniz Lívia de F. , Caldas Ivo S. , Talvani André , Shackleford David M. , Koltun Maria , Saunders Jessica , White Karen L. , Scandale Ivan , Charman Susan A. , Chatelain Eric
Published: May 2014

This study was designed to verify the
in vivo
efficacy of sulfoxide and sulfone fexinidazole metabolites following oral administration in a murine model of Chagas disease. Female Swiss mice infected with the Y strain of
Trypanosoma cruzi
were treated orally once per day with each metabolite at doses of 10 to 100 mg/kg of body weight for a period of 20 days. Parasitemia was monitored throughout, and cures were detected by parasitological and PCR assays. The results were compared with those achieved with benznidazole treatment at the same doses. Fexinidazole metabolites were effective in reducing the numbers of circulating parasites and protecting mice against death, compared with untreated mice, but without providing cures at daily doses of 10 and 25 mg/kg. Both metabolites were effective in curing mice at 50 mg/kg/day (30% to 40%) and 100 mg/kg/day (100%). In the benznidazole-treated group, parasitological cure was detected only in animals treated with the higher dose of 100 mg/kg/day (80%). Single-dose pharmacokinetic parameters for each metabolite were obtained from a parallel group of uninfected mice and were used to estimate the profiles following repeated doses. Pharmacokinetic data suggested that biological efficacy most likely resides with the sulfone metabolite (or subsequent reactive metabolites formed following reduction of the nitro group) following administration of either the sulfoxide or the sulfone and that prolonged plasma exposure over the 24-h dosing window is required to achieve high cure rates. Fexinidazole metabolites were effective in treating
T. cruzi
in a mouse model of acute infection, with cure rates superior to those achieved with either fexinidazole itself or benznidazole.
Five-Year Longitudinal Assessment (2008 to 2012) of E-101 Solution Activity against Clinical Target and Antimicrobial-Resistant Pathogens
Authors: Denys Gerald A. , Pillar Chris M. , Sahm Daniel F. , O'Hanley Peter , Stephens Jackson T.
Published: May 2014

This study summarizes the topical E-101 solution susceptibility testing results for 760 Gram-positive and Gram-negative target pathogens collected from 75 U.S. sites between 2008 and 2012 and 103 ESKAPE pathogens. E-101 solution maintained potent activity against all bacterial species studied for each year tested, with MICs ranging from <0.008 to 0.25 μg porcine myeloperoxidase (pMPO)/ml. These results confirm that E-101 solution retains its potent broad-spectrum activity against U.S. clinical isolates and organisms with challenging resistance phenotypes.
Deficiency of Double-Strand DNA Break Repair Does Not Impair Mycobacterium tuberculosis Virulence in Multiple Animal Models of Infection
Authors: Heaton Brook E. , Barkan Daniel , Bongiorno Paola , Karakousis Petros C. , Glickman Michael S.
Published: May 2014

Mycobacterium tuberculosis
persistence within its human host requires mechanisms to resist the effector molecules of host immunity, which exert their bactericidal effects through damaging pathogen proteins, membranes, and DNA. Substantial evidence indicates that bacterial pathogens, including
M. tuberculosis
, require DNA repair systems to repair the DNA damage inflicted by the host during infection, but the role of double-strand DNA break (DSB) repair systems is unclear. Double-strand DNA breaks are the most cytotoxic form of DNA damage and must be repaired for chromosome replication to proceed.
M. tuberculosis
elaborates three genetically distinct DSB repair systems: homologous recombination (HR), nonhomologous end joining (NHEJ), and single-strand annealing (SSA). NHEJ, which repairs DSBs in quiescent cells, may be particularly relevant to
M. tuberculosis
latency. However, very little information is available about the phenotype of DSB repair-deficient
M. tuberculosis
in animal models of infection. Here we tested
M. tuberculosis
strains lacking NHEJ (a Δ
ku
Δ
ligD
strain), HR (a Δ
recA
strain), or both (a Δ
recA
Δ
ku
strain) in C57BL/6J mice, C3HeB/FeJ mice, guinea pigs, and a mouse hollow-fiber model of infection. We found no difference in bacterial load, histopathology, or host mortality between wild-type and DSB repair mutant strains in any model of infection. These results suggest that the animal models tested do not inflict DSBs on the mycobacterial chromosome, that other repair pathways can compensate for the loss of NHEJ and HR, or that DSB repair is not required for
M. tuberculosis
pathogenesis.
Identification of Lysine Residues in the Borrelia burgdorferi DbpA Adhesin Required for Murine Infection
Authors: Fortune Danielle E. , Lin Yi-Pin , Deka Ranjit K. , Groshong Ashley M. , Moore Brendan P. , Hagman Kayla E. , Leong John M. , Tomchick Diana R. , Blevins Jon S.
Published: May 2014

Decorin-binding protein A (DbpA) of
Borrelia burgdorferi
mediates bacterial adhesion to heparin and dermatan sulfate associated with decorin. Lysines K82, K163, and K170 of DbpA are known to be important for
in vitro
interaction with decorin, and the DbpA structure, initially solved by nuclear magnetic resonance (NMR) spectroscopy, suggests these lysine residues colocalize in a pocket near the C terminus of the protein. In the current study, we solved the structure of DbpA from
B. burgdorferi
strain 297 using X-ray crystallography and confirmed the existing NMR structural data.
In vitro
binding experiments confirmed that recombinant DbpA proteins with mutations in K82, K163, or K170 did not bind decorin, which was due to an inability to interact with dermatan sulfate. Most importantly, we determined that the
in vitro
binding defect observed upon mutation of K82, K163, or K170 in DbpA also led to a defect during infection. The infectivity of
B. burgdorferi
expressing individual
dbpA
lysine point mutants was assessed in mice challenged via needle inoculation. Murine infection studies showed that strains expressing
dbpA
with mutations in K82, K163, and K170 were significantly attenuated and could not be cultured from any tissue. Proper expression and cellular localization of the mutated DbpA proteins were examined, and NMR spectroscopy determined that the mutant DbpA proteins were structurally similar to wild-type DbpA. Taken together, these data showed that lysines K82, K163, and K170 potentiate the binding of DbpA to dermatan sulfate and that an interaction(s) mediated by these lysines is essential for
B. burgdorferi
murine infection.
Postgraduate anaesthesiology education: protocol for a scoping review
Authors: Ringsted Charlotte , Bance Sheena , Murgaski Laura Leigh , Herold Jodi , Glover Takahashi Susan
Published: May 2014

Introduction

The link between education and clinical practice is vital, yet the current state of research suggests there is a substantial gap between medical education research and practice. This too is the case in the domain of anaesthesiology education research, as much of the research focuses on simulation studies, and a narrow range of research methods. The aim of this study is to comprehensively review the existing literature in postgraduate anaesthesiology education research in order to identify key research priorities. The findings from this review will be used to establish a base for developing a strategic research programme in anaesthesia education and practice.

Methods and analysis

We will employ the scoping review methodology outlined by Arksey and O'Malley (2005) to comprehensively search the literature pertaining to postgraduate anaesthesiology education. We will search relevant electronic databases (eg, MEDLINE, EMBASE) and grey literature. After conducting calibration exercises, two authors will independently apply inclusion criteria to all titles and abstracts and perform full-text review of all eligible articles. Data to be extracted will include basic information about the study (eg, location, design) as well as detailed information regarding the context of the research and type of education examined. Our results will be used to develop a framework of themes that outline the research currently being conducted and identify gaps in research.

Ethics and dissemination

This review is the first step in a strategic research plan in postgraduate anaesthesiology education. We plan to disseminate this research through publications, presentations and meetings with relevant stakeholders. Ethical approval was not sought for this scoping review.
Differences in case-mix can influence the comparison of standardised mortality ratios even with optimal risk adjustment: an analysis of data from paediatric intensive care
Authors: Manktelow Bradley N , Evans T Alun , Draper Elizabeth S
Published: May 2014

Background and objective

The publication of clinical outcomes for consultant surgeons in 10 specialties within the NHS has, along with national clinical audits, highlighted the importance of measuring and reporting outcomes with the aim of monitoring quality of care. Such information is vital to be able to identify good and poor practice and to inform patient choice. The need to adequately adjust outcomes for differences in case-mix has long been recognised as being necessary to provide ‘like-for-like’ comparisons between providers. However, directly comparing values of the standardised mortality ratio (SMR) between different healthcare providers can be misleading even when the risk-adjustment perfectly quantifies the risk of a poor outcome in the reference population. An example is shown from paediatric intensive care.

Methods

Using observed case-mix differences for 33 paediatric intensive care units (PICUs) in the UK and Ireland for 2009–2011, SMRs were calculated under four different scenarios where, in each scenario, all of the PICUs were performing identically for each patient type. Each scenario represented a clinically plausible difference in outcome from the reference population.

Results

Despite the fact that the outcome for any patient was the same no matter which PICU they were to be admitted to, differences between the units were seen when compared using the SMR: scenario 1, 1.07–1.21; scenario 2, 1.00–1.14; scenario 3, 1.04–1.13; scenario 4, 1.00–1.09.

Conclusions

Even if two healthcare providers are performing equally for each type of patient, if their patient populations differ in case-mix their SMRs will not necessarily take the same value. Clinical teams and commissioners must always keep in mind this weakness of the SMR when making decisions.
Modelling the effects of habitat on self-thinning, energy equivalence, and optimal habitat structure for juvenile trout
Authors: Rosenfeld Jordan S.
Published: May 2014

Self-thinning theory predicts that decline in density with increasing individual mass should match the exponent of the metabolism–body mass relationship (∼0.9 in salmonids). However, self-thinning assumes energy equivalence (constant energy available to a cohort as it ages), which may be unrealistic for mobile taxa. I evaluate this assumption using a bioenergetic–stream habitat model to assess the sensitivity of available energy and self-thinning slopes to changes in habitat structure (percent pool). Self-thinning slopes across three age-classes of juvenile trout (young of the year, 1+, and 2+) were sensitive to both modelled habitat structure and density-independent mortality rates. Density-independent overwinter mortality generated self-thinning curves similar to those expected from metabolic allometry, even without habitat limitation (density-dependent mortality). Energy available to sympatric cohorts was unequal under most habitat configurations because of size-based differences in swimming performance that affected habitat availability and interference competition (dominance) that allowed resource monopolization by older cohorts. The optimal habitat structure that maximized abundance of the 2+ age-class (and best approximated energy equivalence) was ∼40% pool, but this value was sensitive to density-independent mortality rate and assumptions about the effect of the pool to riffle ratio on invertebrate prey production.
Growth and physiological responses to arbuscular mycorrhizal fungi and salt stress in dioecious plantPopulus tomentosa
Authors: Lu Yanwei , Wang Guangquan , Meng Qingjie , Zhang Wenhui , Duan Baoli
Published: May 2014

This study elucidated whether the beneficial effect of arbuscular mycorrhizal (AM) symbiosis was different in male and female Populus tomentosa Carrière trees. Female and male cuttings of P. tomentosa were treated with two AM fungal regimes, with or without an AM fungus (Glomus constrictum Trappe) inoculation, and with three salt regimes, no salt, low-salinity level (100 mmol·L–1NaCl), and high-salinity level (200 mmol·L–1NaCl). Our results showed that AM fungal colonization alleviated the salt-induced reduction in growth, gas exchange, photosynthetic pigment content, and nitrogen (N) and phosphorus (P) concentrations in the leaves, stems, and roots under low-salinity conditions. However, these effects were not alleviated under high-salinity conditions. AM fungal colonization was associated with a reinforcement of the activity of superoxide dismutase (SOD) and guaiacol peroxidase (GPx) and an inhibition of malondialdehyde (MDA) in treated plants of both genders under low-salinity conditions. Furthermore, sodium (Na+) and chlorine (Cl–) concentrations in tree organs were lower in the AM than the non-AM plants under the low-salinity condition in both sexes. AM fungal treatment may protect salt-stressed plants via the inhibition of salt-induced oxidative stress, which improves nutrient absorbance and inhibits Na+transport from the roots to the shoots. In addition, small differences in plant growth induced by AM fungal colonization were observed between sexes, but significant gender differences were obtained in other parameters such as SOD and GPx activities and N and P concentrations.
Inflammation in response to phytohemagglutinin injection in the Talas tuco-tuco (Ctenomystalarum): implications for the estimation of immunocompetence in natural populations of wild rodents
Authors: Merlo J.L. , Cutrera A.P. , Zenuto R.R.
Published: May 2014

The immunological variation in wild populations and its relation to life-history traits has recently become a central topic in the field of evolutionary biology, considering the critical contribution of immunity to an individual’s fitness. A common technique used by ecologists to estimate immunocompetence in wild populations is the phytohemagglutinin (PHA) – skin test. In this test, the degree of local swelling triggered by PHA is usually considered an estimate of T-lymphocyte activity, although there is an ongoing debate regarding this interpretation. Here, we coupled the PHA–skin test with a histological analysis to examine the temporal development of the cell-mediated response in the subterranean rodent Talas tuco-tuco (Ctenomys talarum Thomas, 1898). The inflammation response involved lymphocytes, neutrophils, eosinophils, and macrophages at the site of injection, achieving an increase of total leukocytes from 12 to 48 h after injection. However, the abundance of any of the leukocytes observed did not correlate with the degree of swelling at any time studied, suggesting that caution should be taken when interpreting the results of the PHA-induced swelling response. Particularly, the magnitude of macroscopic swelling should not be considered a priori as indicative of T-lymphocyte activity in wild-caught rodents. Our results highlight the importance of avoiding oversimplified approaches to measuring immunocompetence.
Change of concentrations and distributions of aluminum and manganese in tea leaves
Authors: Uomori Shun-Ya , Yamashita Hirofumi , Saito Manabu , Haruyama Yoichi , Yasuda Keisuke
Published: May 2014

In this paper, we measured the concentrations and spatial distributions of aluminum and manganese with the growing period of a tea leaf. Both elemental concentrations increased with the growing period and showed a rapid increase between five and six months. Aluminum showed clear localization in the epidermis with the growing period. Manganese did not show clear localization like aluminum throughout the growing period. The spatial correlation between aluminum and manganese were not observed.
Detection of lead in human hair: A contribution of PIXE to the lead-elimination issue
Authors: Murao S. , Kirdmanee C. , Sera K. , Goto S. , Takahashi C.
Published: May 2014

National Institute of Advanced Industrial Science and Technology is working for the Global Alliance to Eliminate Lead Paint (GAELP) of the United Nations Environment Program (UNEP), under the cooperation of Iwate Medical University Cyclotron Center and Nishina Memorial Cyclotron Center of Japan Radioisotope Association. In order to demonstrate how the PIXE is useful to monitor lead in human body, hair samples were collected from local communities and analyzed by the PIXE at the University together with the control of office workers. The analysis showed a clear anomaly of lead for factory workers. It is recommended that the PIXE be added as one of the instruments to assist UNEP's lead and other heavy metal studies.
Effects of some physical factors on the inhomogeneity in planar symmetry
Authors: Sharif M. , Bhatti M. Zaeem Ul Haq
Published: May 2014

This paper is devoted to identify some physical causes of energy density inhomogeneity and stability of self-gravitating relativistic fluids in plane symmetry such as Weyl tensor, local anisotropy, dissipative terms and their specific combination. We first develop a relationship between matter variables and the Weyl tensor and then formulate dynamical equations using Bianchi identities. For the non-dissipative dust fluid, we conclude that the system will remain homogeneous if and only if it is conformally flat which implies the shear-free condition. However, the converse is not true for the non-dissipative isotropic fluid. For non-dissipative anisotropic fluid, the inhomogeneity factor is identified to be one of the structure scalars. A particular case of geodesic with dissipation is also discussed.