bluuebunny/crossref_metadata_2025 huggingface dataset:
Metabolic Effects of Mental Stress during Over‐ and Underfeeding in Healthy Women
Authors: Seematter Gérald , Dirlewanger Mirjam , Rey Valentine , Schneiter Philippe , Tappy Luc
Published: April 2008

Objective: To assess the short‐term consequences of carbohydrate or fat overfeeding or of food restriction on the metabolic effects of mental stress in healthy lean women.

Research Methods and Procedures: The effects of a sympathetic activation elicited by mental stress were evaluated in a group of healthy women after standardized isocaloric feeding (ISO) or after a 3‐day overfeeding with 40% excess calories as either carbohydrate overfeeding (CHO OF) or fat overfeeding (FAT OF). Oxygen consumption rate (VO2) was measured as an index of energy expenditure, and subcutaneous glycerol concentrations were monitored with microdialysis. The same measurements were performed in another group of healthy women after ISO and after a 3‐day period of underfeeding with a protein sparing modified fast (UF).

Results: In all conditions, mental stress significantly increased heart rate, blood pressure, plasma norepinephrine and epinephrine concentrations, and VO2, and produced a nonsignificant increase in subcutaneous glycerol concentrations. CHO OF and FAT OF did not alter the effects of mental stress on VO2 and subcutaneous glycerol concentrations. In contrast, UF increased basal VO2 but significantly reduced its stimulation by mental stress. UF also enhanced the increase in subcutaneous glycerol concentrations during mental stress.

Discussion: UF reduces the stimulation of energy expenditure and enhances lipolysis during sympathetic activation. These adaptations may be involved in mobilization of endogenous fat while limiting weight loss. In contrast, short‐term overfeeding fails to alter the sympathetic control of energy expenditure and lipolysis.
Effects of Fluoxetine Administration on Neuropeptide Y and Orexins in Obese Zucker Rat Hypothalamus
Authors: Gutiérrez Arantza , Saracíbar Gonzalo , Casis Luis , Echevarría Enrique , Rodríguez Víctor Manuel , Macarulla Maria Teresa , Abecia Luis C. , Portillo María P.
Published: April 2008

Objective: The aim of this work was to study the potential involvement of neuropeptide Y (NPY) and orexins in the anorexigenic mechanism of fluoxetine in obese Zucker rats, assessing the effects of chronic fluoxetine treatment on NPY and orexin immunostaining in several hypothalamic regions.

Research Methods and Procedures: Male obese Zucker (fa/fa) rats were administered fluoxetine (10 mg/kg intraperitoneally) daily for 2 weeks. The control group was administered 0.9% NaCl solution. Carcass composition was assessed using the official methods of the Association of Official Analytical Chemists. To test the potential thermogenic effect of fluoxetine administration, total body oxygen consumption was measured daily for 60 minutes before fluoxetine or saline injection and for 30 minutes after drug or saline injection. Hypothalamic arcuate and paraventricular nuclei, and the lateral hypothalamic area were immunostained for NPY, orexin A, and orexin B. Commercial kits were used for serum determinations.

Results: Chronic fluoxetine administration in obese Zucker rats generated a reduction in body weight gain, food intake, adipocyte size, fat mass, and body protein. A decrease in NPY immunostaining in the paraventricular nucleus, without changes in the arcuate, was observed. However, no changes were observed in the number of neural cells immunostained for orexin A or orexin B in the lateral hypothalamic area.

Discussion: Due to the hyperphagic effect of NPY in the paraventricular nucleus, these results suggest that NPY, but not orexins, could be involved in the anorexigenic effect of fluoxetine in obese Zucker rats.
Effects of Energy Expenditure and Ucp1 on Photoperiod‐Induced Weight Gain in Collared Lemmings
Authors: Powell Charles Stephenson , Blaylock Matthew L. , Wang Ruixue , Hunter Heather L. , Johanning Gary L. , Nagy Tim R.
Published: April 2008

Objective: To determine the role of total energy expenditure (TEE) and its components in the ability of collared lemmings to increase weight in response to a decrease in photoperiod.

Research Methods and Procedures: Energy expenditure was measured by 24‐hour indirect calorimetry concurrent with food‐intake studies. TEE and resting and nonresting energy expenditure (REE and NREE, respectively) were adjusted for body weight by analysis of covariance (ANCOVA). Uncoupling protein 1 (Ucp1) mRNA levels from interscapular brown adipose tissue were determined by Northern blot.

Results: TEE and REE of lemmings exposed to a short photoperiod for 10 days were significantly lower than that of lemmings exposed to a long photoperiod (p < 0.05), whereas NREE was not significantly different (p = 0.44). Ucp1 mRNA levels in interscapular brown adipose tissue were 50% lower in short‐ vs. long‐photoperiod lemmings (p < 0.01). Ucp1 mRNA levels were positively related to REE (r2 = 0.79, p < 0.01). After adjustment of REE for differences in Ucp1 mRNA levels, there was no longer a significant difference attributable to photoperiod treatment (p = 0.54).

Discussion: The results of this study indicate that the increase in body mass that occurs when collared lemmings are exposed to a short photoperiod may be primarily fueled by a decrease in REE and is correlated with a decrease in Ucp1 mRNA levels.
Combining Behavioral and Pharmacological Treatments for Obesity
Authors: Phelan Suzanne , Wadden Thomas A.
Published: April 2008

Weight‐loss medications are currently recommended for use only as an adjunct to diet, exercise, and behavior modification. Little, however, is known about the benefits of combining behavioral and pharmacological therapies or about the mechanisms that would make these combined approaches more effective than either used alone. This article reviews the effects of adding pharmacotherapy (i.e., principally sibutramine and orlistat) to a modest program of lifestyle modification. Studies revealed that the addition of medication typically improved short‐ and long‐term weight loss compared with lifestyle modification alone. The best results, however, were obtained when medications were combined with an intensive, group program of lifestyle modification. The two approaches may have additive effects; behavioral treatment seems to help obese individuals control the external (i.e., food‐related) environment, whereas pharmacotherapy may control the internal environment by reducing hunger, cravings, or nutrient absorption. The article examines possible methods of sequencing behavioral and pharmacological therapies and offers suggestions for future research.
Effects of Obesity on Substrate Utilization during Exercise
Authors: Goodpaster Bret H. , Wolfe Robert R. , Kelley David E.
Published: April 2008

Objective: The capacity for lipid and carbohydrate (CHO) oxidation during exercise is important for energy partitioning and storage. This study examined the effects of obesity on lipid and CHO oxidation during exercise.

Research Methods and Procedures: Seven obese and seven lean [body mass index (BMI), 33 ± 0.8 and 23.7 ± 1.2 kg/m2, respectively] sedentary, middle‐aged men matched for aerobic capacity performed 60 minutes of cycle exercise at similar relative (50% Vo2max) and absolute exercise intensities.

Results: Obese men derived a greater proportion of their energy from fatty‐acid oxidation than lean men (43 ± 5% 31 ± 2%; p = 0.02). Plasma fatty‐acid oxidation determined from recovery of infused [0.15 μmol/kg fat‐free mass (FFM) per minute] [1‐13C]‐palmitate in breath CO2 was similar for obese and lean men (8.4 ± 1.1 and 29 ± 15 μmol/kg FFM per minute). Nonplasma fatty‐acid oxidation, presumably, from intramuscular sources, was 50% higher in obese men than in lean men (10.0 ± 0.6 versus 6.6 ± 0.8 μmol/kg FFM per minute; p < 0.05). Systemic glucose disposal was similar in lean and obese groups (33 ± 8 and 29 ± 15 μmol/kg FFM per minute). However, the estimated rate of glycogen‐oxidation was 50% lower in obese than in lean men (61 ± 12 versus 90 ± 6 μmol/kg FFM per minute; p < 0.05).

Discussion: During moderate exercise, obese sedentary men have increased rates of fatty‐acid oxidation from nonplasma sources and reduced rates of CHO oxidation, particularly muscle glycogen, compared with lean sedentary men.
Weight Loss Increases Soluble Leptin Receptor Levels and the Soluble Receptor Bound Fraction of Leptin
Authors: Laimer Markus , Ebenbichler Christoph F. , Kaser Susanne , Sandhofer Anton , Weiss Helmut , Nehoda Hermann , Aigner Franz , Patsch Josef R.
Published: April 2008

Objective: Soluble leptin receptor (sOB‐R) represents the main binding site for leptin in human blood. The aim of this study was to investigate the relationship between leptin and soluble leptin receptor and the bound/free ratio after pronounced weight reduction.

Research Methods and Procedures: A total of 18 morbidly obese women participated in this prospective study. Subjects were examined for fat mass, leptin, and sOB‐R concentrations before and 1 year after Swedish adjustable gastric banding.

Results: Anthropomorphic measures displayed a significant reduction of body mass index [(42.9 ± 5.6 to 32.9 ± 6.0 kg/m2 (mean ± SD)]. Fat mass decreased from 56.3 ± 9.0 to 33.9 ± 12.5 kg. Plasma leptin concentration decreased from 44.6 ± 18.0 to 20.0 ± 13.1 ng/mL (p < 0.001), whereas the sOB‐R levels increased from 11.1 ± 3.6 to 16.6 ± 6.0 U/mL after weight‐reducing surgery. Thus, the sOB‐R bound fraction of leptin increased from 7% to 33%.

Discussion: This work demonstrates a relationship between weight loss, leptin, and sOB‐R concentrations in vivo. During weight loss, leptin levels decreased, whereas sOB‐R levels and the receptor bound fraction of leptin increased. Thus, sOB‐R may negatively regulate free leptin.
Obesity Affects Myocardial Vasoreactivity and Coronary Flow Response to Insulin
Authors: Sundell Jan , Laine Hanna , Luotolahti Matti , Kalliokoski Kari , Raitakari Olli , Nuutila Pirjo , Knuuti Juhani
Published: April 2008

Objective: Obesity is associated with increased risk for cardiovascular diseases and peripheral endothelial dysfunction. We examined whether myocardial vasoreactivity and coronary‐flow response to insulin stimulation are altered in obesity.

Research Methods and Procedures: Myocardial blood flow was quantitated in 10 obese men (body mass index, 33.6 ± 1.9 kg/m2) and 10 healthy matched non‐obese men (body mass index, 24.2 ± 1.9 kg/m2), using positron emission tomography and oxygen‐15‐labeled water. The measurements were performed basally and during adenosine infusion (140 μg/kg per minute), with or without simultaneous physiological (1 mU/kg per minute) and supraphysiological (5 mU/kg per minute) hyperinsulinemia.

Results: Basal myocardial blood flow was not significantly different between obese and non‐obese subjects. Adenosine‐stimulated flow was blunted in obese (3.2 ± 0.6 mL/g per minute) when compared with non‐obese subjects (4.0 ± 1.1 mL/g per minute, p < 0.05). Simultaneous physiological hyperinsulinemia increased adenosine‐stimulated myocardial flow significantly in both groups (to 4.03 ± 1.24 and 4.85 ± 1.04 mL/g per minute in obese and non‐obese men, respectively; p < 0.05 vs. adenosine). Supraphysiological hyperinsulinemia further enhanced the adenosine‐stimulated flow in non‐obese subjects (to 5.56 ± 0.98 mL/g per minute; p < 0.05) but not in obese subjects.

Discussion: Young obese, healthy men have reduced myocardial vasoreactivity, which may represent an early precursor of future coronary artery disease. Additionally, insulin‐induced enhancement of myocardial blood flow is blunted in obesity. Thus, endothelial dysfunction seems to also characterize myocardial vasculature of obese subjects.
Combining Weight‐Loss Counseling with the Weight Watchers Plan for Obese Breast Cancer Survivors
Authors: Djuric Zora , DiLaura Nora M. , Jenkins Isabella , Darga Linda , Jen Catherine K.‐L. , Mood Darlene , Bradley Ellen , Hryniuk William M.
Published: April 2008

Objective: The objective was to develop effective weight‐loss methods for women who have had breast cancer, because obesity may result in an adverse prognosis.

Research Methods and Procedures: This randomized pilot study tested an individualized approach toward weight loss in obese women who have had a diagnosis of breast cancer. An individualized approach was applied either alone or combined with the commercial Weight Watchers program. Forty‐eight women (body mass index of 30 to 44 kg/m2) were enrolled.

Results: Weight change after 12 months of intervention was as follows (mean ± SD): 0.85 ± 6.0 kg in the control group, −2.6 ± 5.9 kg in the Weight Watchers group, −8.0 ± 5.5 kg in the individualized group, and −9.4 ± 8.6 kg in the comprehensive group that used both individualized counseling and Weight Watchers. Weight loss relative to control was statistically significant in the comprehensive group 3, 6, and 12 months after randomization, whereas weight loss in the individualized group was significant only at 12 months. Weight loss of 10% or more of initial body weight was observed in 6 of 10 women in the comprehensive group at 12 months. In the comprehensive and Weight Watchers–only groups, weight loss was significantly related to frequency of attendance at Weight Watchers meetings, and attendance was more frequent in the comprehensive group.

Discussion: These data indicate that the most weight loss was achieved when the counseling approach combined both Weight Watchers and individualized contacts. This was effective even though most of the individualized contacts were by telephone.
Genetic Variability of Adult Body Mass Index: A Longitudinal Assessment in Framingham Families
Authors: Coady Sean A. , Jaquish Cashell E. , Fabsitz Richard R. , Larson Martin G. , Cupples L. Adrienne , Myers Richard H.
Published: April 2008

Objective: To explore the contribution of genetics to the mean, SD, maximum value, maximum less the mean, and change over time in body mass index (BMI) and the residual of body weight after adjustment for height. BMI is frequently used as a general indicator of obesity because of its ease and reliability in ascertainment. Cross‐sectional twin and family studies have shown a moderate‐to‐substantial genetic component for BMI. However, the contribution of genetics to the long‐term average, variability, or change over time in BMI is less clear.

Research Methods and Procedures: Longitudinal data from the Framingham heart study were used to create pedigrees of age‐matched individuals. Heritability estimates were derived using variance‐decomposition methods on a total of 1051 individuals from 380 extended pedigrees followed for a period of 20 years. All subjects were followed from approximately age 35 to 55 years.

Results: Moderate heritability estimates were found for the mean BMI (h2 = 0.37), maximum BMI (h2 = 0.40), and the mean residual of body weight (h2 = 0.36). Low heritability estimates (h2 ≅ 0.20) were found for the maximum less the mean in BMI and the SDs of BMI and residual of body weight. No additive genetic contribution was found for the average change over time in BMI or the residual of body weight.

Discussion: These findings suggest that there is a significant genetic component for the magnitude of BMI throughout an individual's middle‐adult years; however, little evidence was found for a genetic contribution to the variability or rate of change in an individual's BMI.
Plasma Enterostatin: Identification and Release in Rats in Response to a Meal
Authors: Mei Jie , Sörhede‐Winzell Maria , Erlanson‐Albertsson Charlotte
Published: April 2008

Objective: To discover a possible absorption and/or secretion of enterostatin into the circulating blood, as well as to compare the levels of circulating enterostatin after high‐fat feeding and low‐fat feeding.

Research Methods and Procedures: Using a specific enzyme‐linked immunosorbent assay, plasma enterostatin levels were determined after feeding a high‐fat, a high‐fat/‐sucrose, or a low‐fat meal to Sprague‐Dawley rats deprived of food overnight.

Results: The enterostatin levels were increased by all diets; the response to the high‐fat and the high‐fat/‐sucrose meals was greater in magnitude and duration than that to the low‐fat meal. In addition, enterostatin levels correlated with the intake of dietary fat. Plasma enterostatin levels after high‐fat feeding were found to be similar to those after intravenous administration of exogenous enterostatin known to inhibit high‐fat food intake. Gel chromatography of pooled postprandial plasma extracts followed by high‐performance liquid chromatography analysis showed that plasma enterostatin was identical to synthetic enterostatin. Affinity cross‐linking of plasma proteins with 125I‐enterostatin on sodium dodecyl sulfate‐polyacrylamide gel electrophoresis, followed by autoradiography, revealed a single band with a molecular weight of about 66 kDa, indicating the presence of a potential enterostatin‐binding protein in plasma.

Discussion: The measurements of plasma enterostatin may be a sensitive indicator for the measurement of fat intake.
Effect of Glucose Tolerance Status on PAI‐1 Plasma Levels in Overweight and Obese Subjects
Authors: Pannacciulli Nicola , de Mitrio Vito , Marino Renato , Giorgino Riccardo , de Pergola Giovanni
Published: April 2008

Objective: The aim of our study was to examine whether plasminogen activator inhibitor‐1 (PAI‐1) plasma levels varied as a function of differences in glucose tolerance status independently of body fatness, body‐fat distribution, and insulin sensitivity.

Research Methods and Procedures: Plasma PAI‐1 antigen levels, along with insulin resistance [measured by homeostatic model assessment (HOMAIR)], central fat accumulation, body composition, blood pressure, and fasting concentrations of glucose, insulin, and lipids, were measured in 229 overweight and obese [body mass index (BMI) ≥25 kg/m2) subjects with normal glucose tolerance (NGT) and in 44 age‐ and BMI‐matched subjects with impaired glucose tolerance (IGT).

Results: Plasma PAI‐1 antigen levels were significantly higher in IGT than in NGT subjects. Log PAI‐1 was positively correlated with BMI, HOMAIR, and log insulin, and inversely associated with high‐density lipoprotein‐cholesterol both in IGT and in NGT individuals. On the other hand, log PAI‐1 was positively correlated with waist circumference, fat mass (FM), fat‐free mass, systolic and diastolic blood pressure, and log triglycerides only in the NGT group. After multivariate analyses, the strongest determinants of PAI‐1 levels were BMI, FM, waist circumference, and high‐density lipoprotein cholesterol in the NGT group and only HOMAIR in the IGT cohort.

Discussion: This study demonstrates that PAI‐1 concentrations are higher in IGT than in NGT subjects. Furthermore, we suggest that the influences of total adiposity, central fat, and insulin resistance, main determinants of PAI‐1 concentrations, are different according to the degree of glucose tolerance.
Differences in Resting Metabolic Rate between White and African‐American Young Adults
Authors: Sharp Teresa A. , Bell Melanie L. , Grunwald Gary K. , Schmitz Kathryn H. , Sidney Stephen , Lewis Cora E. , Tolan Kim , Hill James O.
Published: April 2008

Objective: A reported lower resting metabolic rate (RMR) in African‐American women than in white women could explain the higher prevalence of obesity in the former group. Little information is available on RMR in African‐American men.

Research Methods and Procedures: We assessed RMR by indirect calorimetry and body composition by DXA in 395 adults ages 28 to 40 years (100 African‐American men, 95 white men, 94 African‐American women, and 106 white women), recruited from participants in the Coronary Artery Risk Development in Young Adults (CARDIA), Birmingham, Alabama, and Oakland, California, field centers.

Results: Using linear models, fat‐free mass, fat mass, visceral fat, and age were significantly related to RMR, but the usual level of physical activity was not. After adjustment for these variables, mean RMR was significantly higher in whites (1665.07 ± 10.78 kcal/d) than in African Americans (1585.05 ± 11.02 kcal/d) by 80 ± 16 kcal/d (p < 0.0001). The ethnic × gender interaction was not significant (p = 0.9512), indicating that the difference in RMR between African‐American and white subjects was similar for men and women.

Discussion: RMR is ∼5% higher in white than in African‐American participants in CARDIA. The difference was the same for men and women and for lean and obese individuals. The prevalence of obesity is not higher in African‐American men than in white men. Because of these reasons, we believe that RMR differences are unlikely to be a primary explanation for why African‐American women are more prone to obesity than white women.
Managing Dysphagia in the Schools
Authors: McNeilly Lemmietta G. , Sheppard Justine J.
Published: April 2008

Purpose

This prologue introduces the clinical forum, “Managing Dysphagia in the Schools,” and informs the reader of the scope of the included articles.

Method

The contributing authors are introduced and a brief summary is provided for each of the 10 articles that make up the forum.

Conclusion

The articles address a broad range of issues, with specific reference to children with dysphagia in school settings. There are comprehensive reviews of legislation, ethical issues, cultural issues, motor learning, medically fragile conditions, severe neuromuscular impairments, and autism spectrum disorder. In addition, there are systematic observations and research that address a model public school dysphagia program, school-based speech-language pathologists' perceptions of competency, family perceptions of school programs, and a program for implementing transition from tube to oral feeding.
Establishing a Public School Dysphagia Program: A Model for Administration and Service Provision
Authors: Homer Emily M.
Published: April 2008

Purpose

Many school-based speech-language pathologists (SLPs) are hampered in participating in managing children with dysphagia by their school systems' lack of supportive policies and procedures. A need exists to better define the dysphagia-trained SLP’s role and clarify the district’s responsibility. The purpose of this article is to address the critical administrative issues and administrative components surrounding dysphagia in the schools and to offer the SLP some solutions to these problems.

Method

A narrative review of the relevant literature addresses the following questions that are important for administrative planning and implementation of programs for students with dysphagia in the schools: (a) Should school systems assume responsibility for working with students with dysphagia? (b) Why is a system-supported procedure recommended? (c) What service delivery models can a system use to serve students with dysphagia? (d) What components should be included in a dysphagia procedure?

Conclusion

SLPs should be proactive in providing dysphagia services to students in the schools. A procedure that is adopted by a school system for all of its employees to follow will offer direction and guidance. This system-supported procedure may provide assurance that dysphagia services are being provided in a professionally acceptable manner. Ongoing staff development and training is essential. A system can implement dysphagia services using existing staff, when possible, and policies and procedures that have been approved by the system.
Family and Cultural Issues in a School Swallowing and Feeding Program
Authors: Davis-McFarland Elise
Published: April 2008

Purpose

This article presents a rationale for speech-language pathologists (SLPs) to provide culturally competent evaluation, diagnostic, and intervention services for children with oral motor, swallowing, and feeding disorders in school settings. There is also a discussion of how changing American public school demographics necessitate the consideration of cultural issues and family-focused approaches to dysphagia services.

Method

This article provides an overview of cultural, religious, and health beliefs of several ethnic groups, as well as information on the dynamics and requirements of cultural competence and family-focused intervention. Ethnographic interviewing is presented as a culturally sensitive diagnostic method. Information on structuring a culturally relevant individualized educational program process is provided. Guidance in the use of interpreters and translators is also offered.

Conclusion

Attention to cultural and family issues in the diagnosis and treatment of dysphagia in a school setting optimizes the opportunities for successful outcomes and better meets the needs of children and families from culturally/linguistically diverse backgrounds.
Schoolchildren With Dysphagia Associated With Medically Complex Conditions
Authors: Lefton-Greif Maureen A. , Arvedson Joan C.
Published: April 2008

Purpose

This article reviews population trends and general characteristics of children with dysphagia in schools, provides an overview of dysphagia teams and the roles of the speech-language pathologist (SLP) in school and hospital settings, and describes assessment and treatment of swallowing and feeding problems in children with complex medical histories.

Method

A review of the literature of swallowing and feeding problems in young children and population trends for children who are at risk for dysphagia was completed. Two case studies are presented to illustrate the complexities that are common to this population and to provide practical information to maximize the health and education outcomes of children with dysphagia.

Results

SLPs in schools are increasingly evaluating and treating children with dysphagia associated with medically complex conditions. There is a rising incidence in preterm births and the survival of medically fragile children, suggesting that a greater number of children will be at risk for dysphagia in the future. Limited evidence is available to support most therapeutic interventions.

Conclusion

School-based SLPs are uniquely positioned to identify swallowing and feeding problems, evaluate and treat children with dysphagia, participate on dysphagia teams in the school setting, and interact with the medical team.
Addressing Feeding Disorders in Children on the Autism Spectrum in School-Based Settings: Physiological and Behavioral Issues
Authors: Twachtman-Reilly Jennifer , Amaral Sheryl C. , Zebrowski Patrecia P.
Published: April 2008

Purpose

The purposes of this article are to define the nature of feeding difficulties in children with autism spectrum disorder (ASD), identify important components of the assessment and treatment of feeding disorders specific to this population, and delineate specific therapeutic techniques designed to improve assessment and treatment within the school setting.

Method

Literature review and case example are used to define the predominant nature of the feeding difficulties that are experienced by some children on the autism spectrum. Characteristics of this complex disorder that can have an impact on feeding skill and behavior are also identified. These factors are then integrated to create assessment and intervention techniques that can be used in conjunction with traditional feeding approaches to facilitate improvements in eating in this unique population.

Implications

The complex nature of ASD and its many influences on feeding skills and behavior create the need for modification to both assessment and treatment approaches. Additional research is needed to create therapeutic protocols that can be used by school-based speech-language pathologists to effectively assess and treat feeding difficulties that are commonly encountered in children with ASD.
Subterahertz Josephson plasma emission in layered high-TC superconducting tunnel junctions
Authors: Alvarez G. A. , Puzzer T. , Wang X. L. , Lewis R. A. , Freeth C. , Dou S. X.
Published: April 2008

We investigated the emission of subterahertz frequency electromagnetic radiation from high-TC superconducting c-axis NdBa2Cu3O7−δ∕PrBa2Cu3O7−δ∕NdBa2Cu3O7−δ trilayer thin film tunneling junctions when external electric and magnetic fields are applied. The current-voltage characteristics under applied ab-plane magnetic fields H (up 8T) exhibit well defined steps, Vn, such that eVn≈hωp∕(2nπ), where the plasma frequency ωp≈0.4 THz and n=1,2,3,….. These steps may be interpreted using Josephson plasma dynamics. The applied voltage creates oscillating currents via the Josephson coupling energy EJ (EJ=hIJ∕4πe, where IJ is the Josephson current and h is Planck’s constant) and the charge energy EC (EC=e2∕2C, where C is the junction capacitance). Thus the Josephson plasma becomes excited by the tunneling current, with some of the energy being emitted as subterahertz frequency radiation. Our results provide a new insight into a solid-state quantum system with considerable potential for new solid-state terahertz emission sources.
Spin-dependent shot noise in a two-dimensional electron gas modulated by magnetic barriers and Rashba spin-orbit coupling
Authors: Zhu Rui , Guo Yong
Published: April 2008

We investigated the spin-dependent shot noise in a two-dimensional electron gas, which is modulated by a stripe of ferromagnetic metal and a stripe of Schottky metal under the influence of Rashba spin-orbit coupling (SOC). It is found that the shot noise and the Fano factor are strongly spin dependent, and the current and the Rashba SOC can greatly enhance their spin polarization. The minima of the Fano factor approach 1/3, which can be interpreted by the collective contribution of noiseless open channels and Poissonian-noise closed ones in the transmission spectra.
Multiple kinases in the interferon-γ response
Authors: Watling D. , Carmo C. R. , Kerr I. M. , Costa-Pereira A. P.
Published: April 2008

Janus kinases (JAKs) and signal transducers and activators of transcription (STATs) are essential for responses to interferons (IFNs), most cytokines, and some growth factors. JAK/STAT signaling is not, however, sufficient for a full IFN-γ response. Here, a convenient, robust, and quantitative flow cytometry-based kinome-wide siRNA screen has identified nine additional kinases as required for the IFN-γ class II HLA response, seven for an antiviral response, and two for the cytopathic response to encephalomyocarditis virus (EMCV). As one example, inhibition of the IFN-γ response by siRNA to ataxia telangiectasia-mutated (ATM) differentially affects a spectrum of IFN-γ-stimulated mRNAs, with inhibitions being seen as early as 1 h after IFN-γ stimulation. The implication of ATM, with its previously recognized function in chromatin decondensation, in the control of transcription early in the IFN-γ response highlights both a role for ATM in cytokine responses and a possible correlation with the chromatin decondensation recently observed in response to IFN-γ in mammalian cells. This work has, therefore, revealed the simplicity, power, and convenience of quantitative flow cytometry-based siRNA screens, a requirement for ATM and multiple additional kinases in the IFN-γ response and a possible requirement for two of these kinases in the cytopathic response to EMCV.
Keeping up with the Joneses: Students' Perceptions of Academically Dishonest Behavior
Authors: Engler Jennifer N. , Landau Joshua D. , Epstein Maya
Published: April 2008

To understand undergraduate perceptions of academic dishonesty and honor codes, our participants estimated the likelihood that they, their friends, and the average college student would plagiarize or cheat on tests. Undergraduates reported that the average college student was most likely to cheat, their friends would be less likely to cheat, and they themselves would be the least likely to cheat. They did not believe that an honor code would have a large effect on their cheating behaviors, but it would reduce the cheating behaviors of their friends and the average student. We discuss these results in the context of social norms research.
Classic and Modern Propaganda in Documentary Film: Teaching the Psychology of Persuasion
Authors: Simpson Kevin E.
Published: April 2008

Primary source material found in documentary film has the potential to richly inform college teaching. This article describes using 2 historically significant documentary-style films to teach concepts in the psychology of persuasion. Exemplary clips taken from Triumph of the Will (Riefenstahl, 1935) and Fahrenheit 9/11 (Moore, 2004) illustrated theoretical and applied topics typically taught in undergraduate social psychology. Evidence of student learning along with positive student evaluations support the use of this approach as an effective way to teach about concepts and techniques in persuasion and propaganda.
Locking of neoclassical tearing modes by error fields and its stabilization by RF current
Authors: Yu Q. , Günter S.
Published: April 2008

The locking of neoclassical tearing modes (NTMs) by error fields is studied numerically. In the regime with low mode frequency and large plasma viscosity, the required field amplitude for mode locking is found to be proportional to the plasma viscosity and the mode frequency but inversely proportional to the square of the magnetic island width and the Alfven velocity, being similar to that of the classical tearing mode. This indicates that NTMs will be locked to low amplitude error fields in a fusion reactor. The stabilization of NTMs by RF current in the presence of a static helical field is therefore further investigated. The applied helical field allows one to control the location of the island's o-point to be in the RF wave deposition region, to enable the NTM stabilization by RF current after mode locking. When the island is large enough to be locked by a small amplitude helical field in the desired phase, the island is reduced to a smaller width by RF current compared with the case without the helical field. This suggests a possible way to enhance the stabilization of NTMs by RF current.
Identification of a Novel Protein MICS1 that is Involved in Maintenance of Mitochondrial Morphology and Apoptotic Release of Cytochrome c
Authors: Oka Toshihiko , Sayano Tomoko , Tamai Shoko , Yokota Sadaki , Kato Hiroki , Fujii Gen , Mihara Katsuyoshi
Published: April 2008

Mitochondrial morphology dynamically changes in a balance of membrane fusion and fission in response to the environment, cell cycle, and apoptotic stimuli. Here, we report that a novel mitochondrial protein, MICS1, is involved in mitochondrial morphology in specific cristae structures and the apoptotic release of cytochrome c from the mitochondria. MICS1 is an inner membrane protein with a cleavable presequence and multiple transmembrane segments and belongs to the Bi-1 super family. MICS1 down-regulation causes mitochondrial fragmentation and cristae disorganization and stimulates the release of proapoptotic proteins. Expression of the anti-apoptotic protein Bcl-XL does not prevent morphological changes of mitochondria caused by MICS1 down-regulation, indicating that MICS1 plays a role in maintaining mitochondrial morphology separately from the function in apoptotic pathways. MICS1 overproduction induces mitochondrial aggregation and partially inhibits cytochrome c release during apoptosis, regardless of the occurrence of Bax targeting. MICS1 is cross-linked to cytochrome c without disrupting membrane integrity. Thus, MICS1 facilitates the tight association of cytochrome c with the inner membrane. Furthermore, under low-serum condition, the delay in apoptotic release of cytochrome c correlates with MICS1 up-regulation without significant changes in mitochondrial morphology, suggesting that MICS1 individually functions in mitochondrial morphology and cytochrome c release.
URL decay in MEDLINE—a 4-year follow-up study
Authors: Wren Jonathan D.
Published: April 2008

Motivation: Internet-based electronic resources, as given by Uniform Resource Locators (URLs), are being increasingly used in scientific publications but are also becoming inaccessible in a time-dependant manner, a phenomenon documented across disciplines. Initial reports brought attention to the problem, spawning methods of effectively preserving URL content while some journals adopted policies regarding URL publication and begun storing supplementary information on journal websites. Thus, a reexamination of URL growth and decay in the literature is merited to see if the problem has grown or been mitigated by any of these changes.

Results: After the 2003 study, three follow-up studies were conducted in 2004, 2005 and 2007. Unfortunately, no significant change was found in the rate of URL decay among any of the studies. However, only 5% of URLs cited more than twice have decayed versus 20% of URLs cited once or twice. The most common types of lost content were computer programs (43%), followed by scholarly content (38%) and databases (19%). Compared to URLs still available, no lost content type was significantly over- or underrepresented. Searching for 30 of these websites using Google, 11 (37%) were found relocated to different URLs.

Conclusions: URL decay continues unabated, but URLs published by organizations tend to be more stable. Repeated citation of URLs suggests calculation of an electronic impact factor (eIF) would be an objective, quantitative way to measure the impact of Internet-based resources on scientific research.

Contact:  Jonathan-Wren@OMRF.org
Implementation of a regulatory gene network to simulate the TH1/2 differentiation in an agent-based model of hypersensitivity reactions
Authors: Santoni Daniele , Pedicini Marco , Castiglione Filippo
Published: April 2008

Motivation: An unbalanced differentiation of T helper cells from precursor type TH0 to the TH1 or TH2 phenotype in immune responses often leads to a pathological condition. In general, immune reactions biased toward TH1 responses may result in auto-immune diseases, while enhanced TH2 responses may cause allergic reactions. The aim of this work is to integrate a gene network of the TH differentiation in an agent-based model of the hyper-sensitivity reaction. The implementation of such a system introduces a second level of description beyond the mesoscopic level of the inter-cellular interaction of the agent-based model. The intra-cellular level consists in the cell internal dynamics of gene activation and transcription. The gene regulatory network includes genes-related molecules that have been found to be involved in the differentiation process in TH cells.

Results: The simulator reproduces the hallmarks of an IgE-mediated hypersensitive reaction and provides an example of how to combine the mesoscopic level description of immune cells with the microscopic gene-level dynamics.

Availability: The basic version of the simulator of the immune response can be downloaded here: http://www.iac.cnr.it/~filippo/C-ImmSim.html

Contact:  f.castiglione@iac.cnr.it

Supplementary information:  Supplementary data are available at Bioinformatics online.
Analysing georeferenced population genetics data with Geneland: a new algorithm to deal with null alleles and a friendly graphical user interface
Authors: Guillot Gilles , Santos Filipe , Estoup Arnaud
Published: April 2008

Summary: We introduce a new algorithm to account for the presence of null alleles in inferences of populations clusters from individual multilocus genetic data. We show by simulations that the presence of null alleles can affect the accuracy of inferences if not properly accounted for and that our algorithm improve signficantly their accuracy.

Availability: This new algorithm is implemented in the program Geneland. It is freely available under GNU public license as an R package on the Comprehensive R Archive Network. It now includes a fully clickable graphical interface. Informations on how to get the software are available on folk.uio.no/gillesg/Geneland.html

Contact:  gilles.guillot@bio.uio.no

Supplementary information: Details on the simulation study are available from folk.uio.no/gillesg/BioInformatics_Geneland
Geostatistical comparison of two independent video surveys of sea scallop abundance in the Elephant Trunk Closed Area, USA
Authors: Adams Charles F. , Harris Bradley P. , Stokesbury Kevin D. E.
Published: April 2008

Adams, C. F., Harris, B. P., and Stokesbury, K. D. E. 2008. Geostatistical comparison of two independent video surveys of sea scallop abundance in the Elephant Trunk Closed Area, USA. – ICES Journal of Marine Science, 65: 995–1003. Geostatistical prediction at unsampled locations is done by kriging, an interpolation technique that minimizes the error variance. Our goal was to verify the technique by comparing kriged abundance estimates with observed counts from an area containing the highest densities of sea scallop (Placopecten magellanicus) offshore of the northeastern USA. In 2006, two independent video surveys of scallop abundance were made in the Elephant Trunk Closed Area, one using a 5.6 × 5.6-km sampling grid and the other with a 2.2 × 2.2-km sampling grid. We generated kriged surfaces of scallop abundance with the 5.6-km grid data, using different combinations of variograms and theoretical models, then tested the null hypothesis of no difference between the predicted and assumed true values (i.e. the 2.2-km grid data). There were significant differences between predicted and true values for three out of four combinations of variogram–model fits to untransformed data, assuming isotropy. In contrast, there was no significant difference between kriged and true values for any combination of variogram–model fits to log-transformed, detrended, anisotropy-corrected data. Classical and robust variograms performed equally well. Kriging can be used to generate accurate maps of scallop abundance if the assumptions of geostatistics are met.
Can stories change a culture?
Authors: Wortmann Craig
Published: April 2008

Purpose

The paper seeks to identify why we need to get past the bits and bullets – e‐mails, text messaging and PowerPoint presentations – and tell the full story. Story is the most powerful way to change a culture. By identifying with beliefs and behaviors, stories are shown as the lynchpin for social, economic, organizational, and individual change.

Design/methodology/approach

This paper shows how cultural change is driven by stories and provides a process through which leaders can work to drive change within their own organizations using the Story Tools: WinBook, StoryMatrix and Story Coach, eScenes and Scenarios. Together the tools provide the framework for leaders to be more effective and consistent leaders.

Findings

Stories are the most successful way to change a culture. By “adding back” context, stories carry success and failure messages, they allow us to reflect and learn by drawing us in, and finally stories influence us to create the right kinds of behavior.

Practical implications

This paper offers practical tools for leaders to capture and tell stories that enhance their leadership skills, as well as offering insights into changing a company's culture.

Originality/value

The originality of this approach to story lies in the story tools – StoryMatrix, Story Coach, WinBook, eScenes and Scenarios developed by the author and his company WisdomTools. The authors's book, What's Your Story? Using Stories to Ignite Performance and Be More Successful, provides the reader with more in‐depth background on the original Story Tools.
Exploring the differential impact of job satisfaction on employee attendance and conduct
Authors: Zeffane Rachid , Ibrahim Mohamed E. , Al Mehairi Rashid
Published: April 2008

Purpose

The purpose of this paper is to explore the impact of job satisfaction on employee attendance and conduct.

Design/methodology/approach

The approach was to use data from a study on job satisfaction and performance conducted in a utility company operating in the United Arab Emirates. Job satisfaction was measured using the 20‐item MSQ (Minnesota Satisfaction Questionnaire) short form. Performance measures were based on the utility company employee performance rating system.

Findings

Preliminary analysis of the data revealed significant differences on aspects of job satisfaction and performance between the two gender groups (i.e. males vs females). In general, female respondents were less satisfied with various aspects of their jobs and the job context than their male counterparts. Similarly, they tended to be less performing than their male counterparts on a number of job performance criteria. This pattern is indicative of an underlying linkage between satisfaction and performance, particularly in relation to gender groups.

Originality/value

The paper discusses the potential cultural specificities of the results and their implications for future research and management practice with regard to job satisfaction and performance.
A taxonomy of manufacturing strategies in Spanish companies
Authors: Luz Martín‐Peña María , Díaz‐Garrido Eloísa
Published: April 2008

Purpose

The literature on manufacturing strategy has focused on analysis of content and process. Limited attention has been given to the concept of manufacturing strategy in taxonomical terms. The purpose of this study is to highlight a taxonomy of manufacturing strategies in Spanish industrial companies.

Design/methodology/approach

A cluster analysis was performed. The classification variable used was based on competitive priorities relating to cost, quality, flexibility, delivery, service and environmental protection. The sample group consisted of 353 companies, belonging to different sectors.

Findings

Empirical analysis results demonstrate the existence of two manufacturing strategies and significant differences in structure and infrastructure policies but not in performance.

Research limitations/implications

The results of the study are not generalizable, given the nature of the sample. Future studies should consider larger samples, including more countries and contexts.

Practical implications

A taxonomy of manufacturing strategies will serve as a useful mechanism to better understand Spain's manufacturing role and position in European and global economies.

Originality/value

The taxonomy presented contributes to the development and enhancement of operations management theory and demonstrates the current strategic importance of the manufacturing function in Spanish companies.
A modular robotic system for industrial applications
Authors: Acaccia Gabriella , Bruzzone Luca , Razzoli Roberto
Published: April 2008

Purpose

The aim of this paper is the development of a modular robotic system for generic industrial applications, including assembly.

Design/methodology/approach

A library of robotic modules has been designed; they are divided into two categories: link modules, not actuated, and joint modules, actuated; the library is characterized by a relatively low number of elements, but allows the assembly of a wide variety of medium‐size serial robots.

Findings

The prototypes of two joint modules (a revolute joint module and a wrist module) and of some link modules have been realized. The behaviour of several serial robots composed of the designed modules has been assessed by multibody simulation. The results confirm the goodness of the proposed approach.

Research limitations/implications

The two prototype modules are under test in combination with simplified modules. The further steps of the research programme will be the completion of the prototype library, and an experimental campaign on different serial chains.

Practical implications

Modularity allows one to achieve a great variety of robots starting from a small set of modules, in order to match different operative requirements. Moreover, modularity dramatically reduces the time‐to‐repair of the robot and consequently improves its overall availability; this is a fundamental feature for modern industrial enterprises aiming at maximizing the resources availability.

Originality/value

The proposed mechanical design of the revolute joint modules, based on a harmonic drive that connects two bodies in relative rotational motion, is compact and robust. Modularity is not restricted to mechanics: a distributed control system is adopted to make the reconfiguration of the robot easier and quicker.