bluuebunny/crossref_metadata_2025 huggingface dataset:
Proteogenomic analysis of pathogenic yeast Cryptococcus neoformans using high resolution mass spectrometry
Authors: Nagarajha Selvan Lakshmi Dhevi , Kaviyil Jyothi Embekkat , Nirujogi Raja Sekhar , Muthusamy Babylakshmi , Puttamallesh Vinuth N , Subbannayya Tejaswini , Syed Nazia , Radhakrishnan Aneesha , Kelkar Dhanashree S , Ahmad Sartaj , Pinto Sneha M , Kumar Praveen , Madugundu Anil K , Nair Bipin , Chatterjee Aditi , Pandey Akhilesh , Ravikumar Raju , Gowda Harsha , Prasad Thottethodi Subrahmanya Keshava
Published: February 2014

Background

Cryptococcus neoformans, a basidiomycetous fungus of universal occurrence, is a significant opportunistic human pathogen causing meningitis. Owing to an increase in the number of immunosuppressed individuals along with emergence of drug-resistant strains, C. neoformans is gaining importance as a pathogen. Although, whole genome sequencing of three varieties of C. neoformans has been completed recently, no global proteomic studies have yet been reported.

Results

We performed a comprehensive proteomic analysis of C. neoformans var. grubii (Serotype A), which is the most virulent variety, in order to provide protein-level evidence for computationally predicted gene models and to refine the existing annotations. We confirmed the protein-coding potential of 3,674 genes from a total of 6,980 predicted protein-coding genes. We also identified 4 novel genes and corrected 104 predicted gene models. In addition, our studies led to the correction of translational start site, splice junctions and reading frame used for translation in a number of proteins. Finally, we validated a subset of our novel findings by RT-PCR and sequencing.

Conclusions

Proteogenomic investigation described here facilitated the validation and refinement of computationally derived gene models in the intron-rich genome of C. neoformans, an important fungal pathogen in humans.
Fixed points of set-valued Caristi-type mappings on semi-metric spaces via partial order relations
Authors: Nimana Nimit , Petrot Narin , Saksirikun Warut
Published: February 2014

In this paper, we present some fixed-point theorems that are related to a set-valued Caristi-type mapping. The main results extend the recent work which was presented by Jiang and Li (Fixed Point Theory Appl. 2013:74, 2013) from a single-valued setting to a set-valued case. Further, the presented results also improve essentially many results that have appeared, because we have removed some conditions from the auxiliary function. Meanwhile, we give some partial answers to an important problem which was raised by Kirk (Colloq. Math. 36:81-86, 1976).

MSC:47H10, 37C25.
Anti-inflammatory properties of a novel peptide interleukin 1 receptor antagonist
Authors: Klementiev Boris , Li Shizhong , Korshunova Irina , Dmytriyeva Oksana , Pankratova Stanislava , Walmod Peter S , Kjær Laura K , Dahllöf Mattias S , Lundh Morten , Christensen Dan P , Mandrup-Poulsen Thomas , Bock Elisabeth , Berezin Vladimir
Published: February 2014

Background

Interleukin 1 (IL-1) is implicated in neuroinflammation, an essential component of neurodegeneration. We evaluated the potential anti-inflammatory effect of a novel peptide antagonist of IL-1 signaling, Ilantide.

Methods

We investigated the binding of Ilantide to IL-1 receptor type I (IL-1RI) using surface plasmon resonance, the inhibition of Il-1β-induced activation of nuclear factor κB (NF-κB) in HEK-Blue cells that contained an IL-1β-sensitive reporter, the secretion of TNF-α in macrophages, protection against IL-1-induced apoptosis in neonatal pancreatic islets, and the penetration of Ilantide through the blood–brain barrier using competitive enzyme-linked immunosorbent assay (ELISA). We studied the effects of the peptide on social behavior and memory in rat models of lipopolysaccharide (LPS)- and amyloid-induced neuroinflammation, respectively, and its effect in a rat model of experimental autoimmune enchephalomyelitis.

Results

Ilantide bound IL-1RI, inhibited the IL-1β-induced activation of NF-κB, and inhibited the secretion of TNF-α in vitro. Ilantide protected pancreatic islets from apoptosis in vitro and reduced inflammation in an animal model of arthritis. The peptide penetrated the blood–brain barrier. It reduced the deficits in social activity and memory in LPS- and amyloid-treated animals and delayed the development of experimental autoimmune enchephalomyelitis.

Conclusions

These findings indicate that Ilantide is a novel and potent IL-1RI antagonist that is able to reduce inflammatory damage in the central nervous system and pancreatic islets.
Upregulation of Cystathionine-β-Synthetase Expression Contributes to Inflammatory Pain in Rat Temporomandibular Joint
Authors: Miao Xiuhua , Meng Xiaowen , Wu Geping , Ju Zhong , Zhang Hong-G , Hu Shufen , Xu Guang-Yin
Published: February 2014

Background:

Hydrogen sulfide (H2S), an endogenous gaseotransmitter/modulator, is becoming appreciated that it may be involved in a wide variety of processes including inflammation and nociception. However, the role for H2S in nociceptive processing in trigeminal ganglion (TG) neuron remains unknown. The aim of this study was designed to investigate whether endogenous H2S synthesizing enzyme cystathionine-β-synthetase (CBS) plays a role in inflammatory pain in temporomandibular joint (TMJ).

Methods:

TMJ inflammatory pain was induced by injection of complete Freund's adjuvant (CFA) into TMJ of adult male rats. Von Frey filaments were used to examine pain behavioral responses in rats following injection of CFA or normal saline (NS). Whole cell patch clamp recordings were employed on acutely isolated TG neurons from rats 2 days after CFA injection. Western blot analysis was carried out to measure protein expression in TGs.

Results:

Injection of CFA into TMJ produced a time dependent hyperalgesia as evidenced by reduced escape threshold in rats responding to VFF stimulation. The reduced escape threshold was partially reversed by injection of O-(Carboxymethyl) hydroxylamine hemihydrochloride (AOAA), an inhibitor for CBS, in a dose-dependent manner. CFA injection led to a marked upregulation of CBS expression when compared with age-matched controls. CFA injection enhanced neuronal excitability as evidenced by depolarization of resting membrane potentials, reduction in rheobase, and an increase in number of action potentials evoked by 2 and 3 times rheobase current stimulation and by a ramp current stimulation of TG neurons innervating the TMJ area. CFA injection also led to a reduction of IK but not IA current density of TG neurons. Application of AOAA in TMJ area reduced the production of H2S in TGs and reversed the enhanced neural hyperexcitability and increased the IK currents of TG neurons.

Conclusion:

These data together with our previous report indicate that endogenous H2S generating enzyme CBS plays an important role in TMJ inflammation, which is likely mediated by inhibition of IK currents, thus identifying a specific molecular mechanism underlying pain and sensitization in TMJ inflammation.
Single-base resolution of mouse offspring brain methylome reveals epigenome modifications caused by gestational folic acid
Authors: Barua Subit , Kuizon Salomon , Chadman Kathryn K , Flory Michael J , Brown W Ted , Junaid Mohammed A
Published: February 2014

Background

Epigenetic modifications, such as cytosine methylation in CpG-rich regions, regulate multiple functions in mammalian development. Maternal nutrients affecting one-carbon metabolism during gestation can exert long-term effects on the health of the progeny. Using C57BL/6 J mice, we investigated whether the amount of ingested maternal folic acid (FA) during gestation impacted DNA methylation in the offspring’s cerebral hemispheres. Reduced representation bisulfite sequencing at single-base resolution was performed to analyze genome-wide DNA methylation profiles.

Results

We identified widespread differences in the methylation patterns of CpG and non-CpG sites of key developmental genes, including imprinted and candidate autism susceptibility genes (P <0.05). Such differential methylation of the CpG and non-CpG sites may use different mechanisms to alter gene expressions. Quantitative real time reverse transcription-polymerase chain reaction confirmed altered expression of several genes.

Conclusions

These finding demonstrate that high maternal FA during gestation induces substantial alteration in methylation pattern and gene expression of several genes in the cerebral hemispheres of the offspring, and such changes may influence the overall development. Our findings provide a foundation for future studies to explore the influence of gestational FA on genetic/epigenetic susceptibility to altered development and disease in offspring.
Research on placebo analgesia is relevant to clinical practice
Authors: Gay Charles W , Bishop Mark D
Published: February 2014

Over the decades, research into placebo responses has shed light onto several endogenous (i.e. produced from within) mechanisms underlying modulation of pain perception initiated after the administration of inert substances (i.e. placebos). Chiropractors and manual therapists should embrace analgesic-placebo-research in an attempt to maximize clinical benefit. Historical views that placebo responses are fake, passive, undesirable, and require deception and therefore should be minimized and avoided in clinical practice are outdated. Further, statements that contend the placebo response represents a single mechanism are overly simplistic. This commentary will discuss research that shows that there are several active biological processes underlying modulation of pain perception involved in placebo analgesia and its counterpart nocebo hyperalgesia. We contend that it is highly likely that, to some extent, all of these biological processes are engaged, in varying degrees, following all interventions and represent endogenous pain modulating processes. Failure, of chiropractors and manual therapists, to embrace a more contemporary view of analgesic-placebo-research serves as a barrier to transferring knowledge into clinical practice and represents a missed opportunity to improve the delivery of current treatments.
Increased CD44s and decreased CD44v6 RNA expression are associated with better survival in myxofibrosarcoma patients: a pilot study
Authors: Matuschek Christiane , Lehnhardt Marcus , Gerber Peter Arne , Poremba Christopher , Hamilton Jackson , Lammering Guido , Orth Klaus , Budach Wilfried , Bojar Hans , Bölke Edwin , Peiper Matthias
Published: February 2014

Background

New prognostic markers may be of value in determining survival and informing decisions of adjuvant treatment in the heterogeneous group of soft tissue sarcomas known as malignant fibrous sarcomas (MFS). Increased CD44 expression has been associated with a better outcome in cancers such as bladder tumors and could potentially relate to cell-cell interaction as a marker for potential invasion/metastasis. The aim of this pilot study was to determine if there is a correlation between the expression rate of CD44 in adult patients with MFS and clinical outcomes.

Methods

The clinical outcome of 34 adult MFS patients (19 males and 15 females, average age 62 years, median 63 years, range: 38–88 years) who underwent surgical treatment were evaluated. Twenty-five of these patients had additional adjuvant radiotherapy. Extracted RNA from sarcoma tissues was used to measure the transcripts of CD44s (standard form) and isoform expression.

The pooled data for each variant of CD44 was divided in half at the median expression value into two equally sized groups (low and high). Survival modeling and multivariate analysis were used with these two groups to determine if there were differences in survival times and whether this was independent of known factors such as tumor stage/grade, patient age and resection margin status.

Results

High CD44s and low of CD44v6 expression significantly correlated with an improved outcome (P <0.05 and P <0.02, respectively) whereas CD44v8 and hCD44 (isoforms) did not. Differences in survival were apparent within 6–12 months of operation with >30% difference in survival between low/high expressions at 5 years. These finding were independent of the other measured MFS survival predictors, though the group was homogenous.

Conclusions

High CD44s and low CD44v6 expression may be an independent predictor of improved survival in MFS patients in this pilot data. This is contrary to other MFS data, which did not account for the CD44 isoforms but is confirmed by data from other cancer types. Further investigation is needed to confirm CD44 isoform expression data as a relevant survival biomarker and whether it could be used to inform clinical decisions such as adjuvant therapy.
Genome-wide analysis links emerin to neuromuscular junction activity in Caenorhabditis elegans
Authors: González-Aguilera Cristina , Ikegami Kohta , Ayuso Cristina , de Luis Alberto , Íñiguez María , Cabello Juan , Lieb Jason D , Askjaer Peter
Published: February 2014

Background

Laminopathies are diseases characterized by defects in nuclear envelope structure. A well-known example is Emery-Dreifuss muscular dystrophy, which is caused by mutations in the human lamin A/C and emerin genes. While most nuclear envelope proteins are ubiquitously expressed, laminopathies often affect only a subset of tissues. The molecular mechanisms underlying these tissue-specific manifestations remain elusive. We hypothesize that different functional subclasses of genes might be differentially affected by defects in specific nuclear envelope components.

Results

Here we determine genome-wide DNA association profiles of two nuclear envelope components, lamin/LMN-1 and emerin/EMR-1 in adult Caenorhabditis elegans. Although both proteins bind to transcriptionally inactive regions of the genome, EMR-1 is enriched at genes involved in muscle and neuronal function. Deletion of either EMR-1 or LEM-2, another integral envelope protein, causes local changes in nuclear architecture as evidenced by altered association between DNA and LMN-1. Transcriptome analyses reveal that EMR-1 and LEM-2 are associated with gene repression, particularly of genes implicated in muscle and nervous system function. We demonstrate that emr-1, but not lem-2, mutants are sensitive to the cholinesterase inhibitor aldicarb, indicating altered activity at neuromuscular junctions.

Conclusions

We identify a class of elements that bind EMR-1 but do not associate with LMN-1, and these are enriched for muscle and neuronal genes. Our data support a redundant function of EMR-1 and LEM-2 in chromatin anchoring to the nuclear envelope and gene repression. We demonstrate a specific role of EMR-1 in neuromuscular junction activity that may contribute to Emery-Dreifuss muscular dystrophy in humans.
voom: precision weights unlock linear model analysis tools for RNA-seq read counts
Authors: Law Charity W , Chen Yunshun , Shi Wei , Smyth Gordon K
Published: February 2014

New normal linear modeling strategies are presented for analyzing read counts from RNA-seq experiments. The voom method estimates the mean-variance relationship of the log-counts, generates a precision weight for each observation and enters these into the limma empirical Bayes analysis pipeline. This opens access for RNA-seq analysts to a large body of methodology developed for microarrays. Simulation studies show that voom performs as well or better than count-based RNA-seq methods even when the data are generated according to the assumptions of the earlier methods. Two case studies illustrate the use of linear modeling and gene set testing methods.
Psychiatric characteristics in transsexual individuals:
multicentre study in four European countries
Authors: Heylens Gunter , Elaut Els , Kreukels Baudewijntje P. C. , Paap Muirne C. S. , Cerwenka Susanne , Richter-Appelt Hertha , Cohen-Kettenis Peggy T. , Haraldsen Ira R. , De Cuypere Griet
Published: February 2014

Background

Research into the relationship between gender identity disorder and
psychiatric problems has shown contradictory results.

Aims

To investigate psychiatric problems in adults fulfilling DSM-IVTR
criteria for a diagnosis of gender identity disorder.

Method

Data were collected within the European Network for the Investigation of
Gender Incongruence using the Mini International Neuropsychiatric
Interview – Plus and the Structured Clinical Interview for DSM-IV Axis II
Disorders (n = 305).

Results

In 38% of the individuals with gender identity disorder a current
DSM-IV-TR Axis I diagnosis was found, mainly affective disorders and
anxiety disorders. Furthermore, almost 70% had a current and lifetime
diagnosis. All four countries showed a similar prevalence, except for
affective and anxiety disorders, and no difference was found between
individuals with early-onset and late-onset disorder. An Axis II
diagnosis was found in 15% of all individuals with gender identity
disorder, which is comparable to the general population.

Conclusions

People with gender identity disorder show more psychiatric problems than
the general population; mostly affective and anxiety problems are
found.
Interventions for reducing benzodiazepine use in older people: meta-analysis of randomised controlled trials
Authors: Gould Rebecca L. , Coulson Mark C. , Patel Natasha , Highton-Williamson Elizabeth , Howard Robert J.
Published: February 2014

Background

The use of benzodiazepines has been advised against in older people, but prevalence rates remain high.

Aims

To review the evidence for interventions aimed at reducing benzodiazepine use in older people.

Method

We conducted a systematic review, assessment of risk of bias and meta-analyses of randomised controlled trials of benzodiazepine withdrawal and prescribing interventions.

Results

Ten withdrawal and eight prescribing studies met the inclusion criteria. At post-intervention, significantly higher odds of not using benzodiazepines were found with supervised withdrawal with psychotherapy (odds ratio (OR) = 5.06, 95% CI 2.68–9.57,P<0.00001) and withdrawal with prescribing interventions (OR = 1.43, 95% CI 1.02–2.02,P=0.04) in comparison with the control interventions treatment as usual (TAU), education placebo, withdrawal with or without drug placebo, or psychotherapy alone. Significantly higher odds of not using benzodiazepines were also found for multifaceted prescribing interventions (OR = 1.37, 95% CI 1.10–1.72,P= 0.006) in comparison with control interventions (TAU and prescribing placebo).

Conclusions

Supervised benzodiazepine withdrawal augmented with psychotherapy should be considered in older people, although pragmatic reasons may necessitate consideration of other strategies such as medication review.
Psychological medicine and the future of
psychiatry
Authors: Sharpe Michael
Published: February 2014

Psychological medicine (liaison psychiatry) aims to integrate psychiatry
into other areas of medicine. It is currently enjoying considerable
expansion. The degree to which it can take advantage of this opportunity
will be important not only for its own future, but also for the survival of
psychiatry as a medical discipline.
Use of community treatment orders in an inner-London assertive outreach service
Authors: Rawala Muffazal , Gupta Susham
Published: February 2014

Aims and method

To compare admission rates and bed occupancy before and after the introduction of community treatment orders (CTOs) in 37 assertive outreach service patients. The effect of CTOs on treatment adherence and illicit drug use were also evaluated. The views of patients and care coordinators were obtained through a focus group.

Results

When CTOs were introduced, admission rates fell from 3.3 to 0.3 per year and average bed occupancy declined from 133.2 to 10.8 days per year. Treatment adherence improved from 4 (10.8%) to 31 (83.7%) patients, and an objective reduction in substance misuse was observed in 25 (67.5%) patients. Whereas patients expressed ambivalence towards CTOs, their care coordinators generally had a more positive view.

Clinical implications

The decline in hospital usage following the introduction of CTOs is encouraging and could reflect improved adherence and engagement through intensive case management, leading to a reduction in readmissions. However, further studies need to look at quality of life, cost-effectiveness and the impact on patients.
Blasphemy laws and mental illness in Pakistan
Authors: Husain Muzaffar
Published: February 2014

There is emerging evidence that individuals who are mentally ill are over-represented in the group of defendants prosecuted under the blasphemy laws of Pakistan. This article discusses the background of blasphemy legislation in Pakistan, and proposes causal interactions between underlying mental illness in the defendant and prosecution for blasphemy. It sketches possible legal safeguards for such blasphemy defendants with mental illness in mental health legislation.
Research productivity of staff in NHS mental health trusts: comparison using the Leiden method
Authors: Mitchell Alex J. , Gill John
Published: February 2014

Aims and method

To examine research productivity of staff working across 57 National Health Service (NHS) mental health trusts in England. We examined research productivity between 2010 and 2012, including funded portfolio studies and all research (funded and unfunded).

Results

Across 57 trusts there were 1297 National Institute for Health Research (NIHR) studies in 2011/2012, involving 46140 participants and in the same year staff in these trusts published 1334 articles (an average of only 23.4 per trust per annum). After correcting for trust size and budget, the South London and Maudsley NHS Foundation Trust was the most productive. In terms of funded portfolio studies, Manchester Mental Health and Social Care Trust as well as South London and Maudsley NHS Foundation Trust, Oxford Health NHS Foundation Trust and Cambridgeshire and Peterborough NHS Foundation Trust had the strongest performance in 2011/2012.

Clinical implications

Trusts should aim to capitalise on valuable staff resources and expertise and better support and encourage research in the NHS to help improve clinical services.
Neuroimaging in a memory assessment service: a completed audit cycle
Authors: Kuruvilla Tarun , Zheng Rui , Soden Ben , Greef Sarah , Lyburn Iain
Published: February 2014

Aims and method

A clinical audit was used to compare neuroimaging practice in a memory assessment service prior to and 6 months after implementation of guidance, developed from national and European guidelines and adapted to local resource availability, with multislice computed tomography (CT) as first-line structural imaging procedure.

Results

Referrals to the service nearly doubled from the initial audit to the re-audit. Patients having at least one neuroimaging procedure increased from 68 to 76%. Patients with no reason documented for not having imaging significantly reduced from 50% to less than 1%. Despite the larger number of referrals, the mean waiting times for the scans only increased from 22 to 30 days. Variations in practice between the sectors reduced.

Clinical implications

Disseminating evidence-based guidelines adapted to local resource availability appears to have standardised neuroimaging practice in a memory assessment service. Further research into the clinical and cost benefits of the increased scanning is planned.
Is the bark worse than the bite? Additional conditions used within community treatment orders
Authors: Smith Mike , Branton Tim , Cardno Alastair
Published: February 2014

Aims and method

To investigate the use of additional conditions attached to community treatment orders (CTOs) and whether they influence the process of recall to hospital. We conducted a retrospective descriptive survey of the records and associated paperwork of all the CTOs started in the trust in the year from January 2010. Each CTO was followed up for 12 months.

Results

A total of 65 CTOs were included in the study; 25 patients were recalled during the study and all but one of these had their CTO revoked and remained in hospital. Each patient whose CTO was revoked had experienced a relapse in their condition. Many patients had not complied with CTO conditions prior to relapsing and could potentially have been recalled earlier.

Clinical implications

Our findings suggest that the breaching of additional CTO conditions does not tend to result in a patient's recall to hospital. This has implications regarding how the workings of CTOs are explained to patients and regarding the utility of additional conditions more generally.
Community treatment orders: background and implications of the OCTET trial
Authors: Burns Tom , Molodynski Andrew
Published: February 2014

Community treatment orders (CTOs) were introduced into the UK despite unconvincing international evidence for their effectiveness. The Oxford Community Treatment Order Evaluation Trial (OCTET) is a multisite randomised controlled trial of 333 patients with psychosis conducted in the UK. It confirms an absence of any obvious benefit in reducing relapse despite significant curtailment of liberty. Community mental health teams need to seriously consider whether they should continue using CTOs or shift their clinical focus to strengthening the working alliance.
OCTET does not demonstrate a lack of effectiveness for community treatment orders
Authors: Curtis David
Published: February 2014

In the Oxford Community Treatment Order Evaluation Trial (OCTET), patients were randomised either to be made subject to a community treatment order (CTO) or to be managed with Section 17 leave and discharge. No differences in outcome between the two groups were observed. Here it is argued that the patients studied were not those who might have benefited from a CTO and that the psychiatrists involved were unlikely to have used the provisions of a CTO assertively. Consideration of the lengths of time for which both Section 17 leave and CTOs were used supports the notion that CTOs were not used appropriately for a group of patients who might have benefited from them. Hence the results of this study should not be taken to provide any evidence as to the effectiveness or otherwise of CTOs.
Open access publishing – a quiet revolution
Authors: Pimm Jonathan
Published: February 2014

Radical changes are taking place in scientific publishing, driven by mandates from major research funders both in the UK and elsewhere. The publishing landscape is changing, and open access is increasingly being seen as a viable alternative to subscription-based business models. Although many issues are yet unresolved, even the large commercial publishers are developing stables of open access journals. To reach a wider audience, and to increase appeal to potential contributors deciding where to publish, the Bulletin has now become an open access journal with effect from this issue.
Removal of Lipopolysaccharide and DNA from Protein Solutions Using Porous Supports Bearing Polymeric Lipid Membranes
Authors: Wakita Masa-aki
Published: February 2014

Polymeric lipid membranes of N-octadecylchitosan were covalently immobilized on porous supports and applied as adsorbents for purification of proteins. In addition to lipopolysaccharide, DNA was removed to its detection limit from albumin solution with a quantitative recovery of protein. Selective removal of lipopolysaccharide from IgG solution was also confirmed.
Theoretical Study on Alkoxydiphosphine Ligand for Bimetallic Cooperation in Nickel-catalyzed Monosubstitution of C–F Bond
Authors: Asako Sobi , Ilies Laurean , Verma Pritha , Ichikawa Saki , Nakamura Eiichi
Published: February 2014

A theoretical study on a tripodal alkoxydiphosphine (POP) ligand, which accelerates the nickel-catalyzed monosubstitution of a polyfluoroarene with an organozinc reagent, revealed that the alkoxy group and the diphosphine act independently to facilitate cooperation of a Lewis acid and a transition metal.
Collateral Crises
Authors: Gorton Gary , Ordoñez Guillermo
Published: February 2014

Short-term collateralized debt, private money, is efficient if agents are willing to lend without producing costly information about the collateral backing the debt. When the economy relies on such informationally insensitive debt, firms with low quality collateral can borrow, generating a credit boom and an increase in output. Financial fragility is endogenous; it builds up over time as information about counterparties decays. A crisis occurs when a ( possibly small) shock causes agents to suddenly have incentives to produce information, leading to a decline in output. A social planner would produce more information than private agents but would not always want to eliminate fragility. (JEL D83, E23, E32, E44, G01)
A Macroeconomic Model with a Financial Sector
Authors: Brunnermeier Markus K. , Sannikov Yuliy
Published: February 2014

This article studies the full equilibrium dynamics of an economy with ﬁnancial frictions. Due to highly nonlinear ampliﬁcation effects, the economy is prone to instability and occasionally enters volatile crisis episodes. Endogenous risk, driven by asset illiquidity, persists in crisis even for very low levels of exogenous risk. This phenomenon, which we call the volatility paradox, resolves the Kocherlakota ( 2000) critique. Endogenous leverage determines the distance to crisis. Securitization and derivatives contracts that improve risk sharing may lead to higher leverage and more frequent crises. (JEL E13, E32, E44, E52, G01, G12, G20)
Finance and Misallocation: Evidence from Plant-Level Data
Authors: Midrigan Virgiliu , Xu Daniel Yi
Published: February 2014

We use producer-level data to evaluate the role of financial frictions in determining total factor productivity (TFP). We study a model of establishment dynamics in which financial frictions reduce TFP through two channels. First, finance frictions distort entry and technology adoption decisions. Second, finance frictions generate dispersion in the returns to capital across existing producers and thus productivity losses from misallocation. Parameterizations of our model consistent with the data imply fairly small losses from misallocation, but potentially sizable losses from inefficiently low levels of entry and technology adoption. (JEL E32, E44, F41, G32, L60, O33, O47)
Tracing Value-Added and Double Counting in Gross Exports
Authors: Koopman Robert , Wang Zhi , Wei Shang-Jin
Published: February 2014

This paper proposes an accounting framework that breaks up a country’s gross exports into various value-added components by source and additional double-counted terms. Our parsimonious framework bridges a gap between official trade statistics (in gross value terms) and national accounts (in value-added terms), and integrates all previous measures of vertical specialization and value-added trade in the literature into a unified framework. To illustrate the potential of such a method, we present a number of applications including re-computing revealed comparative advantages and the magnifying impact of multi-stage production on trade costs. (JEL E01, E16, F14, F23, L14)
Market Size, Competition, and the Product Mix of Exporters
Authors: Mayer Thierry , Melitz Marc J. , Ottaviano Gianmarco I. P.
Published: February 2014

We build a theoretical model of multi-product firms that highlights how competition across market destinations affects both a firm’s exported product range and product mix. We show how tougher competition in an export market induces a firm to skew its export sales toward its best performing products. We find very strong confirmation of this competitive effect for French exporters across export market destinations. Theoretically, this within-firm change in product mix driven by the trading environment has important repercussions on firm productivity. A calibrated fit to our theoretical model reveals that these productivity effects are potentially quite large. (JEL D21, D24, F13, F14, F41, L11)
Do Consumers Respond to Marginal or Average Price? Evidence from Nonlinear Electricity Pricing
Authors: Ito Koichiro
Published: February 2014

Nonlinear pricing and taxation complicate economic decisions by creating multiple marginal prices for the same good. This paper provides a framework to uncover consumers’ perceived price of nonlinear price schedules. I exploit price variation at spatial discontinuities in electricity service areas, where households in the same city experience substantially different nonlinear pricing. Using household-level panel data from administrative records, I find strong evidence that consumers respond to average price rather than marginal or expected marginal price. This suboptimizing behavior makes nonlinear pricing unsuccessful in achieving its policy goal of energy conservation and critically changes the welfare implications of nonlinear pricing. (JEL D12, L11, L94, L98, Q41)
Time to Build and Fluctuations in Bulk Shipping
Authors: Kalouptsidi Myrto
Published: February 2014

This paper explores the nature of fluctuations in world bulk shipping by quantifying the impact of time to build and demand uncertainty on investment and prices. We examine the impact of both construction lags and their lengthening in periods of high investment activity, by constructing a dynamic model of ship entry and exit. A rich dataset of secondhand ship sales allows for a new estimation strategy: resale prices provide direct information on value functions and allow their nonparametric estimation. We find that moving from time-varying to constant to no time to build reduces prices, while significantly increasing both the level and volatility of investment. (JEL G31, L11, L62, L92)
Time Allocation and Task Juggling
Authors: Coviello Decio , Ichino Andrea , Persico Nicola
Published: February 2014

A single worker allocates her time among different projects which are progressively assigned. When the worker works on too many projects at the same time, the output rate decreases and completion time increases according to a law which we derive. We call this phenomenon “task juggling” and argue that it is pervasive in the workplace. We show that task juggling is a strategic substitute of worker effort. We then present a model where task juggling is the result of lobbying by clients, or coworkers, each seeking to get the worker to apply effort to his project ahead of the others’. (JEL J22, M12, M54)
How Financial Incentives Induce Disability Insurance Recipients to Return to Work
Authors: Kostøl Andreas Ravndal , Mogstad Magne
Published: February 2014

Using a local randomized experiment that arises from a sharp discontinuity in Disability Insurance (DI) policy in Norway, we provide transparent and credible identification of how financial incentives induce DI recipients to return to work. We find that many DI recipients have considerable capacity to work that can be effectively induced by providing financial work incentives. We further show that providing work incentives to DI recipients may both increase their disposable income and reduce program costs. Our findings also suggest that targeted policies may be the most effective in encouraging DI recipients to return to work. (JEL D14, H55, J14, J22, J28)
Income and Democracy: Comment
Authors: Cervellati Matteo , Jung Florian , Sunde Uwe , Vischer Thomas
Published: February 2014

Acemoglu et al. (2008) document that the correlation between income per capita and democracy disappears when including time and country fixed effects. While their results are robust for the full sample, we find evidence for significant but heterogeneous effects of income on democracy: negative for former colonies, but positive for non-colonies. Within the sample of colonies we detect heterogeneous effects related to colonial history and early institutions. The zero mean effect estimated by Acemoglu et al. (2008) is consistent with effects of opposite signs in the different subsamples. Our findings are robust to the use of alternative data and estimation techniques. (JEL D72, O17, O47)
Economics of Free Under Perpetual Licensing: Implications for the Software Industry
Authors: Niculescu Marius F. , Wu D. J.
Published: February 2014

In this paper, we explore the economics of free under perpetual licensing. In particular, we focus on two emerging software business models that involve a free component: feature-limited freemium (FLF) and uniform seeding (S). Under FLF, the firm offers the basic software version for free, while charging for premium features. Under S, the firm gives away for free the full product to a percentage of the addressable market uniformly across consumer types. We benchmark their performance against a conventional business model under which software is sold as a bundle (labeled as “charge for everything” or CE) without free offers. In the context of consumer bounded rationality and information asymmetry, we develop a unified two-period consumer valuation learning framework that accounts for both word-of-mouth (WOM) effects and experience-based learning, and use it to compare and contrast the three business models. Under both constant and dynamic pricing, for moderate strength of WOM signals, we derive the equilibria for each model and identify optimality regions. In particular, S is optimal when consumers significantly underestimate the value of functionality and cross-module synergies are weak. When either cross-module synergies are stronger or initial priors are higher, the firm decides between CE and FLF. Furthermore, we identify nontrivial switching dynamics from one optimality region to another depending on the initial consumer beliefs about the value of the embedded functionality. For example, there are regions where, ceteris paribus, FLF is optimal when the prior on premium functionality is either relatively low or high, but not in between. We also demonstrate the robustness of our findings with respect to various parameterizations of cross-module synergies, strength of WOM effects, and number of periods. We find that stronger WOM effects or more periods lead to an expansion of the seeding optimality region in parallel with a decrease in the seeding ratio. Moreover, under CE and dynamic pricing, second period price may be decreasing in the initial consumer valuation beliefs when WOM effects are strong and the prior is relatively low. However, this is not the case under weak WOM effects. We also discuss regions where price skimming and penetration pricing are optimal. Our results provide key managerial insights that are useful to firms in their business model search and implementation.
Stable fixation of the IBP humeral component implanted without cement in total elbow replacement
Authors: deVos M. J. , Verdonschot N. , Luites J. W. H. , Anderson P. G. , Eygendaal D.
Published: February 2014

We determined the short-term clinical outcome and migration within the bone of the humeral cementless component of the Instrumented Bone Preserving (IBP) total elbow replacement in a series of 16 patients. There were four men and 12 women with a mean age at operation of 63 years (40 to 81). Migration was calculated using radiostereometric analysis. There were no intra-operative complications and no revisions. At two-year follow-up, all patients showed a significant reduction in pain and functional improvement of the elbow (both p < 0.001). Although ten components (63%) showed movement or micromovement during the first six weeks, 14 (88%) were stable at one year post-operatively. Translation was primarily found in the proximal direction (median 0.3 mm (interquartile range (IQR) -0.09 to 0.8); the major rotational movement was an anterior tilt (median 0.7° (IQR 0.4° to 1.6°)). One malaligned component continued to migrate during the second year, and one component could not be followed beyond three months because migration had caused the markers to break off the prosthesis.

This study shows promising early results for the cementless humeral component of the IBP total elbow replacement. All patients had a good clinical outcome, and most components stabilised within six months of the operation.

Cite this article: Bone Joint J 2014;96-B:229–36.
Arthroscopic debridement in the treatment of patients with osteoarthritis of the elbow, based on computer simulation
Authors: Miyake J. , Shimada K. , Oka K. , Tanaka H. , Sugamoto K. , Yoshikawa H. , Murase T.
Published: February 2014

We retrospectively assessed the value of identifying impinging osteophytes using dynamic computer simulation of CT scans of the elbow in assisting their arthroscopic removal in patients with osteoarthritis of the elbow. A total of 20 patients were treated (19 men and one woman, mean age 38 years (19 to 55)) and followed for a mean of 25 months (24 to 29). We located the impinging osteophytes dynamically using computerised three-dimensional models of the elbow based on CT data in three positions of flexion of the elbow. These were then removed arthroscopically and a capsular release was performed.

The mean loss of extension improved from 23° (10° to 45°) pre-operatively to 9° (0° to 25°) post-operatively, and the mean flexion improved from 121° (80° to 140°) pre-operatively to 130° (110° to 145°) post-operatively. The mean Mayo Elbow Performance Score improved from 62 (30 to 85) to 95 (70 to 100) post-operatively. All patients had pain in the elbow pre-operatively which disappeared or decreased post-operatively. According to their Mayo scores, 14 patients had an excellent clinical outcome and six a good outcome; 15 were very satisfied and five were satisfied with their post-operative outcome.

We recommend this technique in the surgical management of patients with osteoarthritis of the elbow.

Cite this article: Bone Joint J 2014;96-B:237–41.
Effects of psychological distress and perceptions of illness on recovery from total knee replacement
Authors: Hanusch B. C. , O’Connor D. B. , Ions P. , Scott A. , Gregg P. J.
Published: February 2014

This cohort study investigated the influence of psychological factors, including perception of illness, anxiety and depression on recovery and functional outcome after total knee replacement surgery.

A total of 100 patients (55 male; 45 female) with a mean age of 71 (42 to 92) who underwent a primary total knee replacement for osteoarthritis were recruited into this study. In all 97 participants completed the six week and 87 the one year follow-up questionnaires.

Pre-operatively patients completed the revised Illness Perception Questionnaire, Hospital Anxiety and Depression Scale and Recovery Locus of Control Scale. Function was assessed pre-operatively, at six weeks and one year using Oxford Knee Score (OKS) and the goniometer-measured range of movement (ROM).

The results showed that pre-operative function had the biggest impact on post-operative outcome for ROM and OKS. In addition questionnaire variables and depression had an impact on the OKS at six weeks. Depression and anxiety were also associated with a higher (worse) knee score at one year but did not influence the ROM at either six weeks or one year.

Recovery from total knee replacement can be difficult to predict. This study has identified psychological factors that play an important role in recovery from surgery and functional outcome. These should be taken into account when considering patients for total knee replacement.

Cite this article: Bone Joint J 2014;96-B:210–16.
Lack of fifth anchoring point and violation of the insertion of the rotator cuff during antegrade humeral nailing
Authors: Euler S. A. , Hengg C. , Kolp D. , Wambacher M. , Kralinger F.
Published: February 2014

Antegrade nailing of proximal humeral fractures using a straight nail can damage the bony insertion of the supraspinatus tendon and may lead to varus failure of the construct. In order to establish the ideal anatomical landmarks for insertion of the nail and their clinical relevance we analysed CT scans of bilateral proximal humeri in 200 patients (mean age 45.1 years (sd 19.6; 18 to 97) without humeral fractures. The entry point of the nail was defined by the point of intersection of the anteroposterior and lateral vertical axes with the cortex of the humeral head. The critical point was defined as the intersection of the sagittal axis with the medial limit of the insertion of the supraspinatus tendon on the greater tuberosity. The region of interest, i.e. the biggest entry hole that would not encroach on the insertion of the supraspinatus tendon, was calculated setting a 3 mm minimal distance from the critical point. This identified that 38.5% of the humeral heads were categorised as ‘critical types’, due to morphology in which the predicted offset of the entry point would encroach on the insertion of the supraspinatus tendon that may damage the tendon and reduce the stability of fixation.

We therefore emphasise the need for ‘fastidious’ pre-operative planning to minimise this risk.

Cite this article: Bone Joint J 2014;96-B:249–53.
Disability following combat-sustained nerve injury of the upper limb
Authors: Rivera J. C. , Glebus G. P. , Cho M. S.
Published: February 2014

Injuries to the limb are the most frequent cause of permanent disability following combat wounds. We reviewed the medical records of 450 soldiers to determine the type of upper limb nerve injuries sustained, the rate of remaining motor and sensory deficits at final follow-up, and the type of Army disability ratings granted. Of 189 soldiers with an injury of the upper limb, 70 had nerve-related trauma. There were 62 men and eight women with a mean age of 25 years (18 to 49). Disabilities due to nerve injuries were associated with loss of function, neuropathic pain or both. The mean nerve-related disability was 26% (0% to 70%), accounting for over one-half of this cohort’s cumulative disability. Patients injured in an explosion had higher disability ratings than those injured by gunshot. The ulnar nerve was most commonly injured, but most disability was associated with radial nerve trauma. In terms of the final outcome, at military discharge 59 subjects (84%) experienced persistent weakness, 48 (69%) had a persistent sensory deficit and 17 (24%) experienced chronic pain from scar-related or neuropathic pain. Nerve injury was the cause of frequent and substantial disability in our cohort of wounded soldiers.

Cite this article: Bone Joint J 2014;96-B:254–8.
The challenge of pelvic discontinuity
Authors: Abolghasemian M. , Tangsaraporn S. , Drexler M. , Barbuto R. , Backstein D. , Safir O. , Kuzyk P. , Gross A.
Published: February 2014

The use of ilioischial cage reconstruction for pelvic discontinuity has been replaced by the Trabecular Metal (Zimmer, Warsaw, Indiana) cup-cage technique in our institution, due to the unsatisfactory outcome of using a cage alone in this situation. We report the outcome of 26 pelvic discontinuities in 24 patients (20 women and four men, mean age 65 years (44 to 84)) treated by the cup-cage technique at a mean follow-up of 82 months (12 to 113) and compared them with a series of 19 pelvic discontinuities in 19 patients (18 women and one man, mean age 70 years (42 to 86)) treated with a cage at a mean follow-up of 69 months (1 to 170). The clinical and radiological outcomes as well as the survivorship of the groups were compared. In all, four of the cup-cage group (15%) and 13 (68%) of the cage group failed due to septic or aseptic loosening. The seven-year survivorship was 87.2% (95% confidence interval (CI) 71 to 103) for the cup-cage group and 49.9% (95% CI 15 to 84) for the cage-alone group (p = 0.009). There were four major complications in the cup-cage group and nine in the cage group. Radiological union of the discontinuity was found in all successful cases in the cup-cage group and three of the successful cage cases. Three hips in the cup-cage group developed early radiological migration of the components, which stabilised with a successful outcome.

Cup-cage reconstruction is a reliable technique for treating pelvic discontinuity in mid-term follow-up and is preferred to ilioischial cage reconstruction. If the continuity of the bone graft at the discontinuity site is not disrupted, early migration of the components does not necessarily result in failure.

Cite this article: Bone Joint J 2014;96-B:195–200.