bluuebunny/crossref_metadata_2025 huggingface dataset:
Measurement properties of the UK-English version of the Pediatric Quality of Life Inventory™ 4.0 (PedsQL™) generic core scales
Authors: Upton Penney , Eiser Christine , Cheung Ivy , Hutchings Hayley A , Jenney Meriel , Maddocks Alison , Russell Ian T , Williams John G
Published: April 2005

Background

Health related quality of life (HRQL) has been recognised as an important paediatric outcome measurement. One of the more promising measures to emerge in recent years is the Pediatric Quality Of Life Inventory (PedsQL™), developed in the US. Advantages of the PedsQL™ include brevity, availability of age appropriate versions and parallel forms for child and parent. This study developed a UK-English version of PedsQL™ generic module and assessed its performance in a group of UK children and their parents.

Methods

PedsQL™ was translated to UK-English. The psychometric properties of the UK version were then tested following administration to 1399 children and 970 of their parents. The sample included healthy children, children diagnosed with asthma, diabetes or inflammatory bowel disease and children in remission from cancer.

Results

Psychometric properties were similar to those reported for the original PedsQL™. Internal reliability exceeded 0.70 for all proxy and self-report sub-scales. Discriminant validity was established for proxy and self-report with higher HRQL being reported for healthy children than those with health problems. Sex differences were noted on the emotional functioning subscale, with females reporting lower HRQL than males. Proxy and self-report correlation was higher for children with health problems than for healthy children.

Conclusion

The UK-English version of PedsQL™ performed as well as the original PedsQL™ and is recommended for assessment of paediatric HRQL in the UK.
Contested ground: how should qualitative evidence inform the conduct of a community intervention trial?
Authors: Riley Therese , Hawe Penelope , Shiell Alan
Published: April 2005

This paper presents issues which arose in the conduct of qualitative evaluation research within a cluster-randomized, community-level, preventive intervention trial. The research involved the collection of narratives of practice regarding the intervention by community development officers working in eight communities over a two-year period. The community development officers were largely responsible for implementing the intervention. We discuss the challenges associated with the collection of data as the intervention unfolded, in particular, the disputes over cues to revise and adjust the intervention (i.e. to use the early data formatively). We explore the ethical uncertainties that arise when multiple parties have different views on the legitimacy of types of knowledge and the appropriate role of research and theory in various trial stages. These issues are discussed drawing on the fields of ethnography, community psychology, epidemiology, qualitative methodology and notions of research reflexivity. We conclude by arguing that, in addition to the usual practice of having an outcome data-monitoring committee, community intervention trials also require a process data-monitoring committee as a forum for debate and decision-making. Without such a forum, the relevance, ethics and position of qualitative evaluation research within randomized controlled trials are destined to be a point of contention rather than a source of insight.
US physicians' perceptions of the effect of practice guidelines and ability to provide high-quality care
Authors: Bartell Jessica , Smith Maureen
Published: April 2005

Objectives: In the USA, health care organizations frequently disseminate practice guidelines to physicians, but physicians often resist implementing guidelines when they perceive no improvements in quality of care will result. Greater involvement with a single health care organization may affect physicians' perceptions of guidelines. We examined the relationship between the perceived effect of guidelines on practice and perceived quality of care for US primary care physicians (PCPs) and specialists with varying levels of financial involvement with a single managed care organization.

Methods: Data were from the 1996-1997 Community Tracking Study, a nationally representative, cross-sectional survey of 12,528 physicians. Data were adjusted for possible confounders using ordinal logistic regression.

Results: Almost half the physicians described a moderate to very large perceived effect of guidelines (46% of PCPs, 46% of specialists). Physicians' financial involvement with a single organization was modest: PCPs received on average 24% of their revenue from their largest contract, while specialists averaged 18%. For specialists, increasing perceived effect of guidelines was associated with increasingly negative perceptions of quality of care [β= –0.16, 95% confidence interval (–0.22, –0.10)]. Similar results were obtained for PCPs with low levels of financial involvement with a single organization. However, this negative association disappeared for PCPs with higher levels of financial involvement.

Conclusions: PCPs with substantial financial involvement with a single organization who perceive greater effects of guidelines on practice have less negative perceptions of their ability to provide high-quality care. Although our data cannot confirm a causal relationship, financial involvement with a single organization may be one factor linking practice guidelines to high-quality care.
Evidence-based policy making in health care: what it is and what it isn't
Authors: Cookson Richard
Published: April 2005

In this paper, I aim to re-establish the meaning and importance of the concept of 'evidence-based policy making' (EBP) in health care. The term EBP is often misunderstood as being either vacuous (who thinks that public policy should not be based on evidence?), unrealistic (the naive product of ivory tower thinking) or conservative (an excuse permanently to delay reform). It need be none of these things. EBP should be thought of as a set of rules and institutional arrangements designed to encourage transparent and balanced use of evidence in public policy making. As well as controlled trials and observational studies, a broad range of theoretical and empirical evidence about human behaviour may be relevant to predicting policy outcomes - including stakeholder opinions and other sources of intelligence that might not qualify as scientific research. Gradual progress towards EBP, properly understood, has the potential to facilitate open democracy and to improve policy outcomes. The argument is illustrated using examples based on large-scale policies of health care reform in England, where progress towards EBP over the last decade has been real but modest.
Determinants of patient and surgeon perspectives on maximum acceptable waiting times for hip and knee arthroplasty
Authors: Conner-Spady Barbara , Estey Angela , Arnett Gordon , Ness Kathleen , McGurran John , Bear Robert , Noseworthy Tom ,   The Steering Committee of the Western Canada Waiting List Project
Published: April 2005

Objectives: Lengthy waiting times for hip and knee arthroplasty have raised concerns about equitable and timely access to care. The Western Canada Waiting List project has developed priority criteria scores linked to maximum acceptable waiting times (MAWT) for different levels of priority. Our study purpose was to assess the determinants of patient- and surgeon-rated MAWT, and to test whether the anticipated waiting time has an independent influence after adjusting for age, sex and patient urgency. A second aim was to compare MAWT, waiting time and anticipated waiting time for different levels of urgency assessed using the priority criteria score.

Methods: Orthopaedic surgeons assessed 233 consecutive patients waiting for arthroplasty in terms of their urgency (assessed using the priority criteria score and a visual analogue scale), MAWT and anticipated waiting time. Patient data included urgency (assessed by a visual analogue scale), MAWT and the Western Ontario McMaster Osteoarthritis index. We used hierarchical linear regression to test the models.

Results: After adjusting for age and sex, urgency (assessed by priority criteria score and visual analogue scale) and anticipated waiting time accounted for 40% of the variance in surgeon MAWT. The patient model accounted for 30% of the variance in patient MAWT. Older patients preferred signficantly shorter MAWTs ( P <0.05). Anticipated waiting time added significantly to both the surgeon and patient MAWT models ( R2 change 0.11 and 0.07, respectively). Actual waiting time was weakly correlated with urgency assessed using the priority criteria score ( r = –0.25, P <0.0001).

Conclusions: Patients' and surgeons' views are critical to a fair process of establishing MAWT for elective procedures. Anticipated waiting time may influence the perspectives on MAWT and must be considered in their interpretation.
Glutathione S-Transferase P1 *C Allelic Variant Increases Susceptibility for Late-Onset Alzheimer Disease: Association Study and Relationship with Apolipoprotein E ε4 Allele
Authors: Bernardini Sergio , Bellincampi Lorenza , Ballerini Sabrina , Federici Giorgio , Iori Roberta , Trequattrini Alberto , Ciappi Fabrizio , Baldinetti Francesca , Bossù Paola , Caltagirone Carlo , Spalletta Gianfranco
Published: April 2005

Background: Oxidative stress and neuronal cell death have been implicated in the pathogenesis of Alzheimer disease (AD). Considering that the glutathione transferase (GST) supergene family encodes isoenzymes that appear to be critical in protection against oxidative stress, we aimed at determining the various GSTP1, GSTM1, and GSTT1 polymorphisms and ApoE genotypes to investigate their role as susceptibility genes for late-onset AD (LOAD).

Methods: We included 210 LOAD patients and 228 healthy controls matched for age, sex, and educational level in our case–control genetic association study. GSTM1 and GSTT1 genotypes were studied by conventional PCR, whereas GSTP1 and ApoE genotypes were determined by real-time PCR on the LightCycler.

Results: We found a significant association between LOAD and the GSTP1*C allelic variant [odds ratio (OR) = 1.9; P <0.05], but no association between the GSTM1 and GSTT1 deleted genotypes and LOAD. In addition, a preliminary result suggested that carriers of both the GSTP1*C and ApoE ε4 allelic variants were at increased risk of LOAD (OR = 19.98; P <0.0001).

Conclusion: The GSTP1*C allelic variant should be considered a candidate for LOAD, particularly in persons having the ApoE ε4 allelic variant, because the GSTP1 and ApoE gene products are implicated in oxidative stress and apoptosis processes leading to β-amyloid-mediated neurodegeneration.
Medium optimization for hen egg white lysozyme production by recombinant Aspergillus niger using statistical methods
Authors: Gheshlaghi R. , Scharer J.M. , Moo‐Young M. , Douglas P.L.
Published: April 2005

Statistics‐based experimental design was used to investigate the effect of medium components (starch, peptone, ammonium sulfate, yeast extract, and CaCl2 · 2H2O) on hen's egg white lysozyme production by Aspergillus niger HEWL WT‐13‐16. A 25−1 fractional factorial design augmented with center points revealed that peptone, starch, and ammonium sulfate were the most significant factors, whereas the other factors were not important within the levels tested. The method of steepest ascent was used to approach the proximity of optimum. This task was followed by a central composite design to develop a response surface for medium optimization. The optimum medium composition for lysozyme production was found to be: starch 34 g L−1, peptone 34 g L−1, ammonium sulfate 11.9 g L−1, yeast extract 0.5 g L−1, and CaCl2 · 2H2O 0.5 g L−1. This medium was projected to produce, theoretically, 212 mg L−1 lysozyme. Using this medium, an experimental maximum lysozyme concentration of 209 ± 18 mg L−1 verified the applied methodology. © 2005 Wiley Periodicals, Inc.
The role of anion channels and Ca2+ in addition to K+ channels in the physiological volume regulation of murine spermatozoa
Authors: Yeung Ching‐Hei , Barfield Jennifer P. , Cooper Trevor G.
Published: April 2005

Studies in the human, transgenic mice, and cattle indicate that sperm cell volume regulation plays an important role in male fertility as spermatozoa encounter a hypo‐osmotic challenge upon ejaculation into the female tract. Physiological regulatory volume decrease (RVD) was examined using flow cytometry in murine sperm released into incubation medium mimicking uterine osmolality and including putative channel inhibitors. The involvement of K+ channels was indicated by the recovery of volume regulation by the K+ ionophore valinomycin in defective sperm from infertile transgenic mice, and from blockage of RVD by quinine in normal sperm. However, in neither case was the recovery complete. The involvement of volume‐sensitive osmolyte and anion channels (VSOAC) were investigated using blockers effective in other cell types. NPPB (5‐nitro‐2(3‐phenylpropylamino) benzoic acid) and tamoxifen inhibited RVD but SITS (4‐acetamido‐4′‐isothiocyanato‐stilbene‐2,2′‐disulphonic acid) at 0.4 and 1 mM had no effect whereas DIDS (di‐isothiocyanato‐stilbene‐2,2′‐disulphonic acid) at 1 mM enhanced RVD. Verapamil, but not another P‐glycoprotein antagonist cyclosporin, caused sperm swelling which persisted in the presence of valinomycin, in Ca2+‐free medium and in the presence of thapsigargin, but swelling was abolished by the Ca2+ ionophore A23187. Nifedipine was slightly effective in blocking RVD. Analysis by Western blotting failed to reveal ClC‐2 and ClC‐3 members of the chloride channel family in murine or rat sperm proteins despite signal bands in positive tissue controls. These findings implicate the involvement of some unidentified VSOAC in sperm volume regulation, which is probably Ca+‐dependent. Mol. Reprod. Dev. © 2005 Wiley‐Liss, Inc.
Developing Clinical Knowledge through a Narrative-Based Method of Interpretation
Authors: Ekman Inger , Skott Carola
Published: April 2005

The results of research using a narrative analysis provide new clinical knowledge, but the methods used are unknown to many readers. In this paper we present an example of how an analysis may be performed in practice. The purpose of the interpretation of this specific story was to develop clinical knowledge of how it is to live with chronic heart failure from a daily life perspective. The steps in the interpretation process, within the framework of Paul Ricoeur's Interpretation theory, were: (1) general or naïve reading, (2) distancing, (3) examination of discourse, (4) conjectures and questions, and (5) reflection over the whole. The demonstrated interpretation of the interview resulted in a theme called: “Struggling to comprehend medical information”. This systematic way of working with narratives makes implicit assumptions about the relationship between meaning and language explicit. These themes can be used in everyday practice as clinical tools. Because of the interpretative nature of human understanding the experienced health professional will be capable of integrating evidence-based research findings and individual illness experience.
Mediolateral Graft Tympanoplasty for Anterior or Subtotal Tympanic Membrane Perforation
Authors: Jung Timothy T. K. , Park Seong Kook
Published: April 2005

OBJECTIVE:

To describe and evaluate the mediolateral graft tympanoplasty for the reconstruction of anterior or subtotal tympanic membrane (TM) perforation.

STUDY DESIGN AND SETTING:

Retrospective study of 100 patients who underwent the mediolateral graft tympanoplasty at community and tertiary care centers from 1995 to 2001. All patients underwent preoperative and postoperative audiograms. Posterior tympanomeatal flap is elevated same as in the medial (underlay) graft tympanoplasty. Anterior‐medial canal skin is elevated down to the annulus. At the annulus, only squamous epithelial layer of TM is elevated up to anterior half of the TM perforation. Temporalis fascia is grafted medial (underlay) to the posterior half of the perforation and lateral (overlay) to the anterior half of the de‐epithelialized TM perforation, up to the annulus. Anterior canal skin is rotated to cover the fascia graft and TM perforation as a second‐layer closure. Patients were followed for at least 6 months. Outcome was considered successful if the TM is intact.

RESULTS:

There were 3 failures (97% success rate), attributable to a postoperative infection, anterior blunting, and recurrent cholesteatoma, respectively. There was no significant postoperative hearing loss compared with preoperative hearing. More than 70% of the operated ears had hearing improvement of 0‐40 dB (0‐10 dB in 19% of ears, 11‐20 dB in 44%, 21‐30 dB in 7%, and 31‐40 dB in 4%) even without ossiculoplasty. With ossiculoplasty using either partial ossicular replacement prosthesis (PORP, 15%) or total ossicular replacement prosthesis (TORP, 11%), there were various degree of hearing improvement from 11 to 30 dB.

CONCLUSION AND SIGNIFICANCE:

The mediolateral graft method is superior to the traditional medial or lateral graft technique for the reconstruction of large anterior or subtotal TM perforation. This new method should help otologic surgeons to improve outcome of tympanoplasty for anterior or total TM perforation. EBM rating: C‐1.
Multilevel Temperature‐Controlled Radiofrequency for Obstructive Sleep Apnea: Extended Follow‐up
Authors: Steward David L. , Weaver Edward M. , Woodson B. Tucker
Published: April 2005

OBJECTIVE:

To determine long‐term effectiveness of multilevel (tongue and palate) temperature‐controlled radiofrequency tissue ablation (TCRFTA) for patients with obstructive sleep apnea syndrome (OSAS).

STUDY DESIGN AND SETTING:

Prospective, 2‐institution case series. Twenty‐nine subjects with mild to moderate OSAS and who were at least 1 year from completion of multilevel TCRFTA were included, representing a subset of subjects who were enrolled in a previously published controlled trial. Exclusion criteria for this extended follow‐up study included any additional treatment for OSAS after completion of TCRFTA.

RESULTS:

Median follow‐up was 23 months. Daytime sleepiness and OSAS‐related quality of life were significantly improved at extended follow‐up (both P 0.001). Median reaction time testing and apnea‐hypopnea index (AHI) were also significantly improved at long‐term follow‐up (P = 0.03 and 0.01). Body mass index was unchanged (P = 0.94).

CONCLUSIONS:

Multilevel TCRFTA treatment of mild to moderate OSAS resulted in prolonged improvement in daytime somnolence, OSAS‐related quality of life, psychomotor vigilance, and AHI in this group of subjects at extended follow‐up.
Gastric Reflux is Uncommon in Acute Post‐Tympanostomy Otorrhea
Authors: Antonelli Patrick J. , Lloyd Kristen M. , Lee James C.
Published: April 2005

OBJECTIVE:

Acute post‐tympanostomy otorrhea (APTO) is a common complication of tympanostomy tube placement. APTO has been related primarily to viral upper respiratory infections and external ear contamination. Elevated levels of gastric enzymes have been found in a large proportion of chronic middle ear effusions, implicating gastric reflux (GR) in its pathogenesis. Thus, our objective was to determine whether GR may be a contributing factor in the development of APTO.

STUDY DESIGN AND SETTING:

Prospective, nonrandomized design. Otorrhea samples were collected from children with APTO. Total pepsinogen concentrations were measured with a commercial ELISA, using a pepsinogen I–specific capture antibody and horseradish peroxidase detection antibody.

RESULTS:

Twenty‐six samples from 24 patients were collected and analyzed. Eight samples demonstrated measurable pepsinogen I, but the measured concentrations, 2‐17 mg/L, were below the normal serum reference ranges.

CONCLUSIONS:

GR does not play a major role in the development of APTO in children.
Use of Mometasone Furoate Aqueous Nasal Spray in the Treatment of Rhinitis Medicamentosa: An Experimental Study
Authors: Tas Abdullah , Yagiz Recep , Yalcin Omer , Uzun Cem , Huseyinova Gulara , Adali Mustafa K. , Karasalihoglu Ahmet R.
Published: April 2005

OBJECTIVE:

We aimed to investigate, histopathologic changes in the nasal mucosa of guinea pig's after prolonged administration of oxymetazoline and the development of rhinitis medicamentosa, and the efficacy of mometasone furoate aqueous nasal spray and saline in reversing the ultrastructural changes attributable to rhinitis medicamentosa.

METHODS:

In the study, 24 male guinea pigs (500 to 600 gr) were used. Oxymetazolin (0.05%) was sprayed into the nasal cavities of the guinea pigs 3 times daily for 8 weeks. At the end of this period, 6 guinea pigs were killed and examined to make sure that the animals had developed rhinitis medicamentosa. The remaining guinea pigs were randomly divided into 3 groups. In the first group, one spray‐puff of 0.05% mometasone furoate aqueous nasal spray (50 μg) was applied twice daily for 14 days. In the second group, saline solution (0.9% NaCl) was applied twice daily for 14 days. No treatment was performed in the third group. At the end of the treatment period, nasal mucosal changes were evaluated by light microscopy and electron microscopy.

RESULTS:

After oxymetazolin application for 8 weeks, the main histologic changes were edema, congestion, proliferation of subepithelial glands, and squamous cell metaplasia. After topical mometasone furoate aqueous spray application for 2 weeks, the edema fluid was found to diminish markedly. In the saline and no treatment groups, edema and congestion continued. In these groups of guinea pigs, fibrosis has been seen in the nasal mucosa.

CONCLUSION:

We found that mometasone furoate nasal spray was effective against experimentally induced rhinitis medicamentosa in guinea pigs. Mometasone furoate nasal spray may have value in the treatment of patients with rhinitis medicamentosa.
Primary Parapharyngeal Space Tumors in a Mexican Cancer Center
Authors: Luna‐Ortiz Kuauhyama , Navarrete‐Alemán Jaime Esteban , Granados‐García Martín , Herrera‐Gómez Angel
Published: April 2005

OBJECTIVE:

To describe clinical and demographic characteristics of the parapharyngeal space tumors and assess surgical approaches used to treat them at our institution.

METHODS:

A retrospective and descriptive study of the parapharyngeal space tumors, excluding paragangliomas, treated from June 1991 to October 2002 in a cancer center. The study population included 21 patients, 8 men and 13 women, average age of 41 years (range, 20 to 70 years). Fine needle biopsy was done in 5 (24%) patients. Computed tomography (CT) was performed in all patients, and only a few required magnetic resonance image (MRI).

RESULTS:

Surgical approaches included transcervical alone or in combination with parotidectomy, transoral, or transmandibular (mandibular swing) approach. Laminectomy and segmentary approaches were also performed in 1 patient each. Sixteen (76%) patients had benign lesions and 5 (24%) had malignant tumors. Neurogenic tumors represented 57% of all tumors. Mean tumor size was of 6.7 cm (range, 3 to 11 cm). Six (29%) patients received adjuvant radiotherapy. Complications occurred in 6 (29%) patients, 4 (19%) of which were nervous injuries associated with peripheral nerve sheath tumors. Median disease‐free follow‐up survival was 33 months (range, 2 to 184 months) despite being an heterogeneous group of histologies.

CONCLUSION:

Parapharyngeal space is a rare location for head and neck tumors. Cervical approach should be the first choice for large tumors; transoral approach is reserved for tumors less than 3 cm. Conversion to mandibular swing approach when the cervical approach is not offering proper exposure for tumor resection is indicated. Preoperative histologic diagnosis is not required. Nevertheless, CT scan should always be performed in order to exclude paragangliomas, distinguish prestyloid from poststyloid lesions, and to assess the extension of the tumor as well as its relationship with adjacent structures.
Ultrastructural Detection of Nitric Oxide in Human Nasal Mucosa
Authors: Knipping Stephan , Holzhausen Hans Jürgen , Berghaus Alexander , Bloching Marc , Riederer Andreas
Published: April 2005

OBJECTIVE:

Nasal vasculature and seromucous glands are exposed to complex mechanisms influenced by external as well as internal stimuli. In addition to classic and peptidergic neurotransmitters, nitric oxide (NO) was increasingly found to be important in the control of various physiologic functions. NO modulates nasal immunology, influences macrophage activity, and has antiviral and bacteriostatic properties. The aim of this study was to show the localization of nitric oxide synthases (NOS) I and III in the normal human nasal mucosa by using immunoelectron microscopical techniques.

STUDY DESIGN:

Specimens of noninflammed inferior turbinates from 35 patients who underwent nasal surgery were fixed in phosphate‐buffered glutaraldehyde. After dehydration, incubation in unicryl and polymerization, ultrathin sections were cut. Primary antibodies against NOS I and III were applied and the immunocomplexes were visualized by an immunocytochemical staining‐technique using gold‐labeled antibodies. Immunostained structures were photodocumented using a transmission electron microscope.

RESULTS:

NOS‐immunoreactive nerve fibers were mainly co‐located in parasympathetic nerves in the adventitia of arterial vessels and in periglandular axons. Electron microscopy showed that NOS‐positive axons were in close contact with acinus cells. A strong NOS III‐immunoreactivity was found in endothelial cells of capillaries near the glands as well as in arterial vessels. Furthermore, immunoreaction products were deposited throughout the cytoplasm of fibroblasts.

CONCLUSION:

Nitric oxide in nerve fibers, seromucous glands, and endothelial cells of capillaries and arterial vessels suggest that NO takes part in the regulation of physiologic processes of the human nasal mucosa. NOS was co‐localized in para‐sympathetic nerves and plays a role in the neurotransmission and neuromodulation of the vascular tone and glandular secretion. Arteries showed a distinctly developed nitrergic innervation and endothelial accumulation. The NO production in axons of the adventitia and in the endothelium of arteries demonstrated that these vessels are influenced by a dual NO system. NO could mainly act on these structures with vasodilatatory effects. Finally, NO would be able to influence the functions of perivascular fibroblasts.
Eustachian Tube Dysfunction in Allergic Rhinitis
Authors: Lazo‐Sáenz Juan Gerardo , Galván‐Aguilera Armando Alejando , Martínez‐Ordaz Verónica Araceli , Velasco‐Rodríguez Víctor Manuel , Nieves‐Rentería Armando , Rincón‐CastañEda Cuauhtémoc
Published: April 2005

OBJECTIVE:

To assess eustachian tube function in patients with allergic rhinitis and compare them with a control group.

STUDY DESIGN AND SETTING:

Tympanometry was performed in 130 patients (260 ears), divided into 2 groups: 80 cases with allergic rhinitis and 50 healthy controls. Cases underwent skin hypersensitivity tests.

RESULTS:

Cases, age 21.1 ± 14.9; Controls, age 23.9 ± 15.6. Most frequent skin hypersensitivity: Dermatophagoides pt (62%), Zea Maiz (44%), and Cockroach (37%). Tympanometry of cases showed negative values of peak tympanometric pressure in both children and adults (P ≤ 0.05). Among children under 11 years of age, 15.5% tympanograms showed abnormal curves (13% C curves and 3% B curves); among the control group only normal curves were found (type A).

CONCLUSION:

Allergic rhinitis patients have a higher risk of eustachian tube dysfunction, particularly during childhood. Tympanometry is a noninvasive, readily available procedure that may be useful in these patients to prevent chronic middle‐ear disease.
Nighttime cirrus detection using Atmospheric Infrared Sounder window channels and total column water vapor
Authors: Kahn Brian H. , Liou Kuo Nan , Lee Sung‐Yung , Fishbein Evan F. , DeSouza‐Machado Sergio , Eldering Annmarie , Fetzer Eric J. , Hannon Scott E. , Strow L. Larrabee
Published: April 2005

A method of cirrus detection at nighttime is presented that utilizes 3.8 and 10.4 μm infrared (IR) window brightness temperature differences (dBT) and total column precipitable water (PW) measurements. This technique is applied to the Atmospheric Infrared Sounder (AIRS) and Advanced Microwave Sounding Unit A (AMSU‐A) instrument suite on board EOS‐Aqua, where dBT is determined from sets of carefully selected AIRS window channels, while PW is derived from the synergistic AIRS and AMSU‐A water vapor retrievals. Simulated and observed dBT for a particular value of PW are not constant; several physical factors impact dBT, including the variability in temperature and relative humidity profiles, surface emissivity, instrument noise, and skin/near‐surface air temperature differences. We simulate clear‐sky dBT over a realistic range of PWs using 8350 radiosondes that have varying temperature and relative humidity profiles. Thresholds between cloudy and uncertain sky conditions are derived once the scatter in the clear‐sky dBT is determined. Simulations of optically thin cirrus indicate that this technique is most sensitive to cirrus optical depth in the 10 μm window of 0.1–0.15 or greater over the tropical and subtropical oceans, where surface emissivity and skin/near‐surface air temperature impacts on the IR radiances are minimal. The method at present is generally valid over oceanic regions only, specifically, the tropics and subtropics. The detection of thin cirrus, and other cloud types, is validated using observations at the Atmospheric Radiation Measurement (ARM) program site located at Manus Island in the tropical western Pacific for 89 coincident EOS‐Aqua overpasses. Even though the emphasis of this work is on the detection of thin cirrus at nighttime, this technique is sensitive to a broad cloud morphology. The cloud detection technique agrees with ARM‐detected clouds 82–84% of the time, which include thin cirrus, as well as other cloud types. Most of the disagreements are well explained by AIRS footprint‐scale heterogeneity compared to ARM point measurements, cirrus overlying lower‐layer water clouds, possible mixed phase microphysics in midlevel clouds, and significant IR channel noise for cold BT scenes over deep convective towers.
On the asymptotics of some large Hankel determinants generated by Fisher–Hartwig symbols defined on the real line
Authors: Garoni T. M.
Published: April 2005

We investigate the asymptotics of Hankel determinants of the form detj,k=0N−1[∫ΩdxωN(x)∏i=1m∣μi−x∣2qixj+k] as N→∞ with q and μ fixed, where Ω is an infinite subinterval of R and ωN(x) is a positive weight on Ω. Such objects are natural analogs of Toeplitz determinants generated by Fisher–Hartwig symbols, and arise in random matrix theory in the investigation of certain expectations involving random characteristic polynomials. The reduced density matrices of certain one-dimensional systems of trapped impenetrable bosons can also be expressed in terms of Hankel determinants of this form. We focus on the specific cases of scaled Hermite and Laguerre weights. We compute the asymptotics by using a duality formula expressing the N×N Hankel determinant as a 2(q1+⋯+qm)-fold integral, which is valid when each qi is natural. We thus verify, for such q, a recent conjecture of Forrester and Frankel derived using a log-gas argument.
Variable transformer for controllable flux coupling
Authors: Castellano M. G. , Chiarello F. , Leoni R. , Simeone D. , Torrioli G. , Cosmelli C. , Carelli P.
Published: April 2005

We discuss and demonstrate a prototype of superconducting transformer with a flux transfer function that can be varied in a wide range, by acting on a control parameter. The device is realized by inserting a small hysteretic superconducting quantum interference device (dc-SQUID) with unshunted junctions, working as a Josephson junction with flux-controlled critical current, parallel to a superconducting transformer; by varying the magnetic flux coupled to the dc-SQUID, the transfer function for the flux coupled to the transformer can be varied. This feature can prove particularly appealing in the field of quantum computing, where it could be exploited to achieve a controllable magnetic coupling among flux-based qubits. Measurements carried out on a prototype at 4.2K show a reduction factor of about 30 between the “on” and the “off” states. We discuss the system characteristics and the experimental results.
Noncontact density measurements of liquid, undercooled, and high temperature solid boron
Authors: Paradis Paul-François , Ishikawa Takehiko , Yoda Shinichi
Published: April 2005

Electrostatic levitation in vacuum prevented contamination and multibeam heating overcame sample position stability problems occurring when handling boron at high temperatures. This allowed the density determination of the liquid as well as the high temperature solid states. Over the 2275–2460 K interval, the density of the liquid and undercooled phases was measured as ρL(T)=2.17×103–0.25(T–Tm)kgm−3, where Tm is the melting temperature (2360 K). Similarly, the density of the solid phase was measured as ρS(T)=2.11×103−0.09(T–Tm)kgm−3 over the 2010–2360 K range. These data provided clear experimental evidence that boron contracts (nearly 3%) upon melting, thus settling a decade long debate.
Functional insights from the distribution and role of homopeptide repeat-containing proteins
Authors: Faux Noel G. , Bottomley Stephen P. , Lesk Arthur M. , Irving James A. , Morrison John R. , de la Banda Maria Garcia , Whisstock James C.
Published: April 2005

Expansion of “low complex” repeats of amino acids such as glutamine (Poly-Q) is associated with protein misfolding and the development of degenerative diseases such as Huntington's disease. The mechanism by which such regions promote misfolding remains controversial, the function of many repeat-containing proteins (RCPs) remains obscure, and the role (if any) of repeat regions remains to be determined. Here, a Web-accessible database of RCPs is presented. The distribution and evolution of RCPs that contain homopeptide repeats tracts are considered, and the existence of functional patterns investigated. Generally, it is found that while polyamino acid repeats are extremely rare in prokaryotes, several eukaryote putative homologs of prokaryote RCP—involved in important housekeeping processes—retain the repetitive region, suggesting an ancient origin for certain repeats. Within eukarya, the most common uninterrupted amino acid repeats are glutamine, asparagines, and alanine. Interestingly, while poly-Q repeats are found in vertebrates and nonvertebrates, poly-N repeats are only common in more primitive nonvertebrate organisms, such as insects and nematodes. We have assigned function to eukaryote RCPs using Online Mendelian Inheritance in Man (OMIM), the Human Reference Protein Database (HRPD), FlyBase, and Wormpep. Prokaryote RCPs were annotated using BLASTp searches and Gene Ontology. These data reveal that the majority of RCPs are involved in processes that require the assembly of large, multiprotein complexes, such as transcription and signaling.
Action‐at‐a‐distance interactions enhance protein binding affinity
Authors: Joughin Brian A. , Green David F. , Tidor Bruce
Published: April 2005

The identification of protein mutations that enhance binding affinity may be achieved by computational or experimental means, or by a combination of the two. Sources of affinity enhancement may include improvements to the net balance of binding interactions of residues forming intermolecular contacts at the binding interface, such as packing and hydrogen‐bonding interactions. Here we identify noncontacting residues that make substantial contributions to binding affinity and that also provide opportunities for mutations that increase binding affinity of the TEM1 β‐lactamase (TEM1) to the β‐lactamase inhibitor protein (BLIP). A region of BLIP not on the direct TEM1‐binding surface was identified for which changes in net charge result in particularly large increases in computed binding affinity. Some mutations to the region have previously been characterized, and our results are in good correspondence with this results of that study. In addition, we propose novel mutations to BLIP that were computed to improve binding significantly without contacting TEM1 directly. This class of noncontacting electrostatic interactions could have general utility in the design and tuning of binding interactions.
A statistical power analysis of the ‘internal reference’ technique for comparing growth and growth depensation of tilapia strains
Authors: Basiao Z. U. , Doyle R. W. , Arago A. L.
Published: April 2005

Experiments were conducted to compare the growth and growth compensation of three strains of juvenile Oreochromis niloticus. Ten full sib families (10 replicates) per strain were split and grown under crowded and uncrowded conditions for 3 weeks (the treatment). Both treatments were then grown an additional 12 weeks under less crowded conditions (the compensation). Standard length measurements were made at the end of crowding and the end of compensation. Each replicate included a size‐matched control population of a fourth (red) reference strain. ANCOVA with the reference strain used as a cofactor revealed significant strain effects on specific growth throughout the experiment. The reference strain removed most of the random among‐replicate error variance as shown by an increase of r 2 from 0.06 to 0.91 when it was included in the statistical models. If the reference fish had not been used, approximately 450 replicate families would have been needed to achieve the sensitivity of the present experiment (a difference of 7% among strains significant at P=0.05). We conclude that the CLSU strain grows significantly more slowly than the Israel and NIFI strains under the experimental conditions, that the crowding effect was essentially eliminated after 12 weeks of compensation, and that the reference strain greatly improved the resolution of the strain‐testing experiment.
Measurements of aerobic metabolism of a school of horse mackerel at different swimming speeds
Authors: Wardle C. S. , Soofiani N. M. , O'Neill F. G. , Glass C. W. , Johnstone A. D. F.
Published: April 2005

Oxygen consumption rates were measured in a school of 56 horse mackerel Trachurus trachurus while at rest and while swimming at steady sustained speeds. Resting values of 38.76 and 42.10mg O2 kg−1 h−1 were measured in a sealed cylindrical tank (535 l) while observing that the fish school remained neutrally buoyant and inactive with only gentle pectoral fin movements and no swimming motion. The same school was trained to swim with projected light patterns within a 10‐m diameter annular doughnut respirometer. The oxygen consumption increased from the resting level through 51 mg O2 kg−1 h−1 at the slowest swimming speeds of 0.29 m s−1 (0.95 L s−1) to around 259 mg O2 kg−1 h−1 at the higher measured swimming speed of 0.87 m s−1 (2.82 L s−1). The data fitted a curve where oxygen consumption rose in proportion to velocity to the power of 2.56 with the intercept at the resting level. The maximum sustained speed (80 min) of 1.12 m s−1 (3.63 Ls−1) was not achieved within the respirometer but corresponded to an estimated oxygen consumption of 458.33 mg O2 kg−1 h−1 giving a scope for aerobic activity of 419.02 mg O2 kg−1 h−1. At a speed of 0.87 m s−1, there was a lower bound on the aerobic efficiency of at least 38% and at 1.12 m s−1, the highest aerobic speed, of 40%. Sustained speeds swum in a curved path as here should be increased by 5% for a straight path giving a maximum sustained 80 min speed of 1.18 m s−1.
Metabolic recovery in herring larvae following strenuous activity
Authors: Franklin C. E. , Johnston I. A. , Batty R. S. , Yin M. C.
Published: April 2005

Larvae of spring spawning Clyde herring Clupea harengus L. were reared at 5 and 12° C. Metabolism following burst swimming was studied in 7‐day‐old larvae at their respective rearing temperatures. Escape responses were repeatedly elicited using tactile stimulation for a period of 3 min. Larval herring were hard to fatigue and still responded to tactile stimuli after 3 min. Whole larvae were freeze‐quenched in liquid nitrogen, either immediately after exercise, or after periods of recovery of up to 24 h. Samples were freeze‐dried and analysed for whole body creatine (Cr), phosphocreatine (PCr), ATP, ADP, AMP, lactate, glucose, and glycogen using high performance liquid chromatography and enzymatic methods. The exercise regime resulted in a marked decrease in PCr, ATP and glycogen concentrations and an increase in creatine, glucose and lactate concentrations whereas there was no significant change in either AMP or ADP concentrations. The extent of phosphagen hydrolysis (approx. 110 to 15μmol PCr g −1 dry body mass) and lactate accumulation (approx. 7 to 40 μmol lactate g−1 dry body mass) over the exercise period was similar at the two temperatures, consistent with a relatively constant degree of effort. The rates of recovery of PCr and ATP were essentially the same at 5 and 12° C; returning to resting levels after approximately 30 min. Lactate and glycogen concentrations were restored 60 min after exercise at both temperatures. Maximum lactate clearance rates (1.2 μmol min −1 g −1 wet muscle mass) were an order of magnitude faster than reported for adult fish in the literature.
Egg‐to‐fry survival of the sea trout in some streams of Gotland
Authors: RUBIN J.‐F. , GLIMSÄTER C.
Published: April 2005

The quality of the surface water of Gotland (Sweden) streams was good, and did not limit sea trout egg‐to‐fry (ETF) survival. The oxygen concentration of the interstitial water was positively correlated to the permeability of the stream bed, and to the geometric mean diameter of the substratum. When the oxygen at 15 cm inside the stream bed was undiminished from surface values, the permeability of the stream bed was at least 6000 cm h–1 and the geometric mean diameter of the substratum at least 15.0 mm. When the interstitial oxygen concentration increased, the interstitial ammonium concentration decreased, the NO2 concentration remained stable and the NO3 concentration increased. The ETF survival up to hatching was highly dependent upon the oxygen concentration of the interstitial water. For survival from hatching to emergence, the geometric mean diameter of the substratum was the most important factor. ETF survival >50% was observed where the interstitial oxygen concentration averaged at least 10mg I‐1, the substratum permeability at least 2000cm h‐1 and the substratum geometric mean diameter at least 15 mm. Other factors, such as overdigging and drying out of the spawning grounds could increase the ETF mortality.
A new approach to graphical analysis of feeding strategy from stomach contents data—modification of the Costello (1990) method
Authors: Amundsen P.‐A. , Gabler H.‐M. , Staldvik F. J.
Published: April 2005

A modification of the graphical Costello method is proposed for the analysis of stomach contents data. The new method allows prey importance, feeding strategy and the interand intra‐individual components of niche width to be explored using graphical presentation. The analysis is based on a two‐dimensional representation of prey‐specific abundance and frequency of occurrence of the different prey types in the diet. The paper describes the new method and the parameters therein, and also present some examples of the utilization of the method. The method may be particularly well‐suited for the examination of predictions made from optimal foraging, competition and niche theories.
Seasonal variation in trypsin activity in juvenile Atlantic salmon upper and lower modal groups
Authors: Einarsson S. , Jönsson A. C. , Davies P. Spencer
Published: April 2005

Juvenile salmon in their first year of growth showed a bimodal distribution of body lengths by December. For experimental purposes samples of fish from the upper 2% of body lengths were taken as representing the upper modal group (UMG), whilst fish from the bottom 5% of body lengths were taken to represent the lower modal group (LMG). The population of fish from which the samples were taken were fed ad libitum from December to July. During the winter months to March, neither group increased in weight. Growth resumed between March and July. The LMG fish had a very low food intake, as indicated by the relative weight of digesta in the stomach, in the winter months. However, following resumption of feeding, the relative weight of stomach digesta of the LMG fish exceeded that of the UMG fish between May and July. The activity of trypsin in the intestinal digesta followed a similar pattern, the LMG fish showing a higher trypsin activity in the spring months. Starvation of UMG fish for 5 days in winter resulted in accumulation of trypsin in the pancreatic tissues, whilst injection of the trypsin releasing hormone cholecystokinin (CCK) into starving UMG fish resulted in reduction of trypsin in the secretory tissues. CCK also caused reduction of trypsin in the pancreatic tissues of LMG fish, suggesting that the pancreas of this group is potentially fully functional during the winter period. Ultrastructure studies of the pancreatic acinar cells showed evidence for lower secretory activity in the LMG fish, as indicated by smaller numbers of zymogen granules, less well developed Golgi systems and a smaller number of active secreting cells. It appears that trypsin secretion by the pancreas in LMG fish is at a low level during the winter, in response to the reduced amounts of food passing through the gut, which is ultimately controlled by changes in food intake, lowered metabolic level and lowered appetite levels.
Reproductive biology, species status and taxonomic relationships of four recently discovered galaxiid fishes in a New Zealand river
Authors: Allibone R. M. , Townsend C. R.
Published: April 2005

The reproductive biology of four recently discovered, largely allopatric non‐migratory Galaxias species in the Taieri River, New Zealand, was compared with the closely related Galaxias vulgaris. Timing of spawning was similar (late winter/spring) but spawning habitat, spawning behaviour and nest structure differed among the Taieri species and G. vulgaris. Patterns of fecundity also differed among the Taieri species but, with G. vulgaris, they form a distinct group of galaxiids with maxima of 800–1500 eggs having diameters of 2·3–2·8 μn. The different spawning behaviours of the Taieri galaxiids, in particular the differences in spawning orientation, provide evidence for prezygotic isolating mechanisms and support their status as separate species. In cladistics terms, the results indicate that Galaxias anomalus, G. eldoni and G. vulgaris are sister taxa, while G. depressiceps and Galaxias sp. form a second cluster.
Sample sizes for length and density estimation of 0+ fish when using point sampling by electrofishing
Authors: Garner P.
Published: April 2005

Standard lengths of cyprinids at several sites in the River Great Ouse, England, were compared between catches taken using a conventional 15 × 3 m micromesh seine (pore diameter 2 mm) and using point sampling by electrofishing (PSE). No statistically significant differences in sites were found in six out of 10 trials. In nine out of 10 trials, the difference between the mean lengths differed by <1 mm. No serial bias was found between PSE and seine netting for cyprinid fishes between 14 and 100 mm SL, although variation between size classes was high, owing to small sample sizes. The coefficient of variation in fish length with size tended to increase with the age of 0+Rutilus rutilus. The relationship between sample size (n) and variance (s2) was explained by s2=13·9 n−1·24. Sampling more than 30 fish resulted in little increase in precision. The relationship between the mean catch per site (x̄) and the variance of the mean estimate was log s2=1·6039 log x̄+0·973. The number of samples required to estimate density within a given variance range was: n=9·33 x̄1·6–2CVx̄−2. Given the high variance‐mean ratio, great care should be taken when interpreting density data collected using PSE, and 50 point samples is the minimum required for density estimation.