bluuebunny/crossref_metadata_2025 huggingface dataset:
Reversal of Atrial Mechanical Stunning After Cardioversion of Atrial Arrhythmias
Authors: Sanders Prashanthan , Morton Joseph B. , Morgan John G. , Davidson Neil C. , Spence Steven J. , Vohra Jitendra K. , Kalman Jonathan M. , Sparks Paul B.
Published: September 2002

Background—

Atrial mechanical stunning develops on termination of chronic atrial arrhythmias and is implicated in the genesis of thromboembolic complications after cardioversion. The mechanisms responsible for atrial mechanical stunning are unknown. The effects of atrial rate, isoproterenol, and calcium on atrial mechanical function in patients with atrial stunning have not been evaluated, and it is not known if atrial stunning can be reversed.

Methods and Results—

Thirty-five patients with chronic atrial flutter (AFL) undergoing radiofrequency ablation were studied. Fifteen patients in sinus rhythm undergoing ablation for paroxysmal AFL were studied as control for effects of the procedure. Left atrial appendage emptying velocities (LAAEVs) and spontaneous echocardiographic contrast (LASEC) were assessed by transesophageal echocardiography during AFL, after reversion to sinus rhythm, during atrial pacing at cycle lengths of 750 to 250 ms, after a postpacing pause, and with isoproterenol or calcium. With termination of AFL, LAAEV decreased from 59.0±3.7 cm/s to 18.8±1.4 cm/s (
P
<0.0001) and LASEC grade increased from 0.9±0.1 to 2.2±0.2 (
P
<0.0001). Pacing increased LAAEV to a maximum of 38.4±3.2 cm/s (
P
<0.0001) and reduced LASEC grade to 1.9±0.2 (
P
=0.005). Isoproterenol and calcium reversed atrial mechanical stunning with LAAEV increasing to 89.3±12.6 cm/s (
P
=0.0007) and 50.2±10.5 cm/s (
P
=0.005), respectively, and LASEC grade decreasing to 0.2±0.1 (
P
=0.001) and 1.4±0.2 (
P
=0.01), respectively. The postpacing pause increased LAAEV to 69.3±3.7 cm/s (
P
<0.0001). No change in LAAEV was observed in the paroxysmal AFL group.

Conclusion—

Atrial mechanical stunning can be reversed by pacing at increased rates and through the administration of isoproterenol or calcium. These findings suggest a functional contractile apparatus in the mechanically remodeled atrium as a result of chronic atrial flutter.
Human interface and vibration control of robotic manipulator suspended from ceiling
Authors: Takahashi Yoshihiko , Yashige Makoto , Nakamura Masanori , Hirata Eiichi
Published: September 2002

A robotic manipulator, suspended from a ceiling of a general house, with an easily operated human interface and vibration-reduction control of a suspended hand, is proposed in this paper. A bedridden user can easily manipulate his/her belongings by using the robotic manipulator. The human interface is a laser pointer. When a bedridden user wishes to pick up a target object, the user exposes the target object to the laser beam spot by manipulating a joystick lever. Then, the user pushes a switch on the joystick lever. After this simple operation, the robotic hand moves automatically to the target object following a laser beam trajectory, and the user can capture the object. The robotic manipulator used in our research does not require ‘oor installation on a ‘oor because it is installed on the ceiling of a house. Two linear motion actuators are fixed on the ceiling, and the carriage is moved horizontally. The robotic hand is suspended from the carriage. An active vibration-reduction control system is designed to decrease the suspended hand vibrations. The swings of the suspended hand are detected by a hand-swing detection system using a laser position sensor. The validity of the proposed robotic manipulator has been confirmed by the experimental and simulation results.
Mechanical design and control system of robotic wheelchair with inverse pendulum control
Authors: Takahashi Yoshihiko , Ogawa Shinobu , Machida Shigenori
Published: September 2002

A robotic wheelchair with inverse pendulum control has been proposed in this paper. By using the robotic wheelchair, a wheelchair-bound person can climb over a step up to about 7 cm without a helper’s assistance. The robotic wheelchair moves on ‘at ground using four wheels. It raises its front wheels in front of a step, and maintains inverse pendulum control. A user riding can go forward and backward using his/her body inclination maintaining the inverse pendulum control. The inverse pendulum control is stopped when the front wheels proceed over a step. After the front wheels have landed on the step, the robotic wheelchair can climb over the step, assisted by d.c. motor force. In order to raise the front wheels using small d.c. motors, the robotic wheelchair can move its rear-wheel drive shafts. In this paper, the dynamics of the front-wheel raising, the mechanical designs of the robotic wheelchair, the control system of the inverse pendulum control and some of the experimental results are presented. The validity of the proposed robotic wheelchair has been confirmed by experimental results.
Addressing expressive language disorder in children who also have severe receptive language disorder: A psycholinguistic approach
Authors: Spooner Liz
Published: September 2002

This study evaluates the effectiveness of a psycholinguistic therapy programme designed to address expressive language disorder in children with complex receptive and expressive language difficulties. The two subjects were aged 6.03 and 9.09 years and attended a language unit in a mainstream school. Language samples from each subject were obtained using formal tests. These were analysed to provide a baseline. Subjects then carried out a therapy programme designed using principles of a psycholinguistic model of sentence production. Assessments were repeated to determine whether therapy had been effective. Results indicated that subjects had made significant progress in the structure and content of their expressive language.
Middle cerebral artery to umbilical artery resistance index ratio in the prediction of neonatal outcome
Authors: Makhseed M , Jirous J , Ahmed M.A , Viswanathan D.L
Published: September 2002

Objective: The objectives of this study were to evaluate the usefulness of the middle cerebral artery to umbilical artery resistance index ratio (C/U ratio) as a predictor of adverse perinatal outcome, and to show that the absence of fetal umbilical artery end‐diastolic velocity (AEDV) in SGA fetuses is associated with high morbidity and mortality. Method: In this prospective study, color Doppler flow imaging was used for the estimation of the C/U ratio in fetuses that were small for their gestational age, in 70 singleton pregnancies between 29 and 42 weeks of gestation. The subjects were categorized into two groups, with Group A consisting of 35 small for gestational age (SGA) fetuses with a normal C/U ratio (1.05 or higher), and Group B comprising 35 SGA fetuses with an abnormal C/U ratio (below 1.05). Result: The mean C/U ratio values for birth weight and gestational age were higher in group A than in group B. Fetuses born to mothers in group B stayed longer in the neonatal special care unit (NSCU), whereas the period from ultrasound examination to delivery was higher in the cases in group A. A higher percentage of mothers with an abnormal C/U ratio underwent cesarean section. Fetuses with an absent end‐diastolic velocity of the umbilical artery had a higher morbidity. Three stillbirths occurred in fetuses with an absent end‐diastolic velocity of the umbilical artery. Conclusion: Our results suggest that the C/U ratio is a good predictor of neonatal outcome, and could be used to identify fetuses at risk of morbidity and mortality. Fetal umbilical artery AEDV with intrauterine growth restriction is associated with high perinatal morbidity and mortality.
Low pulse oxygen saturation in post‐menopausal women at high altitude is related to a high serum testosterone/estradiol ratio
Authors: Gonzales G.F , Villena A
Published: September 2002

Objective: The present study was designed to determine if low pulse oxygen saturation (Spo2) in post‐menopausal women at high altitude was related to high serum testosterone/estradiol (T/E2) ratio. Method: Studies were carried out in 191 women living in Cerro de Pasco, Peru (4340 m above sea level) and in 56 women living in Lima (150 m asl). Body weight, height, Spo2, hematocrit, serum follicle stimulating hormone (FSH), T and E2 levels were measured in all women. Body mass index (BMI), menopausal status and serum T/E2 ratio were calculated from data. Result: At high altitude, the values of Spo2, serum T, and serum E2 were significantly lower in post‐menopausal than in pre‐menopausal women. Hematocrit, serum FSH levels, and serum T/E2 ratios were significantly higher in post‐menopausal women. Serum T and E2 levels, T/E2 ratio, Spo2, and hematocrit levels were not further changed with time after menopause. Women with Spo2<85% had lower serum E2, a higher serum T/E2 ratio, and higher hematocrit values than women with Spo2>90%. At high altitude, multiple regression analysis showed that low Spo2 was related to menopausal status (−2.6±0.83; β±S.E.; P<0.002) and not to chronological age (−0.06±0.04; P: NS). Further analysis showed that low Spo2 was related to high basal serum FSH levels and a high serum T/E2 ratio in the presence of an interaction between FSH and T/E2. Conclusion: Low values of Spo2 in women at high altitude were related to a high T/E2 ratio.
Arteriovenous malformations of the uterus associated with medical abortion
Authors: Wiebe E.R. , Switzer P.
Published: September 2002

Seven cases of uterine arteriovenous malformations associated with pregnancy were initially suspected by the history of prolonged bleeding after a medical abortion and then confirmed by color Doppler scanning. All cases were managed expectantly and resolved spontaneously. When AVMs required diagnosis by pathology or angiography, only the most severe cases would have been reported. Now that they can be recognized on ultrasound, it is possible that mild cases such as these will be found to be much more common.
Decision‐directed hysterectomy: a possible approach to improve medical and economic outcomes
Authors: Kovac S.R.
Published: September 2002

Objective: This study was undertaken to determine if the use of formal guidelines in selecting the route of hysterectomy would improve medical and economic outcomes. Method: Data from 4595 hysterectomies performed at a single center in women whose primary diagnosis were unrelated to invasive cancer or pregnancy were analyzed in terms of mean, uterine weight, costs, length of stay, and complications. Results: When formal guidelines were used to determine the route of hysterectomy, vaginal hysterectomy was performed in 90% of the patients treated and in 100% of the patients in whom the pathology was confined to the uterus. In comparison, when formal guidelines were not incorporated in the decision‐making process, vaginal hysterectomy was performed in 42% of the patients treated and in 64% of the patients in whom the pathology was confined to the uterus. Conclusions: Using these or similar guidelines to assist in clinical decision making would have resulted in a potential savings of US$1 184 000 for every 1000 hysterectomies performed at the institution where this study was undertaken and would have freed up 1020 patient‐bed days and reduced complications by approximately 20%.
Tectonic and climatic controls on a Mesozoic forearc
basin succession, Alexander Island, Antarctica
Authors: NICHOLS GARY J. , CANTRILL DAVID J.
Published: September 2002

The Cretaceous Fossil Bluff Group on Alexander Island, on the west side of the Antarctic
Peninsula, contains a remarkably complete record of the evolution of a forearc basin. The latest
(Aptian–Albian) stages in the basin history are recorded in a well-exposed succession at the southern
end of the island, where a series of nunataks provide exposure of over a thousand metres of shallow
marine and continental deposits. An abrupt facies shift from upper shoreface marine facies to braided
fluvial deposits is interpreted as the record of regional uplift in the volcanic arc. This event coincides
with the Palmer Land deformation event which may be related to a mid-Cretaceous mantle plume. A
gradual reduction in depositional gradient and a return to shallow marine conditions towards the top
of the exposed section is interpreted as a consequence of erosion of the arc and subsidence within the
basin. Palaeocurrent data and facies distributions indicate that the continental deposits formed a fan-shaped
wedge at least 30 km in diameter in the southern part of the forearc basin. Fossil plants indicate
that the palaeoclimate was warm and humid throughout the period of deposition. Mapping and
facies analysis of the upper part of the Fossil Bluff Group in southern Alexander Island has resulted
in a revision of the stratigraphic terminology for the area. The Triton Point Member, formerly part of
the Neptune Glacier Formation, has been raised to formation status and two members (the Citadel
Bastion Member and the Coal Nunatak Member) and a Bed (the Upper Coal Nunatak Sandstone
Bed) are defined here within the formation.
The magmatic evolution of the late Miocene
laccolith–pluton–dyke granitic complex of Elba Island, Italy
Authors: DINI A. , INNOCENTI F. , ROCCHI S. , TONARINI S. , WESTERMAN D. S.
Published: September 2002

Since late Miocene time, post-collisional extension of the internal parts of the Apennine
orogenic belt has led to the opening of the Tyrrhenian basin. Extensive, mainly acidic peraluminous
magmatism affected the Tuscan Archipelago and the Italian mainland during this time, building up
the Tuscan Magmatic Province as the fold belt was progressively thinned, heated and intruded by
mafic magmas. An intrusive complex was progressively built on western Elba Island by emplacement,
within a stack of nappes, of multiple, shallow-level porphyritic laccoliths, a major pluton, and a final
dyke swarm, all within the span from about 8 to 6.8 Ma. New geochemical and Sr–Nd isotopic investigations
constrain the compositions of materials involved in the genesis of the magmas of Elba Island
compared to the whole Tuscan Magmatic Province. Several distinct magma sources, in both the crust
and mantle, have been identified as contributing to the Elba magmatism as it evolved from crust-, to
hybrid-, to mantle-dominated. However, a restricted number of components, geochemically similar to
mafic K-andesites of the Island of Capraia and crustal melts like the Cotoncello dyke at Elba,
are sufficient to account for the generation by melt hybridization of the most voluminous magmas
(c. εNd(t) −8.5, 87Sr/86Sr 0.715). Unusual magmas were emplaced at the beginning and end of the
igneous activity, without contributing to the generation of these hybrid magmas. These are represented
by early peraluminous melts of a different crustal origin (εNd(t) between −9.5 and −10.0, 87Sr/86Sr variable between 0.7115 and 0.7146), and late mantle-derived magma strongly enriched in
incompatible elements (εNd(t) = −7.0, 87Sr/86Sr = 0.7114) with geochemical–isotopic characteristics
intermediate between contemporaneous Capraia K-andesites and later lamproites from the Tuscan
Magmatic Province. Magmas not involved in the generation of the main hybrid products are not volumetrically
significant, but their occurrence emphasizes the highly variable nature of crust and mantle
sources that can be activated in a short time span during post-collisional magmatism.
MARITAL ASSORTMENT FOR GENETIC SIMILARITY
Authors: ECKMAN RONAEL E. , WILLIAMS ROBERT , NAGOSHI CRAIG
Published: September 2002

The present study involved analyses of a Caucasian American sample (n=949) and a Japanese American sample (n=400) for factors supporting Genetic Similarity Theory (GST). The analyses found no evidence for the presence of genetic similarity between spouses in either sample for the blood group analyses of nine loci. All results indicated random mating for blood group genes. The results did not provide consistent substantial support to show that spousal similarity is correlated with the degree of genetic component of a trait for a set of seventeen individual differences variables, with only the Caucasian sample yielding significant correlations for this analysis. A third analysis examining the correlation between presence of spousal genetic similarity and spousal similarity on observable traits was not performed because spousal genetic similarity was not observed in either sample. The overall implication of the study is that GST is not supported as an explanation for spousal similarity in humans.
DETERMINANTS OF COITAL FREQUENCY AMONG MARRIED WOMEN IN CENTRAL AFRICAN REPUBLIC: THE ROLE OF FEMALE GENITAL CUTTING
Authors: STEWART HOLLEY , MORISON LINDA , WHITE RICHARD
Published: September 2002

This paper examines determinants of one aspect of sexual behaviour – coital frequency – among 2188 married women in the Central African Republic using a secondary analysis of data from the Demographic and Health Survey of 1994–95. Female genital cutting (or circumcision) is practised in the Central African Republic and self-reported circumcision status was included in the questionnaire enabling it to be examined as a possible determinant of coital frequency. Multiple logistic regression was used to find a subset of factors independently associated with coital frequency. Decreased coital frequency was found in those who had longer duration of marriage, those who were not the most recent wife in a polygamous marriage and those who had more surviving children. Coital frequency was higher in more educated women and those not contracepting because they wanted to get pregnant. After adjusting for confounders no association between female genital cutting and coital frequency was found. The extent to which women can control coital frequency in this culture is not known and fertility desires may override any negative effects of circumcision on sexual pleasure. It was therefore not possible to draw conclusions about how female genital cutting affects a woman’s desire for sexual intercourse and consequently there is a need to develop research methods further to investigate this question.
Reflection of circumferential modes in a choked nozzle
Authors: STOW S. R. , DOWLING A. P. , HYNES T. P.
Published: September 2002

Small perturbations of a choked flow through a thin annular nozzle are investigated.
Two cases are considered, corresponding to a ‘choked outlet’ and a ‘choked inlet’
respectively. For the first case, either an acoustic or entropy or vorticity wave is
assumed to be travelling downstream towards the nozzle contraction. An asymptotic
analysis for low frequency is used to find the reflected acoustic wave that is created.
The boundary condition found by Marble & Candel (1977) for a compact choked
nozzle is shown to apply to first order, even for circumferentially varying waves. The
next-order correction can be expressed as an ‘effective length’ dependent on the mean
flow (and hence the particular geometry of the nozzle) in a quantifiable way.

For the second case, an acoustic wave propagates upstream and is reflected from a
convergent–divergent nozzle. A normal shock is assumed to be present. By considering
the interaction of the shock's position and flow perturbations, the reflected propagating
waves are found for a compact nozzle. It is shown that a significant entropy
disturbance is produced even when the shock is weak, and that for circumferential
modes a vorticity wave is also present. Numerical calculations are conducted using a
sample geometry and good agreement with the analysis is found at low frequency in
both cases, and the range of validity of the asymptotic theory is determined.
On nonlinear convection in mushy layers
Part 1. Oscillatory modes of convection
Authors: RIAHI D. N.
Published: September 2002

We consider the problem of nonlinear convection in horizontal mushy layers during
the solidification of binary alloys. We analyse the oscillatory modes of convection
in the form of two- and three-dimensional travelling and standing waves. Under a
near-eutectic approximation and the limit of large far-field temperature, we determine
the solutions to the nonlinear problem by using a perturbation technique, and the
stability of two- and three-dimensional solutions in the form of simple travelling
waves, general travelling waves and standing waves is investigated. The results of the
stability and the nonlinear analyses indicate that supercritical simple travelling rolls
are stable over most of the studied range of parameter values, while supercritical
standing rolls can be stable only over some small range of parameter values, where
the simple travelling rolls are unstable. The results of the investigation of the onset
of plume convection and chimney formation leading to the occurrence of freckles in
the alloy crystal indicate that the chimney of the plume can be generated internally
or near the lower boundary of the mushy layer. The roles of a Stefan number, a
permeability parameter and a concentration ratio on the flow instability in both linear
and nonlinear regimes are also determined.
The orexins/hypocretins: hypothalamic peptides linked to sleep and appetite
Authors: TAHERI SHAHRAD , HAFIZI SEPEHR
Published: September 2002

The orexins/hypocretins are novel neuropeptides synthesized by neurons whose cell bodies are located in the lateral hypothalamus. Although these neurons are few in number, they send projections widely throughout the central nervous system (Kilduff & Peyron, 2000). There has been great excitement about the orexins/hypocretins from both the scientific and medical community. These peptides are remarkable in that they were discovered using state-of-the-art molecular techniques before their physiological actions were studied. Furthermore, there has been an exponential progress in our scientific knowledge of these peptides culminating in the orexins/hypocretins being linked to the sleep disorder, narcolepsy. With the importance of the orexins/hypocretins in sleep and arousal being increasingly recognized, it is likely that these peptides are altered by or contribute to several medical and psychiatric disorders.
Decreased cerebral haemodynamic response to cognitive and physiological tasks in mood disorders as shown by near-infrared spectroscopy
Authors: MATSUO, K. , KATO N. , KATO T.
Published: September 2002

Background. Hypofrontality has been demonstrated in mood disorders by functional brain imaging methods such as positron emission tomography. However, the neurobiological basis of hypofrontality has not been well clarified. Near-infrared spectroscopy (NIRS) is a non-invasive technique for continuous monitoring of alterations in oxygenated (oxyHb) and deoxygenated (deoxyHb) haemoglobin using near-infrared light, which penetrates biological tissues.

Methods. We used NIRS during cognitive and physiological tasks to investigate alterations of haemoglobin oxygenation in the frontal region of euthymic patients with mood disorders (major depressive disorder (MD) and bipolar disorder (BP)) and in controls.

Results. The increase of oxyHb during a verbal fluency task was significantly less in the MD and the BP groups than in the controls. The MD group showed a significantly smaller decrease of oxyHb during hyperventilation than the controls. The BP group also showed a similar trend.

Conclusions. These findings suggest that the hypofrontality in mood disorders may be associated with a poor response in the cerebral blood vessels to neuronal and chemical stimuli.
Does sexual violence contribute to elevated rates of anxiety and depression in females?
Authors: FERGUSSON, D. M. , SWAIN-CAMPBELL N. R. , HORWOOD L. J.
Published: September 2002

Background. It is well documented that females have higher rates of internalizing disorders (anxiety, depression) than males. It is also well known that females have higher exposure to childhood sexual abuse and sexual assault. Recently, it has been proposed that the higher levels of internalizing disorders in females may be caused by their greater exposure to sexual violence.

Method. Data were gathered as part of the Christchurch Health and Development Study. In this study a cohort of 1265 children born in Christchurch, New Zealand, in 1977 have been studied from birth to age 21 years. The measures collected included: major depression and anxiety, childhood sexual abuse and adolescent sexual assault.

Results. Findings confirmed the established conclusion that internalizing disorders are over twice as common in females than males (ORs 2·2–2·7). In addition, it was found that females were exposed to higher rates of sexual violence than males (ORs 5·1–8·4). Statistical control for gender related differences in exposure to sexual violence reduced the associations between gender and anxiety and depression. Nonetheless, even after such control, gender was significantly (P<0·0001) related to both anxiety (OR = 1·8; 95% CI, 1·3–2·4) and depression (OR = 1·9; 95% CI, 1·4–2·3).

Conclusions. Greater female exposure to sexual violence may be a factor that contributes to greater female susceptibility to internalizing disorders. However, even after adjustment for gender differences in exposure to sexual violence it is clear that a substantial relationship between gender and internalizing disorder persists.
Hypothalamic–pituitary–adrenal axis function in patients with chronic depression
Authors: WATSON S. , GALLAGHER P. , DEL-ESTAL D. , HEARN A. , FERRIER I. N. , YOUNG A. H.
Published: September 2002

Background. Hypothalamic–pituitary–adrenal (HPA) axis function in patients with chronic depression has previously been shown to be normal when measured using the dexamethasone suppression test (DST). We examined patients with chronic depression using the sensitive dexamethasone/corticotropin releasing hormone (dex/CRH) test and the dexamethasone suppression test (DST) to establish whether HPA axis abnormalities are present in this group. We also compared the sensitivity of the two tests and compared the results with previous studies in depression that have not specifically selected chronic patients.

Method. Twenty-nine patients with the chronic subtype of major depressive disorder and 28 matched controls underwent examination of HPA axis function.

Results. Neither the cortisol response to the DST or the dex/CRH test differed significantly between the patient and control groups. There was a trend in favour of more patients than controls having an abnormal response to the dex/CRH test (P = 0.052). Neither the patients with an abnormally enhanced response, nor the magnitude of response could be predicted by any illness or demographic variable.

Conclusion. The HPA axis is not overtly abnormal in chronic depression. This contrasts with previous findings in acute depression and bipolar disorder and may suggest that the HPA axis abnormalities present in acute depression resolve, but are not accompanied by symptom resolution. Alternatively, a subgroup of depressives with less HPA dysfunction may progress to chronicity. This has implications for treatment and prognosis. The dex/CRH is a more sensitive test of HPA axis function than the DST in patients with chronic depression.
Thermal dissipation, leaf rolling and inactivation of PSII reaction centres in Amomum villosum
Authors: Feng Yu-Long , Cao Kun-Fang , Feng Zhi-Li
Published: September 2002

Amomum villosum Lour. (Zingiberaceae) is an obligate shade plant. Its leaves naturally roll up upon exposure to bright sun. This paper characterizes the effects of its leaf rolling and light on photoinhibition of photosynthesis and thermal dissipation activity under field conditions with sufficient soil moisture. Between the plants from bright and shaded parts of a canopy gap, both maximum photosynthetic rate (mean ≈ 6.5 μmol m-2 s-1) and stomatal conductance (148 vs. 131 mmol m-2 s-1) were not significantly different, but apparent quantum yield (0.021 vs. 0.025) and dark respiration rate (0.49 vs. 0.30 μmol m-2 s-1) were. In the foggy morning, when the incident irradiance was low, photoinhibition had already occurred in plants in the bright part of the canopy gap and also in plants in the shaded part of the gap but to a much lesser degree. Photoinhibition accelerated with increase of incident irradiance and relaxed in the afternoon. Thermal dissipation as indicated by non-photochemical fluorescence quenching (NPQ) increased rapidly in the morning and continued at a high rate in the afternoon. Prevention of leaf rolling resulted in acceleration of photoinhibition. Artificial inhibition of the xanthophyll cycle led to acceleration of both photoinhibition and inactivation of PSII reaction centres, and decrease of NPQ. Photoinhibited leaves in either control or treatment plants recovered overnight. These results show that A. villosum is able effectively to prevent photodamage through the mechanisms of leaf rolling, thermal dissipation and reversible inactivation of PSII reaction centres.
Two biases in estimating range sizes of Amazonian plant species
Authors: Ruokolainen Kalle , Tuomisto Hanna , Vormisto Jaana , Pitman Nigel
Published: September 2002

The Amazonian rain forests form one of the largest areas of continuous forest
in the world, and they harbour a substantial part of the world's biodiversity (World Conservation Monitoring Centre 1992). The extravagant species richness of Amazonia makes collecting information on species distribution patterns there a formidable challenge. Relatively few studies have been able to provide data that cover both a large enough number of species and wide enough geographical areas to allow relevant biogeographical and ecological generalizations (such studies concerning plants include Balslev 1988, de Oliveira & Daly 1999, Pitman et al. 1999, Prance 1973, ter Steege et al. 2000, Terborgh & Andresen 1998, Tuomisto & Poulsen 1996). The scarcity of field observations is undoubtedly one of the reasons why very different ideas exist about the mechanisms that control plant distributions and patterns of species richness in Amazonia (Balslev 1988, Condit 1996, Gentry 1988, Nelson et al 1990, Pitman et al. 1999, Prance 1973, 1982; ter Steege et al. 2000, Tuomisto et al. 1995).
The semiotics of symmetry, or Rimsky-Korsakov's operatic history lesson
Authors: MORRISON SIMON
Published: September 2002

Rimsky-Korsakov dwelled at length on his place in music history. His musings informed his creative processes, notably his handling of operatic time and space relationships. His stage works rely on structural and syntactic reflection rather than patterns of cause and effect for cohesion. This article examines the narrative contents of Sadko (1896), a setting of the merchant tale ‘‘Sadko the Rich Trader” that follows the contours of the Orpheus parable. The analysis, focusing on the mirror relationships between Russians and non-Russians, indicates that the composer conceived the score as a parody of nationalism and orientalism. In depicting self as other and other as self, Sadko also demonstrates the inherent universality, rather than the inherent Russianness, of Rimsky-Korsakov’s music.
Genres and techniques of soundscape composition as developed at Simon Fraser University
Authors: Truax Barry
Published: September 2002

The soundscape composition, as pioneered at Simon Fraser University since the early 1970s, has evolved rapidly to explore a full range of approaches from the ‘found sound’ representation of acoustic environments through to the incorporation of highly abstracted sonic transformations. The structural approaches similarly range from being analogues of real-world experience, such as listening from a fixed spatial perspective or moving through a connected series of acoustic spaces, to those that mirror both nonlinear mental experiences of memory recall, dreams, and free association, as well as artificial sonic constructs made familiar and possible by modern ‘schizophonic’ audio techniques of sonic layering and embedding. The octophonic surround-sound playback format as used in contemporary soundscape presentations has achieved a remarkable sense of immersion in a recreated or imaginary sonic environment. Specific works realised at SFU are analysed that illustrate each of these approaches.
Alien intimacies: hearing science fiction narratives in Hildegard Westerkamp's
Cricket Voice (or ‘I don't like the country, the crickets make
me nervous’)
Authors: McCartney Andra
Published: September 2002

This paper discusses listener responses to a contemporary soundscape composition based on the sound of a cricket. Soundscape composers make works based on everyday sounds and sound environments, usually recorded by themselves (Truax 1984, 1996). While the composer of this piece aims to bring listeners closer to the sounds around them by creating audio pieces based on these sounds (Westerkamp 1988), some listeners feel fear and anxiety rather than the heightened closeness and understanding that she wishes listeners to experience. I compare the sound structure of Cricket Voice with close listening to excerpts of the film soundtrack of Ridley Scott's Alien as well as a short excerpt from the soundtrack of the X Files, discussing how science fiction film and television soundtracks index sonic intimacy with different intent from that of Westerkamp, and raising questions about how such approaches to intimacy might simultaneously reflect and intensify urban anxieties about the sounds of ‘alien’ species that are associated with wilderness environments.
Linking soundscape composition
and acoustic ecology
Authors: Westerkamp Hildegard
Published: September 2002

1. EXPLORING THE CONNECTION

The term soundscape composition did not exist when I started composing with environmental sounds in the mid-1970s. Through a variety of fortunate circumstances and because of what the 1970s were in Vancouver and Canada - artistically inspiring and moneys were available for adventurous and culturally, socially, politically progressive projects - I had discovered that environmental sounds were the perfect compositional ‘language’ for me. I had learnt much while working with the World Soundscape Project at Simon Fraser University, about listening, about the properties of sound, about noise, the issues we face regarding the quality of the sound environment and much more. This in combination with learning to record and to work with analog technology in the sonic studio allowed me to speak with sound in a way I found irresistible. In addition, the start-up of Vancouver Co-operative Radio gave us the - at that time rare - opportunity to broadcast our work. It was a place where cultural exploration and political activism could meet. It was from within this exciting context of ecological concern for the soundscape and the availability of an alternate media outlet that my compositional work - now often called soundscape composition - emerged. And it came as a surprise to me, as I had never thought of composing nor of broadcasting as a professional choice in my life.
Composing with the Soundscape of Jones Street
Authors: Weidenaar Reynold
Published: September 2002

This article traces the audio production and soundscape composition for a multimedia work for any solo instrument, colour video, and digital sound. There is an account of earlier soundscape recordings of the Brooklyn Bridge. A description of the visual images of Jones Street is followed by a portrayal of the street life and consequent soundscape. There is a report on stereo recording techniques, the sounds that were gathered, and the sounds that were selected as source material. A discussion of philosophical and aesthetic considerations precedes a detailed explanation of the digital processing and composing methods.
Priority conservation areas for birds in El Salvador
Authors: Komar Oliver
Published: September 2002

El Salvador has the smallest protected areas system in Central America. High levels of habitat destruction and disturbance throughout the country make the reserve system especially important for conservation of biodiversity. I used complementarity approaches to assess the relative conservation importance of ten reserves in El Salvador. The principal criterion was presence of nationally threatened and endangered bird species. Additional criteria included residency status (resident species were more important than migratory non‐breeding species) and regionally endemic species. Montecristo National Park was the most important area, with 42% of all nationally threatened birds present. El Imposible National Park, El Salvador's largest park (5000 ha), scored second, followed by Laguna El Jocotal wildlife refuge and Barra de Santiago wildlife refuge. In all, these four areas provide refuge for 83% of El Salvador's 268 nationally threatened bird species in less than 7600 ha of natural habitat. Because of small reserve sizes, all of El Salvador's threatened birds may need additional protection.
Measuring genetic diversity in translocation programmes: principles and application to a chimpanzee release project
Authors: Goossens Benoît , Funk Stephan M. , Vidal Carmen , Latour Stéphanie , Jamart Aliette , Ancrenaz Marc , Wickings Elisabeth J. , Tutin Caroline E. G. , Bruford Michael W.
Published: September 2002

Logging and poaching have dramatically reduced chimpanzee density and distribution in the Republic of Congo. Most chimpanzee translocations attempted in the past failed because a number of biological and non‐biological factors can influence success. Biological considerations include knowledge of behaviour, disease, habitat requirements and genetics. We critically review genetic considerations in pre‐ and post‐release phases of translocations and apply them to a welfare‐based chimpanzee release project in the Republic of Congo which aimed to re‐establish orphan chimpanzees in the wild with a native chimpanzee population. We analyze genetic diversity and relatedness in released animals and devise a genotyping strategy for monitoring of released individuals and their future offspring. Fifty‐nine confiscated chimpanzees from different areas of the Republic of Congo were typed for 20 microsatellites using plucked hair as the DNA source. Genetic diversity was high, with an average expected heterozygosity of 81%, and three to 18 alleles per locus. Between 1996 and 1998, 19 individuals were released, and genetic analysis showed that these are unrelated (mean r± jack‐knifed SD =−0.014 ± 0.001). Using FST and population admixture analysis, we identified population structure in wild chimpanzees. For long‐term genetic monitoring of released and native chimpanzees, we identified a set of six informative markers, which are easy to score using basic techniques.
Declines in the numbers of amateur and professional taxonomists: implications for conservation
Authors: Hopkins G. W. , Freckleton R. P.
Published: September 2002

To ensure the effective conservation of biodiversity the distribution of species needs to be accurately characterized and areas of high species richness located. For many taxa this can be achieved only by experienced taxonomists. Taxonomic research has a large input from non‐professional or amateur researchers, in addition to professionals working at museums or universities. The decline of taxonomy and the number of taxonomists within the professional community has been widely publicized, but the trends in the activities of amateur taxonomists are unclear. Because amateurs contribute many valuable records of species occurrence this may have a disproportionate impact upon the information available for conservation planning and represents an underappreciated threat to conservation planning. We use taxonomic research by UK entomologists in order to evaluate the changing role of both amateur and professional taxonomists. We reviewed contributions by British‐based authors to Entomologist's Monthly Magazine over the past century. Our results show that both amateur and professional taxonomy have undergone a long and persistent decline since the 1950s, in terms of both the number of contributors and the number of papers contributed. It is argued that the conservation community needs to help try and reverse the decline of taxonomy.
Interactions of ATP, oestradiol, genistein and the anti-oestrogens, faslodex (ICI 182780) and tamoxifen, with the human erythrocyte glucose transporter, GLUT1
Authors: AFZAL Iram , CUNNINGHAM Philip , NAFTALIN Richard. J.
Published: September 2002

17β-Oestradiol (ED when subscript to K) and the phytoestrogen isoflavone genistein (GEN) inhibit glucose transport in human erythrocytes and erythrocyte ghosts. The selective oestrogen receptor modulators or anti-oestrogens, faslodex (ICI 182780) (FAS) and tamoxifen (TAM), competitively antagonize oestradiol inhibition of glucose exit from erythrocytes (Ki(ED/FAS) = 2.84±0.16μM and Ki(ED/TAM) = 100±2nM). Faslodex has no significant inhibitory effect on glucose exit, but tamoxifen alone inhibits glucose exit (Ki(TAM) = 300±100nM). In ghosts, ATP (1–4mM) competitively antagonizes oestradiol, genistein and cytochalasin B (CB)-dependent inhibitions of glucose exit, (Ki(ATP/ED) = 2.5±0.23mM, Ki(ATP/GEN) = 0.99±0.17mM and Ki(ATP/CB) = 0.76±0.08mM). Tamoxifen and faslodex reverse oestradiol-dependent inhibition of glucose exit with ATP>1mM (Ki(ED/TAM) = 130±5nM and Ki(ED/FAS) = 2.7±0.9μM). The cytoplasmic surface of the glucose transporter (GLUT)1 contains four sequences with close homologies to sequences in the ligand-binding domain of human oestrogen receptor β (hesr-2). One homology is adjacent to the Walker ATP-binding motif II (GLUT1, residues 225–229) in the large cytoplasmic segment linking transmembrane helices 6 and 7; another GLUT (residues 421–423) contains the Walker ATP-binding motif III. Mapping of these regions on to a three-dimensional template of GLUT indicates that a possible oestrogen-binding site lies between His337, Arg349 and Glu249 at the cytoplasmic entrance to the hydrophilic pore spanning GLUT, which have a similar topology to His475, Glu305 and Arg346 in hesr-2 that anchor the head and tail hydroxy groups of oestradiol and genistein, and thus are suitably placed to provide an ATP-sensitive oestrogen binding site that could modulate glucose export.
Molecular mapping of the determinants involved in human Staufen–ribosome association
Authors: LUO Ming , DUCHAÎNE Thomas F. , DesGROSEILLERS Luc
Published: September 2002

The human double-stranded (ds) RNA-binding protein Staufen (hStau) is considered to have a role in RNA transport and its localization. By using sedimentation analysis on sucrose gradients, we showed that the Staufen isoform with an apparent molecular mass of 55kDa (Stau55) co-fractionated with ribosomes and associated with both the 40 and 60S ribosomal subunits, suggesting that the Staufen isoform hStau55 plays some role in translation. To map the determinant(s) involved in this association, we generated a series of deletion mutants and analysed their subcellular distribution by cell fractionation and fluorescent immunomicroscopy. Our results demonstrated that multiple determinants promote hStau55—ribosome association via both an RNA-binding-dependent mechanism and protein—protein interaction. The RNA-binding activity of the ds RNA-binding protein domain 3 (dsRBD3) but not that of dsRBD4 is the first determinant. Although necessary for stable association with ribosomes, dsRBD3 alone is not sufficient and needs other determinants as co-factors. Consistently, when expressed together, dsRBD4 and the tubulin-binding domain constitute the minimal Stau55/ribosome protein—protein association domain. This region of Stau55 is sufficient to associate with ribosomes independently, but requires the RNA-binding activity of dsRBD3 for complete association. Thus the results are consistent with a putative role for Stau55 in the regulation of translation.
C-terminal domain of rodent intestinal mucin Muc3 is proteolytically cleaved in the endoplasmic reticulum to generate extracellular and membrane components
Authors: WANG Rongquan , KHATRI Ismat A. , FORSTNER Janet F.
Published: September 2002

Although human MUC3 and rodent Muc3 are both membrane-associated intestinal mucins, the present study has explored the possibility that rodent Muc3 might exist in soluble as well as membrane forms. No evidence was obtained for the existence of soluble splice variants; however, experiments with heterologous cells transfected with cDNA encoding the 381-residue C-terminal domain of rodent Muc3 showed that a definitive proteolytic cleavage occurs during processing in the endoplasmic reticulum. The products consisted of a V5-tagged 30kDa extracellular glycopeptide and a Myc-tagged 49kDa membrane-associated glycopeptide. Throughout their cellular transport to the plasma membrane, the two fragments remained associated by non-covalent SDS-sensitive interactions. Site-specific mutagenesis pinpointed the need for glycine and serine residues in the cleavage sequence Leu-Ser-Lys-Gly-Ser-Ile-Val-Val, which is localized between the two epidermal-growth-factor-like motifs of the mucin. A similar cleavage sequence (Phe-Arg-Pro-Gly↓Ser-Val-Val-Val, where ↓ signifies the cleavage site) has been reported in human MUC1 and analogous sites are present in human MUC3, MUC12 and MUC17. Thus early proteolytic cleavage may be a conserved characteristic of many membrane-associated mucins, possibly as a prelude to later release of their large extracellular domains at cell surfaces.
Theoretical study of the photoelectron spectrum of NO3 and the excited states of NO3+. I. Electronic spectrum
Authors: Eisfeld Wolfgang , Morokuma Keiji
Published: September 2002

The photoelectron spectroscopy of NO3 is of considerable interest, particularly because of the radical’s relevance in atmospheric chemistry, but recent studies gave controversial results. In the current study we present high-level ab initio calculations of the vertical and adiabatic electronic spectrum of NO3+ and the photoelectron spectrum of the radical. The vertical ionization spectrum up to 18 eV was calculated by complete active space self-consistent field and multireference configuration interaction methods, using extended basis sets. For D3h geometries 15 ionic singlet and triplet states are found and characterized within this energy range, of which only the lowest four are due to principal ionization. For geometries of lower symmetry these states split into 23 states, of which seven correspond to principal ionizations. Equilibrium geometries and harmonic frequencies were computed for the controversial higher principal ionizations, and adiabatic ionization potentials were obtained. These results disagree in several points with previous experiments and their interpretation, which is discussed in detail.
Unknown quantum states: The quantum de Finetti representation
Authors: Caves Carlton M. , Fuchs Christopher A. , Schack Rüdiger
Published: September 2002

We present an elementary proof of the quantum de Finetti representation theorem, a quantum analog of de Finetti’s classical theorem on exchangeable probability assignments. This contrasts with the original proof of Hudson and Moody [Z. Wahrschein. verw. Geb. 33, 343 (1976)], which relies on advanced mathematics and does not share the same potential for generalization. The classical de Finetti theorem provides an operational definition of the concept of an unknown probability in Bayesian probability theory, where probabilities are taken to be degrees of belief instead of objective states of nature. The quantum de Finetti theorem, in a closely analogous fashion, deals with exchangeable density-operator assignments and provides an operational definition of the concept of an “unknown quantum state” in quantum-state tomography. This result is especially important for information-based interpretations of quantum mechanics, where quantum states, like probabilities, are taken to be states of knowledge rather than states of nature. We further demonstrate that the theorem fails for real Hilbert spaces and discuss the significance of this point.