bluuebunny/crossref_metadata_2025 huggingface dataset:
Usefulness of the 6-minute walk test and the 200-metre fast walk test to individualize high intensity interval and continuous exercise training in coronary artery disease patients after acute coronary syndrome: a pilot controlled clinical study
Authors: Gremeaux M , Hannequin A , Laurent Y , Laroche D , Casillas JM , Gremeaux V
Published: July 2011

Objective: To study the effects of three individualized exercise training prescriptions using either a percentage of maximal heart rate (HR), maximal 6-minute walk test (6MWT) HR, or maximal 200-metre fast walk test (200-mFWT) HR, on walking performance and exercise capacity in coronary artery disease (CAD) patients.

Design: Controlled clinical study.

Participants: Twenty-seven outpatients enrolled in a rehabilitation programme after an acute coronary syndrome.

Setting: Cardiac rehabilitation unit.

Interventions: Three groups: (A): moderate intensity continuous exercise (MICE) at 70% of the maximal HR of the graded maximal exercise test ( n = 10); (B): MICE at the maximal 6MWT HR ( n = 8); (C): high intensity interval training (HIIT) based on the 6MWT and the 200-mFWT maximal HR ( n = 9). Group B and C performed walk tests every 2 weeks, to readjust training HR (THR) if needed.

Measures: 6MWT and 200-mFWT performances, peak VO2 and peak power (Pmax).

Results: 6MWT and 200-mFWT performances improved significantly and similarly in all groups ( P < 0.05). Peak VO2 improved significantly in all groups ( P < 0.05), this improvement being higher in group C (HIIT) versus A ( P < 0.05). Group B was closer to the recommended THR during exercise sessions compared to group A.

Conclusion: This pilot study showed that using the 6MWT and 200-mFWT HR to individualize MICE or HIIT prescription is feasible in CAD patients, and could lead them closer to THR objective, to similar improvements in walking performance, and greater peak VO2 increase for HIIT. Future randomised studies should investigate long-term effects of programmes prescribed from walk tests HR, especially for HIIT modality.
Sociospatial inequalities in health-related behaviours
Authors: Pearce Jamie , Barnett Ross , Moon Graham
Published: July 2011

There has been a resurgence of interest in how the social, built and cultural environments contribute to shaping health outcomes. The pathways relating place to health behaviour have received less attention. We develop a nuanced understanding of the pathways linking individuals, places and smoking. Two key pathways operate: place-based ‘practices’ and place-based ‘regulation’. Future geographical research should pay attention to the different scale effects, encompass a wider set of influences which affect the liveability and social composition of neighbourhoods, and specify group differences in the impact of the local economic and social environment upon smoking.
Male Team Sport Hazing Initiations in a Culture of Decreasing Homohysteria
Authors: Anderson Eric , McCormack Mark , Lee Harry
Published: July 2011

In this longitudinal ethnographic research, we report on 7 years of hazing rituals on two separate men’s sports teams at one university in the United Kingdom. Using 38 in-depth interviews alongside naturalistic observations of the initiation rituals, we demonstrate that hazing activities have changed from being centered around homophobic same-sex activities to focusing on extreme levels of alcohol consumption. We show that whereas same-sex activities once occurred paradoxically to prohibit them, today these initiations open up the possibility of same-sex behaviors for young men in the life stage of emergent adulthood.
Inability, culpability and affected ignorance: reflections on Michele Moody-Adams
Authors: Peacock Mark
Published: July 2011

In this article, I examine Michele Moody-Adams’ critique of the ‘inability thesis’, according to which some cultures make the resources for criticizing injustice ‘unavailable’ to their members. I investigate Moody-Adams’ alternative ‘affected ignorance’ thesis. Using the example of slavery in ancient Greece, I consider two potential candidates for affected ignorance which involve, respectively, ‘unawareness’ and ‘mistaken moral weighing’; in neither, I hold, may one ascribe culpability to those involved.
Psychological life as enterprise: social practice and the government of neo-liberal interiority
Authors: Binkley Sam
Published: July 2011

This article theorizes the contemporary government of psychological life as neo-liberal enterprise. By drawing on Foucauldian critical social theory, it argues that the constellations of power identified with the psy-function and neo-liberal governmentality can be read through the problematic of everyday practice. On a theoretical level, this involves a re-examination of the notion of dispositif, to uncover the dynamic, ambivalent and temporal practices by which subjectification takes place. Empirically, this point is illustrated through a reflection of one case of neo-liberal psychological life: life coaching.
Stiffness and strength aspects in the design of automotive coil springs for McPherson front suspensions: a case study
Authors: Bartolozzi R , Frendo F
Published: July 2011

The current paper deals with the elastic and stress analysis of a side-load spring, which is employed in cars belonging to the medium segment of the European automotive market. In the design of this kind of spring both the elastic characteristics and the fatigue strength have to be considered as significant aspects. Side-load springs, indeed, have a thrust axis which results in skew with respect to the damper axis; for this reason they are widely employed in front McPherson automotive suspensions in order to minimize the side force acting on the strut damper, which is responsible for the undesired damper-sticking phenomenon. In addition to this particular elastic property, as a consequence of the research effort in reducing the mass of components typical of the automotive industry, these springs have to face very high working stresses. The structural reliability of the spring must therefore be ensured by high residual stresses, which are induced by presetting and shot peening treatment at the end of the manufacturing process.

The evolution of the thrust axis during suspension travel was analysed by a finite element (FE) model of the spring–seats assembly, built starting from a three-dimensional (3D) scan of the spring. In addition an experimental campaign was planned in order to measure the residual stresses at several points along the spring by X-ray diffraction. The actual stresses were then obtained as the superposition of those produced by the external loads, computed by means of the FE model, and the measured residual stresses. The beneficial effect of residual stresses on the structural reliability is discussed with a theoretical fatigue analysis on the basis of different multiaxial criteria. A mechanism of residual stress generation, based on the superposition of stresses coming from presetting and shot peening, is also suggested with the aid of FE simulations.
Modelling of passive ammonia selective catalytic reduction system for lean-burn spark ignition direct injection engines
Authors: Narayanaswamy K , Najt P M , Li W , Perry K L , Kim C H
Published: July 2011

Lean-burn spark ignition direct injection (SIDI) engines offer potential fuel economy savings; however, the lack of simple and cost-effective lean nitrogen oxide (NO x) aftertreatment systems hinder their broad application. Lean NO x traps (LNT) and urea selective catalytic reduction (SCR) catalysts have been widely investigated as possible lean gasoline aftertreatment technologies, but with limited acceptance.

Passive ammonia SCR operation is a promising low-cost alternative for lean NO x aftertreatment with SIDI engines. The aftertreatment system includes close-coupled three-way catalyst (TWC) converters and one or more under-floor SCR catalysts. Ammonia (NH3) is formed on the TWC with short pulses of rich engine operations and the generated NH3 is then stored on the under-floor SCR catalysts. During subsequent lean operations, the NO x that breaks through the TWC converters is reduced to nitrogen by NH3 stored on the SCR catalysts.

This paper provides an overview of system level analysis as a complement to experimental testing in the development of a passive NH3 SCR-based aftertreatment system. Various aftertreatment architectures (SCR type, the order, and location of the catalysts) were efficiently evaluated and screened, to achieve the best trade-off between engine back-pressure, catalyst warm-up, emission constraints, and acceptable thermal ageing under high-speed/load conditions.
A multi-zone combustion model with detailed chemistry including cycle-to-cycle dynamics for diesel engine control design
Authors: Jochim B , Felsch C , Drews P , Vanegas A , Hoffmann K , Abel D , Peters N , Pitsch H
Published: July 2011

This paper reviews the research activities within the subproject B1 Model Reduction for Low-Temperature Combustion Processes through CFD-Simulations and Multi-Zone Models of the Collaborative Research Centre SFB 686 – Model-Based Control of Homogenized Low-Temperature Combustion. The SFB 686 is carried out at RWTH Aachen University, Germany and Bielefeld University, Germany, and is funded by the German Research Foundation (DFG). This paper thereby summarizes the outcome of various publications by the authors, with the appropriate references given in the individual sections. Additionally, some new results are introduced.

The particular subject of this work is a dynamic simulation strategy for premixed charge compression ignition (PCCI) combustion that can be used in closed-loop control development. A detailed multi-zone chemistry model for the high-pressure part of the engine cycle is extended by a mean value gas exchange model accounting for the low-pressure part. Thus, an efficient model capable of describing PCCI combustion is sufficiently well established. In order to capture cycle-to-cycle dynamics, identified system dynamics influencing the input parameters are incorporated. For this, a Wiener model is set up that uses the combustion model as a nonlinear system representation. In this way, a dynamic nonlinear model for the representation of the controlled plant Diesel engine is created. The model is validated against transient experimental engine data.
The effect of a low ambient temperature on the cold-start emissions and fuel consumption of passenger cars
Authors: Bielaczyc P , Szczotka A , Woodburn J
Published: July 2011

This paper examines the cold-start-up events of spark and compression ignition engines in the context of transient operation and emissions control. When the temperatures of the oil, coolant and engine block are equal or close to the ambient temperature, start-up can be difficult to achieve without significant excess levels of exhaust emissions and fuel consumption. In general, the lower the ambient temperature, the more significant these problems are. The physical processes responsible for this phenomenon are briefly discussed. Excess emission factors from a pool of Euro 4 and Euro 5 petrol vehicles and three Euro 5 diesel vehicles are presented, as tested over the Urban Drive Cycle at 24 °C and at −7 °C. A full modal emissions analysis was also conducted at 24 °C and at −7 °C on one petrol vehicle and one diesel vehicle over the New European Drive Cycle. The most problematic emissions are identified for both engine types, and recommendations are made to legislators regarding cold-start emissions.
Factors Associated With Successful Resuscitation of Out-of-Hospital Cardiac Arrest at Rajavithi Hospital’s Narenthorn Emergency Medical Service Center, Thailand
Authors: Yeeheng Ubon
Published: July 2011

The objective of this study is to determine factors associated with successful resuscitation of out-of-hospital cardiac arrest (OHCA) patients by Narenthorn Emergency Medical Service Center (EMS), Thailand. A retrospective observational study was conducted with 73 OHCA patients who were resuscitated from December 2004 to January 2007. Inferential statistics, univariate (χ2) and multivariate analyses (logistic regression) were applied for data analysis. A total of 73 OHCA patients were included. The mean age was 58.3 years; 86.3% were ≥40 years, 72.6% were male. The causes of arrest were cardiac problem 53.4%. In all, 46.6% were witnessed arrest; 53.4% had response time (RT) ≥10 minutes, and 27.4% had bystander cardiopulmonary resuscitation (CPR). Overall, 79.5% were found in the residence. Initial electrocardiogram showed that 74% were nonshockable rhythm. A total of 34.2% were resuscitated by an EMS team with <4 members, and 53.4% had return of spontaneous circulation, survival to admission was 61.5% and survival to discharge was 7.7%. Witnessed arrest (odds ratio [OR] = 7.403; 95% confidence interval [CI] = 2.169-24.683) and bystander CPR (OR = 5.619; 95% CI = 1.014-36.170) had correlation with successful resuscitation of OHCA patients. RT showed a trend toward statistical significance (OR = 1.051; 95% CI = 0.765-16.083). This study found that witnessed arrest and bystander CPR were major factors associated with successful resuscitation of OHCA patients. Our findings will be useful for the development of community programs to decrease the mortality from OHCA.
The Cost-Effectiveness of HIV Voluntary Counseling and Testing in China
Authors: Wang Shuhong , Moss John R. , Hiller Janet E.
Published: July 2011

China has experienced a dramatic increase in the number of HIV infections. To control the AIDS epidemic, free HIV voluntary counseling and testing has been made available in China. This study compared the cost-effectiveness of this program for 2 populations—the general population and men who have sex with men (MSM), to examine the value for money of this program. A Bernoulli-process model has been used to translate the changes in sexual behaviors to the number of HIV infections averted. Costs are estimated from a societal perspective. The outcomes are measured in terms of the incremental cost per HIV infection averted and the incremental cost per disability-adjusted life-year averted. The study found that the voluntary counseling and testing for the general population is not cost-effective based on the threshold adopted, whereas the same HIV prevention program for MSM is cost-saving. These results suggest that the efficiency of resources used could be substantially improved by appropriately targeting high-risk population groups. Therefore measures should be taken to increase the uptake of this intervention among high-risk groups.
Finite Element Analysis of Damage in Ductile Structures Using a Nonlocal Model Combined with a Three-field Formulation
Authors: Feld-Payet S. , Besson J. , Feyel F.
Published: July 2011

Solving finite element problems involving elasto-plasticity coupled with damage softening faces two major difficulties: mesh dependence and volumetric locking. In this study, a specific finite element is proposed which allows to solve simultaneously both problems within the small strain framework. It combines a mixed treatment based on a three-field formulation (displacements, assumed pressure, and assumed dilatation) to solve the volumetric locking and a nonlocal implicit gradient-enhanced formulation to avoid localization of damage. Simulations on a double-notched specimen are presented which allow to compare the nonlocal formulation and the mixed nonlocal formulation. Triangular elements with quadratic shape functions for the displacements and linear shape functions for the assumed dilatation, assumed pressure, and nonlocal variable are used. First results show that the mixed nonlocal method regularizes the problem and allows to obtain smoother stress fields than the nonlocal method at the same time.
The Cumulative Impact of Sexual Revictimization on Emotion Regulation Difficulties
Authors: Walsh Kate , DiLillo David , Scalora Mario J.
Published: July 2011

The present study examined associations between child sexual abuse (CSA), adult sexual victimization, and emotion regulation difficulties in a sample of 168 incarcerated women. Approximately 50% of the participants reported CSA, 54% reported adult sexual victimization, and 38% reported sexual revictimization (i.e., CSA and adult victimization). Revictimized women reported significantly greater difficulties with several facets of emotion regulation when compared to singly victimized and nonvictimized women. Interestingly, singly victimized women did not demonstrate greater emotion regulation deficits when compared to nonvictims. Findings suggest that the negative impact of victimization experiences on adult emotion regulation abilities may be cumulative. Furthermore, they highlight the potential importance of assessing and targeting emotion regulation difficulties among child abuse and adult sexual victimization survivors.
Effect of Al/Ti ratio on the mechanical properties and tribological behaviours of TiAlN coatings deposited by multi-arc ion plating method
Authors: Zhang J , Gu Y
Published: July 2011

This article presents a systematic study of the effect of Al/Ti ratio of the TiAlN coatings deposited on high-speed steel W18Cr4V substrates on the mechanical properties and tribological behaviours. Three different Al/Ti-ratio TiAlN coatings, with the targets of Ti60Al40, Ti50Al50, and Ti25Al75, were prepared using the multi-arc ion plating deposition method. X-ray diffraction analyses revealed that all three coatings exhibited a face-centred cubic crystal structure. AES analyses showed that the chemical compositions of the coatings were different from those of the targets, and the Al/Ti ratios were changed during the deposition. Mechanical and wear tests showed that the Al/Ti ratio had a profound effect on the strength and tribological properties of the coatings. Using nano-indentation techniques, the measured nano-hardnesses and Young’s moduli increased with increasing the Al/Ti ratio. Scratch tests showed that lower Al/Ti ratio improved the adhesion strengths of the coatings. Wear tests proved that the coefficients of friction were reduced by increasing the Al/Ti ratio. Moreover, two different balls, steel, and ceramics, were separately tested on the TiAlN-coated steel discs using a conventional dry ball-on-disc sliding wear apparatus. Both friction coefficient curves and micro-graphs revealed distinctly different wear mechanisms. It was found that the adhesive wear behaviour was dominant between the TiAlN coating layers and steel, while the abrasive and fatigue wear behaviour prevailed in the case of the ceramic ball. The evolutions of the coating micro-structures during the wear tests were examined by scanning electron microscope. All experimental results suggested that highest Al content, Ti14.8Al85.2N coating, had the best combined mechanical and tribological properties.
A new fuzzy evidential reasoning method for risk analysis and control of a liquefied natural gas carrier system
Authors: Nwaoha T C , Yang Z , Wang J , Bonsall S
Published: July 2011

In this research, the safety/risk level of a liquefied natural gas (LNG) carrier system is investigated through the application of a fuzzy evidential reasoning (FER) method to uncertainty treatment of its failure modes. A fuzzy set manipulation formula with multiple parameters such as consequence severity, failure consequence probability, and failure likelihood is used to assess the safety/risk levels of failure modes of the system. Such failure estimations are synthesized to evaluate the whole system’s safety/risk level using an evidential reasoning (ER) approach. Risk control options (RCOs) are developed for reduction/control of high-risk level of the system. The best RCO, which is the one with the highest preference degree, is used to improve the safety level of the system.
Modeling and simulation of a small-sized Tiltrotor UAV
Authors: Çakıcı Ferit , Leblebicioğlu M. Kemal
Published: July 2011

Unmanned aerial vehicles (UAVs) are remotely piloted or self-piloted aircrafts that can carry cameras, sensors, communication equipment and other payloads. Tiltrotor UAVs provide a unique platform that fulfills the needs for ever-changing mission requirements, by combining the desired features of hovering like a helicopter and reaching high forward speeds like an airplane, which might be a force multiplier in the battlefield. In this paper, the conceptual design and aerodynamical model of a realizable small-sized Tiltrotor UAV are presented, and the linearized state-space models are obtained around the trim points for airplane, helicopter and conversion modes. Controllers are designed using tracking optimal control method and gain scheduling is employed to obtain a simulation for the whole flight envelope. An interactive software infrastructure is established for the design, analysis and simulation phases, based on the theoretical concepts.
How to use marginal structural models in randomized trials to estimate the natural direct and indirect effects of therapies mediated by causal intermediates
Authors: Oba Koji , Sato Tosiya , Ogihara Toshio , Saruta Takao , Nakao Kazuwa
Published: July 2011

Background Although intention-to-treat analysis is a standard approach, additional supplemental analyses are often required to evaluate the biological relationship among interventions, intermediates, and outcomes. Therefore, we need to evaluate whether the effect of an intervention on a particular outcome is mediated by a hypothesized intermediate variable.

Purpose To evaluate the size of the direct effect in the total effect, we applied the marginal structural model to estimate the average natural direct and indirect effects in a large-scale randomized controlled trial (RCT).

Method The average natural direct effect is defined as the difference in the probability of a counterfactual outcome between the experimental and control arms, with the intermediate set to what it would have been, had the intervention been a control treatment. We considered two marginal structural models to estimate the average natural direct and indirect effects introduced by VanderWeele ( Epidemiology 2009) and applied them in a large-scale RCT – the Candesartan Antihypertensive Survival Evaluation in Japan (CASE-J trial) – that compared angiotensin receptor blockers and calcium-channel blockers in high-risk hypertensive patients.

Results There were no strong blood pressure-independent or dependent effects; however, a systolic blood pressure reduction of about 1.9 mmHg suppressed all events. Compared to the blood pressure-independent effects of calcium channel blockers, those of angiotensin receptor blockers contributed positively to cardiovascular and cardiac events, but negatively to cerebrovascular events.

Limitations There is a particular condition for estimating the average natural direct effect. It is impossible to check whether this condition is satisfied with the available data.

Conclusion We estimated the average natural direct and indirect effects through the achieved systolic blood pressure in the CASE-J trial. This first application of estimating the average natural effects in an RCT can be useful for obtaining an in-depth understanding of the results and further development of similar interventions.
Therapeutic potential of melatonin and its analogs in Parkinson’s disease: focus on sleep and neuroprotection
Authors: Srinivasan Venkatramanujam , Cardinali Daniel P. , Srinivasan Uddanapalli S. , Kaur Charanjit , Brown Gregory M. , Spence D. Warren , Hardeland Rüdiger , Pandi-Perumal Seithikurippu R.
Published: July 2011

Sleep disorders constitute major nonmotor features of Parkinson’s disease (PD) that have a substantial effect on patients’ quality of life and can be related to the progression of the neurodegenerative disease. They can also serve as preclinical markers for PD, as it is the case for rapid eye movement (REM)-associated sleep behavior disorder (RBD). Although the etiology of sleep disorders in PD remains undefined, the assessment of the components of the circadian system, including melatonin secretion, could give therapeutically valuable insight on their pathophysiopathology. Melatonin is a regulator of the sleep/wake cycle and also acts as an effective antioxidant and mitochondrial function protector. A reduction in the expression of melatonin MT1 and MT2 receptors has been documented in the substantia nigra of PD patients. The efficacy of melatonin for preventing neuronal cell death and for ameliorating PD symptoms has been demonstrated in animal models of PD employing neurotoxins. A small number of controlled trials indicate that melatonin is useful in treating disturbed sleep in PD, in particular RBD. Whether melatonin and the recently developed melatonergic agents (ramelteon, tasimelteon, agomelatine) have therapeutic potential in PD is also discussed.
Response of patients with refractory myasthenia gravis to rituximab: a retrospective study
Authors: Nowak Richard J. , DiCapua Daniel B. , Zebardast Nazlee , Goldstein Jonathan M.
Published: July 2011

Introduction: Myasthenia gravis, an autoimmune disorder of neuromuscular transmission, is treated by an array of immunomodulating therapies. A variable response is observed with certain patients being medically refractory. Methods: We report the results of 14 refractory generalized myasthenia gravis patients (6 AChR+; 8 MuSK+) treated with rituximab. Results: Sustained clinical improvement was observed in all patients as well as a reduction of conventional immunotherapies. Prednisone dose decreased a mean of 65.1%, 85.7%, and 93.8% after cycle 1, 2, and 3 of rituximab therapy, respectively. A statistically significant reduction in plasma exchange sessions was seen after cycle 1 with all patients being off of plasma exchange after cycle 3. Acetylcholine receptor antibody titers decreased a mean of 52.1% ( p = 0.0046) post-cycle 2. Conclusion: Our results support the hypothesis that rituximab is beneficial and well tolerated in managing refractory myasthenia gravis and nearly doubles published cases. We propose that B-cell-directed therapies may become an attractive option and suggest pursuit of a prospective trial.
A robust controller for non-linear MIMO systems using radial basis function neural network
Authors: Al-Duwaish H N , Rizvi S Z
Published: July 2011

This paper presents a controller design method for multi-input multi-output nonlinear systems using the artificial neural network. The designed controller uses radial basis function networks to generate optimal control signals abiding by constraints, if any, on the control signal, or on the system output. The salient features of the proposed controller include: no requirement of the explicit knowledge of the states of the system, no requirement of a priori knowledge of the non-linear model of the system, and ability of the controller to control time-varying systems or systems having non-minimum-phase characteristics. A recursive algorithm is developed to update the weights of the neural network. Non-linearities in the system as well as variations in system parameters are compensated by the neural network. Simulation results for non-linear systems are included at the end, and controller performance is analysed. A practical case study of single area non-linear automatic generation control is also considered to test the performance of the controller.
Protein functional links in Trypanosoma brucei, identified by gene fusion analysis
Authors: Dimitriadis Dimitris , Koumandou V Lila , Trimpalis Philip , Kossida Sophia
Published: July 2011

Background

Domain or gene fusion analysis is a bioinformatics method for detecting gene fusions in one organism by comparing its genome to that of other organisms. The occurrence of gene fusions suggests that the two original genes that participated in the fusion are functionally linked, i.e. their gene products interact either as part of a multi-subunit protein complex, or in a metabolic pathway. Gene fusion analysis has been used to identify protein functional links in prokaryotes as well as in eukaryotic model organisms, such as yeast and Drosophila.

Results

In this study we have extended this approach to include a number of recently sequenced protists, four of which are pathogenic, to identify fusion linked proteins in Trypanosoma brucei, the causative agent of African sleeping sickness. We have also examined the evolution of the gene fusion events identified, to determine whether they can be attributed to fusion or fission, by looking at the conservation of the fused genes and of the individual component genes across the major eukaryotic and prokaryotic lineages. We find relatively limited occurrence of gene fusions/fissions within the protist lineages examined. Our results point to two trypanosome-specific gene fissions, which have recently been experimentally confirmed, one fusion involving proteins involved in the same metabolic pathway, as well as two novel putative functional links between fusion-linked protein pairs.

Conclusions

This is the first study of protein functional links in T. brucei identified by gene fusion analysis. We have used strict thresholds and only discuss results which are highly likely to be genuine and which either have already been or can be experimentally verified. We discuss the possible impact of the identification of these novel putative protein-protein interactions, to the development of new trypanosome therapeutic drugs.
Neural correlates of cognitive impairment in
schizophrenia
Authors: Ortiz-Gil Jordi , Pomarol-Clotet Edith , Salvador Raymond , Canales-Rodríguez Erick J. , Sarró Salvador , Gomar Jesús J. , Guerrero Amalia , Sans-Sansa Bibiana , Capdevila Antoni , Junqué Carme , McKenna Peter J.
Published: July 2011

Background

Cognitive impairment is an established feature of schizophrenia. However,
little is known about its relationship to the structural and functional
brain abnormalities that characterise the disorder.

Aims

To identify structural and/or functional brain abnormalities associated
with schizophrenic cognitive impairment.

Method

We carried out structural magnetic resonance imaging (MRI) and
voxel-based morphometry in 26 participants who were cognitively impaired
and 23 who were cognitively preserved, all with schizophrenia, plus 39
matched controls. Nineteen of those who were cognitively impaired and 18
of those who were cognitively preserved plus 34 controls also underwent
functional MRI during performance of a working memory task.

Results

No differences were found between the participants who were cognitively
intact and those who were cognitively impaired in lateral ventricular
volume or whole brain volume. Voxel-based morphometry also failed to
reveal clusters of significant difference in grey and white matter volume
between these two groups. However, during performance of the n-back task,
the participants who were cognitively impaired showed hypoactivation
compared with those who were cognitively intact in the dorsolateral
prefrontal cortex among other brain regions.

Conclusions

Cognitive impairment in schizophrenia is not a function of the structural
brain abnormality that accompanies the disorder but has correlates in
altered brain function.
Marrying Up: The Role of Sex Ratio in Assortative Matching
Authors: Abramitzky Ran , Delavande Adeline , Vasconcelos Luis
Published: July 2011

We assemble a novel dataset to study the impact of male scarcity on marital assortative matching and other marriage market outcomes using the large shock that WWI caused to the number of French men. Using a difference-in-differences approach, we find that postwar in regions with higher mortality rates: men were less likely to marry women of lower social classes; men were more likely and women less likely to marry; out-of-wedlock births increased; divorce rates decreased; and the age gap decreased. These findings are consistent with men improving their position in the marriage market as they become scarcer. (JEL J12, J16, N34)
Financial Constraints and Inflated Home Prices during the Real Estate Boom
Authors: Ben-David Itzhak
Published: July 2011

During the housing boom, financially constrained home buyers artificially inflated transaction prices in order to draw larger mortgages. Using transaction data from Illinois that includes sellers' offers to inflate prices, I estimate that in 2005–2008, up to 16 percent of highly leveraged transactions had inflated prices of up to 9 percent. Inflated transactions were common in low-income neighborhoods and when intermediaries had a greater stake or an informational advantage. Borrowers who inflated prices were more likely to default, but their mortgage rates were not materially higher. Property prices in areas with a high rate of past price inflation exhibited momentum and high volatility. (JEL D14, E31, R31)
Education and Catch-up in the Industrial Revolution
Authors: Becker Sascha O , Hornung Erik , Woessmann Ludger
Published: July 2011

Research increasingly stresses the role of human capital in modern economic development. Existing historical evidence—mostly from British textile industries—however, rejects that formal education was important for the Industrial Revolution. Our new evidence from technological follower Prussia uses a unique school enrollment and factory employment database linking 334 counties from pre-industrial 1816 to two industrial phases in 1849 and 1882. Using pre-industrial education as instrument for later education and controlling extensively for pre-industrial development, we find that basic education is significantly associated with nontextile industrialization in both phases of the Industrial Revolution. Panel data models with county fixed effects confirm the results. (JEL I20, J24, N13, N33, N63)
The use of mathematical models to inform influenza pandemic preparedness and response
Authors: Wu Joseph T , Cowling Benjamin J
Published: July 2011

Influenza pandemics have occurred throughout history and were associated with substantial excess mortality and morbidity. Mathematical models of infectious diseases permit quantitative description of epidemic processes based on the underlying biological mechanisms. Mathematical models have been widely used in the past decade to aid pandemic planning by allowing detailed predictions of the speed of spread of an influenza pandemic and the likely effectiveness of alternative control strategies. During the initial waves of the 2009 influenza pandemic, mathematical models were used to track the spread of the virus, predict the time course of the pandemic and assess the likely impact of large-scale vaccination. While mathematical modeling has made substantial contributions to influenza pandemic preparedness, its use as a realtime tool for pandemic control is currently limited by the lack of essential surveillance information such as serological data. Mathematical modeling provided a useful framework for analyzing and interpreting surveillance data during the 2009 influenza pandemic, for highlighting limitations in existing pandemic surveillance systems, and for guiding how these systems should be strengthened in order to cope with future epidemics of influenza or other emerging infectious diseases.
Complete regression of early diffuse B-cell lymphoma in an HIV-positive patient on antiretroviral therapy alone
Authors: Katsidzira L , Ramsay A , Makunike-Mutasa R , Borok M
Published: July 2011

There is no evidence that antiretroviral therapy (ART) alone may result in complete remission of aggressive non-Hodgkin's lymphomas even though it improves the overall prognosis. We report a case in which early diffuse large B-cell lymphoma regressed completely after ART alone, raising the possibility that this may be sufficient therapy in selected cases.
Post-exposure prophylaxis following sexual exposure to HIV: a seven-year retrospective analysis in a regional centre
Authors: McCarty E J , Quah S , Maw R , Dinsmore W W , Emerson C R
Published: July 2011

An audit of 72 patients presenting for post-exposure prophylaxis following sexual exposure (PEPSE) to HIV (68 genitourinary medicine and 4 accident & emergency) was conducted from 2003 to 2009. The principal indications for PEPSE included 27 (38%) unprotected intercourse (15/27 vaginal and 12/27 anal) with a known HIV-positive partner, 20 (28%) unprotected receptive anal sex with male partner of unknown status, 17 (24%) following sexual assault and three (4%) unprotected sex with a partner from an endemic country. Of those who commenced PEPSE, 92% did so within the recommended 72 hours. Concurrent sexually transmitted infection (STI) was diagnosed in 8.3% patients (6.9% non-gonococcal urethritis and 1.4% rectal chlamydia). Fifty (69%) patients attended for follow-up and only 8% of these did not complete treatment. Twenty-five (35%) patients attended for repeat serology at three months and 18 (25%) at six months. All of the patients followed up remained HIV-negative.
Implanon® failure in an HIV-positive woman on antiretroviral therapy resulting in two ectopic pregnancies
Authors: McCarty E J , Keane H , Quinn K , Quah S
Published: July 2011

Since its introduction in 1999, Implanon® remains one of the preferred contraceptive choices for many women as it offers a highly effective means of long-term contraception for three years that does not rely on adherence. Like all hormonal contraceptives, certain hepatic enzyme-inducing drugs may reduce its efficacy. We present an interesting case of an HIV-positive woman on antiretroviral therapy having tubal pregnancies on two separate occasions with Implanon in place.
Using patient experience to measure the quality of HIV care
Authors: Land L , Hathorn E , Ross J D C
Published: July 2011

Measurement of health-care quality in the UK is no longer restricted to evaluating the effectiveness of treatments or the cost efficiency of services. There is a drive towards a patient-based agenda which enables them to make a clear contribution to the way services are shaped by expressing their values and sharing experiences. Positive engagement with HIV care has proven benefits to patients and the mandatory use of standardized reported outcome measures provides an opportunity to include HIV patients in the process of creating and refining an evaluation tool which places emphasis on aspects of care that are significant to them. Ultimately, this will provide services users with a stronger voice to guide appropriate service change and support the continuing improvement of HIV care.
Positive nucleic acid amplification tests for Neisseria gonorrhoeae in young people tested as part of the National Chlamydia Screening Programme
Authors: Skidmore S , Copley S , Cordwell D , Donaldson D , Ritchie D , Spraggon M
Published: July 2011

Little information is available on the prevalence of Neisseria gonorrhoeae (GC) infections outside genitourinary (GU) medicine clinics. A number of National Chlamydia Screening Programme areas now carry out simultaneous testing for Chlamydia trachomatis (CT) and GC in a single sample using nucleic acid amplification tests (NAATs). The aim of this study was to gather together data on dual testing from community settings. Information was collected from five programme areas. A total of 219,412 results were recorded with 18,370 CT positives, 1226 GC positives and among these 554 were with dual CT/GC infection. These figures highlight the fact that substantial numbers of positive GC NAAT results are found outside GU settings. An assessment of both the prevalence of GC and the proportion of extra cases that can be detected in all settings is needed, together with the implementation of robust plans to confirm, treat and manage these patients.
Abdominal lymphadenopathy in children with tuberculosis presenting with respiratory symptoms
Authors: Scheepers Shaun , Andronikou Savvas , Mapukata Ayanda , Donald Peter
Published: July 2011

Diagnosis of pulmonary tuberculosis (PTB) in children is challenging and radiographs are often normal or non-specific. Access to the chest using ultrasound is difficult, but access to the abdomen is simple and carries no radiation burden. Diagnosis of PTB using abdominal lymphadenopathy as a surrogate for mediastinal lymphadenopathy may present a simple and accurate additional diagnostic technique that is of value in developing countries. We determined the prevalence of abdominal lymphadenopathy in paediatric patients with confirmed TB presenting with respiratory symptoms. Chest radiographs and abdominal ultrasounds of 47 children with confirmed TB and respiratory symptoms were reviewed. The prevalence of abdominal TB was determined and comparisons made between thoracic and abdominal lymphadenopathy to determine the relative value of ultrasound. On ultrasound, the prevalence of abdominal lymphadenopathy was 19% and solid organ involvement was found in 23% of patients. Some 70% of children had thoracic lymphadenopathy on chest radiography, with 89% of patients having evidence of PTB. If chest radiography were to be considered the radiological reference standard, abdominal ultrasonography had a sensitivity of 18% (95% CI 7.0–35.5%) with a specificity of 79% (95% CI 49.2–95.1%) for thoracic lymphadenopathy. Ultrasound and chest radiography in combination detected a total of 36 patients with lymphadenopathy, with a 6% improvement in the rate of lymphadenopathy detection; however, this was not statistically significant. The prevalence of abdominal TB of 23% is noteworthy. We suggest that abdominal ultrasound has a definitive adjunctive role in investigating children with suspected TB.
New biomarkers for acute renal injury
Authors: Soni Sachin S. , Pophale Rupesh , Ronco Claudio
Published: July 2011

Incidence of acute kidney injury (AKI) is increasing rapidly to epidemic proportions. Development of AKI, especially in intensive care settings, is associated with increased morbidity, mortality and hospitalization costs. Currently available diagnostic tools are mostly insensitive for early diagnosis, however prompt diagnosis and risk stratification are necessary for guiding therapy and preventing progression of disease. Finding an early, reliable, suitable, easily reproducible, economical and accurate biomarker for AKI is a top research priority. In recent years, many urinary and serum proteins have been investigated as possible early markers of AKI and some of them have shown great promise. This topic reviews some of the emerging biomarkers of AKI.
Determination of local material properties of OSB sample by coupling advanced imaging techniques and morphology-based FEM simulation
Authors: Sebera Vaclav , Muszyński Lech
Published: July 2011

The goal was to determine local mechanical properties inside of oriented strand board (OSB) based on a realistic morphology-based finite element (FE) model and data acquired from a physical test performed on the same material. The spatial information and local grayscale intensity from CT-scans obtained from small OSB sample was transformed into a 2D regular morphology-based FE mesh with corresponding material properties. The model was then used to simulate the actual compression test performed on the specimen using simplified boundary conditions. The simulated strain fields from the model were compared with the actual strain field measured on the specimen surface during the compression test by means of a full-field optical method, named digital image correlation (DIC). Finally, the original set of material properties was adjusted by an iterative procedure to minimize the difference between the simulated and the measured strain data. The results show that the developed procedure is useful to find local material properties as well as for morphological modeling without the need of segmentation of the image data. The achieved results serve as a prerequisite for full 3D analyses of the complex materials.
Prolonged exposure to GH impairs insulin signaling in the heart
Authors: Miquet J G , Giani J F , Martinez C S , Muñoz M C , González L , Sotelo A I , Boparai R K , Masternak M M , Bartke A , Dominici F P , Turyn D
Published: July 2011

Acromegaly is associated with cardiac hypertrophy, which is believed to be a direct consequence of chronically elevated GH and IGF1. Given that insulin is important for cardiac growth and function, and considering that GH excess induces hyperinsulinemia, insulin resistance, and cardiac alterations, it is of interest to study insulin sensitivity in this tissue under chronic conditions of elevated GH. Transgenic mice overexpressing GH present cardiomegaly and perivascular and interstitial fibrosis in the heart. Mice received an insulin injection, the heart was removed after 2 min, and immunoblotting assays of tissue extracts were performed to evaluate the activation and abundance of insulin-signaling mediators. Insulin-induced tyrosine phosphorylation of the insulin receptor (IR) was conserved in transgenic mice, but the phosphorylation of IR substrate 1 (IRS1), its association with the regulatory subunit of the phosphatidylinositol 3-kinase (PI3K), and the phosphorylation of AKT were decreased. In addition, total content of the glucose transporter GLUT4 was reduced in transgenic mice. Insulin failed to induce the phosphorylation of the mammalian target of rapamycin (mTOR). However, transgenic mice displayed increased basal activation of the IR/IRS1/PI3K/AKT/mTOR and p38 signaling pathways along with higher serine phosphorylation of IRS1, which is recognized as an inhibitory modification. We conclude that GH-overexpressing mice exhibit basal activation of insulin signaling but decreased sensitivity to acute insulin stimulation at several signaling steps downstream of the IR in the heart. These alterations may be associated with the cardiac pathology observed in these animals.
The Need for Vigilance: The Case of a False-Negative Newborn Screen for Cystic Fibrosis
Authors: Dunn Christina T. , Skrypek Mary M. , Powers Amy L. R. , Laguna Theresa A.
Published: July 2011

Cystic fibrosis (CF) is the most common life-limiting recessive genetic disorder in the white population. CF is caused by abnormalities in the gene that codes for the cystic fibrosis transmembrane conductance regulator protein (CFTR) and may result in severe chronic lung disease, poor growth, and malnutrition. Physicians often do not consider CF in the differential diagnosis of an infant with failure to thrive in the presence of a negative newborn screening (NBS) result. In Minnesota, newborn infants are screened for CF by immunoreactive trypsinogen (IRT) testing followed by DNA analysis if the IRT screen result is abnormal. All positive NBS results are followed by confirmatory sweat-testing by pilocarpine iontophoresis. We present here the case of a 1-month-old white boy with failure to thrive, chronic diarrhea, and severe malnutrition. Minnesota state CF NBS results were negative at birth (IRT: 43 ng/mL [96% cutoff value: 52 ng/mL]). Clinical symptoms resulted in sweat-testing by Gibson-Cooke pilocarpine iontophoresis at 1 month of age, and the result was positive (102 mmol Cl−/L [normal: ≤30 mmol Cl−/L]). CFTR mutation analysis confirmed a homozygous f508del genotype, and stool pancreatic elastase testing revealed severe exocrine pancreatic insufficiency. This case represents the first known false-negative result in Minnesota since the initiation of NBS for CF in 2006, which illustrates the importance of considering CF in the evaluation of an infant with failure to thrive and symptoms of malabsorption, regardless of NBS results.