bluuebunny/crossref_metadata_2025 huggingface dataset:
Langerhans' cell histiocytosis – A rare cause of sudden onset unilateral sensorineural hearing loss
Authors: Hore I. , Mitchell R. B. , Radcliffe G. , Quiney R. , Walker T.
Published: November 2007

Langerhans' cell histiocytosis is a rare disorder of unknown aetiology in which pathological Langerhans' cells accumulate and destroy local tissue. We report a 38-year-old female who presented with a sudden onset of left sensormeural hearing loss. Magnetic resonance imaging (MRI) revealed a contrast-enhancing lesion in the left mastoid and a second lesion in the hypothalamus. Following left mastoid exploration and biopsy a definitive diagnosis of Langerhans' cell histiocytosis was made and the patient was treated with external beam radiotherapy. Subsequent right femur and right mastoid involvement were successfully treated with steroids and cytotoxic chemotherapy. At one year follow-up the patient had residual left-sided sensorineural hearing loss with normal hearing in the right ear. To our knowledge, Langerhans' cell histiocytosis has not been previously reported as a cause of unilateral sudden onset sensorineural hearing loss. It should be considered in the differential diagnosis of this condition.
An unusual complication of chemotherapy: an abscess in the pterygopalatine fossa
Authors: Lale A. M. , Jani P. J. , Ellis P. D. M.
Published: November 2007

Abscesses of the pterygopalatine fossa are extremely rare. The cases reported in the literature are all secondary to dental or periodontal disease. We present a case of an abscess in this site which was a complication of chemotherapy and was the result of haematogenous spread.
Idiopathic midline destructive disease – does it exist?
Authors: Barker T. H. W. , Hosni A. A.
Published: November 2007

There is controversy whether idiopathic mid-line destructive disease remains a valid entity, some authors considering that such cases are unrecognized malignant lymphoma or Wegener's disease. A case is presented in which numerous nasal biopsies over several years failed to show evidence of either lymphoma or Wegener's disease. Molecular genetic analysis of archival tissue did not demonstrate a monoclonal lymphoid population. It is proposed that idiopathic mid-line destructive disease remains a valid description in a small number of cases.
‘Collective Stapedectomy’ (An approach to the numbers problem)
Authors: Conrad G. J.
Published: November 2007

The results of a first series of fifty stapedectomies, using newly adopted ‘Fisch stapedotomy technique’ are presented and contrasted with ‘world results’ and results of leading otologists.

The essential points in the evolution of stapes surgery are outlined.

In the light of the small number of deaf otosclerotics the philosophy of who should be performing stapes surgery and who should be trained to perform it, is discussed.

The title ‘Collective Stapedectomy’ denotes personal system of collecting patients from the waiting list in batches and operating on each stapedectomy batch in consecutive fashion.
Aniridia and deafness: an inherited disorder
Authors: Courteney-Harris R. G. , Mills R. P.
Published: November 2007

A previously unreported association between aniridia and congenital sensorineural deafness is reported in a family in which the father and one child possess the combination of abnormalities. One of the remaining two children also has a congenital sensorineural hearing loss without any occular abnormalities.
Hypopharyngeal inverted papilloma
Authors: Hampal S. , Hawthorne M.
Published: November 2007

A case of inverted papilloma of the hypopharynx is described. Review of the literature failed to reveal any previous case reports of inverted papilloma of the hypopharynx.
Silver tracheostomy tube obturator in the tracheobroncial tree
Authors: Nicolaides A. R.
Published: November 2007

An unusual incident of aspiration of a silver tracheostomy tube obturator is described. Common sense advice to patients performing home tracheostomy care may help avoid similar occurrences in the future.
Effect of tonsillectomy on recurrent sore throats in adults: patients' perspectives
Authors: Oluwasanmi Adenike Folake , Thornton Martin Robert , Khalil Hisham Saleh , Tierney Paul Anthony
Published: November 2007

The aim of this study was to quantify the effect of tonsillectomy on the incidence of sore throats and its co-morbidity in adult patients. One hundred and nineteen adult patients were sent a standard questionnaire regarding their symptoms in the 12 months preceding and following their tonsillectomy. Outcome measures included the incidence of sore throats, total number of days with sore throat, amount of time taken off work or school, and number of visits to the general practitioner (GP). In addition, patients were asked to indicate the duration of their symptoms and whether or not they found the tonsillectomy effective in curing their sore throats.

Sixty-six patients (55.5 per cent) returned completed questionnaires. The age of the patients ranged from 16 to 39 years. The mean duration of symptoms was 8.3 years. On average, patients had 8.1 different sore throat episodes, 42 sore throat days, 21.4 days of sore throat related absence from work or school, and 5.9 visits to the GP in the 12 months before their operation. For the 12 months after surgery, these reduced to 0.9 episodes, four days, 2.2 days and 0.6 visits, respectively. This reduction was very significant (p < 0.001, Wilcoxon signed rank test).

After their surgery, more than half the patients achieved complete resolution of all the measured parameters mentioned above. Most of the remaining patients achieved at least 50 per cent resolution. Only three patients (4.8 per cent) achieved less than 50 per cent resolution. Ninety-five per cent of the patients found the operation effective in curing their sore throats and were glad they had had surgery.

In conclusion, retrospective questionnaire data must be interpreted with some caution, but this study suggests that tonsillectomy is effective in reducing the incidence, duration and co-morbidity of recurrent sore throats in adults; this must be balanced against the post-operative problems in a minority of patients.
The mental health of clean-up workers 18 years after the Chernobyl accident
Authors: Loganovsky K. , Havenaar J. M. , Tintle N. L. , Guey L. T. , Kotov R. , Bromet E. J.
Published: November 2007

Background

The psychological aftermath of the Chernobyl accident is regarded as the largest public health problem unleashed by the accident to date. Yet the mental health of the clean-up workers, who faced the greatest radiation exposure and threat to life, has not been systematically evaluated. This study describes the long-term psychological effects of Chernobyl in a sample of clean-up workers in Ukraine.

Method

The cohorts were 295 male clean-up workers sent to Chernobyl between 1986 and 1990 interviewed 18 years after the accident (71% participation rate) and 397 geographically matched controls interviewed as part of the Ukraine World Mental Health (WMS) Survey 16 years after the accident. The World Health Organization (WHO) Composite International Diagnostic Interview (CIDI) was administered. We examined group differences in common psychiatric disorders, suicide ideation and severe headaches, differential effects of disorder on days lost from work, and in the clean-up workers, the relationship of exposure severity to disorder and current trauma and somatic symptoms. Analyses were adjusted for age in 1986 and mental health prior to the accident.

Results

Relatively more clean-up workers than controls experienced depression (18.0% v. 13.1%) and suicide ideation (9.2% v. 4.1%) after the accident. In the year preceding interview, the rates of depression (14.9% v. 7.1%), post-traumatic stress disorder (PTSD) (4.1% v. 1.0%) and headaches (69.2% v. 12.4%) were elevated. Affected workers lost more work days than affected controls. Exposure level was associated with current somatic and PTSD symptom severity.

Conclusions

Long-term mental health consequences of Chernobyl were observed in clean-up workers.
The prevalence, distribution and severity of detectable pathological lesions in badgers naturally infected withMycobacterium bovis
Authors: JENKINS H. E. , MORRISON W. I. , COX D. R. , DONNELLY C. A. , JOHNSTON W. T. , BOURNE F. J. , CLIFTON-HADLEY R. S. , GETTINBY G. , McINERNEY J. P. , WATKINS G. H. , WOODROFFE R.
Published: November 2007

The Randomized Badger Culling Trial (RBCT) began in 1998 to determine the impact of badger culling in controlling bovine tuberculosis in cattle. A total of 1166 badgers (14% of total) proactively culled during the RBCT were found to be tuberculous, offering a unique opportunity to study the pathology caused byMycobacterium bovisin a large sample of badgers. Of these, 39% of adults (~6% of all adults culled) had visible lesions (detectable at necropsy) of bovine tuberculosis; cubs had a lower prevalence of infection (9%) but a higher percentage of tuberculous cubs (55·5%) had visible lesions. Only ~1% of adult badgers had extensive, severe pathology. Tuberculous badgers with recorded bite wounds (~5%) had a higher prevalence of visible lesions and a different distribution of lesions, suggesting transmission via bite wounds. However, the predominance of lesions in the respiratory tract indicates that most transmission occurs by the respiratory route.
Kinder und Jugendliche als pflegende Angehörige: Wer sie sind und was sie leisten. Eine internationale Literaturstudie (1990–2006)
Authors: Metzing Sabine , Schnepp Wilfried
Published: November 2007

Bei wachsendem Wissen zur Situation erwachsener pflegender Angehöriger ist hierzulande fast nichts über Art und Umfang der Unterstützung und Pflege durch Kinder und Jugendliche bekannt. Die vorliegende Literaturstudie ist Teil einer Untersuchung, deren Ziel es ist, diese Lücke für Deutschland zu schließen. In primär englischsprachigen Publikationen der letzten 15 Jahre wurde Fragen nach charakterisierenden Merkmalen von pflegenden Kindern und ihren Familien nachgegangen. Es liegt keine einheitliche Definition darüber vor, was ein pflegendes Kind ist. Die Prävalenz pflegender Kinder wurde lange unterschätzt; für Großbritannien beträgt sie 1.5% aller Kinder unter 18 Jahren. Kinder werden in jedem Alter pflegerisch tätig, und der Umfang ihrer Aufgaben wächst mit dem Alter. Der größere Anteil pflegender Kinder lebt in Einelternfamilien, bei den allein erziehenden Eltern handelt es sich mehrheitlich um Mütter. Bei mehr als der Hälfte der pflegebedürftigen Angehörigen liegen körperliche Gesundheitsprobleme vor. Für die Art pflegerischer Hilfen die Kinder leisten, wird ein breites Spektrum beschrieben; pflegende Kinder tun, was erwachsene Angehörige auch tun. Die Literatur lässt jedoch kein einheitliches Kategorialsystem erkennen, was einen Datenvergleich von unterschiedlichen Forschergruppen erschwert. Offensichtlich mangelt es an theoretischen Bezugsrahmen. Da davon auszugehen ist, dass Kinder und Jugendliche auch hierzulande pflegerisch tätig werden (können), gilt es, dies in Deutschland unter den spezifischen Bedingungen des deutschen Versorgungssystems zu untersuchen.
Isotopic analysis of aerosol sulfate and nitrate during ITCT‐2k2: Determination of different formation pathways as a function of particle size
Authors: Patris N. , Cliff S. S. , Quinn P. K. , Kasem M. , Thiemens M. H.
Published: November 2007

The triple isotopic composition of oxygen in sulfate and nitrate, and the sulfur isotopic composition of the sulfate fine fraction, have been measured on size‐segregated aerosol samples collected at Trinidad Head, coastal California, alongside the ITCT‐2k2 campaign in April–May 2002. The isotopic anomaly Δ17O = δ17O − 0.52 × δ18O has been determined in both sulfate and nitrate and was used as a specific tracer of the formation pathways of these species. Coarse mode sulfate in all samples exhibited a small but significant Δ17O anomaly indicating either uptake or in situ formation of secondary sulfate on sea spray. Non‐sea‐salt sulfate Δ17O in the coarse fraction is consistent with (1) either primarily coagulation of finer sulfate particles, when Δ17O is low in all size fractions, or (2) ozone‐driven oxidation of SO2 within the sea spray, as observed in the relatively higher Δ17O in coarse particles compared to fine. It is proposed that triple‐isotope measurements of sulfate oxygen can be used to quantify the budget of in situ sea spray nss‐SO4 formation. The Δ17O measured in size‐resolved nitrate revealed, for the first time, differences in the nitrate formation budget as a function of particle size in a given air mass. The coarse particle nitrate possessed a higher Δ17O, suggesting a relatively larger N2O5 hydrolysis contribution to the nitrate formation budget compared to fine particles where homogeneous formation is more important. We conclude that the complete isotope ratio analysis may provide a basis for future modeling of the formation and transformation processes of the soluble aerosol, based on direct observation of the mechanisms.
Plasmapause equatorial shape determination via the Minimum L Algorithm: Description and evaluation
Authors: Wang Cuilan , Newman Timothy S. , Gallagher Dennis L.
Published: November 2007

Algorithms for determination of the equatorial shape of the plasmapause using NASA IMAGE Extreme Ultraviolet (EUV) imagery are considered. Focus is on the Minimum L Algorithm, which operates without human intervention given a single EUV image in which the plasmasphere silhouette boundary has been identified. For each line of sight (LOS) through pixels on the plasmasphere silhouette boundary, the algorithm first finds all magnetic dipole field lines intersected by the LOS and then returns as the plasmasphere's boundary the field line with the minimum L value. An analysis of the reasonableness, applicability, and accuracy of the algorithm is presented, and it is contrasted with the well‐known Edge Algorithm (Roelof and Skinner, 2000). A revised version of the Edge Algorithm is also introduced. Application of all three algorithms to real EUV imagery is demonstrated.
HF modulated ionospheric currents
Authors: Payne J. A. , Inan U. S. , Foust F. R. , Chevalier T. W. , Bell T. F.
Published: November 2007

The HAARP HF facility is used to modulate the components of the auroral electrojet that flow in the D‐region of the ionosphere, creating ELF/VLF radiation which is then measured at a receiver co‐located with the HAARP HF antenna. An HF heating model is coupled to a full wave plasma interaction FDTD code to determine the ELF/VLF response of the ionospheric plasma to the modulated HF stimulation. The predicted FDTD fields on the ground are found to be in remarkable agreement with those measured at a receiver co‐located with HAARP. The FDTD code also predicts an upwardly propagating whistler mode that is tightly bound to the magnetic field lines.
High‐frequency asymptotic solutions benchmarking skew incidence diffraction by anisotropic impedance half and full planes
Authors: Nepa Paolo , Manara Giuliano , Armogida Andreina , Osipov Andrey
Published: November 2007

The diffraction of plane waves obliquely incident on the edge of anisotropic impedance half and full planes is investigated. Homogeneous anisotropic impedance boundary conditions are defined on both faces of the canonical structures under study, the principal anisotropy axes being parallel and perpendicular to the edge. Rigorous integral representations for the longitudinal field components are derived by applying the Sommerfeld‐Maliuzhinets method for a set of specific electrical configurations. Explicit uniform asymptotic expressions for the fields are given in the format of the Uniform Geometrical Theory of Diffraction (UTD). Although obtained for a specific class of geometrical and electrical configurations, these high‐frequency solutions provide a contribution for investigating the effects of material anisotropy on edge diffraction, as they represent a new set of reference cases for either developing perturbative solutions or testing numerical and approximate analytical methods of more general validity. Furthermore, these solutions extend the applicability of the Sommerfeld‐Maliuzhinets technique and represent a step forward to the solution of more general wedge canonical problems.
Is the mineralocorticoid receptor a potential target for stroke prevention?
Authors: Osmond Jessica M. , Rigsby Christine' S. , Dorrance Anne M.
Published: November 2007

In recent years, it has become increasingly clear that the extra-renal effects of aldosterone play an important role in the pathogenesis of cardiovascular disease. Stroke is one of the leading causes of death in the Western world, and MR (mineralocorticoid receptor) antagonism is a potential preventative therapy for patients at risk of both ischaemic and haemorrhagic strokes. This protective effect of MR antagonism appears to occur at the level of the cerebral vasculature and may be related to the expression and activation of the EGFR (epidermal growth factor receptor) and the degree of vessel wall collagen deposition.
Transgenic mice with ocular overexpression of an adrenomedullin receptor reflect human acute angle-closure glaucoma
Authors: Ittner Lars M. , Schwerdtfeger Kerstin , Kunz Thomas H. , Muff Roman , Husmann Knut , Grimm Christian , Hafezi Farhad , Lang Karl S. , Kurrer Michael O. , Götz Jürgen , Born Walter , Fischer Jan A.
Published: November 2007

Glaucoma, frequently associated with high IOP (intra-ocular pressure), is a leading cause of blindness, characterized by a loss of retinal ganglion cells and the corresponding optic nerve fibres. In the present study, acutely and transiently elevated IOP, characteristic of acute angle-closure glaucoma in humans, was observed in CLR (calcitonin receptor-like receptor) transgenic mice between 1 and 3 months of age. Expression of CLR under the control of a smooth muscle α-actin promoter in these mice augmented signalling of the smooth-muscle-relaxing peptide adrenomedullin in the pupillary sphincter muscle and resulted in pupillary palsy. Elevated IOP was prevented in CLR transgenic mice when mated with hemizygote adrenomedullin-deficient mice with up to 50% lower plasma and organ adrenomedullin concentrations. This indicates that endogenous adrenomedullin of iris ciliary body origin causes pupillary palsy and angle closure in CLR transgenic mice overexpressing adrenomedullin receptors in the pupillary sphincter muscle. In human eyes, immunoreactive adrenomedullin has also been detected in the ciliary body. Furthermore, the CLR and RAMP2 (receptor-activity-modifying protein 2), constituting adrenomedullin receptor heterodimers, were identified in the human pupillary sphincter muscle. Thus, in humans, defective regulation of adrenomedullin action in the pupillary sphincter muscle, provoked in the present study in CLR transgenic mice, may cause acute and chronic atony and, thereby, contribute to the development of angle-closure glaucoma. The CLR transgenic mice used in the present study provide a model for acute angle-closure glaucoma.
Third Graders’ Metalinguistic Skills, Reading Skills, and Stress Production in Derived English Words
Authors: Jarmulowicz Linda , Taran Valentina L. , Hay Sarah E.
Published: November 2007

Purpose

This study examined relationships between 3rd graders’ metalinguistic skills (phonological and morphological awareness), reading skills (decoding and word identification), and accurate stress production in derived words with stress-changing suffixes.

Method

Seventy-six typically developing 3rd-grade children (
M
= 8;8[years;months]) participated in a battery of tests measuring general oral language ability, phonological and morphological awareness skills, reading skills, and derived word production.

Results

Significant positive correlations between stress accuracy in derived words and all other measures were found. Two multiple regressions were run, one with stress accuracy as the outcome variable and the other with decoding as the outcome variable. Metalinguistic and decoding skills independently accounted for a significant proportion of the variance in derived word stress production beyond that accounted for by age and general oral language ability. When decoding was the outcome variable, accurate stress production explained a significant amount of variance (11%) after phonological and morphological awareness were controlled.

Conclusion

The relationship between accurate stress production and decoding appears to be strong and bidirectional. Possibly, the stress accuracy measure taps into another level of phonological awareness (i.e., morphophonological awareness), which develops later than typical segmental measures of phonological awareness.
Discoverers of giant magnetoresistance win this year’s physics nobel
Authors: Day Charles
Published: November 2007

The discovery ignited an explosion of research into how electrons flow through magnetic materials. It also boosted the storage capacity of disk drives.
Climate changes for peace prize winners
Authors: Guinnessy Paul
Published: November 2007

The award of the 2007 Nobel Peace Prize delighted scientists and the public but underscored the US government’s lack of action to reduce global warming.
String theory in the era of the Large Hadron Collider
Authors: Dine Michael
Published: November 2007

The relationship between string theory and particle experiment is more complex than the caricature presented in the popular press and weblogs.
NIX is required for programmed mitochondrial clearance during reticulocyte maturation
Authors: Schweers Rachel L. , Zhang Ji , Randall Mindy S. , Loyd Melanie R. , Li Weimin , Dorsey Frank C. , Kundu Mondira , Opferman Joseph T. , Cleveland John L. , Miller Jeffery L. , Ney Paul A.
Published: November 2007

The regulated clearance of mitochondria is a well recognized but poorly understood aspect of cellular homeostasis, and defects in this process have been linked to aging, degenerative diseases, and cancer. Mitochondria are recycled through an autophagy-related process, and reticulocytes, which completely eliminate their mitochondria during maturation, provide a physiological model to study this phenomenon. Here, we show that mitochondrial clearance in reticulocytes requires the BCL2-related protein NIX (BNIP3L). Mitochondrial clearance does not require BAX, BAK, BCL-X
L
, BIM, or PUMA, indicating that NIX does not function through established proapoptotic pathways. Similarly, NIX is not required for the induction of autophagy during terminal erythroid differentiation. NIX is required for the selective elimination of mitochondria, however, because mitochondrial clearance, in the absence of NIX, is arrested at the stage of mitochondrial incorporation into autophagosomes and autophagosome maturation. These results yield insight into the mechanism of mitochondrial clearance in higher eukaryotes. Furthermore, they show a BAX- and BAK-independent role for a BCL2-related protein in development.
Analysis of Seizure EEG in Kindled Epileptic Rats
Authors: Sen A. K. , Kubek M. J. , Shannon H. E.
Published: November 2007

Using wavelet analysis we have detected the presence of chirps in seizure EEG signals recorded from kindled epileptic rats. Seizures were induced by electrical stimulation of the amygdala and the EEG signals recorded from the amygdala were analyzed using a continuous wavelet transform. A time–frequency representation of the wavelet power spectrum revealed that during seizure the EEG signal is characterized by a chirp‐like waveform whose frequency changes with time from the onset of seizure to its completion. Similar chirp‐like time–frequency profiles have been observed in newborn and adult patients undergoing epileptic seizures. The global wavelet spectrum depicting the variation of power with frequency showed two dominant frequencies with the largest amounts of power during seizure. Our results indicate that a kindling paradigm in rats can be used as an animal model of human temporal lobe epilepsy to detect seizures by identifying chirp‐like time–frequency variations in the EEG signal.
Parameterization and R‐Peak Error Estimations of ECG Signals Using Independent Component Analysis
Authors: Chawla M. P. S.
Published: November 2007

Principal component analysis (PCA) is used to reduce dimensionality of electrocardiogram (ECG) data prior to performing independent component analysis (ICA). A newly developed PCA variance estimator by the author has been applied for detecting true, actual and false peaks of ECG data files. In this paper, it is felt that the ability of ICA is also checked for parameterization of ECG signals, which is necessary at times. Independent components (ICs) of properly parameterized ECG signals are more readily interpretable than the measurements themselves, or their ICs. The original ECG recordings and the samples are corrected by statistical measures to estimate the noise statistics of ECG signals and find the reconstruction errors. The capability of ICA is justified by finding the true, false and actual peaks of around 25–50, CSE (common standards for electrocardiography) database ECG files. In the present work, joint approximation for diagonalization of the eigen matrices (Jade) algorithm is applied to 3‐channel ECG. ICA processing of different cases is dealt with and the R‐peak magnitudes of the ECG waveforms before and after applying ICA are found and marked. ICA results obtained indicate that in most of the cases, the percentage error in reconstruction is very small. The developed PCA variance estimator along with the quadratic spline wavelet gave a sensitivity of 97.47% before applying ICA and 98.07% after ICA processing.
Do hormonal control systems produce evolutionary inertia?
Authors: Adkins-Regan Elizabeth
Published: November 2007

Hormonal control systems are complex in design and well integrated. Concern has been raised that these systems might act as evolutionary constraints when animals are subject to anthropogenic environmental change. Three systems are examined in vertebrates, especially birds, that are important for assessing this possibility: (i) the hypothalamic–pituitary–gonadal (HPG) axis, (ii) the activational effects of sex steroids on mating effort behaviour, and (iii) sexual differentiation. Consideration of how these systems actually work that takes adequate account of the brain's role and mechanisms suggests that the first two are unlikely to be impediments to evolution. The neural and molecular networks that regulate the HPG provide both phenotypic and evolutionary flexibility, and rapid evolutionary responses to selection have been documented in several species. The neuroendocrine and molecular cascades for behaviour provide many avenues for evolutionary change without requiring a change in peripheral hormone levels. Sexual differentiation has some potential to be a source of evolutionary inertia in birds and could contribute to the lack of diversity in certain reproductive (including life history) traits. It is unclear, however, whether that lack of diversity would impede adaptation to rapid environmental change given the role of behavioural flexibility in avian reproduction.
Variation in maternal effects and embryonic development rates among passerine species
Authors: Martin Thomas E , Schwabl Hubert
Published: November 2007

Embryonic development rates are reflected by the length of incubation period in birds, and these vary substantially among species within and among geographical regions. The incubation periods are consistently shorter in North America (Arizona study site) than in tropical (Venezuela) and subtropical (Argentina) South America based on the study of 83 passerine species in 17 clades. Parents, mothers in particular, may influence incubation periods and resulting offspring quality through proximate pathways, while variation in maternal strategies among species can result from selection by adult and offspring mortality. Parents of long-lived species, as is common in the tropics and subtropics, may be under selection to minimize costs to themselves during incubation. Indeed, time spent incubating is often lower in the tropical and subtropical species than the related north temperate species, causing cooler average egg temperatures in the southern regions. Decreased egg temperatures result in longer incubation periods and reflect a cost imposed on offspring by parents because energy cost to the embryo and risk of offspring predation are both increased. Mothers may adjust egg size and constituents as a means to partially offset such costs. For example, reduced androgen concentrations in egg yolks may slow development rates, but may enhance offspring quality through physiological trade-offs that may be particularly beneficial in longer-lived species, as in the tropics and subtropics. We provide initial data to show that yolks of tropical birds contain substantially lower concentrations of growth-promoting androgens than north temperate relatives. Thus, maternal (and parental) effects on embryonic development rates may include contrasting and complementary proximate influences on offspring quality and deserve further field study among species.
Introduction. Integration of ecology and endocrinology in avian reproduction: a new synthesis
Authors: Wingfield John C , Williams Tony D , Visser Marcel E
Published: November 2007

Birds are some of the most familiar organisms of global ecosystems. Changes in the visibility and abundance of birds are therefore excellent indicators of population and physiological responses to habitat changes and are a major focus for public concern about detrimental environmental changes. In order to understand how birds respond to these challenges, it is essential to determine how the environment affects reproduction under natural conditions. The continuum from environmental variables (cues) to reproductive life-history traits depends upon a cascade of neural and physiological processes that determine the extent and rate at which birds will be able to adapt to changes in their environment. For a full understanding of this ability to adapt, ecologists and endocrinologists need to collaborate and build a common framework. The objective of this theme issue is to bring together a series of papers addressing how evolutionary ecologists and endocrinologists can collaborate directly using avian reproduction as a model system. First, we address the need to integrate ecology and endocrinology and what benefits to biological knowledge will be gained. The papers collected in this issue represent a new synthesis of ecology and endocrinology as discussed in three E-BIRD workshops. The three main foci are trade-offs and constraints, maternal effects and individual variation. Authors within each group present ecological and endocrinological aspects of their topics and many go on to outline testable hypotheses. Finally, we discuss where the major problems remain and how this issue points out where these need collaborative efforts of ecologists and endocrinologists. Specific challenges are raised to future researchers to break through intellectual barriers and explore new frontiers. This framework of topics will ultimately apply to all taxa because the principles involved are universal and hopefully will have direct application to programmes integrating organisms and genes throughout biological sciences.
Hypoadiponectinemia as a Marker of Adipocyte Dysfunction—Part II: The Functional Significance of Low Adiponectin Secretion
Authors: Stern Naftali , Osher Etty , Greenman Yona
Published: November 2007

Low adiponectin expression is common in obesity and is tightly linked to insulin resistance and fat mass expansion. Whereas normal adipocytes offer effective metabolic buffering through well‐controlled release and uptake of free fatty acids on demand, adipocyte expansion induced by caloric excess and modulated by genetic, regional, and systemic factors elicits major unfavorable changes in fat cell phenotypes. Large, dysfunctional adipocytes show increased lipolysis and enhanced expression and secretion of proinflammatory and pro‐oxidative cytokines. Low adiponectin secretion is a hallmark of impaired adipocyte function; its secretion is inhibited by cytokines such as tumor necrosis factor α, interleukin 6 and plasminogen activator inhibitor 1 and by high oxidative stress induced by increased fatty acids that activate nicotinamide adenine dinucleotide phosphate‐oxidase. The ensuing hypoadiponectinemia may aggravate insulin resistance and facilitate the evolution of type 2 diabetes. Only massive weight loss allows true and sustained recovery of normal fat cell function as reflected by adiponectin secretion.
The Cardiometabolic Syndrome in Persons of the African Diaspora: Challenges and Opportunities
Authors: Schuster Dara P. , Gaillard Trudy , Osei Kwame
Published: November 2007

Unique genetic traits appear to play a role in the increased rates of hypertension (HTN), glucose dysregulation/diabetes (T2DM), and obesity in persons of African descent. Indeed, with increasing rates of westernization/urbanization and concomitant increases in obesity and T2DM, a similar predisposition to the cardiometabolic syndrome and cardiovascular disease (CVD) can be seen in Africans compared with persons of African descent, with CVD reaching epidemic proportions in many areas of Africa. In addition, the complex relationships of metabolic abnormalities that are unique to individuals of African descent have also been demonstrated in Africans. These include: (1) a dissociation of HTN to insulin resistance; (2) relative favorable lipid profile in the setting of increasing rates of CVD; (3) low levels of visceral adiposity in the setting of obesity and insulin resistance; and (4) a dissociation of insulin sensitivity and adiponectin when compared with Caucasians. Although not well understood, these unique relationships suggest that conventional parameters for CVD do not apply to Africans of persons of African descent.
Effective Subgrid Modeling From the ILES Simulation of Compressible Turbulence
Authors: Rider William J.
Published: November 2007

Implicit large eddy simulation (ILES) has provided many computer simulations with an efficient and effective model for turbulence. The capacity for ILES has been shown to arise from a broad class of numerical methods with specific properties producing nonoscillatory solutions using limiters that provide these methods with nonlinear stability. The use of modified equation has allowed us to understand the mechanisms behind the efficacy of ILES as a model. Much of the understanding of the ILES modeling has proceeded in the realm of incompressible flows. Here, we extend this analysis to compressible flows. While the general conclusions are consistent with our previous findings, the compressible case has several important distinctions. Like the incompressible analysis, the ILES of compressible flow is dominated by an effective self-similarity model (Bardina, J., Ferziger, J. H., and Reynolds, W. C., 1980, “Improved Subgrid Scale Models for Large Eddy Simulations,” AIAA Paper No. 80–1357; Borue, V., and Orszag, S. A., 1998, “Local Energy Flux and Subgrid-Scale Statistics in Three Dimensional Turbulence,” J. Fluid Mech., 366, pp. 1–31; Meneveau, C., and Katz, J., 2000, “Scale-Invariance and Turbulence Models for Large-Eddy Simulations,” Annu. Rev. Fluid. Mech., 32, pp. 1–32). Here, we focus on one of these issues, the form of the effective subgrid model for the conservation of mass equations. In the mass equation, the leading order model is a self-similarity model acting on the joint gradients of density and velocity. The dissipative ILES model results from the limiter and upwind differencing resulting in effects proportional to the acoustic modes in the flow as well as the convective effects. We examine the model in several limits including the incompressible limit. This equation differs from the standard form found in the classical Navier–Stokes equations, but generally follows the form suggested by Brenner (2005, “Navier-Stokes Revisited,” Physica A, 349(1–2), pp. 60–133) in a modification of Navier–Stokes necessary to successfully reproduce some experimentally measured phenomena. The implications of these developments are discussed in relation to the usual turbulence modeling approaches.
Rheology of tin fluorophosphate glass/polyamide 12 hybrids in the low concentration regime
Authors: Urman Kevin , Schweizer Thomas , Otaigbe Joshua U.
Published: November 2007

Phosphate glass (Pglass)/polymer hybrids are a unique material class that promises to help fulfill the growing need for new advanced materials. Rheological investigations into Pglass/polyamide 12 hybrids have shown a strong dependence on temperature and composition. Strong negative deviations from the log-additivity rule are also observed for these materials as well as a reduction in the activation energy for viscous flow. Hybrids containing <2vol.% Pglass are rheologically simple fluids that display temperature independence in plots of storage modulus versus loss modulus. Hybrids containing ≥2vol.% Pglass are rheologically complex and do not obey the time-temperature superposition principle. Through application of Han plots, we identified a structural change that occurs in hybrids containing ≥2vol.% Pglass at temperatures in excess of 220°C. This microstructural change induces an apparent yield stress in the material at these elevated temperatures. It is believed that the microstructural change is due to enhanced interactions that occur at elevated temperatures between the compatible pure components of the hybrids.
A mesoscopic rheological model of polymer/layered silicate nanocomposites
Authors: Eslami Hassan , Grmela Miroslav , Bousmina Mosto
Published: November 2007

A mesoscopic rheological model is proposed for polymer/layered silicate nanocomposites. The conformation tensors c and a are chosen to characterize states of macromolecules and silicate layers (plates), respectively. In the absence of the plates, the model reduces to the well known FENE-P model. The predictions of the model are shown to agree with thermodynamics. Other predictions of the model, obtained by solving numerically its governing equations, are responses of the suspension to transient (start-up and relaxation) and steady shear flows. The results show that the model predictions cover a wide range of the rheological behavior generally observed for polymer/layered silicate nanocomposites.
Application of a constitutive model for particulate suspensions: Time-dependent viscometric flows
Authors: Stickel Jonathan J. , Phillips Ronald J. , Powell Robert L.
Published: November 2007

Recently we proposed a constitutive model for structure and total stress in particulate suspensions, in which structural information is represented by a structure tensor that is determined from evolution equations derived from principles of continuum mechanics [Stickel et al., J. Rheol. 50, 379–413 (2006)]. The model was tested by comparing its predictions for structure and stress with results obtained from Stokesian dynamics simulations of hard-sphere suspensions in steady shear flow. Here we apply the same model to time-dependent shear flows. We compare our results with Stokesian dynamics simulations for flows with step discontinuities in the shear rate, including startup, step increases and decreases in shear rate, and flow reversal. In addition, comparisons are made with experimental results from the literature, both for shear flows with step discontinuities and sinusoidally varying shear rates. It is shown that the model predictions are in good quantitative agreement with the simulation results. The predictions also show good qualitative agreement with the experimental data. Some experimental observations, such as the plateau in the dynamic viscosity in the limit of low and high strain amplitudes, are reproduced well. In that case, the model also provides structural information that elucidates the underlying cause for the experimental observations. However, immediately after a flow reversal, the model does not capture the incomplete stress recovery, or irreversibility, that is observed experimentally.
Climate Change, Deforestation, and the Fate of the Amazon
Authors: Malhi Yadvinder , Roberts J. Timmons , Betts Richard A. , Killeen Timothy J. , Li Wenhong , Nobre Carlos A.
Published: November 2007

The forest biome of Amazonia is one of Earth's greatest biological treasures and a major component of the Earth system. This century, it faces the dual threats of deforestation and stress from climate change. Here, we summarize some of the latest findings and thinking on these threats, explore the consequences for the forest ecosystem and its human residents, and outline options for the future of Amazonia. We also discuss the implications of new proposals to finance preservation of Amazonian forests.
Switching from Repression to Activation: MicroRNAs Can Up-Regulate Translation
Authors: Vasudevan Shobha , Tong Yingchun , Steitz Joan A.
Published: November 2007

AU-rich elements (AREs) and microRNA target sites are conserved sequences in messenger RNA (mRNA) 3′ untranslated regions (3′UTRs) that control gene expression posttranscriptionally. Upon cell cycle arrest, the ARE in tumor necrosis factor–α (TNFα) mRNA is transformed into a translation activation signal, recruiting Argonaute (AGO) and fragile X mental retardation–related protein 1 (FXR1), factors associated with micro-ribonucleoproteins (microRNPs). We show that human microRNA miR369-3 directs association of these proteins with the AREs to activate translation. Furthermore, we document that two well-studied microRNAs—Let-7 and the synthetic microRNA miRcxcr4—likewise induce translation up-regulation of target mRNAs on cell cycle arrest, yet they repress translation in proliferating cells. Thus, activation is a common function of microRNPs on cell cycle arrest. We propose that translation regulation by microRNPs oscillates between repression and activation during the cell cycle.
Protolytic Equilibria and Photodegradation of Quercetin in Aqueous Solution
Authors: Momić Tatjana , Savić Jasmina , Černigoj Urh , Trebše Polonca , Vasić Vesna
Published: November 2007

Studies of protolytic equilibria and investigations of stability of flavonoids at different acidities are necessary to better understand their antioxidant efficiencies and autoxidation characteristics. The protonation constant of carbonyl group and dissociation constants of OH groups of quercetin in aqueous solutions were determined spectrophotometrically. The distribution diagram of ionic species in aqueous solutions of various acidities was calculated. Study of the effects of UV irradiation on quercetin at pH 5.00, 7.50 and 10.00 indicated that UV irradiation accelerated quercetin autoxidation via the formation of the oxidation product. The stability of quercetin and oxidation product was investigated as a function of irradiation time by using spectrophotometric and HPLC techniques. The apparent pseudofirst-order rate constants for quercetin degradation and oxidation product formation were calculated and discussed.
Running performance, not anthropometric factors, is associated with race success in a Triple Iron Triathlon
Authors: Knechtle B , Kohler G
Published: November 2007

Objectives:

To investigate the influence of anthropometric parameters on race performance in ultra-endurance triathletes.

Design:

Descriptive field study.

Setting:

The Triple Iron Triathlon Germany 2006 in Lensahn over 11.6 km swimming, 540 km cycling and 126.6 km running.

Subjects:

17 male Caucasian triathletes (mean (SD) 39.2 (7.5) years, 80.7 (8.9) kg, 178 (5) cm, BMI 25.4 (2.4) kg/m2).

Interventions:

None.

Main outcome measurements:

Determination of body mass, body height, skin fold thicknesses, circumferences of extremities, as well as calculation of body mass index (BMI), skeletal muscle mass (SM), per cent SM (%SM) and per cent body fat (%BF) in order to correlate measured and calculated anthropometric parameters with race performance.

Results:

Body mass, body height, skin fold thicknesses, circumferences of extremities, BMI, %SM and %BF had no effect (p>0.05) on race performance. No significant correlation (p>0.05) was observed between total race time and any of the directly measured and calculated anthropometric properties. A significant correlation (p<0.05) was observed between total race time and both running time (r2 = 0.87) and cycling time (r2 = 0.62). In contrast, no significant correlation (p>0.05) was shown between swimming time and total race time.

Conclusions:

There is no significant association between anthropometric parameters and race performance in ultra-endurance triathletes. Running performance rather than cycling performance seems to be the most important factor in order to be successful in a Triple Iron Triathlon. Swimming performance seems to be of low importance.
End-of-life decisions in medical practice: a survey of doctors in Victoria (Australia)
Authors: Neil D A , Coady C A J , Thompson J , Kuhse H
Published: November 2007

Objectives:

To discover the current state of opinion and practice among doctors in Victoria, Australia, regarding end-of-life decisions and the legalisation of voluntary euthanasia. Longitudinal comparison with similar 1987 and 1993 studies.

Design and participants:

Cross-sectional postal survey of doctors in Victoria.

Results:

53% of doctors in Victoria support the legalisation of voluntary euthanasia. Of doctors who have experienced requests from patients to hasten death, 35% have administered drugs with the intention of hastening death. There is substantial disagreement among doctors concerning the definition ofeuthanasia.

Conclusions:

Disagreement among doctors concerning the meaning of the termeuthanasiamay contribute to misunderstanding in the debate over voluntary euthanasia. Among doctors in Victoria, support for the legalisation of voluntary euthanasia appears to have weakened slightly over the past 17 years. Opinion on this issue is sharply polarised.
A software platform to analyse the ethical issues of electronic patient privacy policy: the S3P example
Authors: Mizani M A , Baykal N
Published: November 2007

Paper-based privacy policies fail to resolve the new changes posed by electronic healthcare. Protecting patient privacy through electronic systems has become a serious concern and is the subject of several recent studies. The shift towards an electronic privacy policy introduces new ethical challenges that cannot be solved merely by technical measures. Structured Patient Privacy Policy (S3P) is a software tool assuming an automated electronic privacy policy in an electronic healthcare setting. It is designed to simulate different access levels and rights of various professionals involved in healthcare in order to assess the emerging ethical problems. The authors discuss ethical issues concerning electronic patient privacy policies that have become apparent during the development and application of S3P.