bluuebunny/crossref_metadata_2025 huggingface dataset:
ELECTRIC FIELD ENHANCEMENT FACTORS AROUND A METALLIC, END-CAPPED CYLINDER
Authors: PODENOK S. , SVENINGSSON M. , HANSEN K. , CAMPBELL E. E. B.
Published: July 2006

We have calculated the electric field enhancement factor for a metallic cylinder with a hemispherical end-cap in a plane capacitor geometry paying particular attention to the dependence of the field enhancement factor on the anode distance. In addition, we have investigated the angular dependence of the local field at the end-cap. The numerical results, which cover a range of different ratios of cylinder lengths and anode distances, can be fitted with simple functional expressions which provide a useful scaling for calculations of field emission currents from closed cap carbon nanotubes or nanowires.
PLATELET BORON NITRIDE NANOWIRES
Authors: TANG D. M. , LIU C. , CHENG H. M.
Published: July 2006

A novel platelet boron nitride (BN) nanowire was synthesized through a floating catalyst enhanced thermal reaction method by using nickelocene as a catalyst precursor. The nanowires are composed of series-wound cup-like single crystalline hexagonal-BN sections with (0002) planes perpendicular to the nanowire axis direction. A low turn-on electric field of 4.85 V/μm and sound field emission stability were achieved for the BN nanowires. The excellent field emission performance can be attributed to the unique structural characteristics of the platelet BN nanowires.
The Major Histocompatibility Complex, Sexual Selection, and Mate Choice
Authors: Milinski Manfred
Published: July 2006

To maintain sexual reproduction, recombination of good genes through selective mate choice must achieve a twofold genetic benefit in each generation. “Fragrant” immune genes of the major histocompatibility complex (MHC) allow the choosy sex to complement her own set of alleles with a more or less diverse set of male alleles to reach an optimal number of different MHC alleles for the offspring. The optimal complement from the partner should include those MHC alleles that provide resistance against the current parasites, which could be revealed by the expression of costly secondary sexual characters. This maximizes resistance to ever-changing infectious diseases. Because the advantage of sex must be produced through recombination, assortative mating should combine currently advantageous MHC alleles. Preferring just MHC dissimilar mates is only a best-of-bad-job rule. MHC ligand peptides may be the natural “perfume” that reveals a potential partner's MHC genetics probably in all vertebrates. Perfumes may mimick MHC related signals.
Potentiation of insulin-stimulated glucose transport by the AMP-activated protein kinase
Authors: Ju Jeong-Sun , Gitcho Michael A. , Casmaer Carter A. , Patil Pankaj B. , Han Dae-Gyue , Spencer Susan A. , Fisher Jonathan S.
Published: July 2006

Data from the use of activators and inhibitors of the AMP-activated protein kinase (AMPK) suggest that AMPK increases sensitivity of glucose transport to stimulation by insulin in muscle cells. We assayed insulin action after adenoviral (Ad) transduction of constitutively active (CA; a truncated form of AMPKα1) and dominant-negative (DN; which depletes endogenous AMPKα) forms of AMPKα (Ad-AMPKα-CA and Ad-AMPKα-DN, respectively) into C2C12 myotubes. Compared with control (Ad-green fluorescent protein), Ad-AMPK-CA increased the ability of insulin to stimulate glucose transport. The increased insulin action in cells expressing AMPK-CA was suppressed by compound C (an AMPK inhibitor). Exposure of cells to 5-aminoimidazole-4-carboxamide-1β-d-ribofuranoside (an AMPK activator) increased insulin action in uninfected myotubes and myotubes transduced with green fluorescent protein but not in Ad-AMPK-DN-infected myotubes. In Ad-AMPK-CA-transduced cells, serine phosphorylation of insulin receptor substrate 1 was decreased at a mammalian target of rapamycin (or p70 S6 kinase) target site that has been reported to be associated with insulin resistance. These data suggest that, in myotubes, activated AMPKα1 is sufficient to increase insulin action and that the presence of functional AMPKα is required for 5-aminoimidazole-4-carboxamide-1β,d-ribofuranoside-related increases in insulin action.
Regulation of mitochondrial matrix volume
Authors: Kaasik Allen , Safiulina Dzhamilja , Zharkovsky Alexander , Veksler Vladimir
Published: July 2006

Mitochondrial volume homeostasis is a housekeeping cellular function essential for maintaining the structural integrity of the organelle. Changes in mitochondrial volume have been associated with a wide range of important biological functions and pathologies. Mitochondrial matrix volume is controlled by osmotic balance between cytosol and mitochondria. Any dysbalance in the fluxes of the main intracellular ion, potassium, will thus affect the osmotic balance between cytosol and the matrix and promote the water movement between these two compartments. It has been hypothesized that activity of potassium efflux pathways exceeds the potassium influx in functioning mitochondria and that potassium concentration in matrix could be actually lower than in cytoplasm. This hypothesis provides a clear-cut explanation for the mitochondrial swelling observed after mitochondrial depolarization, mitochondrial calcium overload, or opening of permeability transition pore. It should also be noted that the rate of water flux into or out of the mitochondrion is determined not only by the osmotic gradient that acts as the driving force for water transport but also by the water permeability of the inner membrane. Recent data suggest that the mitochondrial inner membrane has also specific water channels, aquaporins, which facilitate water movement between cytoplasm and matrix. This review discusses different phases of mitochondrial swelling and summarizes the potential effects of mitochondrial swelling on cell function.
The role of central vasopressin receptors in the modulation of autonomic cardiovascular controls: a spectral analysis study
Authors: Milutinović Sanja , Murphy David , Japundžić-Žigon Nina
Published: July 2006

Although it has been suggested that vasopressin (VP) acts within the central nervous system to modulate autonomic cardiovascular controls, the mechanisms involved are not understood. Using nonpeptide, selective V1a, V1b, and V2 antagonists, in conscious rats, we assessed the roles of central VP receptors, under basal conditions, after the central application of exogenous VP, and after immobilization, on cardiovascular short-term variability. Equidistant sampling of blood pressure (BP) and heart rate (HR) at 20 Hz allowed direct spectral analysis in very-low frequency (VLF-BP), low-frequency (LF-BP), and high-frequency (HF-BP) blood pressure domains. The effect of VP antagonists and of exogenous VP on body temperature (Tb) was also investigated. Under basal conditions, V1a antagonist increased HF-BP and Tb, and this was prevented by metamizol. V1b antagonist enhanced HF-BP without affecting Tb, and V2 antagonist increased VLF-BP variability which could be prevented by quinapril. Immobilization increased BP, LF-BP, HF-BP, and HF-HR variability. V1a antagonist prevented BP and HR variability changes induced by immobilization and potentiated tachycardia. V1b antagonist prevented BP but not HR variability changes, whereas V2 antagonist had no effect. Exogenous VP increased systolic arterial pressure (SAP) and HF-SAP variability, and this was prevented by V1a and V1b but not V2 antagonist pretreatment. Our results suggest that, under basal conditions, VP, by stimulation of V1a, V1b, and cognate V2 receptors, buffers BP variability, mostly due to thermoregulation. Immobilization and exogenous VP, by stimulation of V1a or V1b, but not V2 receptors, increases BP variability, revealing cardiorespiratory adjustment to stress and respiratory stimulation, respectively.
Role of Persistent Sodium Current in Bursting Activity of Mouse Neocortical Networks In Vitro
Authors: van Drongelen Wim , Koch Henner , Elsen Frank P. , Lee Hyong C. , Mrejeru Ana , Doren Erin , Marcuccilli Charles J. , Hereld Mark , Stevens Rick L. , Ramirez Jan-Marino
Published: July 2006

Most types of electrographic epileptiform activity can be characterized by isolated or repetitive bursts in brain electrical activity. This observation is our motivation to determine mechanisms that underlie bursting behavior of neuronal networks. Here we show that the persistent sodium (NaP) current in mouse neocortical slices is associated with cellular bursting and our data suggest that these cells are capable of driving networks into a bursting state. This conclusion is supported by the following observations. 1) Both low concentrations of tetrodotoxin (TTX) and riluzole reduce and eventually stop network bursting while they simultaneously abolish intrinsic bursting properties and sensitivity levels to electrical stimulation in individual intrinsically bursting cells. 2) The sensitivity levels of regular spiking neurons are not significantly affected by riluzole or TTX at the termination of network bursting. 3) Propagation of cellular bursting in a neuronal network depended on excitatory connectivity and disappeared on bath application of CNQX (20 μM) + CPP (10 μM). 4) Voltage-clamp measurements show that riluzole (20 μM) and very low concentrations of TTX (50 nM) attenuate NaPcurrents in the neural membrane within a 1-min interval after bath application of the drug. 5) Recordings of synaptic activity demonstrate that riluzole at this concentration does not affect synaptic properties. 6) Simulations with a neocortical network model including different types of pyramidal cells, inhibitory interneurons, neurons with and without NaPcurrents, and recurrent excitation confirm the essence of our experimental observations that NaPconductance can be a critical factor sustaining slow population bursting.
Cholinergic Regulation of the Posterior Medial Thalamic Nucleus
Authors: Masri Radi , Trageser Jason C. , Bezdudnaya Tatiana , Li Ying , Keller Asaf
Published: July 2006

We previously showed that the GABAergic nucleus zona incerta (ZI) suppresses vibrissae-evoked responses in the posterior medial (POm) thalamus of the rodent somatosensory system. We proposed that this inhibitory incertothalamic pathway regulates POm responses during different behavioral states. Here we tested the hypothesis that this pathway is modulated by the ascending brain stem cholinergic system, which regulates sleep–wake cycles and states of vigilance. We demonstrate that cholinergic inputs facilitate POm responses to vibrissae stimulation. Activation of the cholinergic system by stimulation of brain stem cholinergic nuclei (laterodorsal tegmental and the pedunculopontine tegmental) or by tail pinch significantly increased the magnitude of POm responses to vibrissae stimulation. Microiontophoresis of the muscarinic receptor agonist carbachol enhanced POm responses to vibrissae stimulation. Application of carbachol to an in vitro slice preparation reduced the frequency but not the amplitude of miniature inhibitory postsynaptic currents, indicating a presynaptic site of action for carbachol. We conclude that the cholinergic system facilitates POm responses by suppressing GABAergic inputs from ZI. We propose the state-dependent gating hypothesis, which asserts that differing behavioral states, regulated by the brain stem cholinergic system, modulate the flow of information through POm.
Physiological Properties of Zebra Finch Ventral Tegmental Area and Substantia Nigra Pars Compacta Neurons
Authors: Gale Samuel D. , Perkel David J.
Published: July 2006

The neurotransmitter dopamine plays important roles in motor control, learning, and motivation in mammals and probably other animals as well. The strong dopaminergic projection to striatal regions and more moderate dopaminergic projections to other regions of the telencephalon predominantly arise from midbrain dopaminergic neurons in the substantia nigra pars compacta (SNc) and ventral tegmental area (VTA). Homologous dopaminergic cell groups in songbirds project anatomically in a manner that may allow dopamine to influence song learning or song production. The electrophysiological properties of SNc and VTA neurons have not previously been studied in birds. Here we used whole cell recordings in brain slices in combination with tyrosine-hydroxylase immunolabeling as a marker of dopaminergic neurons to determine electrophysiological and pharmacological properties of dopaminergic and nondopaminergic neurons in the zebra finch SNc and VTA. Our results show that zebra finch dopaminergic neurons possess physiological properties very similar to those of mammalian dopaminergic neurons, including broad action potentials, calcium- and apamin-sensitive membrane-potential oscillations underlying pacemaker firing, powerful spike-frequency adaptation, and autoinhibition via D2 dopamine receptors. Moreover, the zebra finch SNc and VTA also contain nondopaminergic neurons with similarities (fast-firing, inhibition by the μ-opioid receptor agonist [d-Ala2, N-Me-Phe4, Gly-ol5]-enkephalin (DAMGO)) and differences (strong h-current that contributes to spontaneous firing) compared with GABAergic neurons in the mammalian SNc and VTA. Our results provide insight into the intrinsic membrane properties that regulate the activity of dopaminergic neurons in songbirds and add to strong evidence for anatomical, physiological, and functional similarities between the dopaminergic systems of mammals and birds.
From Placelessness to Place: An Ethnographer's Experience of Growing to Know Places at Sea
Authors: Tyrrell Martina
Published: July 2006

How do we come to know the places we inhabit? What do places mean to us? What associations do we make with them? As an ethnographer and outsider I have grown, in a small way, to know places at sea along the northwest coast of Hudson Bay. In this paper I explore my growth into that knowledge, and how the sea became transformed from a blank space to a place filled with memory and association. I compare my short experience with that of local Inuit, who make use of the sea on a daily basis. Where and how do Inuit learn about places at sea? And how important are those places in their use of and movement through their marine environment?
Water as Country on the Pitjantjatjara Yankunytjatjara Lands South Australia
Authors: Young Diana
Published: July 2006

Anangu, Pitjantjatjara and Yankunytjatjara people living in the north-western areas of South Australia conceptualize changes in the surface of land as evincing the presence of ancestral power. Rain is one such catalyst of change, though it is by no means a certainty on the Pitjantjatjara Yankunytjatjara Lands. When it does appear, water does not stay long on the surface: it is shimmering and unstable. This paper examines the nature of various water sources in contemporary indigenous life, the spatial relationships between earth and sky and the dialectic between life and death that they mediate.
Integrated Tobacco Cessation Counseling in a Diabetes Self-management Training Program
Authors: Hokanson Jennifer M. , Anderson Robyn L. , Hennrikus Deborah J. , Lando Harry A. , Kendall David M.
Published: July 2006

Purpose

The purpose of this study was to evaluate the impact of a tobacco cessation intervention using motivational interviewing on smoking cessation rates during diabetes self-management training (DSMT).

Methods

A randomized controlled trial was conducted with subjects recruited from an ongoing type 2 diabetes adult education program at a large diabetes center. A total of 114 subjects were randomized to intervention (n = 57; face-to-face motivational interviewing plus telephone counseling and offering of medication) or standard care (n = 57). Outcome measures included tobacco cessation rates, mean number of cigarettes smoked, A1C, weight, blood pressure, and lipids.

Results

Intensive intervention using motivational interviewing integrated into a standard DSMT program resulted in a trend toward greater abstinence at 3 months of follow-up in those receiving the intervention. However, this same trend was not observed at 6 months. The addition of this structured smoking cessation intervention did not negatively affect either diabetes education or other measures of diabetes management, including A1C values.
Obesity Management
Authors: Davis Nichola J. , Emerenini Ada , Wylie-Rosett Judith
Published: July 2006

Purpose

The purpose of this study was to assess inner-city clinic patient attitudes about weight loss counseling and to assess practice behaviors of primary care physicians in residency training.

Methods

This is a cross-sectional survey of consecutive patients attending an outpatient internal medicine resident continuity clinic in the Bronx, New York. Participants completed a 30-item questionnaire; a 17-item Quick Weight, Activity & Excess Screener (WAVE); and 13 items to assess patients' attitudes about the physician's role in weight management. A chart review was conducted to ascertain resident practice patterns. Relationships of categorical data were evaluated using χ2 analyses and odds ratios.

Results

Chart reviews (n = 84) indicated that 80% of patients were either obese or overweight; 21% of obese patients and 11% of overweight patients had the diagnosis documented. Of the obese patients (n = 42), 17% had dietitian referrals and 36% had an indication of physician weight loss recommendation. A patient survey indicated that 86% of obese patients wanted to lose weight, 64% wanted a dietitian referral, and 62% felt that their physician could help with weight loss. Obese patients were significantly more likely to receive weight loss recommendations than were overweight patients, but frequency of visits and the diagnosis of diabetes did not increase the likelihood that weight would be addressed.

Conclusions

Physicians need to address how to manage obesity including assessing patient attitudes about making lifestyle changes and using dietitian and other referrals for weight reduction counseling.
Exploring Methods to Extend the Reach of Diabetes Specialist Expertise Into Primary Care Clinics
Authors: King Allen , Wolfe Gary , Healy Susan , Lineham Theresa , Harrison Steve , Ponzio Christina , Armstrong Dana
Published: July 2006

The purpose of this article is to describe a pilot program using centralized diabetes specialist services to guide primary care treatment of diabetes. The program demonstrated the feasibility of disseminating diabetes treatment guidance from a centralized diabetologist clinic. Across all participating sites, approximately 50% of patients achieved HbA1c values of 6.9% or lower. Approximately 80% of all patients participating achieved low-density lipoprotein cholesterol values of 129 mg/dL or lower, and 50% had systolic blood pressure values of 129 mm Hg or lower. Results of the program are promising and deserve further study. Hallmarks of the program include dissemination of diabetes care through midlevel practitioners in primary care offices, using standardized algorithms, and computer-assisted guidance of therapy.
Clinicians Can Help Their Patients Control Postprandial Hyperglycemia as a Means of Reducing Cardiovascular Risk
Authors: Gerich John E.
Published: July 2006

Cardiovascular disease is the leading cause of morbidity and mortality among patients with diabetes. Having diabetes is now recognized as conferring the same risk for cardiovascular disease as hyperlipidemia, hypertension, and smoking. HbA1c levels are the primary indicator of diabetes control and overall glycemic exposure. And recent research has pointed to postprandial hyperglycemia as conferring a greater risk of cardiovascular disease than elevated fasting plasma glucose levels. Unfortunately, clinicians sometimes forget that elevated HbA1c levels can arise from both fasting hyperglycemia and postprandial hyperglycemia. This is particularly important to remember when treating patients whose HbA1c levels may be higher than the desired target while fasting plasma glucose test results are within reference range. This article reviews the evidence supporting the view that postprandial hyperglycemia is a risk factor for cardiovascular disease and therefore should be controlled. Case studies are presented to aid clinicians in helping patients learn how to measure and control their postprandial glucose levels.
Use of a Glucose Algorithm to Direct Diabetes Therapy Improves A1C Outcomes and Defines an Approach to Assess Provider Behavior
Authors: Miller Christopher D. , Ziemer David C. , Kolm Paul , El-Kebbi Imad M. , Cook Curtiss B. , Gallina Daniel L. , Doyle Joyce P. , Barnes Catherine S. , Phillips Lawrence S.
Published: July 2006

Purpose

The purpose of this study was to determine whether an algorithm that recommended individualized changes in therapy would help providers to change therapy appropriately and improve glycemic control in their patients.

Methods

The algorithm recommended specific doses of oral agents and insulin based on a patient's medications and glucose or A1C levels at the time of the visit. The prospective observational study analyzed the effect of the algorithm on treatment decisions and A1C levels in patients with type 2 diabetes.

Results

The study included 1250 patients seen in pairs of initial and follow-up visits during a 7-month baseline and/or a subsequent 7-month algorithm period. The patients had a mean age of 62 years, body mass index of 33 kg/m2, duration of diabetes of 10 years, were 94% African American and 71% female, and had average initial A1C level of 7.7%. When the algorithm was available, providers were 45% more likely to intensify therapy when indicated (P = .005) and increased therapy by a 20% greater amount (P < .001). A1C level at follow-up was 90% more likely to be <7% in the algorithm group, even after adjusting for differences in age, sex, body mass index, race, duration of diabetes and therapy, glucose, and A1C level at the initial visit (P < .001).

Conclusions Use of an algorithm that recommends patient-specific changes in diabetes medications improves both provider behavior and patient A1C levels and should allow quantitative evaluation of provider actions for that provider's patients.
Responsiveness of the International Knee Documentation Committee Subjective Knee Form
Authors: Irrgang James J. , Anderson Allen F. , Boland Arthur L. , Harner Christopher D. , Neyret Philippe , Richmond John C. , Shelbourne K. Donald ,   International Knee Documentation Committee
Published: July 2006

Background and Purpose

The International Knee Documentation Committee Subjective Knee Form was developed to measure change in symptoms, function, and sports activity in patients treated for a variety of knee conditions. Although previous research has demonstrated reliability and validity of the form, its responsiveness has not been evaluated. The purpose of this study was to determine responsiveness of the International Knee Documentation Committee Subjective Knee Form.

Study Design

Cohort study (diagnosis); Level of evidence, 1.

Methods

Patients who participated in the original validation study for the International Knee Documentation Committee Subjective Knee Form completed the form and a 7-level global rating of change scale that ranged from greatly worse to greatly better after a mean of 1.6 years (range, 0.5-2.3 years). Analyses included calculation of the standardized response mean and mean change in International Knee Documentation Committee Subjective Knee Form score compared to the patient's perception of change on the global rating of change scale. In addition, a receiver operating characteristic curve was plotted to determine the change in score that best distinguished patients who improved from those who did not.

Results

The overall standardized response mean was 0.94, which is considered large. With the exception of those who were slightly worse or unchanged, the mean change in the International Knee Documentation Committee Subjective Knee Form score compared to the patients’ perceived global ratings of change was as expected (greatly worse,–15.1; somewhat worse,–8.4; slightly worse, 20.6; no change, 10.7; slightly better, 5.9; somewhat better, 18.1; greatly better, 38.7). The receiver operating characteristic curve analysis revealed that a change score of 11.5 points had the highest sensitivity, and a change score of 20.5 points had the highest specificity to distinguish between those who were or were not improved.

Conclusion

The International Knee Documentation Committee Subjective Knee Form is a responsive measure of symptoms, function, and sports activity for patients with a variety of knee conditions.
Outcome and Structural Integrity after Arthroscopic Rotator Cuff Repair Using 2 Rows of Fixation
Authors: Anderson Kyle , Boothby Michael , Aschenbrener Daniel , Van Holsbeeck Marnix
Published: July 2006

Background

Although arthroscopic repairs of the rotator cuff are becoming increasingly popular, security of fixation remains a concern. Two-row repairs have been described, but clinical outcome reports have primarily involved open techniques.

Hypothesis

An arthroscopic repair technique that uses 2 rows of fixation produces satisfactory outcome and structural integrity by ultrasonography.

Study Design

Case series; Level of evidence, 4.

Methods

Forty-eight patients (52 shoulders) with a full-thickness, but fully reducible, rotator cuff tear who met the inclusion criteria were treated with an arthroscopic rotator cuff repair using 2 rows of suture anchors. The mean tear size was 2.47 cm (range, 1-4 cm). Patients were evaluated by subjective functional assessment (L'Insalata Shoulder Rating Questionnaire), clinical examination, including measured strength testing, and ultrasonography.

Results

At a mean follow-up of 30 months (minimum of 2 years), functional scores improved from a mean of 42 preoperatively to 93 postoperatively (P <. 001). Active range of motion was increased in all measured planes (P <. 001). Strength was also increased in elevation (P <. 001), external rotation (P <. 001), and internal rotation (P =. 033). Nine of the 52 shoulders (17%) had evidence of retear or persistent defect on postoperative ultrasonography. There were no differences detected in functional scores between those with an intact repair and those with a defect, but those with an intact repair were stronger in elevation (P =. 006) and external rotation (P =. 001).

Conclusion

An arthroscopic 2-row rotator cuff repair produces excellent functional outcome and repair integrity comparable with previously reported open repairs. Presence of a defect after repair did not appear to affect patient-reported function and return to preinjury activity but did affect measured strength.
An Allogenic Cell–Based Implant for Meniscal Lesions
Authors: Weinand Christian , Peretti Giuseppe M. , Adams Samuel B. , Bonassar Lawrence J. , Randolph Mark A. , Gill Thomas J.
Published: July 2006

Background

Meniscal tears in the avascular zones do not heal. Although tissue-engineering approaches using cells seeded onto scaffolds could expand the indication for meniscal repair, harvesting autologous cells could cause additional trauma to the patient. Allogenic cells, however, could provide an unlimited amount of cells.

Hypothesis

Allogenic cells from 2 anatomical sources can repair lesions in the avascular region of the meniscus.

Study Design

Controlled laboratory study.

Methods

Both autologous and allogenic chondrocytes were seeded onto a Vicryl mesh scaffold and sutured into a bucket-handle lesion created in the medial menisci of 17 swine. Controls consisted of 3 swine knees treated with unseeded implants and controls from a previous experiment in which 4 swine were treated with suture only and 4 with no treatment. Menisci were harvested after 12 weeks and evaluated histologically for new tissue and percentage of interface healing surface; they were also evaluated statistically.

Results

The lesions were closed in 15 of 17 menisci. None of the control samples demonstrated healing. Histologic analysis of sequential cuts through the lesion showed formation of new scar-like tissue in all experimental samples. One of 8 menisci was completely healed in the allogenic group and 2 of 9 in the autologous group; the remaining samples were partially healed in both groups. No statistically significant differences in the percentage of healing were observed between the autologous and allogenic cell-based implants.

Conclusion

Use of autologous and allogenic chondrocytes delivered via a biodegradable mesh enhanced healing of avascular meniscal lesions.

Clinical Relevance

This study demonstrates the potential of a tissue-engineered cellular repair of the meniscus using autologous and allogenic chondrocytes.
Researching researchers: lessons for research ethics
Authors: Wiles Rose , Charles Vikki , Crow Graham , Heath Sue
Published: July 2006

There is widespread debate about ethical practice in social research with most social researchers arguing that situational relativist approaches are appropriate for resolving the ethical issues that emerge. In this article, we draw on research conducted on an ESRC-funded study of informed consent in social research to explore the ethical issues that are raised when conducting research with one’s peers. The study involved conducting focus groups and telephone interviews with academic and non-academic researchers. The ethical issues emerging from the study related to consent, data ownership and the management of confidentiality and anonymity. Participants’ responses to these issues and the ways that we managed them are discussed. We conclude by exploring the implications of this study for research more generally and argue that the increased regulation of research needs to enable researchers to attend reflexively to the social context in which consent takes place.
Expressions of personhood in Alzheimer’s: moving from ethnographic text to performing ethnography
Authors: Kontos Pia C. , Naglie Gary
Published: July 2006

This article discusses the translation of ethnographic research on embodied selfhood in Alzheimer’s disease into a dramatic production for nurses and ancillary health care professionals working with persons who are cognitively impaired. The appeal of dramatic performance as an alternative medium for the translation and dissemination of research is that it provides an accessible presentation of research to audiences of diverse disciplinary backgrounds, it recovers the experiential immediacy of the body present in the original data-gathering setting, and it can foster critical awareness and engage audiences to envision new possibilities. It is our contention that Expressions of Personhood in Alzheimer’s is an ethnodramatic production that will bring to fruition all of these strengths of the performance paradigm.
Validity in qualitative research revisited
Authors: Cho Jeasik , Trent Allen
Published: July 2006

Concerns with the issues of validity in qualitative research have dramatically increased. Traditionally, validity in qualitative research involved determining the degree to which researchers’ claims about knowledge corresponded to the reality (or research participants’ construction of reality) being studied. The authors note that recent trends have shown the emergence of two quite different approaches to the validity question within the literature on qualitative research. The authors categorize and label these ‘transactional’ validity and ‘transformational’ validity. While useful, the authors assert that neither approach is sufficient to meet the current needs of the field. The authors propose a recursive, process-oriented view of validity as an alternative framework.
Graphic elicitation: using research diagrams as interview stimuli
Authors: Crilly Nathan , Blackwell Alan F. , Clarkson P. John
Published: July 2006

Diagrams are effective instruments of thought and a valuable tool in conveying those thoughts to others. As such, they can be usefully employed as representations of a research domain and act as stimulus materials in interviews. This process of graphic elicitation may encourage contributions from interviewees that are difficult to obtain by other means. By representing concepts and relationships that other visual artefacts cannot depict, diagrams provide a complementary addition to conventional interview stimuli. This article discusses the application of graphic elicitation within the broader context of the diagramming process. Consideration is given to the unique characteristics of diagrams and the ways in which they are interpreted. Thus, the specific benefits that diagrams offer as interview stimuli may be understood. Following this, an example study is described in which the graphic elicitation process was employed in interviews with industrial designers. Reporting on a study in which the interviewees possessed a well-developed graphic sensibility allows a broad range of graphic elicitation’s potential benefits to be illustrated. In closing the article, a discussion is held on the range of methodological issues that must be addressed when employing diagrams in a research study.
Determination of Moisture Diffusivity using the Time Domain Reflectometry (TDR) Method
Authors: Pavlík Zbyšek , Jiřičková Milena , Černý Robert , Sobczuk Henryk , Suchorab Zbigniew
Published: July 2006

The time domain reflectometry (TDR) method is commonly used for the measurement of moisture content in soil science. In this study, the method is employed for the measurement of moisture profiles in building materials. The practical applications of the method are presented on an example of water penetration into cellular concrete (aerated autoclaved concrete) samples. The measured results are then used for the determination of moisture diffusivity as a function of moisture content.
Temperature Stability of Traditional and Low-cost Modern Housing in the Eastern Cape, South Africa
Authors: Makaka Golden , Meyer Edson
Published: July 2006

The aim of this study is to compare the thermal comfort of traditional (Xhosa) huts and low-cost modern houses built under the reconstruction development program (RDP) and the influence of fly ash on brick properties and the indoor environment. A mixing proportion of 50% fly ash produces a brick with lower thermal conductivity and water absorption but with a higher compressive strength, while the clay plasticity decreases with the increase in fly ash. The results indicate that traditional huts offer better thermal comfort than low-cost modern houses, while the fly ash brick house (FABH) has a better thermal performance than the RDP house.
Securitising Suburbia: The Transformation of Anglo-American Mortgage Finance
Authors: Langley Paul
Published: July 2006

Informed by and contributing to approaches to finance that draw on Foucault and actor-network theory, the paper focuses on the contemporary transformation of Anglo-American mortgage finance. This transformation is understood to entail the lengthening of mortgage networks and their increased interconnection with the multiple networks of the capital markets; the making of suburban subjects as property investors in order to produce and extend mortgage borrowing in a booming housing market; and, in particular, the constitution of mortgage-backed securitisation (MBS) techniques through the calculative tools of off-balance sheet accounting, asset management, and credit rating. MBS is the practice of ‘bundling’ together a stream of future obligations arising from mortgagors repayments to provide the basis for the issue of, and the payment of principal and interest on, securities.
Effect of cement composition on corrosion behaviour of galvanised tubes
Authors: Rout T. K. , Srinivas P.
Published: July 2006

In order to understand the phenomenon of corrosion of galvanised tubes for plumbing applications, a study has been undertaken in the laboratory by treating five sets of galvanised tubes in varying cement compositions prepared synthetically for a period of over 45 days. Correlations have been drawn as to the optimal performance of the tubes with respect to the mineralogical phases of the cement.
Microstructure and element distribution in thin MgO coatings on pure magnesium by microarc oxidation
Authors: Dong Q. , Chen C. Z. , Wang D. G. , Ji Q. M.
Published: July 2006

A ceramic like coating was deposited on the substrate of pure magnesium by microarc oxidation. X-ray diffraction, scanning electron microscopy and energy dispersive spectrometry were used to analyse the structure and composition of the coating. X-ray diffraction showed that the phases present in the coating were mainly MgO with some Mg(OH)2. Energy dispersive spectrometry indicated that silicon could be absorbed into the coating in the microarc oxidation process. Scanning electron microscopy showed that the coating surface possessed a porous microstructure, and the pore size was in the range of 1–3 μm. The coating matrix was relatively dense and had a homogeneous thickness. The hardness of the MgO coating could reach 530 HV(0·025 g) and was ∼10 times higher than that of the substrate.
Morphology of Au nanoparticles formed by magnetron sputtering: Ellipsoids and rings
Authors: Chattopadhyay S. , Sarkar S. , Datta A. , Chakraborty P.
Published: July 2006

Ultraviolet (UV) visible spectroscopy, atomic force microscopy and grazing incidence X-ray reflectivity have been used to study morphology of Au nanoparticles grown by direct current (DC) magnetron sputter deposition on hard (glass) and soft amorphous (polystyrene films on quartz) substrates. Au nanoparticles are found to be ellipsoidal showing an increase in ellipticity ϵ [≡ a/ b, a( b)=semimajor (semiminor) axis] with decrease in polystyrene film thickness from 250 to 20 nm, where b remains almost invariant around 3 nm. They sit on top of the film with the semimajor axes roughly parallel to film surface. On glass, the Au film was probed at different stages of growth. After an initial period (1 min) of spheroid nanoparticle formation by dewetting, the coverage was complete (as observed from Au optical spectra) and partially wetting islands appeared after 2 min on the Au covered glass surface. After 5 min, these islands formed rings resembling quantum rings. The rings broke up again into islands after 10 min.
Surface modification of martensitic stainless steels by laser marking and its consequences regarding corrosion resistance
Authors: Steyer P. , Valette S. , Forest B. , Millet J.-P. , Donnet C. , Audouard E.
Published: July 2006

Marking is of prime importance in the field of biomaterials to allow the identification of surgical tools or implants. Markings are obtained under industrial conditions with a pulsed Nd:YAG laser on a X30C13 martensitic stainless steel. Depending on laser parameters, two modes of marking are considered: a surface oxidisation mode and a matter photoablation mode. Electrochemical behaviour, i.e. passive state, corrosion rate, resistance to pitting, is evaluated in Ringer's saline solution. Results are then explained on the basis of metallurgical modifications regarding the phases composition and the distribution of alloying elements. In oxidative regime, laser treatment drastically affects both microstructure and chemical composition. Specially, chromium depletion is measured in subsurface, leading to a loss of passive ability. In ablative mode the surface is transformed into a thin favourable layer of austenite. Moreover, the overall chromium distribution is little modified. Therefore, the passive character is maintained, but with nevertheless a shorter passive domain than base material one.
Parental understanding of wheeze and its impact on asthma prevalence estimates
Authors: Michel G. , Silverman M. , Strippoli M-P. F. , Zwahlen M. , Brooke A. M. , Grigg J. , Kuehni C. E.
Published: July 2006

The epidemiology of wheeze in children, when assessed by questionnaires, is dependent on parents' understanding of the term “wheeze”.

In a questionnaire survey of a random population sample of 4,236 children aged 6–10 yrs, parents' definition of wheeze was assessed. Predictors of a correct definition were determined and the potential impact of incorrect answers on prevalence estimates from the survey was assessed.

Current wheeze was reported by 13.2% of children. Overall, 83.5% of parents correctly identified “whistling or squeaking” as the definition of wheeze; the proportion was higher for parents reporting wheezy children (90.4%). Frequent attacks of reported wheeze (adjusted odds ratio (OR) 3.0), maternal history of asthma (OR 1.5) and maternal education (OR 1.5) were significantly associated with a correct answer, while the converse was found for South Asian ethnicity (OR 0.6), first language not English (OR 0.6) and living in a deprived neighbourhood (OR 0.6).

In summary, the present study showed that misunderstanding could lead to an important bias in assessing the prevalence of wheeze, resulting in an underestimation in children from South Asian and deprived family backgrounds. Prevalence estimates for the most severe categories of wheeze might be less affected by this bias and questionnaire surveys on wheeze should incorporate measures of parents' understanding of the term wheeze.
Airway dimensions measured from micro-computed tomography and high-resolution computed tomography
Authors: Dame Carroll J. R. , Chandra A. , Jones A. S. , Berend N. , Magnussen J. S. , King G. G.
Published: July 2006

Volume averaging results in both over- and underestimation of airway dimensions when they are measured by high-resolution computed tomography (HRCT). The current authors calibrated computerised measurements of airway dimensions from HRCT against a novel three-dimensional micro-computed tomography (CT) standard, which has a 50-fold greater resolution, as well as against traditional morphometry.

Inflation-fixed porcine lung cubes were scanned by HRCT and micro-CT. A total of 59 lumen area (Ai), 30 wall area (Aaw) and 11 lumen volume (Vi) measurements were made. Aiwas measured from the cut surface of 11 airways by morphometry. Airways in scanned images were matched using branching points. After calibration, the errors of Ai, Aawand ViHRCT measurements were determined.

The current authors found a systematic, size-dependent underestimation of Aiand overestimation of Aawfrom HRCT measurements. This was used to calibrate an HRCT measurement algorithm. The 95% limits of agreement of subsequent measurements were ±3.2 mm2for Ai, ±4.3 mm2for Aaw, and ±11.2 mm3for Viwith no systematic error. Morphometric measurements agreed with micro-CT (±2.5 mm2) without systematic error.

In conclusion, micro-computed tomography image data from inflation-fixed airways can be used as calibration standards for three-dimensional lumen volume measurements from high-resolution computed tomography, while morphometry is acceptable for two-dimensional measurements. The image dataset could be used to validate other developmental three-dimensional segmentation algorithms.
Effect of primary-care spirometry on the diagnosis and management of COPD
Authors: Walker P. P. , Mitchell P. , Diamantea F. , Warburton C. J. , Davies L.
Published: July 2006

Primary-care spirometry has been promoted as a method of facilitating accurate diagnosis of chronic obstructive pulmonary disease (COPD). The present study examined whether improving rates of diagnosis lead to improvements in pharmacological and nonpharmacological management.

From 1999 to 2003, the current authors provided an open-access spirometry and reversibility service to a local primary-care area, to which 1,508 subjects were referred. A total of 797 (53%) had pre-bronchodilator airflow obstruction (AFO). Of the subjects who underwent reversibility testing, 19.3% were no longer obstructed post-bronchodilator. The results and records of a subgroup of 235 subjects with post-bronchodilator AFO were examined.

Of the 235 subjects, 130 received a new diagnosis, most commonly COPD. The patients with COPD were significantly undertreated before spirometry and testing led to a significant increase in the use of anticholinergics (37versus18%), long-acting β-agonists (25versus8%) and inhaled steroids (71versus52%). More than three quarters of smokers received smoking cessation advice but very few were referred for pulmonary rehabilitation.

In conclusion, primary-care spirometry not only increases rates of chronic obstructive pulmonary disease diagnosis, but it also leads to improvements in chronic obstructive pulmonary disease treatment. The use of bronchodilator reversibility testing in this setting may be important to avoid misdiagnosis.
Evidence that mesothelial cells regulate the acute inflammatory response in talc pleurodesis
Authors: Marchi E. , Vargas F. S. , Acencio M. M. , Antonangelo L. , Genofre E. H. , Teixeira L. R.
Published: July 2006

Intrapleural instillation of talc is used to produce pleurodesis in cases of recurrent malignant pleural effusions. The mechanisms by which pleurodesis is produced remain unknown but may involve either injury or activation of the mesothelium. The aim of the current study was to assess the inflammatory response of pleural mesothelial cells to talc in an experimental model in rabbits.

A group of 10 rabbits were injected intrapleurally with talc (200 mg·kg-1) and undiluted pleural fluid was collected after 6, 24 or 48 h for measurement of interleukin (IL)-8, vascular endothelial growth factor (VEGF) and transforming growth factor (TGF)-β1. Samples of pleura were studied to assess the inflammatory infiltrate and mesothelial cell viability.

The pleural fluid IL-8 concentration peaked at 6 h, whereas VEGF and TGF-β1 concentrations increased steadily over 48 h. Immunohistochemistry for cytokeratin showed a preserved layer of mesothelial cells despite the intense inflammatory pleural reaction.

In conclusion, it is proposed that the mesothelial cell, although injured by the talc, may actively mediate the primary inflammatory pleural response in talc-induced pleurodesis.
Inspiratory fraction and exercise impairment in COPD patients GOLD stages II–III
Authors: Albuquerque A. L. P. , Nery L. E. , Villaça D. S. , Machado T. Y. S. , Oliveira C. C. , Paes Â. T. , Neder J. A.
Published: July 2006

The inspiratory-to-total lung capacity ratio or “inspiratory fraction” (inspiratory capacity(IC)/total lung capacity (TLC)) may be functionally more representative than traditional indices of resting airflow limitation and lung hyperinflation in patients with chronic obstructive pulmonary disease (COPD).

In the present retrospective study, a comparison was made of the individual performance of post-bronchodilator IC, IC/TLC and forced expiratory volume in one second (FEV1) in predicting a severely reduced peak oxygen uptake (V′O2; <60% predicted) in 44 COPD patients Global Initiative for Chronic Obstructive Lung Disease stages II-III (post-bronchodilator FEV1ranging from 31–79% pred).

Patients with lower IC/TLC values (≤0.28) showed increased lung volumes and reduced exercise capacity as compared with other subjects. Following a multiple linear regression analysis, only IC/TLC and FEV1remained as independent predictors ofV′O2(r2 = 0.33). A receiver operating characteristic (ROC) curve analysis revealed that an IC/TLC ≤0.28 had the highest specificity (89.6%), positive predictive value (80%) and overall accuracy (86.3%) in identifying patients withV′O2<60% pred. In addition, the area under the ROC curve tended to be higher for IC/TLC than IC.

In conclusion, post-bronchodilator total lung capacity-corrected inspiratory fraction provides useful information in addition to forced expiratory volume in one second and inspiratory capacity, to estimate the likelihood of chronic obstructive pulmonary disease patients to present with severely reduced maximal exercise capacity.