bluuebunny/crossref_metadata_2025 huggingface dataset:
Preference for green packaging in consumer product choices – Do consumers care?
Authors: Rokka Joonas , Uusitalo Liisa
Published: August 2008

In this paper, consumer environmental choice is studied by analysing the relative importance of green packaging when compared with other relevant product attributes. The empirical study is based on a choice‐based conjoint analysis of preferences for functional drink products of a sample of 330 consumers using these products. Our choice‐based approach on environmental behaviour brings new insights to previous research, which predominantly relies on attitude models. Results indicate that consumers differ in their preferences for packaging, brand, price and convenience of use of daily products. In addition, various distinctive consumer segments can be identified on the market. Contrary to several previous studies, we found that the largest consumer segment, one‐third of consumers, favoured environmentally labelled packaging as the most important criteria in their choice. The findings emphasize the increasing importance of ethical and environmental dimension in product choices. We also propose that the attention in environmental consumer research should be shifted from general attitude studies towards the study of actual product choices.
Label performance and the willingness to pay for Fair Trade coffee: a cross‐national perspective
Authors: Basu Arnab K. , Hicks Robert L.
Published: August 2008

In this paper, we investigate how label information detailing the performance of the Fair Trade labelling programme with respect to coffee affect consumers' willingness to pay in the US and in Germany. We provide respondents (university students in the US and Germany) information regarding the hypothetical benefits of the Fair Trade coffee programme on its intended beneficiaries on the production side [the revenue gains to participating marginal farmers (scope of the programme)] and, using stated preference conjoint methods, test how this performance criterion relates to the willingness to pay for Fair Trade coffee. Our empirical results identify a ‘threshold’ property of performance‐based labels. In effect, the willingness‐to‐pay for performance‐based Fair Trade labelled coffee exhibits an inverted U shape in the sense that the willingness to pay is positively related to the scope of the programme, but only up to a critical level. Thereafter, the willingness to pay declines as the income gains to participating growers increase further. Interestingly, this inverted U property is exhibited by both the US and German respondents with different critical thresholds.
Is the urban Indian consumer ready for clothing with eco‐labels?
Authors: Goswami Paromita
Published: August 2008

India has witnessed rapid strides of development at sustained growth rates of more than 8% and has seen a huge spurt in consumption. Consequently, it has been estimated that the increased consumption may result in the country becoming one of the leading offenders relating to environmental pollution. The textiles industry in India is traditionally one of the worst offenders of pollution, with its small units following outdated technology processes. One opportunity to reduce the environmental impact of clothing industry in India is to concentrate textile production within environmentally certified or eco‐labelled clothing. In the absence of existing research, this study investigates whether the urban Indian population would be interested in clothing with eco‐labels. The results suggest the existence of a segment of consumers who are positively motivated towards eco‐labelled garments. This segment profile is described in terms of demographic and psychographic variables. Managerial implications and future directions are suggested.
A computer literacy skills profile of pharmacists residing in two counties of England
Authors: Thomas Peter , Rutter Paul M.
Published: August 2008

Background:  Pharmacy is an information intensive profession and a pharmacist has to be proficient in health care information management. The advance in information technology and the use of computers to access, retrieve and analyse this information is increasingly important. Yet little is known about pharmacists’ computer literacy or information technology skills.

Objectives:  To gain a better understanding of pharmacists’ basic computer skills and their ability to use standard software.

Methods:  Self‐administered postal survey to 747 registered pharmacists residing in two counties of England.

Results:  A total of 386 (52%) pharmacists responded after two mailings. Most responding pharmacists used computers at work and at home. They believed their basic computing skills to be high, although acknowledged that they were skill deficient in using certain software packages. Internet use at work was low (43%) as too was awareness and use of online medical databases; this was reflected in online medical database training being identified as of greatest need.

Conclusions:  Pharmacists were confident in operating computer systems but identified a training need for particular software applications. Of concern is the limited knowledge they possessed and access they had on medical databases.
The value and impact of information provided through library services for patient care: developing guidance for best practice
Authors: Weightman Alison , Urquhart Christine , Spink Siân , Thomas Rhian ,   on behalf of the National Library for Health Library Services Development Group
Published: August 2008

Introduction:  Previous impact tool‐kits for UK health libraries required updating to reflect recent evidence and changes in library services. The National Knowledge Service funded development of updated guidance.

Methods:  Survey tools were developed based on previous impact studies and a systematic review. The resulting draft questionnaire survey was tested at four sites, and the interview schedule was investigated in a fifth area. A literature search in assia, Google Scholar, intute, lisa, lista, scirus, Social Sciences Citation Index (Web of Knowledge), and the major UK University and National Libraries Catalogue (copac), identified ways to improve response rates. Other expert advice contributed to the guidance.

Results:  The resulting guidance contains evidence‐based advice and a planning pathway for conducting an impact survey as a service audit. The survey tools (critical incident questionnaire and interview schedule) are available online. The evidence‐based advice recommends personalizing the request, assuring confidentiality, and using follow‐up reminders. Questionnaires should be brief, and small incentives, such as a lottery draw should be considered. Bias is minimized if the survey is conducted and analysed by independent researchers.

Conclusion:  The guidance is a starting point for a pragmatic survey to assess the impact of health library services.
Improving health communication Supporting the practice of health communication
Authors: Miranda Giovanna F. , Vercellesi Luisa , Pozzi Edoardo , Bruno Flavia
Published: August 2008

Background:  Health authorities, hospitals, commercial enterprises, and mass media all deliver health and medical communication in different forms. With such a vast amount of biomedical and clinical information available, any action to ensure the spread of clinically relevant news items is welcome.

Objectives:  This paper tries to define a new role for health science librarians in improving medical communication and reporting.

Methods:  Literature relating to the health and medical reporting is analysed to identify major difficulties encountered by health communicators.

Results:  There are two areas where health science librarians can develop new roles in health communication: (i) supporting journalists and health communicators in selecting sources and understanding scientific papers, and (ii) directly translating scientific information into news items, supplying a list of products in this direction (i.e. targeted newsletters, media releases, news items). New skills and competencies needed to cope with the new roles are described in detail in a suggested academic curriculum for health communicators.

Conclusions:  A better understanding of the mass media's needs can provide much needed support in the field of health communication.
A novel approach to enhancing cellular glutathione levels
Authors: Maher Pamela , Lewerenz Jan , Lozano Carles , Torres Josep Lluís
Published: August 2008

GSH and GSH‐associated metabolism provide the major line of defense for the protection of cells from oxidative and other forms of toxic stress. Of the three amino acids that comprise GSH, cysteine is limiting for GSH synthesis. As extracellularly cysteine is readily oxidized to form cystine, cystine transport mechanisms are essential to provide cells with cysteine. Cystine uptake is mediated by system xc−, a Na+‐independent cystine/glutamate antiporter. Inhibition of system xc− by millimolar concentrations of glutamate, a pathway termed oxidative glutamate toxicity, results in GSH depletion and nerve cell death. Recently, we described a series of compounds derived from the conjugation of epicatechin (EC) with cysteine and cysteine derivatives that protected nerve cells in culture from oxidative glutamate toxicity by maintaining GSH levels. In this study, we characterize an additional EC conjugate, cysteamine‐EC, that is 5‐ to 10‐fold more potent than the earlier conjugates. In addition, we show that these EC conjugates maintain GSH levels by enhancing the uptake of cystine into cells through induction of a disulfide exchange reaction, thereby uncoupling the uptake from system xc−. Thus, these novel EC conjugates have the potential to enhance GSH synthesis under a wide variety of forms of toxic stress.
Functional Role of Metaplastic Paneth Cell Defensins in Helicobacter pylori‐Infected Stomach
Authors: Tanabe Hiroki , Sato Tomonobu , Watari Jiro , Maemoto Atsuo , Fijiya Mikihiko , Kono Toru , Ashida Toshifumi , Ayabe Tokiyoshi , Kohgo Yutaka
Published: August 2008

Background and Aims:  Chronic gastritis is caused by Helicobacter pylori infection, and gastritis is classified as inflammation, atrophy, and intestinal metaplasia. Detailed pathologic studies have shown that H. pylori settles on the surface of gastric mucosa, and that it is eliminated from metaplastic mucosa. However, its mechanism of natural protection is not well known.

Methods:  Antimicrobial human enteric defensin expression was determined in the RNA and protein levels. Recombinant enteric defensins were produced with a bacterial expression system and their anti‐H. pylori activities were assessed by bactericidal assay.

Results:  Human enteric defensin (HD)‐5 and HD‐6 were detected in Paneth cells, which are observed in the gastric metaplastic mucosa as well as small intestinal epithelia. HD‐5 protein was coexpressed with trypsin, which is considered to be an activating enzyme of HD‐5. Less H. pylori was observed in the intestinal metaplasia with HD‐5 expressing Paneth cells. The recombinant defensins showed killing activity against H. pylori at a low concentration in vitro.

Conclusions:  The human defensins that are expressed in the metaplastic Paneth cells eliminate H. pylori. Metaplastic change may be a purposive development of the human stomach.
Role ofMDR1gene polymorphisms in gingival overgrowth induced by cyclosporine in transplant patients
Authors: De Iudicibus S. , Castronovo G. , Gigante A. , Stocco G. , Decorti G. , Di Lenarda R. , Bartoli F.
Published: August 2008

Background and Objective: The aim of the present study was to determine the association between genotypes of theMDR1gene, encoding P‐glycoprotein, and gingival overgrowth in transplant patients treated with cyclosporine, and to evaluate the effect of periodontal treatment in these patients.

Material and Methods: Fifty transplant patients receiving therapy with cyclosporine and suffering from gingival overgrowth were subjected to nonsurgical periodontal treatment and received oral hygiene instructions. Hyperplastic index, periodontal probing depths, bleeding and plaque scores were recorded at baseline and after 3 and 6 mo. Patients were dichotomized into two groups: those with a hyperplastic index of < 30% (minimal gingival overgrowth) and those with a hyperplastic index of ≥ 30% (clinically significant gingival overgrowth).MDR1C3435T and G2677T polymorphisms were evaluated in all patients and in 100 controls.

Results: At baseline, 32 patients (64%) had minimal gingival overgrowth and 18 patients (36%) had clinically significant gingival overgrowth. The mutated C3435T genotype was significantly more frequent in the second group (p < 0.019). The significant association between gingival overgrowth and the 3435TT genotype was confirmed by logistic regression analysis (p < 0.031). The differences in hyperplastic index, observed at baseline between patients with the TT genotype and those with the CC/CT genotype disappeared in the second and third evaluation. The mean monthly change of the square root of the gingival overgrowth scores for all patients, assessed using linear models, was significantly different from baseline (−0.17 points per month,p < 0.00001); and this was particularly evident in subjects with renal transplant (−1.62,p < 0.01).

Conclusion: Aetiological periodontal and self‐performed maintenance therapy is effective in reducing gingival overgrowth, particularly in subjects with the 3435TT genotype and in patients with renal transplant.
Improved barrier function observed in cultured skin substitutes developed under anchored conditions
Authors: Barai Namrata D. , Boyce Steven T. , Hoath Steven B. , Visscher Marty O. , Kasting Gerald B.
Published: August 2008

Background/purpose: The current method of producing cultured skin substitutes (CSS) is focused on providing treatments for severe skin wounds/burns. We have developed a modified growth method to make them more suitable for in vitro product‐testing/toxicity‐testing purposes.

Method: CSS grown in Petri dishes were either transferred to Franz diffusion cells on day 5 (modified method) or left in the Petri dish (standard method) and maintained in these environments for the remainder of the growth phase. Mitochondrial metabolism (MTT assay) was measured on days 5, 10 and 14 and histology was studied on days 5, 10 and 14. Barrier function for all tissues was evaluated by transferring them to Franz cells (standard method) and measuring transepidermal water loss (TEWL), 3H2O penetration and 14C‐niacinamide permeability on days 7, 14 and 21.

Results: CSS grown by the standard and modified methods showed comparable cell viability and tissue morphology. Barrier function, however, was markedly improved in CSS grown by the modified method. The average improvement at days 7 and 14 was 1.3‐fold for TEWL, 2.1‐fold for 3H2O penetration and 6.4‐fold for 14C‐niacinamide permeability. The barrier function of CSS grown by the modified method was still significantly lower than that of human cadaver skin tested by the same methods.

Conclusions: CSS developed using the anchored multi‐cell system showed similar cell viability and morphology and improved barrier function compared with CSS produced by the standard Petri dish method, thereby improving its potential as an in vitro skin permeability and toxicity model.
Use of digital photography and image analysis techniques to quantify erythema in health care workers
Authors: Canning Jennifer , Barford Brian , Sullivan David , Wickett Randy , Visscher Marty
Published: August 2008

Background/aims: Nosocomial infections affect up to 26% of ICU patients. Compliance with the required hand hygiene procedures remains low, rarely exceeding 50%, with skin irritation as one of the main reasons for lack of conformity. The aim was to quantify the epidermal barrier effects, particularly erythema, from repetitive exposure to hand hygiene procedures among health care workers (HCWs) using an objective, reliable clinical method that could evaluate the entire hand surface.

Methods: The hand skin of HCWs was evaluated before the initial scrub and at the end of multiple 2–3 days work cycles during spring (n=54) and winter (n=60) trials. The skin condition was measured with live visual skin evaluation (LSG), digital image analysis (DIA) of high‐resolution digital images, and visual perception evaluation (VPS) of image pairs.

Results: The HCWs had significantly higher values of erythema than the non‐HCW control group with all methods. Knuckle erythema increased over the cycle in both seasons. It decreased during recovery in spring and continued to increase during recovery in winter. For the DIA area of excess redness, the quantitative measure of erythema, the decrease over the cycle in spring was significantly different than the increase over the cycle in winter. Minimal changes in area of excess redness occurred during recovery in both seasons. With the VPS, both judges found a decrease in erythema during recovery in spring and an increase during recovery in winter, indicating significant differences for spring vs. winter (P<0.05). No differences in VPS erythema were seen for either product set over the work cycle during spring. Correlations were observed for (1) results for the VPS vs. the LSG method and (2) between excess erythema (μ+σ) from DIA and the VPS erythema scores. Relatively low correlations were found between the DIA and VPS methods, i.e., knuckle μ+σ and VPS erythema.

Conclusions: Significant work cycle effects for spring vs. winter were observed with DIA, while significant effects were found during the recovery period with VPS. DIA produced an objective quantitative measure of erythema that was not limited or influenced by other aspects of skin irritation (e.g., dryness, scaling) or texture encountered in the visual methods of LSG and VPS. The DIA method minimizes the difficulty in differentiating erythema severity. Standardization of image capture and processing allows assessment of skin condition across clinical locations. The VPS is a more reliable way to compare skin condition at different times, i.e. beginning vs. the end of a treatment cycle, because images are viewed simultaneously and can be carefully examined for differences.
Acute salivary gland hypofunction in the duct ligation model in the absence of inflammation
Authors: Correia PN , Carpenter GH , Osailan SM , Paterson KL , Proctor GB
Published: August 2008

Objective:  The commonly associated aetiology of salivary gland inflammation and salivary hypofunction has led to the widely held belief that inflammation causes salivary gland hypofunction. Indeed, our own recent study seemed to support this contention. Here, we tested the hypothesis that, in an acute duct ligation model, eliminating inflammation the submandibular gland would recover normal function.

Materials and methods:  Ligation of the rat submandibular gland excretory duct for 24 h was used to induce inflammation and salivary gland hypofunction. A group of duct ligated rats was compared with a second group given dexamethasone, on the day of duct ligation. Twenty‐four hours later salivary gland function was assessed and salivary glands were collected.

Results:  Histology and myeloperoxidase activity assay revealed a profound decrease in inflammatory cell infiltration of ligated glands from rats given dexamethasone, compared with ligated glands in the absence of dexamethasone. Salivary flow rate evoked by methacholine was decreased (P < 0.01) by approximately 56% (ligated vs control, 79 ± 9 μl min−1 g−1vs 177 ± 11 μl min−1 g−1) and salivary flow from ligated dexamethasone‐treated and ligated glands was similar.

Conclusion:  Despite eliminating the inflammatory reaction in the ligated gland, salivary hypofunction was not reversed, suggesting that other mechanisms must be at work in the ligation‐induced salivary hypofunction.
Microflora in oral ecosystems in subjects with radiation‐induced hyposalivation
Authors: Almståhl A , Wikström M , Fagerberg‐Mohlin B
Published: August 2008

Aim:  To analyse the microbial flora in specific oral sites in 13 dentate subjects, 6–8 months after completed radiation therapy (RT group) and in 13 matched controls.

Material and methods:  The microflora on the tongue, buccal mucosa, vestibulum, supragingival plaque and subgingival region was analysed using duplicate sampling and cultivation technique. A clinical examination was also performed.

Results:  Candida albicans was found in one or more sites in 54% of the RT subjects and in 15% of the controls. In three RT subjects, C. albicans was found at all four sites analysed. An unexpected finding was that enterococci were found in all RT subjects and in high number in 38%. None of the controls harboured enterococci. In supragingival plaque, Lactobacillus spp. were detected in 92% of the RT subjects and the number and proportion of Lactobacillus spp. were extremely high compared with the controls. Mutans streptococci were detected in high numbers in 31% of the RT subjects, while they were not detected in 23%.

Conclusion:  The microbial results explain why some RT subjects have an increased susceptibility to oral diseases and stress that site‐specific microbial analysis is an important diagnostic tool when planning oral health preventive care for RT subjects.
Expression and alterations of the PTEN / AKT / mTOR pathway in ameloblastomas
Authors: Scheper MA , Chaisuparat R , Nikitakis NG , Sauk JJ
Published: August 2008

Objectives:  Recently, an allelic loss of phosphatase and tensin homologue (PTEN) was shown to occur in ameloblastomas. In carcinogenesis, loss of PTEN allows for overactivity of the phosphatidylinositol‐3‐kinase/protein kinase B (PI3K / AKT) pathway inducing an upregulation of mammalian‐target of rapamycin (mTOR) and its downstream effector ribosomal‐subunit‐6 kinase (S6K); allowing for uncontrolled cell proliferation, apoptosis inhibition and cell cycle deregulation.

Methods:  Thirty ameloblastomas and five dental follicles were studied, looking at the immunohistochemical expression of total PTEN and AKT, as well as their phosphorylated (p) active forms, and the downstream effector and indicator of mTOR activity p70 ribosomal‐subunit‐6 kinase (pS6K). Also assessed was the expression of extracellular‐signal‐regulated kinase (ERK), which cross talks with AKT.

Results:  Total PTEN was absent in 33.3% of ameloblastomas, while its stabilized, phosphorylatedser380 / thr382 / thr383 form was absent in 83.3% of tumors. In contrast, AKT was expressed in 83.3% of ameloblastomas, showing high expression of the p‐thr308AKT and p‐ser473 AKT forms in 93.3% and 56.6% of cases, respectively. Further, the mTOR activated pS6Kser240 / 244 was detected in 86.7% of ameloblastomas, while ERK was overexpressed in 70.0% of the cases.

Conclusion:  Immunohistochemical analysis of aberrant signaling in the PI3K/AKT/mTOR pathway in ameloblastomas may represent a valuable tool for elucidating pathogenesis, aggressiveness and selecting optimal therapeutics.
Oral manifestations of eating disorders: a critical review
Authors: Lo Russo L , Campisi G , Di Fede O , Di Liberto C , Panzarella V , Lo Muzio L
Published: August 2008

Background:  Eating disorders (ED) are a group of psychopathological disorders affecting patient relationship with food and her/his own body, which manifests through distorted or chaotic eating behavior; they include anorexia nervosa, bulimia nervosa and ED not otherwise specified and may be burdened with life‐threatening complications.

As oral manifestations of ED can occur in many phases of disease progression, they play a significant role in assessment, characterization and prognosis of ED.

Methods:  Mucosal, dental, and salivary abnormalities associated with ED have been reviewed. Relations between oral menifestations and pathogenesis, management and prognosis of ED have been critically analysed.

Results:  Oral manifestations of ED include a number of signs and symptoms involving oral mucosa, teeth, periodontium, salivary glands and perioral tissues; differences exist between patients with anorexia and bulimia. Oral manifestations of ED are caused by a number of factors including nutritional deficiencies and consequent metabolic impairment, poor personal hygiene, drugs, modified nutritional habits and underlying psychological disturbances.

Conclusion:  Oral manifestations of ED can cause impairment of oral function, oral discomfort and pain, and an overall deterioration of aesthetics and quality of life. Their treatment can contribute to overall patient management and prognosis.
Parental region of birth, socio‐economic status and infants' exposure to second‐hand smoke
Authors: Wallby Thomas , Hjern Anders
Published: August 2008

Aim: To investigate the impact of parental region of birth on the risk of exposure to second‐hand smoke for infants.

Methods: The smoking habits, according to child health records, of parents of 14 431 infants in Uppsala county, Sweden, born during 1997–2001, were investigated with logistic regression in the presence of socio‐economic and demographic confounders from national registers.

Results: Fathers born outside of Sweden smoked more often than Swedish‐born fathers irrespective of region of birth (adjusted odds ratios [ORs] 1.77–3.02). Mothers born in Africa (adjusted OR 0.29, 95% CI 0.15–0.58) and Asia (adjusted OR 0.53, 95% CI 0.40–0.70) smoked less often than Swedish‐born mothers. Single parenthood, low income and mother's age ≤24 years increased the risk for parental smoking.

Conclusion: The present study indicates that the risk of smoking in immigrant parents of infants is influenced by the smoking patterns in the region of birth. Smoke cessation interventions targeting fathers are particularly important in immigrant‐dense neighbourhoods in Sweden.
On buckyonions as an interstellar grain component
Authors: Li Aigen , Chen J. H. , Li M. P. , Shi Q. J. , Wang Y. J.
Published: August 2008

The carrier of the 2175 Å interstellar extinction feature remains unidentified since its first detection over 40 yr ago. In recent years, carbon buckyonions have been proposed as a carrier of this feature, based on the close similarity between the electronic transition spectra of buckyonions and the 2175 Å interstellar feature. We examine this hypothesis by modelling the interstellar extinction with buckyonions as a dust component. It is found that dust models containing buckyonions (in addition to amorphous silicates, polycyclic aromatic hydrocarbon molecules, graphite) can closely reproduce the observed interstellar extinction curve. To further test this hypothesis, we call for experimental measurements and/or theoretical calculations of the infrared vibrational spectra of hydrogenated buckyonions. By comparing the infrared emission spectra predicted for buckyonions vibrationally excited by the interstellar radiation with the observed emission spectra of the diffuse interstellar medium, we will be able to derive (or place an upper limit on) the abundance of interstellar buckyonions.
Membrane Permeability of Acylated Cystatin Depends on the Fatty Acyl Chain Length
Authors: Kočevar Nina , Obermajer Nataša , Kreft Samo
Published: August 2008

Hydrophobization of proteins, such as chemical acylation, has been recognized as an efficient method for improving their membrane permeability. In this research, chicken cystatin, a model protein inhibitor of cysteine proteinases, was acylated with fatty acyl residues of 6–18 carbon atoms. The chemical modification was performed using fatty acyl chloride dispersion in aqueous acetonitrile solution. The reaction products were analyzed by capillary electrophoresis, SDS‐PAGE and isoelectric focusing. In vitro inhibitory activity was determined by N‐benzoyl‐d,l‐arginine‐β‐naphthylamide assay and membrane permeability properties of non‐acylated and acylated cystatin by measuring its efficiency to inhibit intracellular cathepsin B in MCF‐10A neo T cells. The experiments showed that acylated cystatin quickly internalized into the cells and effectively inhibited cathepsin B. In contrast, non‐acylated cystatin did not cause inhibition as it was unable to enter the cell. The permeability enhancement effect was shown to depend on the length of the attached fatty acyl chain as the strongest inhibition was caused by cystatin acylated with stearoyl chloride. In addition, chemical modification did not influence the protein’s immunogenicity.
Frege on Definitions
Authors: Shieh Sanford
Published: August 2008

This article treats three aspects of Frege's discussions of definitions. First, I survey Frege's main criticisms of definitions in mathematics. Second, I consider Frege's apparent change of mind on the legitimacy of contextual definitions and its significance for recent neo‐Fregean logicism. In the remainder of the article I discuss a critical question about the definitions on which Frege's proofs of the laws of arithmetic depend: do the logical structures of the definientia reflect the understanding of arithmetical terms prevailing prior to Frege's analyses? Unless they do, it is unclear how Frege's proofs demonstrate the analyticity of the arithmetic in use before logicism. Yet, especially in late writings, Frege characterizes definitions as arbitrary stipulations of the senses or references of expressions unrelated to pre‐definitional understanding. I conclude by examining some options for conceiving of the status of Frege's logicism in light of this apparent tension, and outline a suggestion for a philosophically fruitful way of resolving this tension.
Protein kinase A modulates A‐type potassium currents of larval zebrafish (Danio rerio) white muscle fibres
Authors: Coutts C. A. , Balt L. N. , Ali D. W.
Published: August 2008

Aims:  Potassium (K+) channels are involved in regulating cell excitability and action potential shape. To our knowledge, very little is known about the modulation of A‐type K+ currents in skeletal muscle fibres. Therefore, we sought to determine whether K+ currents of zebrafish white skeletal muscle were modulated by protein kinase A (PKA).

Methods:  Pharmacology and whole‐cell patch clamp were used to examine A‐type K+ currents and action potentials associated with zebrafish white skeletal muscle fibres.

Results:  Activation of PKA by a combination of forskolin + 3‐isobutyl‐1‐methylxanthine (Fsk + IBMX) decreased the peak current density by ∼60% and altered the inactivation kinetics of A‐type K+ currents. The specific PKA inhibitor H‐89 partially blocked the Fsk + IBMX‐induced reduction in peak current density, but had no effect on the change in decay kinetics. Fsk + IBMX treatment did not shift the activation curve, but it significantly reduced the slope factor of activation. Activation of PKA by Fsk + IBMX resulted in a negative shift in the V50 of inactivation. H‐89 prevented all Fsk + IBMX‐induced changes in the steady‐state properties of K+ currents. Application of Fsk + IBMX increased action potential amplitude, but had no significant effect on action potential threshold, half width or recovery rate, when fibres were depolarized with single pulses, paired pulses or with high‐frequency stimuli.

Conclusion:  PKA modulates the A‐type K+ current in zebrafish skeletal muscle and affects action potential properties. Our results provide new insights into the role of A‐type K+ channels in muscle physiology.
Dynamics of Trace Element Concentration During Development and Excitotoxic Cell Death in the Cerebellum of Lurcher Mutant Mice
Authors: Bäurle Jörg , Kučera Jan , Frischmuth Sabine , Lambertz Manfred , Kranda Karel
Published: August 2008

Elevated concentrations of Zn, Cu and Fe, observed in biopsied or post‐mortem tissue from diseased human brains, have often been considered as some of the major factors in the etiology of excitotoxic neuronal death but without any direct evidence for the causal role of metals. Although elevated metal concentrations that precede or coincide with the onset of neurodegeneration may provide such evidence, the dynamics of metal concentrations during excitotoxic cell death has never been established. Hence, we measured time‐resolved Zn, Cu and Fe concentrations during the course of excitotoxic cell death in the Lurcher (Lc/+) mutant mouse with neutron activation analysis. In the Lc/+ cerebellum, Fe and Zn but not Cu concentrations were substantially lower than in normal cerebellum before the onset of neurodegeneration; then the concentration of all three metals doubled during excitotoxic Purkinje cell (PC) death, before stabilizing at abnormally high levels at the end of cell death progression. The rise in metal concentrations followed the onset and progression of PC loss after a delay of almost a week. This temporal correlation between neurodegenerative progression and metal concentrations indicates that elevated metal concentrations are the consequence of metabolic overload and glial activation during excitotoxicity rather than the primary cause of PC death.
On the Motivational Primacy of the Individual Self: ‘I’ Is Stronger than ‘We’
Authors: Gaertner Lowell , Sedikides Constantine , O'Mara Erin M.
Published: August 2008

The self‐concept is dynamic, with momentary definition shifting from a representation of self as a unique and independent social agent to an undifferentiated and interchangeable group member. Indeed, the individual self and collective self are fundamental components of the self‐concept, with each being important and meaningful to human experience. However, are those selves equally important and meaningful? We review a program of research empirically testing three competing hypotheses that suggests that the motivational core of human experience is (a) the individual self, (b) the collective self, or (c) determined by contextual factors that make a given self momentarily accessible. The research furnished unanimous and consistent evidence that the individual self is the motivationally primary form of self‐definition.
Memantine Protects Against Secondary Neuronal Degeneration in Lateral Geniculate Nucleus and Superior Colliculus after Retinal Damage in Mice
Authors: Ito Yasushi , Nakamura Shinsuke , Tanaka Hirotaka , Shimazawa Masamitsu , Araie Makoto , Hara Hideaki
Published: August 2008

The purpose of this study, on mice, was to determine whether memantine, a glutamate‐receptor antagonist of the N‐methyl‐d‐aspartate (NMDA) subtype, protects against neuronal degeneration in the dorsal lateral geniculate nucleus (dLGN) and superior colliculus (SC) after the induction of retinal damage by intravitreal injection of NMDA.

NMDA (20 mM/2 μl) was injected into the vitreous body of the left eye in mice (day 0). To evaluate the neuroprotective effect of memantine, mice were assigned to one of two memantine‐treated groups: receiving a daily administration of memantine at 30 mg/kg/day, p.o. either from day 0 (administered at 1 h before NMDA injection) to day 90 (pretreated group) or from day 7 to day 90 (post‐treated group).

The pretreated group exhibited significant suppression of the retinal damage induced by intravitreal injection of NMDA and significant prevention of transsynaptic neuronal degeneration in the dLGN and SC on the contralateral side. Although the mice of the post‐treated group displayed no reversion of such retinal damage, they did exhibit protection against neuronal degeneration in the LGN and SC on the contralateral side. These data indicate that memantine can protect against transsynaptic neuronal degeneration in the murine brain (LGN and SC) even if treatment is begun after retinal ganglion cell (RGC) death has started.

Memantine protects against the secondary neuronal degeneration in brain regions in the visual pathway that occurs after retinal damage in mice.
Oxytocin Levels in Social Anxiety Disorder
Authors: Hoge Elizabeth A. , Pollack Mark H. , Kaufman Rebecca E. , Zak Paul J. , Simon Naomi M.
Published: August 2008

Oxytocin is a neuropeptide recently associated with social behavior in animals and humans, but the study of its function in populations with social deficits such as autism, schizophrenia, and social anxiety disorder has only recently begun. We measured plasma oxytocin in 24 patients with Generalized Social Anxiety Disorder (GSAD) and 22 healthy controls using an enzyme‐linked immunosorbent assay. There were no significant differences in oxytocin level (pg/mL) between patients (M = 163.0, SD = 109.4) and controls (M = 145.0, SD = 52.9, z = 0.21, P= 0.8). Within the GSAD sample, however, higher social anxiety symptom severity adjusted for age and gender was associated with higher oxytocin level (R2= 0.21, β= 0.014, SE = 0.006, t = 2.18, P= 0.04). In addition, dissatisfaction with social relationships was associated with higher oxytocin levels (R2= 0.18, β=–0.20, SE = 0.10, t =–2.01, P= 0.05). Our data provide preliminary support for a link between social anxiety severity and plasma oxytocin. These findings may suggest a possible role for oxytocin as a facilitator of social behavior, an effect which may not be fully utilized in individuals with severe social anxiety.
An Investigation Into the Effect of the PCB Motion on the Dynamic Response of MEMS Devices Under Mechanical Shock Loads
Authors: Alsaleem Fadi , Younis Mohammad I. , Miles Ronald
Published: August 2008

We present an investigation into the effect of the motion of a printed circuit board (PCB) on the response of a microelectromechanical system (MEMS) device to shock loads. A two-degrees-of-freedom model is used to model the motion of the PCB and the microstructure, which can be a beam or a plate. The mechanical shock is represented as a single point force impacting the PCB. The effects of the fundamental natural frequency of the PCB, damping, shock pulse duration, electrostatic force, and their interactions are investigated. It is found that neglecting the PCB effect on the modeling of MEMS under shock loads can lead to erroneous predictions of the microstructure motion. Further, contradictory to what is mentioned in literature that a PCB, as a worst-case scenario, transfers the shock pulse to the microstructure without significantly altering its shape or intensity, we show that a poor design of the PCB or the MEMS package may result in severe amplification of the shock effect. This amplification can cause early pull-in instability for MEMS devices employing electrostatic forces.
Thermal Design Methodology for an Embedded Power Electronic Module Using Double-Sided Microchannel Cooling
Authors: Mital Manu , Scott Elaine P.
Published: August 2008

This paper presents a thermal design methodology for an integrated power electronic module (IPEM) using embedded, single-phase, and laminar-flow rectangular microchannels. Three-dimensional packaging of electronic components in a small and compact volume makes thermal management more challenging, but IPEMs also offer the opportunity to extract heat from both the top and the bottom side of the module, enabling double-sided cooling. Although double-sided cooling of IPEMs can be implemented using traditional aluminum heat sinks, microchannels offer much higher heat transfer coefficients and a compact cooling approach that is compatible with the shrinking footprint of electronic packages. The overall goal of this work was to find the optimal microchannel configuration for the IPEM using double-sided cooling by evaluating the effect of channel placement, channel dimensions, and coolant flow rate. It was found that the high thermal conductivity copper of the direct bonded copper (DBC) layer is the most feasible location for the channels. Based on a new analytical heat transfer model developed for microchannels in IPEM structures, several design configurations were proposed in this study that employ the microchannels in the copper layers of the top and bottom DBCs. The designs included multiple parallel channels in copper as well as a single wide microchannel. The analytical model was verified using a finite element model, and the competing design configurations were compared against a commercial cooler. For a typical IPEM structure dissipating on the order of 100W of heat, it was concluded that a single microchannel DBC heat sink is preferable to multiple parallel channels under a double-sided cooling configuration, considering thermal performance, pressure drop and fabrication trade-offs.
A High Precision Experimental Method to Determine Poisson’s Ratios of Encapsulant Gels
Authors: Dillard David A. , Mallick Alok , Ohanehi Donatus C. , Yu Jang-Horng , Lefebvre Didier R.
Published: August 2008

A high precision technique for measuring Poisson’s ratios of elastomers was experimentally implemented. Test fixtures consisted of hollow metal cylinders fitted with matching pairs of pressure sensors at the top and bottom. Evaluation of a preliminary low-pressure fixture led to the development and testing of a high pressure version to investigate potential nonlinearities in the response. A series of elastomeric gels was evaluated by casting them into the cylinders and pressurizing the free end. The pressure at the closed end of the gel was attenuated by the resulting deformation in the gel. The resulting pressure profile obeys equations similar to classical shear lag behavior. Poisson’s ratio was easily calculated from the ratio of the two pressures and the aspect ratio of the gel specimen. A series of seven encapsulant gels was characterized. Consistent results for most gels were obtained to the fifth significant digit, confirming the high precision capabilities of this simple technique. Accurate information on Poisson’s ratio may be required for elastomeric materials that are used in constrained configurations where volumetric changes can be important.
Multidisciplinary Design and Optimization Methodologies in Electronics Packaging: State-of-the-Art Review
Authors: Hadim Hamid , Suwa Tohru
Published: August 2008

Electronics packaging design is a process that requires optimized solutions based on multidisciplinary design trade-offs, which usually have complex relationships among multiple design variables. Required numerical analyses combining electrical, thermal, and thermomechanical, among others, have made the multidisciplinary design and optimization process more challenging because of their time-intensive modeling and computation. In this paper, a state-of-the-art review of recent multidisciplinary design and optimization methodologies in electronics packaging is presented. The reported methodologies are divided into three groups: (1) integrated multidisciplinary computer aided design (CAD) environment, (2) semi-automated design optimization techniques, and (3) automated component placement techniques. In the first group, multidisciplinary design and optimization are carried out using interactive CAD environment software. The electronics packaging designer inputs data and makes decisions, while the CAD software provides a comprehensive multidisciplinary modeling and simulation environment. In the second group, using semi-automated design optimization methodologies, various objectives are optimized simultaneously mainly based on package configurations (dimensions), material properties, and operating conditions. In the third group, optimal placement of heat generating components is performed automatically based on multiple requirements. In recent years, methodologies using (1) detailed numerical analysis models directly connected to optimization algorithms, (2) design of experiments (DoE), and (3) artificial neural networks (ANNs) have been proposed as new trends in this field. These methodologies have led to significant improvement in design optimization capabilities, while they require intensive computational effort. Advantages as well as disadvantages of these methods are discussed.
Optimization of Pin-Fin Heat Sinks in Bypass Flow Using Entropy Generation Minimization Method
Authors: Khan W. A. , Culham J. R. , Yovanovich M. M.
Published: August 2008

An entropy generation minimization method is applied to study the thermodynamic losses caused by heat transfer and pressure drop for the fluid in a cylindrical pin-fin heat sink and bypass flow regions. A general expression for the entropy generation rate is obtained by considering control volumes around the heat sink and bypass regions. The conservation equations for mass and energy with the entropy balance are applied in both regions. Inside the heat sink, analytical/empirical correlations are used for heat transfer coefficients and friction factors, where the reference velocity used in the Reynolds number and the pressure drop is based on the minimum free area available for the fluid flow. In bypass regions theoretical models, based on laws of conservation of mass, momentum, and energy, are used to predict flow velocity and pressure drop. Both in-line and staggered arrangements are studied and their relative performance is compared to the same thermal and hydraulic conditions. A parametric study is also performed to show the effects of bypass on the overall performance of heat sinks.
CHROMOSOME RELATIONSHIPS BETWEEN THE CULTIVATED OAT AVENA SATIVA (6x) AND A. VENTRICOSA (2x)
Authors: Thomas Hugh
Published: August 2008

Chromosome pairing in the F1 hybrid between the cultivated oat Avena sativa and a diploid species A. ventricosa, and in the derived amphiploid, shows that the diploid species is related to one of the genomes of the hexaploid species. The amount of chromosome pairing observed in complex interamphiploid hybrids demonstrates further that A. ventricosa is related to the C. genome of A. sativa. However, the chromosomes of the diploid species have become differentiated from that of the C genome of A. sativa and this is readily apparent in the meiotic behaviour of both the F1 hybrid and the amphiploid.
HUMAN CHROMOSOME MORPHOLOGY. II. STUDIES ON THE SATELLITES AND IDENTIFICATION OF THE LARGE ACROCENTRIC CHROMOSOMES
Authors: Al-Aish Matti S.
Published: August 2008

Chromosome measurements, centromeric position and short arm structure of the three large acrocentric autosomes in the human complement were investigated in somatic metaphases prepared from peripheral blood cultures. Chromosomes 13, 14 and 15 were arranged in descending order of their total length. The results of this study show that chromosome 13 has the lowest arm ratio and possesses a double satellite system, number 14 has the highest arm ratio and lacks satellites, and 15 has intermediate arm ratio and a prominent single satellite.
INHERITANCE IN HEXAPLOID WHEAT OF ADULT-PLANT LEAF RUST RESISTANCE DERIVED FROM AEGILOPS SQUARROSA
Authors: Dyck P. L. , Kerber E. R.
Published: August 2008

The inheritance of adult-plant leaf rust resistance derived from Aegilops squarrosa was studied in a synthetic hexaploid wheat. The hexaploid was produced by combining the AABB component extracted from the common wheat cultivar Canthatch with Ae. squarrosa var. strangulata R.L. 5271 which has adult-plant resistance to several races of leaf rust. Resistance is conferred by a single, partially dominant gene that is inherited independently of Lr12 and L13, two previously identified genes for adult-plant leaf rust resistance. Although monogenic inheritance was observed, this gene must be influenced by the genetic background since its level of resistance was somewhat reduced during successive backcrosses to Thatcher.This new gene for adult-plant leaf rust resistance was linked with each of the genes for foliage waxiness and threshability with a recombination value of 15.6 ± 2.5% and 6.0 ± 1.5%, respectively. The genes for foliage waxiness and threshability were associated with an estimated linkage value of 17.4 ± 2.5%.