bluuebunny/crossref_metadata_2025 huggingface dataset:
Parallel acquisition of awareness and differential delay eyeblink conditioning
Authors: Weidemann Gabrielle , Antees Cassandra
Published: April 2012

There is considerable debate about whether differential delay eyeblink conditioning can be acquired without awareness of the stimulus contingencies. Previous investigations of the relationship between differential-delay eyeblink conditioning and awareness of the stimulus contingencies have assessed awareness after the conditioning session was finished using a post-experimental questionnaire. In two experiments, the point at which contingency awareness developed during the conditioning session was estimated from a button-press measure of expectancy of the unconditioned stimulus (US). In both experiments, knowledge of the stimulus contingencies and acquisition of differential delay eyeblink conditioning developed approximately in parallel. In Experiment 1 it was shown that predicting the US facilitated eyeblink conditioning compared with predicting the eyeblink response. In Experiment 2, a masking task was used that slowed down the emergence of awareness, and it was shown that differential conditioning only occurred in participants who were able to predict the US. The current findings challenge the hypothesis that differential delay eyeblink conditioning is entirely mediated by a functionally and neurally distinct nondeclarative learning system.
Influence of freshwater flows on the distribution of eggs and larvae of black bream Acanthopagrus butcheri within a drought‐affected estuary
Authors: Williams J. , Hindell J. S. , Swearer S. E. , Jenkins G. P.
Published: April 2012

This study tested the hypothesis that variable freshwater flow in the Gippsland Lakes, Australia, influences the location and extent of environmental conditions suitable for spawning and larval development of black bream, Acanthopagrus butcheri. Freshwater flow had a large influence on the salinity and level of stratification (difference between bottom and surface salinity) in the Gippsland Lakes. Freshwater flows throughout this study varied from no or low flows through to major flooding in 2007. Eggs of A. butcheri were found in similar concentrations throughout the lakes and rivers. More than 99% of larvae, however, were collected from within rivers, with very few larvae being collected from the lakes. A comparison of two spawning seasons revealed that the year with higher freshwater flows also had greater spawning activity and higher concentrations of larvae. Interestingly, there was a significant relationship between the distribution of eggs and larvae with the level of stratification. The highest concentrations of larvae occurred at sites with a difference in bottom and surface salinities of 15–20. This study demonstrates that despite A. butcheri spawning in the lakes and rivers, it is only locations with a halocline that function as larval nursery habitat.
Randomised clinical trial: a comparison between a GerdQ‐based algorithm and an endoscopy‐based approach for the diagnosis and initial treatment of GERD
Authors: Jonasson C. , Moum B. , Bang C. , Andersen K. R. , Hatlebakk J. G.
Published: April 2012

Background

The diagnosis of gastro‐oesophageal reflux disease (GERD) remains challenging. An algorithm, facilitated by a questionnaire, may provide a more structured and cost‐effective care of patients.

Aim

To compare symptom control achieved with empirical therapy for GERD, in an algorithm based on the GerdQ (new structured pathway, NSP), with that of current care after endoscopy (ordinary clinical pathway, OCP).

Methods

Patients with symptoms of GERD, but without alarm features, were randomised in an open, parallel‐group study and followed for 4–8 weeks. In the NSP, GerdQ score was used as a basis for both diagnosis and a treatment algorithm. Patients with high likelihood of GERD were treated empirically with a PPI whereas patients with low likelihood of GERD received therapy chosen by the clinician. In the OCP, diagnosis and treatment were based on endoscopy or pH‐metry findings. The statistical hypothesis was non‐inferiority of NSP to OCP.

Results

A total of 147 patients (86.5%) in the NSP and 133 patients (80.1%) in the OCP arm were responders. Overall, NSP was non‐inferior to OCP, but not superior (P = 0.14). Patients with high likelihood of GERD had significantly better symptom relief in the NSP (P = 0.03), whereas those with low likelihood of GERD showed a numerical difference in favour of an endoscopy‐based approach (OCP). NSP saved 146 € per patient.

Conclusions

A symptom‐based approach using GerdQ reduced health care costs without loss in efficacy. Patients with high likelihood GERD benefited from empirical treatment. An algorithm based on GerdQ may provide physicians with a tool for a more structured care of patients (ClinicalTrials.gov NCT00842387).
Correlation of fasting serum apolipoprotein B‐48 with coronary artery disease prevalence
Authors: Masuda Daisaku , Sugimoto Taizo , Tsujii Ken‐ichi , Inagaki Miwako , Nakatani Kazuhiro , Yuasa‐Kawase Miyako , Tsubakio‐Yamamoto Kazumi , Ohama Tohru , Nishida Makoto , Ishigami Masato , Kawamoto Toshiharu , Matsuyama Akifumi , Sakai Naohiko , Komuro Issei , Yamashita Shizuya
Published: April 2012

Eur J Clin Invest 2012; 42 (9): 992–999

Background  Postprandial hyperlipidemia partially refers to the postprandial accumulation of chylomicrons and chylomicron remnants (CM‐R). Many in vitro studies have shown that CM‐R has highly atherogenic properties, but consensus is lacking on whether CM‐R accumulation correlates with the development of atherosclerotic cardiovascular diseases. We investigated the correlation between CM‐R accumulation and the prevalence of coronary artery disease (CAD).

Design  Subjects who received a coronary angiography and did not take any lipid‐lowering drugs (n = 189) were enrolled. Subjects with coronary artery stenosis (≥ 75%) were diagnosed as CAD. Biochemical markers for glucose and lipid metabolism including fasting apolipoprotein (apo) B‐48 concentration were compared between CAD patients (n = 96) and age‐, sex‐, and body mass index (BMI)‐matched non‐CAD subjects without overt coronary stenosis (< 75%) (n = 67). We tried to determine which metabolic parameters were correlated with the prevalence of CAD by multiple logistic regression analysis, and whether or not the combination of high apo B‐48 and other coronary risk factors (high triglyceride, low HDL‐C, high HbA1c or low adiponectin levels) increased the prevalence of CAD.

Results  Fasting serum apo B‐48 levels were significantly higher in CAD patients than in non‐CAD subjects (3·9 ± 2·4 vs. 6·9 ± 2·6 μg/mL, P < 0·0001) and had the most significant correlation with the existence of CAD. The clustering of high fasting apo B‐48 levels (> 4·34 μg/mL, the cut‐off value) and other coronary risk factors were found to be associated with a stronger risk of CAD compared with single high fasting apo B‐48 levels.

Conclusion  Fasting serum apo B‐48 levels significantly correlated with the prevalence of CAD.
Atopic and non‐atopic eosinophilic oesophagitis are distinguished by immunoglobulin E‐bearing intraepithelial mast cells
Authors: Mulder Daniel J , Mak Nanette , Hurlbut David J , Justinich Christopher J
Published: April 2012

Mulder D J, Mak N, Hurlbut D J & Justinich C J  (2012) Histopathology 61, 810–822

Atopic and non‐atopic eosinophilic oesophagitis are distinguished by immunoglobulin E‐bearing intraepithelial mast cells

Aims:  Eosinophilic oesophagitis (EoE) occurs in atopic individuals and features eosinophils and mast cells, but differences in the inflammatory cell density between the epithelium and lamina propria (LP) are not fully understood. The aim of this study was to determine if numbers of eosinophils, B lymphocytes and immunoglobulin E (IgE)‐bearing mast cells are increased in the mucosa of EoE patients with and without concurrent atopy.

Methods and results:  Oesophageal biopsies containing ≥4 high‐power fields (HPF) of epithelium and LP were identified for normal (n = 9), gastroesophageal reflux disease (GERD) (n = 5) and EoE (n = 25) patients. Patients were classified as atopic or not by clinical history. Immunohistochemistry identified mast cells, B lymphocytes and eosinophils. Eosinophil density was increased in the LP in EoE. Intraepithelial eosinophil density correlated with eosinophils/HPF, CD20+  B lymphocyte density and tryptase+ IgE+ mast cell density. Increased intraepithelial IgE+ cell density in EoE was associated with mast cells and not B lymphocytes. Intraepithelial IgE+ mast cell densities were significantly higher in biopsies from the subgroup of EoE patients with atopy.

Conclusions:  EoE diagnosis using maximal eosinophil count/HPF correlates with average counts/mm2, and intraepithelial eosinophil densities are higher in children than adults with EoE. In EoE, numbers of eosinophils and mast cells are increased in the LP. IgE‐bearing mast cells are increased in atopic EoE patients but not in non‐atopic EoE patients.
Altered brain activation to colorectal distention in visceral hypersensitive maternal‐separated rats
Authors: Wouters M. M. , Van Wanrooy S. , Casteels C. , Nemethova A. , de Vries A. , Van Oudenhove L. , Van den Wijngaard R. M. , Van Laere K. , Boeckxstaens G.
Published: April 2012

Background  Early life trauma can predispose to increased visceral pain perception. Human neuroimaging studies emphasize that altered brain processing may contribute to increased visceral sensitivity. The aim of our study was to evaluate brain responses to painful visceral stimuli in maternal‐separated rats before and after acute stress exposure in vivo.

Methods  H215O microPET scanning was performed during colorectal distention in maternal‐separated rats before and after water avoidance stress. Brain images were anatomically normalized to Paxinos space and analyzed by voxel‐based statistical parametric mapping (SPM2). Colorectal induced visceral pain was assessed by recording of the visceromotor response using abdominal muscle electromyography.

Key Results  Colorectal distention (1.0–2.0 mL) evoked a volume‐dependent increase in visceromotor response in maternal‐separated rats. Stress [water avoidance (WA)] induced an increased visceromotor response to colorectal distention in awake and anesthetized rats. In pre‐WA rats, colorectal distention evoked significant increases in regional blood flow in the cerebellum and periaquaductal gray (PAG). Colorectal distention post‐WA revealed activation clusters covering the PAG as well as somatosensory cortex and hippocampus. At maximal colorectal distention, the frontal cortex was significantly deactivated.

Conclusions & Inferences  WA stress induced increased pain perception as well as activation of the somatosensory cortex, PAG, and hippocampus in maternal‐separated rats. These findings are in line with human studies and provide indirect evidence that the maternal separation model mimics the cerebral response to visceral hypersensitivity in humans.
Biochemical and molecular basis of resistance to ACCase‐inhibiting herbicides in Iranian Phalaris minor populations
Authors: GHEREKHLOO J , OSUNA M D , DE PRADO R
Published: April 2012

Gherekhloo J, Osuna MD & De Prado R (2012). Biochemical and molecular basis of resistance to ACCase‐inhibiting herbicides in Iranian Phalaris minor populations. Weed Research52, 367–372.

Phalaris minor is a common weed in wheat and barley fields of Iran. Repeated use of ACCase inhibiting herbicides during the last two decades to control this weed has resulted in the appearance of populations of P. minor that are resistant to the aryloxyphenoxy propionates (APP) in some wheat fields of the country. Dose–response assays were conducted to investigate the level of resistance in two P. minor populations (AR and MR4) which have developed resistance to three APP herbicides, including diclofop‐methyl, fenoxaprop‐P ethyl and clodinafop propargyl. A high level of resistance in these populations may be due to the presence of an altered ACCase enzyme in these plants, and we hypothesised that one or more mutations in the gene encoding ACCase enzyme are responsible for insensitivity of the enzyme. Results confirmed that resistance in both populations was target site‐based, and molecular studies revealed that substitutions of Trp‐2027‐Cys and Asp‐2078‐Gly, respectively in AR and MR4, are responsible for insensitivity of the enzyme in these populations. This is the first report to show that these substitutions endow resistance to APP herbicides in P. minor, though other resistant biotypes are reported from elsewhere. These mutations may result in resistance of P. minor to some DIM and DEN herbicides. It seems that lack of adequate herbicide and crop rotation has selected plants with different target site mutations, which cause differential responses of the ACCase enzyme to ACCase inhibitors. Additional resistance management practices may be necessary to prevent ACCase‐inhibiting herbicides from becoming ineffective over wide areas.
Ultraviolet induction of antifungal activity in plants
Authors: Schumpp O. , Bruderhofer N. , Monod M. , Wolfender J.‐L. , Gindro K.
Published: April 2012

Ultraviolet‐C irradiation as a method to induce the production of plant compounds with antifungal properties was investigated in the leaves of 18 plant species. A susceptibility assay to determine the antifungal susceptibility of filamentous fungi was developed based on an agar dilution series in microtiter plates. UV irradiation strongly induced antifungal properties in five species against a clinical Fusarium solani strain that was responsible for an onychomycosis case that was resistant to classic pharmacological treatment. The antifungal properties of three additional plant species were either unaffected or reduced by UV‐C irradiation. This study demonstrates that UV‐C irradiation is an effective means of modulating the antifungal activity of very diverse plants from a screening perspective.
Association of MBL2 polymorphism with asthma after bronchiolitis in infancy
Authors: Koponen Petri , He Qiushui , Helminen Merja , Nuolivirta Kirsi , Korppi Matti
Published: April 2012

Background:  Mannose‐binding lectin (MBL) is a component of innate immunity and has been linked with the pathogenesis of asthma. The aim of the present study was to evaluate the association of MBL genotypes with preschool asthma and allergy in children with bronchiolitis in early infancy.

Methods:  In all, 205 infants were hospitalized for bronchiolitis at <6 months of age. Asthma and allergy were studied from a total of 166 children at 6.4 years (mean). A total of 141 (85%) frozen whole blood samples were available for MBL genotyping and MBL2 gene mutations were determined on pyrosequencing for detection of three single‐nucleotide polymorphisms.

Results:  Ninety‐five children (67.4%) had the wild‐type MBL genotype A/A and 46 had A/O or O/O genotypes. Asthma was present in 16 children (11.3%) at 5–7 years of age. Nine children (19.6%) with non‐AA genotype had asthma (vs 7.4% of those with genotype AA, P= 0.03). The result remained significant after adjustment for age, gender and atopy. There were no significant associations between MBL genotypes and asthma at any age before the study. Atopic dermatitis, allergic rhinitis or paternal and/or maternal asthma had no significant associations with MBL genotypes.

Conclusions:  The variant non‐A/A MBL genotype is associated with asthma after bronchiolitis in infancy, but not earlier than at 5–7 years of age.
Major health‐care providers and the 10 leading reasons for adolescent ambulatory visits
Authors: Ku Min‐Sho , Lue Ko‐Huang , Sun Hai‐Lun
Published: April 2012

Background: Epidemiological research underpins the importance of effective health‐care strategies for adolescents. This descriptive study compares the 10 most common diseases among Taiwanese adolescents for 2000 and 2009.

Methods: Data for a total of 69 594 visits in 2000 and 65 802 visits in 2009 by adolescents aged between 10 and 20 years were collected from the National Health Insurance Research Database. A maximum of three outpatient diagnostic codes (International Classification of Disease, ninth revision) could be listed for every visit. The data categories were: principal diagnosis, patient age, and physician specialty.

Results: The middle adolescent age group utilized the least amount of medical services. Respiratory (46.2% in 2000, 40.5% in 2009) and digestive (16.5% in 2000 and 16.9% in 2009) tracts were the leading two diagnostic categories for adolescent ambulatory visits. Teeth (6.8%, 6.1%) and eye (4.0%, 3.1%) problems were also among the top 10 diseases. Family practitioners, ear‐nose‐throat specialists, and traditional Chinese medicine physicians were the major health‐care providers for Taiwanese adolescents, especially in the middle and late groups. Although noted as the first option for consultation in the early group, the role of pediatricians with regard to adolescent health care declined in importance with age.

Conclusions: Nearly 99% of the population in Taiwan is covered under the national health insurance system. The different disease patterns and major health‐care providers between Taiwan and other countries are compared.
Inferring changes in foliar mass and area from foliage cover: A mechanistic model
Authors: HOLLAND E. PENELOPE
Published: April 2012

Measuring foliar area or mass directly is destructive, and precludes long‐term, repeated observations of individual trees as they suffer or recover from foliar damage. Instead, foliage cover indices are often used as a proxy for foliar mass. Patterns of fluctuations in foliage cover indices can be used to infer qualitative changes in canopy health. However, foliage cover is not necessarily linearly related to foliar area or mass, and this may confound the detection of significant foliar damage, and comparisons of herbivore browse impacts between individual trees, tree species or sites. I derived a mechanistic model to quantify the relationship between foliar area or mass and foliage cover measured as the proportion of sky occluded by leaves. This one parameter model is close to linear for single‐tiered trees, but increasingly non‐linear for multi‐tiered trees. I compared the non‐linear model to a linear model using foliage cover data from an artificial defoliation experiment on two single‐tiered, sub‐canopy species and from simulated photographic images of single‐ and multi‐tiered canopies. The non‐linear model had lower errors than the linear model, and errors did not increase with foliage density (leaf area per unit area), variation (of leaf sizes within and between canopies) or leaf geometry. The non‐linear model can be easily parameterized from relatively low‐cost observations of foliage cover, independently of empirical measurements of foliar area or mass, and is applicable to a wide range of tree species. It should therefore help managers quantify how changes in foliage cover due to natural fluctuations or foliar damage affect foliar area and mass, and can be used to quantify parameters for models of browse impacts in mixed forest.
Serotonin2C receptors in the nucleus accumbens are involved in enhanced alcohol‐drinking behavior
Authors: Yoshimoto Kanji , Watanabe Yoshihisa , Tanaka Masaki , Kimura Minoru
Published: April 2012

Dopamine and serotonin (5‐HT) in the nucleus accumbens (ACC) and ventral tegmental area of the mesoaccumbens reward pathways have been implicated in the mechanisms underlying development of alcohol dependence. We used a C57BL/6J mouse model with increased voluntary alcohol‐drinking behavior by exposing the mice to alcohol vapor for 20 consecutive days. In the alcohol‐exposed mice, the expression of 5‐HT2C receptor mRNA increased in the ACC, caudate nucleus and putamen, dorsal raphe nucleus (DRN), hippocampus and lateral hypothalamus, while the protein level of 5‐HT2C receptor significantly increased in the ACC. The expression of 5‐HT7 receptor mRNA increased in the ACC and DRN. Contents of 5‐HT decreased in the ACC shell (ACCS) and DRN of the alcohol‐exposed mice. The basal extracellular releases of dopamine (DA) and 5‐HT in the ACCS increased more in the alcohol‐exposed mice than in alcohol‐naïve mice. The magnitude of the alcohol‐induced ACCS DA and 5‐HT release in the alcohol‐exposed mice was increased compared with the control mice. Intraperitoneal (i.p.) administration or local injection into ACCS of the 5‐HT2C receptor antagonist, SB‐242084, suppressed voluntary alcohol‐drinking behavior in the alcohol‐exposed mice. But the i.p. administration of the 5‐HT7 receptor antagonist, SB‐258719, did not have significant effects on alcohol‐drinking behavior in the alcohol‐exposed mice. The effects of the 5‐HT2C receptor antagonist were not observed in the air‐exposed control mice. These results suggest that adaptations of the 5‐HT system, especially the upregulation of 5‐HT2C receptors in the ACCS, are involved in the development of enhanced voluntary alcohol‐drinking behavior.
Effects of oral isosorbide and glycerol on intraocular pressure, serum osmolality, and blood glucose in normal dogs
Authors: Wasserman Neal T. , Kennard Gavin , Cochrane Zachary N. , Felchle Lisa M.
Published: April 2012

Objective  To evaluate and compare the effects of oral isosorbide and glycerol on intraocular pressure (IOP), serum osmolality (SOSM), and blood glucose (BG) in normal dogs.

Methods  Ten normal dogs were administered an oral dose of either isosorbide (1.5 g/kg), glycerol (1.5 g/kg) or control (water, 2 mL/kg) in a double blind protocol.

Prior to dosing, baseline IOP, SOSM, and BG were measured in all dogs. IOP was subsequently evaluated every 30 min for 6 h post‐dosing. BG and SOSM were reassessed at times 1, 2, 4, and 6 h post‐dosing. After 1‐week washout periods, every dog was subject to each of the three treatments. The dogs were held NPO for 4 h after dosing.

Results  The maximal decrease in IOP was 17% by 1 h and 13.5% by 30 min after glycerol and isosorbide administration, respectively. However, the overall changes in IOP were not significant when compared to the controls. SOSM increased above baseline after dosing with glycerol but decreased after isosorbide, which difference was significant at 1, 2, and 4 h post‐administration. BG significantly increased after administration of glycerol relative to the control but was not significantly affected by isosorbide.

Conclusions  Neither glycerol nor isosorbide significantly affected IOP when compared to the control. However, glycerol induced significant elevations in both BG relative to the control and SOSM relative to isosorbide.
Towards a relational framework for pathological gambling (Part I): Five circuits
Authors: Lee Bonnie K.
Published: April 2012

Relationship patterns before and after pathological gambling were investigated qualitatively using eight in‐depth clinical case studies in which one partner met Diagnostic and Statistical Manual of Mental Disorders‐IV pathological gambling criteria. Five circuits of couple interactions are described: (i) fault‐lines; (ii) pressure points; (iii) escalation; (iv) relapse and (v) congruence. The exploration of these circuits is developed in two complementary articles. This first article delineates the first four circuits as recursive self‐perpetuating cycles of couple distress in systemic interaction with pathological gambling development and relapse. The second article delineates how a couple can be helped to extricate themselves from these recursive circuits through ‘congruence’. Implications of this relational formulation of pathological gambling for conceptualization, assessment and treatment are discussed.
Weather‐related Employment Subsidies as a Remedy for Seasonal Unemployment? Evidence from Germany
Authors: Arntz Melanie , Wilke Ralf A.
Published: April 2012

Many European countries try to reduce seasonal unemployment by subsidizing short‐time employment during the winter period. Despite such costly efforts, pronounced seasonal unemployment patterns continue to exist. This puts doubts on the effectiveness of such policy interventions. This paper provides a first empirical assessment of the effectiveness of different subsidy schemes by exploiting the institutional variation in a German subsidy scheme that applies to the construction sector and the variation in local weather and business cycle conditions across 20 years. The findings confirm that generous short‐time subsidies reduce individual lay‐off probabilities in the case of poor weather conditions. However, the link between weather conditions and seasonal lay‐offs is much less strong than expected, making planned capacity reductions the main suspect for causing seasonality in unemployment patterns.
Investigative and Suspensive Scepticism
Authors: Grgić Filip
Published: April 2012

Sextus Empiricus portrays the Pyrrhonian sceptics in two radically different ways. On the one hand, he describes them as inquirers or examiners, and insists that what distinguishes them from all the other philosophical schools is their persistent engagement in inquiry. On the other hand, he insists that the main feature of Pyrrhonian attitude is suspension of judgement about everything. Many have argued that a consistent account of Sextan scepticism as both investigative and suspensive is not possible. The main obstacle to characterizing Pyrrhonism as both investigative and suspensive is the fact that it seems that the mature sceptics, after they have suspended judgement and thus reached tranquillity, have no motivation for further inquiry. Any inquiry they seem to be interested in after they have suspended judgement is the refutation of (relevant) beliefs needed for maintaining tranquillity. I try to show that the mature sceptics' removal of distress does notipso factomean removal of the desire for knowledge. This is because distress is not just a matter of unsatisfied desire, but of belief that one of the opposed appearances must be true, or, more generally, of belief that the truth is the only worthwhile epistemic goal. Having abandoned this belief, the sceptics can still engage in philosophical inquiries. This is because Sextus does not assume that philosophy is the search for truth: it is so only for the dogmatists. In a more general sense, applicable to the sceptics as well, philosophy is just an inquiry into certain things, and for the sceptics, its epistemic goal is still open.
Estradiol levels predict short‐term adverse health outcomes in postmenopausal acute stroke women
Authors: Pappa T. , Vemmos K. , Mantzou E. , Savvari P. , Stamatelopoulos K. , Alevizaki M.
Published: April 2012

Background:  Data on the role of endogenous sex steroids in cerebrovascular disease are sparse. Estradiol is a hormone with diverse actions on the central nervous system. Our aim was to investigate the role of circulating estradiol levels in a postmenopausal acute stroke population.

Methods:  During a time‐period of 2 years, we prospectively studied 302 postmenopausal female patients hospitalized for an acute stroke in two tertiary hospitals. We addressed the question whether endogenous estradiol is associated with stroke severity on admission and functional outcome 1 month after stroke, as assessed by the National Institutes of Health Stroke Scale (NIHSS) and modified Rankin Scale (mRS), respectively.

Results:  Estradiol levels were significantly related to stroke severity on admission, as expressed by NIHSS, even after correcting for confounding factors in the multivariate analysis (beta 0.353, P < 0.001). Estradiol was an independent determinant of 1‐month mortality and adverse functional outcome (mRS ≥ 4), [odds ratio (OR) with 95% confidence intervals (CI): 3.341 (1.617–6.902), P = 0.001 and 2.277 (1.273–4.074), P = 0.006, respectively].

Conclusions:  We identified an independent association of endogenous estradiol levels with stroke severity and short‐term mortality and outcome. These findings suggest challenging the role of estradiol as a neuroprotective agent.
Comparison of density estimation methods for mammal populations with camera traps in the Kaa‐Iya del Gran Chaco landscape
Authors: Noss A. J. , Gardner B. , Maffei L. , Cuéllar E. , Montaño R. , Romero‐Muñoz A. , Sollman R. , O'Connell A. F.
Published: April 2012

Sampling animal populations with camera traps has become increasingly popular over the past two decades, particularly for species that are cryptic, elusive, exist at low densities or range over large areas. The results have been widely used to estimate population size and density. We analyzed data from 13 camera trap surveys conducted at five sites across the Kaa‐Iya landscape, Bolivian Chaco, for jaguar, puma, ocelot and lowland tapir. We compared two spatially explicit capture–recapture (SCR) software packages: secr, a likelihood‐based approach, and SPACECAP, a Bayesian approach, both of which are implemented within the R environment and can be used to estimate animal density from photographic records of individual animals that simultaneously employ spatial information about the capture location relative to the sample location. As a non‐spatial analysis, we used the program CAPTURE 2 to estimate abundance from the capture–recapture records of individuals identified through camera trap photos combined with an ad hoc estimation of the effective survey area to estimate density. SCR methods estimated jaguar population densities from 0.31 to 1.82 individuals per 100 km2 across the Kaa‐Iya sites; puma from 0.36 to 7.99; ocelot from 1.67 to 51.7; and tapir from 7.38 to 42.9. Density estimates using either secr or SPACECAP were generally lower than the estimates generated using the non‐spatial method for all surveys and species; and density estimates using SPACECAP were generally lower than that using secr. We recommend using either secr or SPACECAP because the spatially explicit methods are not biased by an informal estimation of an effective survey area. Although SPACECAP and secr are less sensitive than non‐spatial methods to the size of the grid used for sampling, we recommend grid sizes several times larger than the average home range (known or estimated) of the target species.
Echogenicity of the carotid intima–media complex and cardiovascular risk factors
Authors: De Blois Jonathan , Stranden Einar , Jogestrand Tomas , Henareh Loghman , Agewall Stefan
Published: April 2012

Introduction

Increased carotid intima–media thickness (IMT) has been associated with increased risk of myocardial infarction (MI) and stroke. A measure of echogenicity, the grey scale median (GSM), has been shown to be inversely correlated with cardiovascular risk factors and to be predictive of mortality in a community‐based cohort. We assessed the factors associated with carotid IM–GSM in younger, non‐diabetic patients with a recent MI.

Methods and results

A total of 122 patients (women, 25%) aged 31–80 years (61) were recruited 2–3 days after an acute MI. Ultrasound examinations of the carotid arteries were performed 1–12 months after the MI. IMT was 0·78 (SD 0·17) mm on the right side and 0·81 (0·20) mm on the left side (P = 0·05). GSM was 88·60 (range 46–132, SD 18·32) on the right side and 82·10 (40–126, 17·89) on the left side (P = 0·002). Triglycerides (TG) correlated with GSM on both sides (right, r = −0·27, P = 0·003; left, r = −0·18, P = 0·05). On the right side, GSM was 92·15 and 82·26 (P = 0·05) in patients with TG < and ≥1·7, and on the left side, it was 84·04 and 74·55 (P = 0·02) in patients with TG < and ≥2·3. On multivariate analysis, TG were significantly associated with GSM, both on the right side (P = 0·01) and on the left side (P = 0·009).

Conclusion

We found a negative association between TG and carotid IM–GSM on both sides in patients with a recent MI. Our results also suggest that atherosclerosis progression may be faster on the left side in patients with coronary heart disease.
Optical quality for keratoconic eyes with conventional RGP lens and simulated, customised contact lens corrections: a comparison
Authors: Jinabhai Amit , Neil Charman W , O’Donnell Clare , Radhakrishnan Hema
Published: April 2012

Citation information: Jinabhai A, Charman WN, O’Donnell C & Radhakrishnan H. Optical quality for keratoconic eyes with conventional RGP lens and simulated, customised contact lens corrections: a comparison. Ophthalmic Physiol Opt 2012, 32, 200–212. doi: 10.1111/j.1475‐1313.2012.00904.x

Purpose:  To compare monochromatic aberrations of keratoconic eyes when uncorrected, corrected with spherically‐powered RGP (rigid gas‐permeable) contact lenses and corrected using simulations of customised soft contact lenses for different magnitudes of rotation (up to 15°) and translation (up to 1 mm) from their ideal position.

Methods:  The ocular aberrations of examples of mild, moderate and severe keratoconic eyes were measured when uncorrected and when wearing their habitual RGP lenses. Residual aberrations and point‐spread functions of each eye were simulated using an ideal, customised soft contact lens (designed to neutralise higher‐order aberrations, HOA) were calculated as a function of the angle of rotation of the lens from its ideal orientation, and its horizontal and vertical translation.

Results:  In agreement with the results of other authors, the RGP lenses markedly reduced both lower‐order aberrations and HOA for all three patients. When compared with the RGP lens corrections, the customised lens simulations only provided optical improvements if their movements were constrained within limits which appear to be difficult to achieve with current technologies.

Conclusions:  At the present time, customised contact lens corrections appear likely to offer, at best, only minor optical improvements over RGP lenses for patients with keratoconus. If made in soft materials, however, these lenses may be preferred by patients in term of comfort.
Employee Selection as a Control System
Authors: CAMPBELL DENNIS
Published: April 2012

Theories from the economics, management control, and organizational behavior literatures predict that when it is difficult to align incentives by contracting on output, aligning preferences via employee selection may provide a useful alternative. This study investigates this idea empirically using personnel and lending data from a financial services organization that implemented a highly decentralized business model. I exploit variation in this organization in whether or not employees are selected via channels that are likely to sort on the alignment of their preferences with organizational objectives. I find that employees selected through such channels are more likely to use decision‐making authority in the granting and structuring of consumer loans than those who are not. Conditional on using decision‐making authority, their decisions are also less risky ex post. These findings demonstrate employee selection as an important, but understudied, element of organizational control systems.
Adult Polycystic Kidney Disease: Who Needs Hospital Follow‐Up?
Authors: Griveas Ioannis , Bishop Kathryn , World Michael
Published: April 2012

Clinical data from 120 adult patients with genetically undifferentiated polycystic kidney disease who had been followed up for more than 3 months (range 3–172) were reviewed in order to try to identify clinical indicators that might predict deterioration in renal function. They were split into two groups dependent on whether annualized fall in estimated glomerular filtration rate (ΔeGFR mL/min/1.73 m2/year) was statistically significant or not. Only 26 patients (22%) had a statistically significantly decreasing ΔeGFR with a median decrease of −2.6 mL/min/1.73 m2/year (range −6.2 to −0.7). There was no difference in initial age, gender, or racial distributions between the groups or in initial eGFR. Follow‐up was longer (median 86, range 23–172 months vs. 46, range 3–161 months; P =  0.002) and initial blood pressure values tended to be lower (with mean systolic values of 128 vs. 148 mm Hg; P = 0.02) in the group with statistically significant fall in ΔeGFR, but this trend failed to achieve an a priori level of statistical significance. However, the proportion of patients with initial systolic blood pressure ≤144 developing a statistically significant fall in ΔeGFR was 0.26 (95% confidence interval = 0.13 to 0.45). No differences were found in initial hemoglobin or cholesterol concentrations. Overall, the annualized rate of decrease in eGFR tended to be greater in those with the higher initial eGFR (P = 0.04), but correlation was poor (rho2= 0.04) and failed to achieve an a priori level of statistical significance. No statistically significant correlation was found between ΔeGFR and any other variable. Only those patients with polycystic kidney disease with a statistically significant annualized decrease in eGFR may need to be referred for hospital follow‐up in the renal clinic. This simple selection would reduce referrals by 78%.
Physiological Performance of a Detergent Decellularized Heart Valve Implanted for 15 Months in Vietnamese Pigs: Surgical Procedure, Follow‐up, and Explant Inspection
Authors: Gallo Michele , Naso Filippo , Poser Helen , Rossi Antonio , Franci Paolo , Bianco Roberto , Micciolo Matteo , Zanella Fabio , Cucchini Umberto , Aresu Luca , Buratto Edward , Busetto Roberto , Spina Michele , Gandaglia Alessandro , Gerosa Gino
Published: April 2012

This study features the longest experimental follow‐up for decellularized heart valves implanted in an animal model. Porcine aortic heart valves were decellularized according to a disclosed standardized method in which TRITON X‐100 and sodium cholate (TRICOL) are used in succession, followed by a further treatment with the endonuclease Benzonase to completely remove the nucleic acid remnants. Experimental animals (n = 17), represented by Vietnamese pigs (VPs), received a decellularized aortic allograft as a substitute for the replacement of their right ventricular outflow tract. The surgical implantation of the TRICOL‐treated aortic valve conduit was successful in 11 VPs, while perioperative or postoperative complications occurred in the remaining six animals. In the sham‐operated group (n = 4), the native pulmonary root was excised and immediately reimplanted orthotopically in the same animal. Echocardiography demonstrated a satisfactory hemodynamic performance of the TRICOL‐treated valves during follow‐up as well as the absence of relevant leaflet alterations concerning thickness and motility or valve insufficiency. At explantation, macroscopic inspection of tissue‐engineered heart valve conduits did not evidence calcifications and showed a decreased wall thickness, comparable to that of the reimplanted native pulmonary roots. Noteworthy, extended functional performance, recovery of DNA content, and active extracellular matrix precursor incorporation are apparently compatible with the properties of a living self‐supporting substitute.
Prosthodontic Rehabilitation for Total Glossectomy with a Magnetic Detachable Mandibular Tongue Prosthesis: A Clinical Report
Authors: Sabouri Amir A. , Safari Anahita , Gharechahi Jafar , Esmailzadeh Samira
Published: April 2012

Total glossectomy can result in significant functional impairments in mastication, swallowing, and speech. In addition to these functional problems, severe psychological problems may follow complete loss of the tongue. Placement of a mandibular tongue prosthesis obturates this large defect, increases the patient's ability to produce intelligible sounds, and assists with a return to a normal diet. Prosthetic rehabilitation can also improve the user's appearance and psychosocial adjustment. This clinical report describes a magnetically attached two‐piece tongue prosthesis used to treat a patient who underwent total glossectomy.
An Econometric Model of the Term Structure of Interest‐Rate Swap Yields
Authors: DUFFIE DARRELL , SINGLETON KENNETH J.
Published: April 2012

This article develops a multi‐factor econometric model of the term structure of interest‐rate swap yields. The model accommodates the possibility of counterparty default, and any differences in the liquidities of the Treasury and Swap markets. By parameterizing a model of swap rates directly, we are able to compute model‐based estimates of the defaultable zero‐coupon bond rates implicit in the swap market without having to specify a priori the dependence of these rates on default hazard or recovery rates. The time series analysis of spreads between zero‐coupon swap and treasury yields reveals that both credit and liquidity factors were important sources of variation in swap spreads over the past decade.
The Cyclical Behavior of Interest Rates
Authors: ROMA ANTONIO , TOROUS WALTER
Published: April 2012

This article investigates the behavior of the term structure of interest rates over the business cycle. In contrast to prior studies that measure the business cycle by the simple growth in aggregate economic activity, we consider the deviation of aggregate economic activity from its potentially stochastic trend. We show that incorporating both an independent trend and cyclical component in consumption improves the efficiency in estimating consumption‐based asset pricing models. We also find that the term spread is more informative about future changes in stochastically detrended real gross domestic product (GDP) than future growth rates in real GDP.
The Market for Equity Options in the 1870s
Authors: KAIRYS JOSEPH P. , VALERIO NICHOLAS
Published: April 2012

The introduction of exchange‐traded options in 1973 led to explosive growth in the stock options market, but put and call options on equity securities have existed for more than a century. Prior to the listing of option contracts, trading was conducted in an order‐driven over‐the‐counter market. From 1873 to 1875, quotes for options contracts were published weekly in The Commercial and Financial Chronicle during a period that saw extensive marketing efforts by a number of brokerage firms. In this article we examine these quotes to determine why this seemingly sophisticated market existed for only a brief period in financial history.
Market Segmentation and Stock Prices: Evidence from an Emerging Market
Authors: DOMOWITZ IAN , GLEN JACK , MADHAVAN ANANTH
Published: April 2012

We examine the relationship between stock prices and market segmentation induced by ownership restrictions in Mexico. The focus is on multiple classes of equity that differentiate between foreign and domestic traders, and between domestic individuals and institutions. Significant stock price premia are documented for shares not restricted to a particular investor group. We analyze the theoretical and empirical determinants of premia across firms and over time. In addition to economy‐wide factors, segmentation reflects the relative scarcity of unrestricted shares. The results provide additional support for Stulz and Wasserfallen's (1995) hypothesis that firms discriminate between investor groups with different demand elasticities.
Symposium on Public Policy Issues in Finance
Authors: LELAND HAYNE E. , FELDSTEIN MARTIN , GLAUBER ROBERT R. , MULLINS DAVID W. , WALLMAN STEVEN M. H.
Published: April 2012

The thesis of this symposium, organized by James Bicksler, was that while finance theory will surely inform practitioners, it seems appropriate to pay some attention to the opposite flow: practitioners can inform theory. Contributors include a distinguished group of practitioners with extensive backgrounds in economics, and economists with extensive public policy experience: Martin Feldstein, Robert Glauber, David Mullins, and Steven Wallman. Their topics range from privatizing social security, to managing market crashes, to the regulatory agency cost problem, to regulatory constraints in a technologically advanced world.
Myth or Reality? The Long‐Run Underperformance of Initial Public Offerings: Evidence from Venture and Nonventure Capital‐Backed Companies
Authors: BRAV ALON , GOMPERS PAUL A.
Published: April 2012

We investigate the long‐run underperformance of recent initial public offering (IPO) firms in a sample of 934 venture‐backed IPOs from 1972–1992 and 3,407 nonventure‐backed IPOs from 1975–1992. We find that venture‐backed IPOs outperform non‐venture‐backed IPOs using equal weighted returns. Value weighting significantly reduces performance differences and substantially reduces underperformance for nonventure‐backed IPOs. In tests using several comparable benchmarks and the Fama‐French (1993) three factor asset pricing model, venture‐backed companies do not significantly underperform, while the smallest nonventure‐backed firms do. Underperformance, however, is not an IPO effect. Similar size and book‐to‐market firms that have not issued equity perform as poorly as IPOs.
Trading Costs and Exchange Delisting: The Case of Firms that Voluntarily Move from the American Stock Exchange to the Nasdaq
Authors: CLYDE PAUL , SCHULTZ PAUL , ZAMAN MIR
Published: April 2012

We examine 47 stocks that voluntarily left the American Stock Exchange from 1992 through 1995 and listed on the Nasdaq. We find that both effective and quoted spreads increase by about 100 percent after listing on the Nasdaq. These spread changes are consistent across stocks. In contrast, excess returns are positive when firms announce a switch from The American Stock Exchange to the Nasdaq. We are unable to explain this apparent contradiction.
Transactions Costs and Capital Structure Choice: Evidence from Financially Distressed Firms
Authors: GILSON STUART C.
Published: April 2012

This study provides evidence that transactions costs discourage debt reductions by financially distressed firms when they restructure their debt out of court. As a result, these firms remain highly leveraged and one‐in‐three subsequently experience financial distress. Transactions costs are significantly smaller, hence leverage falls by more and there is less recurrence of financial distress, when firms recontract in Chapter 11. Chapter 11 therefore gives financially distressed firms more flexibility to choose optimal capital structures.
Equity Issuance and Adverse Selection: A Direct Test Using Conditional Stock Offers
Authors: HOUSTON JOEL F. , RYNGAERT MICHAEL D.
Published: April 2012

We conduct a unique test of adverse selection in the equity issuance process. While common stock is the dominant means of payment in bank mergers, stock acquisition agreements provide target shareholders with varying degrees of protection against adverse price movements in the bidder's stock between the time of the merger agreement and the time of merger completion. We show that it is the degree of protection against adverse price changes and not the percent of stock offered in a bank merger that explains bidder merger announcement abnormal returns. This result is difficult to explain outside of an adverse selection framework.
Competition and Collusion in Dealer Markets
Authors: DUTTA PRAJIT K. , MADHAVAN ANANTH
Published: April 2012

This article develops a game‐theoretic model to analyze market makers' intertemporal pricing strategies. We show that dealers who adopt noncooperative pricing strategies may set bid‐ask spreads above competitive levels. This form of “implicit collusion” differs from explicit collusion, where dealers cooperate to fix prices. Price discreteness or asymmetric information are not required for collusion to occur. Rather, institutional arrangements that restrict access to the order flow are important determinants of the ability to collude because they reduce dealers' incentives to compete on price. Public policy efforts to increase interdealer competition should focus on such restrictions.
Third Market Broker‐Dealers: Cost Competitors or Cream Skimmers?
Authors: BATTALIO ROBERT H.
Published: April 2012

This article compares the bid‐ask spread for New York Stock Exchange (NYSE)‐listed securities before and after a major third market broker‐dealer, Bernard L. Madoff Investment Securities (Madoff), begins to selectively purchase and execute orders in those securities. Tests reveal the quoted bid‐ask spread tightens when Madoff enters the market. Furthermore, trading costs as measured by the difference between the transaction price and the midpoint of the contemporaneous bid‐ask spread do not increase. Together, these results suggest that the adverse selection problem associated with allowing agents to selectively execute orders in exchange‐listed securities may be economically insignificant.