bluuebunny/crossref_metadata_2025 huggingface dataset:
CagA-positive Helicobacter pylori infection is not associated with decreased risk of Barrett's esophagus in a population with high H. pylori infection rate
Authors: Ferrández Angel , Benito Rafael , Arenas Juan , García-González María Asunción , Sopeña Federico , Alcedo Javier , Ortego Javier , Sainz Ricardo , Lanas Angel
Published: February 2006

Background & aim

The role that H. pylori infection plays in the development of and Barrett's esophagus (BE) is uncertain. We tested the hypothesis that infection with cagA+ Helicobacter pylori strains protects against the development of BE.

Methods

We studied 104 consecutive patients, residents in an area with a high prevalence of H. pylori infection, with BE and 213 sex- and age-matched controls. H. pylori infection and CagA antibody status were determined by western blot serology.

Results

H. pylori prevalence was higher in patients with BE than in controls (87.5% vs. 74.6%; OR. 2.3; 95% CI: 1.23–4.59). Increasing age was associated with a higher prevalence of H. pylori (p < 0.05). The prevalence of CagA+ H. pylori serology was similar in patients with BE and controls (64.4% vs. 54.5%; NS). Type I H. pylori infection (CagA+ and VacA+) was similar in patients with BE and controls (44.2% vs. 41.3%; NS). Logistic regression analysis identified alcohol (O.R. 7.09; 95% CI 2.23–22.51), and H. pylori infection (OR: 2.41; 95%CI: 1.20–4.84) but not CagA+ serology as independent factors.

Conclusion

Neither H. pylori infection nor H. pylori infection by CagA+ strains reduce the risk of BE in a population with high prevalence of H. pylori infection.
Nosocomial bloodstream infections caused by Klebsiella pneumoniae: impact of extended-spectrum β-lactamase (ESBL) production on clinical outcome in a hospital with high ESBL prevalence
Authors: Marra Alexandre R , Wey Sérgio B , Castelo Adauto , Gales Ana Cristina , Cal Ruy Guilherme R , Filho José R do Carmo , Edmond Michael B , Pereira Carlos Alberto P
Published: February 2006

Background

The frequency of ESBL producing Klebsiella pneumoniae bloodstream infections (BSI) is high in Brazilian hospitals, however little is known regarding what role, if any, resistance plays in the expected outcome in hospitals with a high prevalence of these pathogens.

Methods

From 1996 to 2001, hospital acquired K. pneumoniae BSI were evaluated retrospectively. Each patient was included only once at the time of BSI. ESBL producing strains were identified using the E-test method. The association of variables with the mortality related to bacteremia was included in a stepwise logistic regression model.

Results

One hundred and eight hospital acquired K. pneumoniae BSI met criteria for inclusion. Fifty two percent were due to ESBL producing strains. The overall in-hospital mortality was 40.8%. Variables independently predicting death by multivariate analysis were the following: mechanical ventilation (p = 0.001), number of comorbidities (p = 0.003), antimicrobials prescribed before bacteremia (p = 0.01) and fatal underlying disease (p = 0.025).

Conclusion

Bacteremia due to ESBL producing K. pneumoniae strains was not an independent predictor for death in patients with BSI. An increased mortality in hospital-acquired BSI by K. pneumoniae was related to the requirement for mechanical ventilation, more than two comorbidities, the previous use of two or more antibiotics, and the presence of a rapidly fatal disease.
Coarctation of the aorta and mild to moderate developmental delay in a child with a de novo deletion of chromosome 15(q21.1q22.2)
Authors: Lalani Seema R , Sahoo Trilochan , Sanders Merideth E , Peters Sarika U , Bejjani Bassem A
Published: February 2006

Background

Deletion of 15q21q22 is a rare chromosomal anomaly. To date, there have been nine reports describing ten individuals with different segmental losses involving 15q21 and 15q22. Many of these individuals have common features of growth retardation, hypotonia and moderate to severe mental retardation. Congenital heart disease has been described in three individuals with interstitial deletion involving this region of chromosome 15.

Case presentation

We report a child with coarctation of the aorta, partial agenesis of corpus callosum and mild to moderate developmental delay, with a de novo deletion of 15q21.1q22.2, detected by the array Comparative Genomic Hybridization (CGH). We utilized chromosome 15-specific microarray-based CGH to define the chromosomal breakpoints in this patient.

Conclusion

This is the first description of mapping of an interstitial deletion involving the chromosome 15q21q22 segment using the chromosome 15-specific array-CGH. The report also expands the spectrum of clinical phenotype associated with 15q21q22 deletion.
An analysis of sickness absence in chronically ill patients receiving Complementary and Alternative Medicine: A longterm prospective intermittent study
Authors: Moebus Susanne , Lehmann Nils , Bödeker Wolfgang , Jöckel Karl-Heinz
Published: February 2006

Background

The popularity of complementary and alternative medicine (CAM) has led to a growing amount of research in this area. All the same little is known about the effects of these special treatments in every-day practice of primary care, delivered by general practitioners within the health insurance system. From 1994 to 2000 more than 20 German Company health insurances initiated the first model project on CAM according to the German social law. Aim of this contribution is to investigate the effectiveness of multi-modal CAM on chronic diseases within primary health care.

Methods

A long-term prospective intermittent study was conducted including 44 CAM practitioners and 1221 self-selected chronically ill patients (64% women) of whom 441 were employed. Main outcome measure is sick-leave, controlled for secular trends and regression-to-the mean and self-perceived health status.

Results

Sick-leave per year of 441 patients at work increased from 22 (SD ± 45.2) to 31 (± 61.0) days within three years prior to intervention, and decreased to 24 (± 55.6) in the second year of treatment, sustaining at this level in the following two years. Detailed statistical analysis show that this development exceeds secular trends and the regression-toward-the-mean effect. Sick-leave reduction was corroborated by data on self-reported improvement of patients' health status.

Conclusion

Results of this longterm observational study show a reduction of sick leave in chronically ill patients after a complex multimodal CAM intervention. However, as this is an uncontrolled observational study efficacy of any specific CAM treatment can not be proven. The results might indicate an general effectiveness of CAM in primary care, worthwhile further investigations. Future studies should identify the most suitable patients for CAM practices, the most appropriate and safe treatments, provide information on the magnitude of the effects to facilitate subsequent definitive randomised controlled studies that will help to position complementary and alternative medicine in health care.
Advising overweight persons about diet and physical activity in primary health care: Lithuanian health behaviour monitoring study
Authors: Klumbiene Jurate , Petkeviciene Janina , Vaisvalavicius Vytautas , Miseviciene Irena
Published: February 2006

Background

Obesity is a globally spreading health problem. Behavioural interventions aimed at modifying dietary habits and physical activity patterns are essential in prevention and management of obesity. General practitioners (GP) have a unique opportunity to counsel overweight patients on weight control. The purpose of the study was to assess the level of giving advice on diet and physical activity by GPs using the data of Lithuanian health behaviour monitoring among adult population.

Methods

Data from cross-sectional postal surveys of 2000, 2002 and 2004 were analysed. Nationally representative random samples were drawn from the population register. Each sample consisted of 3000 persons aged 20–64 years. The response rates were 74.4% in 2000, 63.4% in 2002 and 61.7% in 2004. Self-reported body weight and height were used to calculate body mass index (BMI). Information on advising in primary health care was obtained asking whether GP advised overweight patients to change dietary habits and to increase physical activity. The odds of receiving advice on diet and physical activity were calculated using multiple logistic regression analyses according to a range of sociodemographic variables, perceived health, number of visits to GPs and body-weight status.

Results

Almost a half of respondents were overweight or obese. Only one fourth of respondents reported that they were advised to change diet. The proportion of persons who received advice on physical activity was even lower. The odds of receiving advice increased with age. A strong association was found between perceived health and receiving advice. The likelihood of receiving advice was related to BMI. GPs were more likely to give advice when BMI was high. More than a half of obese respondents (63.3%) reported that they had tried to lose weight. The association between receiving advice and self-reported attempt to lose weight was found.

Conclusion

The low rate of dietary and physical activity advice reported by overweight patients implies that more lifestyle counselling should be provided in primary health care. There is an obvious need for improved training and education of GPs in counselling of overweight patients focusing on methods of giving dietary and physical activity advice.
Private provider participation in statewide immunization registries
Authors: Clark Sarah J , Cowan Anne E , Bartlett Diana L
Published: February 2006

Background

Population-based registries have been promoted as an effective method to improve childhood immunization rates, yet rates of registry participation in the private sector are low. We sought to describe, through a national overview, the perspectives of childhood immunization providers in private practice regarding factors associated with participation or non-participation in immunization registries.

Methods

Two mailed surveys, one for 264 private practices identified as registry non-participants and the other for 971 identified as registry participants, from 15 of the 31 states with population-based statewide immunization registries. Frequency distributions were calculated separately for non-participants and participants regarding the physician-reported factors that influenced decisions related to registry participation. Pearson chi-square tests of independence were used to assess associations among categorical variables.

Results

Overall response rate was 62% (N = 756). Among non-participants, easy access to records of vaccines provided at other sites (N = 101, 68%) and printable immunization records (N = 82, 55%) were most often cited as "very important" potential benefits of a registry, while the most commonly cited barriers to participation were too much cost/staff time (N = 36, 38%) and that the practice has its own system for recording and monitoring immunizations (N = 35, 37%). Among registry participants, most reported using the registry to input data on vaccines administered (N = 326, 87%) and to review immunization records of individual patients (N = 302, 81%). A minority reported using it to assess their practice's immunization coverage (N = 110, 29%) or generate reminder/recall notices (N = 54, 14%). Few participants reported experiencing "significant" problems with the registry; the most often cited was cost/staff time to use the registry (N = 71, 20%).

Conclusion

Most registry participants report active participation with few problems. The problems they report are generally consistent with the barriers anticipated by non-participants, but did not impede participation. Recruitment efforts should focus on demonstrating the benefits of the registry to providers. In addition, many participants are not utilizing the full range of registry features; further study is needed to determine how best to increase use of these features.
Regular use of a hand cream can attenuate skin dryness and roughness caused by frequent hand washing
Authors: Kampf Günter , Ennen Joachim
Published: February 2006

Background

Aim of the study was to determine the effect of the regular use of a hand cream after washing hands on skin hydration and skin roughness.

Methods

Twenty-five subjects washed hands and forearms with a neutral soap four times per day, for 2 minutes each time, for a total of two weeks. One part of them used a hand cream after each hand wash, the others did not (cross over design after a wash out period of two weeks). Skin roughness and skin hydration were determined on the forearms on days 2, 7, 9 and 14. For skin roughness, twelve silicon imprint per subject and time point were taken from the stratum corneum and assessed with a 3D skin analyzer for depth of the skin relief. For skin hydration, five measurements per subject and time point were taken with a corneometer.

Results

Washing hands lead to a gradual increase of skin roughness from 100 (baseline) to a maximum of 108.5 after 9 days. Use of a hand cream after each hand wash entailed a decrease of skin roughness which the lowest means after 2 (94.5) and 14 days (94.8). Skin hydration was gradually decreased after washing hands from 79 (baseline) to 65.5 after 14 days. The hand wash, followed by use of a hand cream, still decreased skin hydration after 2 days (76.1). Over the next 12 days, however, skin hydration did not change significantly (75.6 after 14 days).

Conclusion

Repetitive and frequent hand washing increases skin dryness and roughness. Use of a hand cream immediately after each hand wash can confine both skin dryness and skin roughness. Regular use of skin care preparations should therefore help to prevent both dry and rough skin among healthcare workers in clinical practice.
Utilities of the Post-anesthesia State derived by the Standard Gamble method in surgical patients
Authors: Rashiq Saifudin , Edlund Diane , Dick Bruce D
Published: February 2006

Background

There are no published utilities for the post-anesthesia state obtained by the standard gamble method (SG).

Methods

We obtained utilities for postoperative pain, nausea, vomiting, urinary retention and myalgia from 100 adults prior to elective surgery using SG.

Results

20% of volunteer participants could not demonstrate a satisfactory understanding of the SG process. Median utilities for each adverse effect were all very close to 1.0, and no statistically significant differences were found between them.

Conclusion

Our results suggest that the avoidance of anesthesia related side effects and pain is not viewed by patients prior to surgery as being worthy of the taking of even a miniscule risk of death. This may affect the decision to utilize anesthesia techniques that trade a lower incidence of common side effects for a very low but finite risk of a catastrophic complication.
Quantification of the fractal nature of mycelial aggregation in Aspergillus niger submerged cultures
Authors: Papagianni Maria
Published: February 2006

Background

Fractal geometry estimates have proven useful in studying the growth strategies of fungi in response to different environments on soil or on agar substrates, but their use in mycelia grown submerged is still rare. In the present study, the effects of certain important fermentation parameters, such as the spore inoculum level, phosphate and manganese concentrations in the medium, on mycelial morphology of the citric acid producer Aspergillus niger were determined by fractal geometry. The value of employing fractal geometry to describe mycelial structures was examined in comparison with information from other descriptors including classic morphological parameters derived from image analysis.

Results

Fractal analysis of distinct morphological forms produced by fermentation conditions that influence fungal morphology and acid production, showed that the two fractal dimensions D
BS (box surface dimension) and D
BM (box mass dimension) are very sensitive indexes, capable of describing morphological differences. The two box-counting methods applied (one applied to the whole mass of the mycelial particles and the other applied to their surface only) enabled evaluation of fractal dimensions for mycelial particles in this analysis in the region of D
BS = 1.20–1.70 and D
BM = 1.20–2.70. The global structure of sufficiently branched mycelia was described by a single fractal dimension D, which did not exceed 1.30. Such simple structures are true mass fractals (D
BS = D
BM = D) and they could be young mycelia or dispersed forms of growth produced by very dense spore inocula (108–109 spores/ml) or by addition of manganese in the medium. Mycelial clumps and pellets were effectively discriminated by fractal analysis. Fractal dimension values were plotted together with classic morphological parameters derived from image analysis for comparisons. Their sensitivity to treatment was analogous to the sensitivity of classic morphological parameters suggesting that they could be equally used as morphological descriptors.

Conclusion

Starting from a spore, the mycelium develops as a mass fractal and, depending on culture conditions, it either turns to a surface fractal or remains a mass fractal. Since fractal dimensions give a measure of the degree of complexity and the mass filling properties of an object, it may be possible that a large number of morphological parameters which contribute to the overall complexity of the particles, could be replaced by these indexes effectively.
Canine parvovirus-like particles, a novel nanomaterial for tumor targeting
Authors: Singh Pratik , Destito Giuseppe , Schneemann Anette , Manchester Marianne
Published: February 2006

Specific targeting of tumor cells is an important goal for the design of nanotherapeutics for the treatment of cancer. Recently, viruses have been explored as nano-containers for specific targeting applications, however these systems typically require modification of the virus surface using chemical or genetic means to achieve tumor-specific delivery. Interestingly, there exists a subset of viruses with natural affinity for receptors on tumor cells that could be exploited for nanotechnology applications. For example, the canine parvovirus (CPV) utilizes transferrin receptors (TfRs) for binding and cell entry into canine as well as human cells. TfRs are over-expressed by a variety of tumor cells and are widely being investigated for tumor-targeted drug delivery. We explored whether the natural tropism of CPV to TfRs could be harnessed for targeting tumor cells. Towards this goal, CPV virus-like particles (VLPs) produced by expression of the CPV-VP2 capsid protein in a baculovirus expression system were examined for attachment of small molecules and delivery to tumor cells. Structural modeling suggested that six lysines per VP2 subunit are presumably addressable for bioconjugation on the CPV capsid exterior. Between 45 and 100 of the possible 360 lysines/particle could be routinely derivatized with dye molecules depending on the conjugation conditions. Dye conjugation also demonstrated that the CPV-VLPs could withstand conditions for chemical modification on lysines. Attachment of fluorescent dyes neither impaired binding to the TfRs nor affected internalization of the 26 nm-sized VLPs into several human tumor cell lines. CPV-VLPs therefore exhibit highly favorable characteristics for development as a novel nanomaterial for tumor targeting.
Absence of seroreversion in 80 HAART-treated HIV-1 seropositive patients with at least five-years undetectable plasma HIV-1 viral load
Authors: Cornelissen Marion , Jurriaans Suzanne , Prins Jan M , Bakker Margreet , van der Kuyl Antoinette C
Published: February 2006

Partial or complete seroreversion for HIV-1, or incomplete antibody evolution are relatively rare events that have so far only been described in patients treated with HAART early after virus infection. Whether seroreversion is seen in patients treated effectively with HAART years after their acute infection has not been investigated so far. Therefore we have investigated anti-HIV antibody levels in 80 patients treated with HAART during chronic HIV-1 infection, who had an undetectable HIV-1 plasma viral load for at least five years. In none of the patients we observed seroreversion, and there was also no significant decrease or increase in antibody levels in this group of patients. So, successful HAART treatment during chronic HIV-1 infection does not induce seroreversion.
Thyroid status influence on adiponectin, acylation stimulating protein (ASP) and complement C3 in hyperthyroid and hypothyroid subjects
Authors: Yu Haiying , Yang Yan , Zhang Muxun , Lu Huiling , Zhang Jianhua , Wang Hongwei , Cianflone Katherine
Published: February 2006

Background

Thyroid abnormalities (hyperthyroid and hypothyroid) are accompanied by changes in intermediary metabolism including alterations in body weight, insulin resistance and lipid profile. The aims of this study were to examine plasma ASP, its precursor C3 and adiponectin in hyperthyroid and hypothyroid subjects as compared to controls.

Methods

A total of 99 subjects were recruited from endocrinology/out-patient clinics: 46 hyperthyroid subjects, 23 hypothyroid subjects and 30 control subjects. Subjects were evaluated for FT4, FT3, TSH, glucose, insulin, complete lipid profile and the adipokines: adiponectin, acylation stimulating protein (ASP) and complement C3.

Results

Hyperthyroidism was associated with a 95% increase in adiponectin (p = 0.0002), a 47% decrease in C3 (p < 0.0001), no change in ASP and increased ASP/C3 ratio (p = 0.0012). Hypothyroidism was associated with a 31% increase in ASP (p = 0.008). Adiponectin and C3 correlated with FT3 (r = 0.383, p = 0.004 and r = -0.277, p = 0.007, respectively) and FT4 (r = 0.464, p = 0.003 and r = -0.225, p = 0.03, respectively). ASP correlated with TSH (r = 0.202, p = 0.04). Adiponectin did not correlate with either ASP or C3, only ASP and C3 correlated (r = -0.197, p = 0.05). Adiponectin was negatively correlated with BMI, total cholesterol and plasma triglyceride, while C3 was positively correlated with BMI and total cholesterol. Surprisingly, adiponectin was positively correlated with insulin (r = 0.293, p = 0.02) and HOMA-IR (r = 0.373, p = 0.003) while C3 was negatively correlated with glucose (r = -0.242, p = 0.022, insulin (r = -0.184, p = 0.05) and HOMA-IR.

Conclusion

These changes suggest that thyroid disease may be accompanied by changes in adipokines, which may contribute to the phenotype expressed.
A Model of Plausibility
Authors: Connell Louise , Keane Mark T.
Published: February 2006

Plausibility has been implicated as playing a critical role in many cognitive phenomena from comprehension to problem solving. Yet, across cognitive science, plausibility is usually treated as an operationalized variable or metric rather than being explained or studied in itself. This article describes a new cognitive model of plausibility, the Plausibility Analysis Model (PAM), which is aimed at modeling human plausibility judgment. This model uses commonsense knowledge of concept‐coherence to determine the degree of plausibility of a target scenario. In essence, a highly plausible scenario is one that fits prior knowledge well: with many different sources of corroboration, without complexity of explanation, and with minimal conjecture. A detailed simulation of empirical plausibility findings is reported, which shows a close correspondence between the model and human judgments. In addition, a sensitivity analysis demonstrates that PAM is robust in its operations.
Prolactin Secretion in Mice with Thyrotropin-Releasing Hormone Deficiency
Authors: Yamada Masanobu , Shibusawa Nobuyuki , Ishii Sumiyasu , Horiguchi Kazuhiko , Umezawa Ryohei , Hashimoto Koshi , Monden Tsuyoshi , Satoh Teturo , Hirato Junko , Mori Masatomo
Published: February 2006

The physiological roles of TRH in pituitary lactotrophs, particularly during lactation, remain unclear. We studied the prolactin (PRL) status, including serum PRL and PRL mRNA levels in the pituitary, in nonlactating and lactating TRH-deficient (TRH−/−) mice with a rescue study with thyroid hormone and TRH. We found that, as reported previously for male TRH−/− mice, neither the morphology of the lactotrophs, PRL content in the pituitary, nor the serum PRL concentration was changed in nonlactating female TRH−/− mice. However, concurrent hypothyroidism induced a mild decrease in the PRL mRNA level. In contrast, during lactation, the serum PRL level in TRH−/− mice was significantly reduced to about 60% of the level in wild-type mice, and this was reversed by prolonged TRH administration, but not by thyroid hormone replacement. The PRL content and PRL mRNA level in the mutant pituitary during lactation were significantly lower than those in wild-type mice, and these reductions were reversed completely by TRH administration, but only partially by thyroid hormone replacement. Despite the low PRL levels, TRH−/− dams were fertile, and the nourished pups exhibited normal growth. Furthermore, the morphology of the pituitary was normal, and high performance gel filtration chromatography analysis of the PRL molecule revealed no apparent changes. We concluded that 1) TRH is not essential for pregnancy and lactation, but is required for full function of the lactotrophs, particularly during lactation; and 2) the PRL mRNA level in the pituitary is regulated by TRH, both directly and indirectly via thyroid hormone.
Differential Response of Progesterone Receptor Isoforms in Hormone-Dependent and -Independent Facilitation of Female Sexual Receptivity
Authors: Mani Shaila K. , Reyna Andrea M. , Chen Jian Zhong , Mulac-Jericevic Biserka , Conneely Orla M.
Published: February 2006

Neurobehavioral effects of progesterone are mediated primarily by its interaction with neural progesterone receptors (PRs), expressed as PR-A and PR-B protein isoforms. Whereas the expression of two isoforms in the neural tissues is suggestive of their selective cellular responses and modulation of distinct subsets of PR-induced target genes, the role of individual isoforms in brain and behavior is unknown. We have previously demonstrated a critical role for PRs as transcriptional mediators of progesterone (ligand-dependent), and dopamine (ligand-independent)-facilitated female reproductive behavior in female mice lacking both the isoforms of PR. To further elucidate the selective contribution of the individual PR isoforms in female sexual receptive behavior, we used the recently generated PR-A and PR-B isoform-specific null mutant mice. We present evidence for differential responses of each isoform to progesterone and dopamine agonist, SKF 81297 (SKF), and demonstrate a key role for PR-A isoform in both hormone-dependent and -independent facilitation of sexual receptive behavior. Interestingly, whereas both the isoforms were essential for SKF-facilitated sexual behavior, PR-A appeared to play a more important role in the 8-bromo-cAMP-facilitated lordosis response, raising the possibility of distinct intracellular signaling pathways mediating the responses. Finally, we also demonstrate that antiprogestin, RU38486, was an effective inhibitor of PR-A-mediated, progesterone-dependent, but not SKF or 8-bromo-cAMP-dependent sexual receptivity. The data reveal the selective contributions of individual isoforms to the signaling pathways mediating female reproductive behavior.
The RNA Ontology Consortium: An open invitation to the RNA community
Authors: LEONTIS NEOCLES B. , ALTMAN RUSS B. , BERMAN HELEN M. , BRENNER STEVEN E. , BROWN JAMES W. , ENGELKE DAVID R. , HARVEY STEPHEN C. , HOLBROOK STEPHEN R. , JOSSINET FABRICE , LEWIS SUZANNA E. , MAJOR FRANÇOIS , MATHEWS DAVID H. , RICHARDSON JANE S. , WILLIAMSON JAMES R. , WESTHOF ERIC
Published: February 2006

The aim of the RNA Ontology Consortium (ROC) is to create an integrated conceptual framework—an RNA Ontology (RO)—with a common, dynamic, controlled, and structured vocabulary to describe and characterize RNA sequences, secondary structures, three-dimensional structures, and dynamics pertaining to RNA function. The RO should produce tools for clear communication about RNA structure and function for multiple uses, including the integration of RNA electronic resources into the Semantic Web. These tools should allow the accurate description in computer-interpretable form of the coupling between RNA architecture, function, and evolution. The purposes for creating the RO are, therefore, (1) to integrate sequence and structural databases; (2) to allow different computational tools to interoperate; (3) to create powerful software tools that bring advanced computational methods to the bench scientist; and (4) to facilitate precise searches for all relevant information pertaining to RNA. For example, one initial objective of the ROC is to define, identify, and classify RNA structural motifs described in the literature or appearing in databases and to agree on a computer-interpretable definition for each of these motifs. To achieve these aims, the ROC will foster communication and promote collaboration among RNA scientists by coordinating frequent face-to-face workshops to discuss, debate, and resolve difficult conceptual issues. These meeting opportunities will create new directions at various levels of RNA research. The ROC will work closely with the PDB/NDB structural databases and the Gene, Sequence, and Open Biomedical Ontology Consortia to integrate the RO with existing biological ontologies to extend existing content while maintaining interoperability.
Ab initio crystal structure determination of Bi6Rh12O29 from powder diffraction data
Authors: Stowasser Frank , Renkenberger Christof
Published: February 2006

The complex crystal structure of Bi6Rh12O29 was determined from laboratory X-ray powder diffraction data with the software package TOPAS® [1]. The crystal symmetry is monoclinic (space group C2/m, Z = 4) and the unit cell parameters are a = 19.8510(1) Å, b = 12.24424(6) Å, c = 9.52367(5) Å and β = 97.2890(4)°. The structure is stable at normal pressure and room temperature. There are 4 Bi, 9 Rh and 18 O in the asymmetric unit and totally 188 atoms in the complete unit cell. Rhodium is coordinated by oxygen in slightly distorted edge sharing octahedra which build up crossing sheets both parallel (100) with a distance of d
100/2 and parallel (001) with a distance of d
001. The remaining channels along b contain the bismuth ions in irregular 6- and 8-fold coordination. Because of a small excess of oxygen in the formula – with respect to an expected amount of oxygen indicated by trivalent Bi and also trivalent Rh — the oxidation state of rhodium adjusts to a formal +3.33.
...Plus Shipping and Handling: Revenue (Non) Equivalence in Field Experiments on eBay
Authors: Hossain Tanjim , Morgan John
Published: February 2006

Many firms divide the price a consumer pays for a good into two pieces---the price for the item itself and the price for shipping and handling. With fully rational customers, the exact division between the two prices is irrelevant---only the total price matters. We test this hypothesis by selling matched pairs of CDs and Xbox games in a series of field experiments on eBay. In theory, the ending auction price should vary inversely with the shipping charge to leave the total price paid constant. Contrary to the theory, we find that charging a high shipping cost and starting the auction at a low opening price leads to higher numbers of bidders and higher revenues when the shipping charge is not excessive. We show that these results can be accounted for by boundedly rational bidding behavior such as loss-aversion with separate mental accounts for different attributes of the price or disregard for shipping costs.
Second-Best Climate Agreements and Technology Policy
Authors: Golombek Rolf , Hoel Michael
Published: February 2006

We study second-best climate agreements in the presence of technology spillovers within and across countries, where the technology externalities within each country are corrected through a domestic subsidy of R&D investments. We compare the properties of two types of international climate agreements when the inter-country externalities from R&D are not regulated through the climate agreement. With an international agreement on emission quotas, the equilibrium R&D subsidy is lower than the socially optimal subsidy. The equilibrium subsidy is even lower if the climate agreement instead dictates that a common carbon tax should be imposed in all countries. Under a quota agreement, total quotas should be set low enough for the price of carbon to exceed the Pigovian level, whereas the opposite may be true under a tax agreement. We also show that social costs are higher under a second-best tax agreement than under a second-best quota agreement.
Can Supply Restrictions Lower Price? Violence, Drug Dealing and Positional Advantage
Authors: Caulkins Jonathan P , Reuter Peter , Taylor Lowell J
Published: February 2006

The standard model of markets for illicit drugs predicts that tougher enforcement against sellers will raise prices; yet cocaine and heroin prices have fallen substantially during a period of massive increases in enforcement. We present a model in which the basic mechanisms at work in the textbook model may be substantially altered by an important feature of illegal marketsviolence that creates inheritable heterogeneity along a dimension that both determines relevant production cost and imposes externalities on other suppliers. Dealers frequently make use of violence and threat of violence in the normal course of trade. A seller who is particularly effective in the use of violence may face lower enforcement costs than other dealers and generate an external cost borne by those sellers. Together these features generate a number of counter-intuitive policy implications. For example the arrest of a particularly violent dealer reduces external costs borne by other dealers. The net effect is a possible reduction in costs for the marginal dealer and hence a reduction in price.
Competitive Work Environments and Social Preferences: Field Experimental Evidence from a Japanese Fishing Community
Authors: Carpenter Jeffrey P , Seki Erika
Published: February 2006

Models of job tournaments and competitive workplaces more generally predict that while individual effort may increase as competition intensifies between workers, the incentive for workers to cooperate with each other diminishes. We report on a field experiment conducted with workers from a fishing community in Toyama Bay, Japan. Our participants are employed in three different aspects of fishing. The first group are fishermen, the second group are fish wholesalers (or traders), and the third group are staff at the local fishing coop. Although our participants have much in common (e.g., their common relationship to the local fishery and the fact that they all live in the same community), we argue that they are exposed to different amounts of competition on-the-job and that these differences explain differences in cooperation in our experiment. Specifically, fishermen and traders, who interact in more competitive environments are significantly less cooperative than the coop staff who face little competition on the job. Further, after accounting for the possibility of personality-based selection, perceptions of competition faced on-the-job and the treatment effect of job incentives explain these differences in cooperation to a large extent.
Life-Cycle Consumption and the Age-Adjusted Value of Life
Authors: Kniesner Thomas J , Viscusi W. Kip , Ziliak James P
Published: February 2006

Our research presents new evidence on the age pattern of the implicit value of life revealed from workers' differential wages and job safety pairings. Although aging reduces the number of years of life expectancy, aging can affect the value of life through an effect on planned life-cycle consumption. The elderly could, a priori, have the highest implicit value of life if there is a life-cycle plan to defer consumption until old age. We find that largely due to the age pattern of consumption, which is non-constant, the implicit value of life rises and falls over the lifetime in a way that the value for the elderly is higher than the average over all ages or for the young. There are important health policy implications of our empirical results. Because there may be age-specific benefits of programs to save statistical lives, instead of valuing the lives of the elderly at less than the young, health policymakers should more correctly value the lives of the elderly at as much as twice the young because of relatively greater consumption lost when accidental death occurs.
The Firm's Cost of Capital, Its Effective Marginal Tax Rate, and the Value of the Government's Tax Claim
Authors: Rao Ramesh K. S. , Stevens Eric C
Published: February 2006

This paper develops a theory of the firm's weighted average cost of capital (WACC) and the marginal tax rate with risky debt and potentially redundant depreciation and interest tax shields. The tax shields' risks, the firms borrowing interest rate and its marginal tax rate are intertwined, and they must therefore be determined simultaneously. We capture these interdependencies by determining the borrowing interest rate endogenously, using the single-factor approximate arbitrage pricing theory. This research strategy: a) yields the correct discount rate for valuing the tax shields and shows how better WACC and marginal tax rate estimates can be generated, b) identifies the determinants of the firm's debt capacity in terms of asset characteristics and exogenous economic variables and c) specifies, numerically, how policy variables (corporate tax rate, tax rules, the risk-free rate) affect the market values of claims on the firm's output that are both private (debt, equity) and public (the tax claim).
Do Plants Overcomply with Water Pollution Regulations? The Role of Discharge Variability
Authors: Bandyopadhyay Sushenjit , Horowitz John
Published: February 2006

This paper uses previously unexploited data to examine polluters' compliance with point-source water pollution regulations, a line of inquiry motivated by widespread apparent overcompliance. We use a nationwide panel of monthly plant-level effluent concentrations from 1991-1999. These monthly data allow us to observe month-to-month variability in discharges and therefore to test hypotheses not previously examined.We find that plants that have higher discharge variability have lower median discharges. This is strong evidence for the purported "safety margin" effect. This result then implies that average discharges, a common measure of polluter behavior, are not an accurate indicator of polluter behavior.In response, we construct a plant-specific implied probability of a violation that accounts for discharge variability. We show that plants in richer communities have lower violation probabilities. We further argue that plants are indeed overcomplying with the regulations even when accounting for the safety margin effect.
Legislating from the Oval Office: Why Sam Alito Really Matters
Authors: Silverstein Gordon
Published: February 2006

Samuel Alito and a new breed of conservative jurists may be opening the door to a new version of activism, developing a theory that will provide constitutional justification that breaks down the separation of powers and enabling presidents to more easily legislate from the Oval Office.
Strategic Labeling and Trade of GMOs
Authors: Veyssiere Luc , Giannakas Konstantinos
Published: February 2006

The emergence of agricultural biotechnology and the subsequent introduction of genetically modified organisms (GMOs) into the food system have been among the most controversial issues surrounding the increasingly scrutinized agri-food system. They have received considerable attention in the economics literature with the main focus being on the optimal regulatory response to products of biotechnology. This paper builds on the literature on the regulation of products of biotechnology by placing the analysis of labeling decisions in a multi-country context. Specifically, the objective of this study is to examine the effect of the strategic interdependence between countries on their regulatory responses to products of biotechnology. The paper analyzes the strategic effects of national regulatory decisions on labeling of GM products and identifies the determinants of the non-cooperative Nash equilibrium labeling regimes in a small number of producing countries that supply the world market of an agricultural product. Analytical results show that the Nash equilibrium configuration of labeling regimes in countries that have adopted the GM technology depends on (i) the distribution of consumer preferences and the level of consumer aversion to GM products; (ii) the size of the segregation and labeling costs in these countries; (iii) the relative productive efficiency and the cost effectiveness of the GM technology; (iv) the market power of the life science companies; and (v) the strength of intellectual property rights in these countries.
Ensuring a Safe Food Supply: The Importance of Heterogeneity
Authors: Graff Zivin Joshua S
Published: February 2006

In this paper we develop a model of food safety regulation that considers the employment of a differentiated food market with two types of government certified quality standards: a minimum standard and a higher one. Individuals, heterogeneous in their susceptibility to food-related health risks, choose which safety-grade of food to consume based on price and their vulnerability. The model is then extended to the case where consumers misperceive their susceptibility to health risks associated with food consumption. The theoretical presentation is followed by an application of the model to examine campylobacteriosis and salmonellosis caused by consumption of beef, pork, and chicken. The paper demonstrates that the benefits from multiple quality standards hinges fundamentally on the distribution of vulnerabilities across the population and the associated distribution of population health risks for a given level of food quality. Uniform standards are generally preferred to differentiated ones under either stringent or lax regulations on population health risk. If the population distribution of vulnerabilities is unimodal and consumers misperceive their vulnerability, the value of a differentiated policy will depend on which quality standard is attracting the majority of consumers. The empirical results confirm the importance of the population distribution of vulnerability on the relative desirability of single versus multiple quality standards.
Conflict in the Preceptorship or Field Experience: A Rippling Tide of Silence
Authors: Myrick Florence , Phelan Anne , Barlow Connie , Sawa Russ , Rogers Gayla , Hurlock Debb
Published: February 2006

A major component of the educative process in the professional disciplines is the field education/preceptorship experience in which students are afforded opportunities to develop professional competence under the tutelage of a practising professional and/or a university instructor. During this time students are exposed to competing discourses about what it means to think and act as nurses, teachers, doctors and social workers. Frequently, field teaching is characterized by conflictual situations involving students, field instructors and university faculty. Such conflict is poorly understood as indicated by the lack of literature available in the professional disciplines. The purpose of this study was to explore the phenomenon of conflict within the context of field teaching in professional education. Pivotal to this study was the issue of making sense of the conflict that prospective nurses, teachers, social workers and doctors experience in professional education within the practice realm and how such discourses shape their professional identities, practices and ultimate social values. At issue is the social construction of meaning that takes place within professional education. This study was conducted from the perspective of four professional programs including education, medicine, nursing and social work. The researchers focused on the final year of each program at a time when students were engaged in a major field / preceptorship experience in hospitals, schools, communities and social agencies. The experiences derived from the nursing data are presented in this paper.
The Coming Dollar Decline: A Letter Commenting on "Divergent Views on the Coming Dollar Crisis" by J. Bradford Delong
Authors: Khanna Arun
Published: February 2006

Arun Khanna responds to J. Bradford Delong by arguing that the U.S. dollar has four key strengths that preclude a meltdown in the value of the dollar.
Skills, Ownership, and Economic Security
Authors: Bernanke Ben S
Published: February 2006

Dr. Ben S. Bernanke, the Chairman of the Council of Economic Advisers, and nominee to be Chairman of the Board of Governors of the Federal Reserve System, explains why the "Leave it to Beaver model of economic security is increasingly less viable in today's world," and describes what can be done and what should not.
Economic Crisis or Global Malaise in 2006?
Authors: Stiglitz Joseph
Published: February 2006

Joseph Stiglitz argues that in certain respects the economy is precarious and a crisis is possible, but global malaise is more likely in 2006.
Application of Experimental Stressors in Laboratory Rodents
Authors: Heinrichs Stephen C. , Koob George F.
Published: February 2006

This unit presents eight separate stressor protocols for laboratory rodents. Stress induction is a critical element in the study of neural and neuroendocrine mechanisms involved in establishing and maintaining a state of stress. The first four procedures, immobilization, footshock, swimming, and noise, involve acute exposure to noxious stimuli. The next three procedures, social isolation, resident/intruder aggression, and maternal deprivation, induce social disruption by withdrawal from a group housing condition, attack within the unfamiliar territory of a dominant male, or segregation of a preweanling pup from its mother, respectively. The final procedure, sleep deprivation, involves passive denial of the opportunity to sleep. Support protocols are provided to address the need for environmental acclimation and calming procedures prior to any stress‐related studies (including, for rats, handling of the animals as a calming measure) and to detail a simple method of quantifying the response to a given stressor by direct measurement of levels of the stress hormones adrenocorticotropic hormone (ACTH) and corticosterone.
Overview of Methods for Assessing the Mouse Auditory System
Authors: Willott James F.
Published: February 2006

The three general approaches for assessing the mouse auditory system presented in UNITS here–here are complementary, but differ in the time required for testing as well as the goals of the tests: the auditory brainstem response (ABR; UNIT here), distortion product otoacoustic emissions (DPOAE; UNIT here), and lick suppression behavioral test (UNIT here). Various issues that need to be addressed in the testing of mouse hearing are discussed in this overview, including accurate nomenclature of the strain and/or mutations, environmental versus genetic influences, selection of frequencies to be tested, and appropriate animal care and use.
Behavioral Assessment of Hearing in Mice—Conditioned Suppression
Authors: Heffner Henry E. , Koay Gimseong , Heffner Rickye S.
Published: February 2006

The method of conditioned suppression described in this unit involves training a thirsty mouse to make steady contact with a waterspout in order to receive a slow, but steady trickle of water and then pairing a sound with mild electric shock delivered through the spout. The mouse quickly learns to avoid the shock by breaking contact with the spout whenever it detects the sound. This suppression of drinking is then used to indicate that the animal detected the sound. Because it is a cognitively simple procedure, conditioned suppression can be used to determine the ability of brain‐damaged and genetically altered as well as normal animals to detect and discriminate sounds.