bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spatial autocorrelation and red herrings in geographical ecology
Authors: Diniz‐Filho José Alexandre Felizola , Bini Luis Mauricio , Hawkins Bradford A. 
Published: March 2003

ABSTRACTAim Spatial autocorrelation in ecological data can inflate Type I errors in statistical analyses. There has also been a recent claim that spatial autocorrelation generates ‘red herrings’, such that virtually all past analyses are flawed. We consider the origins of this phenomenon, the implications of spatial autocorrelation for macro‐scale patterns of species diversity and set out a clarification of the statistical problems generated by its presence.Location To illustrate the issues involved, we analyse the species richness of the birds of western/central Europe, north Africa and the Middle East.Methods Spatial correlograms for richness and five environmental variables were generated using Moran's I coefficients. Multiple regression, using both ordinary least‐squares (OLS) and generalized least squares (GLS) assuming a spatial structure in the residuals, were used to identify the strongest predictors of richness. Autocorrelation analyses of the residuals obtained after stepwise OLS regression were undertaken, and the ranks of variables in the full OLS and GLS models were compared.Results Bird richness is characterized by a quadratic north–south gradient. Spatial correlograms usually had positive autocorrelation up to c. 1600 km. Including the environmental variables successively in the OLS model reduced spatial autocorrelation in the residuals to non‐detectable levels, indicating that the variables explained all spatial structure in the data. In principle, if residuals are not autocorrelated then OLS is a special case of GLS. However, our comparison between OLS and GLS models including all environmental variables revealed that GLS de‐emphasized predictors with strong autocorrelation and long‐distance clinal structures, giving more importance to variables acting at smaller geographical scales.Conclusion Although spatial autocorrelation should always be investigated, it does not necessarily generate bias. Rather, it can be a useful tool to investigate mechanisms operating on richness at different spatial scales. Claims that analyses that do not take into account spatial autocorrelation are flawed are without foundation.
Identifying and characterizing a five‐gene cluster of ATP‐binding cassette transporters mapping to human chromosome 17q24: a new subgroup within the ABCA subfamily
Authors: Arnould Isabelle , Schriml Lynn M. , Prades Catherine , Lachtermacher‐Triunfol Marcia , Schneider Thomas , Maintoux Christelle , Lemoine Cendrine , Debono Delphine , Devaud Catherine , Naudin Laurent , Bauché Stéphanie , Annat Mélanie , Annilo Tarmo , Allikmets Rando , Gold Bert , Denèfle Patrice , Rosier Marie , Dean Michael 
Published: March 2003

AbstractIntroductionThe ATP‐binding cassette (ABC) gene superfamily encodes a series of transporter proteins that move a wide variety of substances across extra‐ and intracellular membranes. Forty‐eight known human ABC genes can be divided into seven phylogenetically distinct subfamilies. The ABCA gene subfamily is found exclusively in multicellular eukaryotes.ResultsWe report here on a unique tandem array of five ABCA genes on chromosome 17q24 defining a phylogenetically distinct group. This is the largest cluster of mammalian ABC genes described to date. They are arranged head‐to‐tail and have similar intron/exon organization in both mouse and human. Northern analysis reveals a heterogeneous pattern of expression in human tissues, with ABCA5 and ABCA10 expressed in skeletal muscle, ABCA6 in the liver, ABCA9 in the heart, and ABCA8 in ovaries. This suggests that these proteins have distinct functions.
Changing Mortality of Cerebral Haemorrage
Authors: CHOUDARY ZAHID I. , CHAN MICHAEL T.Y. , BARSOUM S. , NORRIS J.W. 
Published: March 2003

The previous decline of the incidence of stroke is now less apparent. Most of this decline was in ischaemic stroke; the changes in haemorrhagic stroke are less certain.We have documented on our stroke data bank in Toronto the stroke frequency. We collected retrospective data of 182 admissions for cerebral haemorrhage. 126 (69%) were direct admissions to emergency and 56 (31%) were referral. In hospital mortaility rate was higher in the emergency group than in the referral group (52% vs 19.6%). Moreover, patients from the referral group were found to have predominant lobar haemorrhage and less proportion of central lesion. In 1976, 10.1% of strokes admitted rate in the week was 47%. In 1997, 10% of strokes were haemorrhagic but the mortality rate was 37% (P > 0.05).Although some of these differences probably represent referral bias, these data indicate a decline in mortality but not incidence.
Cost Effectiveness of t‐PA Therapy
Authors: NADAREISHVILI ZURAB G. , SMARAWSKA LILIANA T. , NORRIS JOHN W. 
Published: March 2003

Although the effect of t‐PA treatment in acute cerebral infarction remains controversial, there is evidence based data that it may prove effective if given early and with appropriate criteria.We have calculated the cost of t‐PA treatment in Canada assuming that 35 000 of the 50 000 yearly stroke incidence is due to acute ischemic stroke. The cost of treating one patient is about $7 000 CDN, and the cost effectiveness depends upon the number of eligible patients. At present in our region in Toronto, about 20% of these arrive in the emergency room of a tertiary care hospital within 3 hours.With regional stroke centres such as those in Canada, we calculate that with this degree of eligibility there would be considerable cost‐savings.
A randomized, double‐blind, placebo‐controlled study of the efficacy and safety of botulinum toxin type A in upper limb spasticity in patients with stroke
Authors: Bakheit A. M. O. , Pittock S. , Moore A. P. , Wurker M. , Otto S. , Erbguth F. , Coxon L. 
Published: March 2003

Objective. To study the efficacy and safety of botulinum toxin type A (BtxA) in the treatment of upper limb muscle spasticity, caused by stroke. Methods. This was a randomized, controlled trial. Patients received either placebo injections or a total of 1000 IU of BtxA (Dysport) into five muscles of the affected arm. Muscle tone was assessed using the Modified Ashworth Scale (MAS). Other outcome measures were the change in the joint range of motion (ROM), the Barthel index, pain score, goal attainment and the subjective evaluation of benefit by patients and investigators. The patients were assessed blind to randomization at baseline and 4, 8, 12 and 16 weeks after treatment. Results. Fifty nine patients were recruited and received treatment. One patient was lost to follow‐up before the last scheduled visit of the study. The group of patients who received BtxA had a significant reduction in the summed MAS score at week 4 compared with the placebo group (P=0.004). The magnitude of benefit over the 16 week follow‐up period was significantly reduced for the BtxA group in the wrist (P=0.004) and the finger joints (P=0.001) when compared with the placebo.There was no statistically significant difference between the groups in the joint ROM, muscle pain, goal‐attainment or the Barthel index scores at week 4 of the study. At week 16, the BtxA group showed significantly greater improvement in the passive ROM at the elbow (P=0.036). The patients’ global assessment of benefit at the end of the study showed that 16 (50%) patients in the placebo group had ‘much improved’ or had ‘some improvement’ compared with 24 (92.3%) patients in the BtxA group (P=0.007). The investigators’ rating for the same item was 16 (50%) and 23 (88.4%) patients, respectively (P=0.002).Sixteen and twenty patients in the BtxA and placebo groups, respectively, had an adverse event. The most frequently reported adverse events were accidental injury, respiratory and urinary tract infections and muscle pain. Conclusion. The findings of the present study suggest that treatment with BtxA in a dose of 1000 units reduces muscle tone in patients with post‐stroke upper limb spasticity. This effect is sustained for at least 16 weeks. BtxA is safe in the dose used in this study. Important note. The authors wish to emphasize that the botulinum toxin preparation used in this study was Dysport (Ipsen Ltd) which has a different therapeutic equivalence from other commercially available product, Botox (Allergan Inc.).
How do the Currently Used Prophylactic Agents Work in Migraine?
Authors: Goadsby PJ 
Published: March 2003

Since migraine attacks are often frequent they require management with agents that reduce their number. Such agents, although often effective, are mechanistically ill-understood, They have been suggested to work through four main mechanisms, 5HT2 antagonism, modulation of plasma protein extravasation, modulation of central aminergic control mechanisms and membrane stabilizing effects through actions at voltage-sensitive channels. The evidence for these mechanisms, except plasma protein extravasation (see Cutrer, this supplement) is examined in the light of current thoughts concerning the pathophysiology of migraine. The understanding of the action of preventative drugs is at a relatively immature stage. Recent developments in pharmacology and studies of the pathophysiology of migraine have provided a substrate around which concepts can be developed. The actions and indeed the locus of action of the preventatives is crucial since these drugs are likely to point to the basic defect which underlies the process responsible for a migraine attack. Understanding this process can only facilitate patient management both in terms of explaining the disease and its implications and in controlling its clinical manifestations.
Possible Mechanisms of Valproate in Migraine Prophylaxis
Authors: Cutrer FM , Limmroth V , Moskowitz MA 
Published: March 2003

Valproate has been shown to be an effective prophylactic treatment in migraine. Investigation of the mechanism of its antimigraine action is difficult due to the broad range of its biochemical effects and the complex nature of migraine pathophysiology. Valproate increases brain GABA levels and, in doing so, may suppress migraine-related events in the cortex, perivascular parasympathetics or trigeminal nucleus caudalis. There is experimental evidence that it suppresses neurogenic inflammation and directly attenuates nociceptive neurotransmission. In addition, valproate reportedly alters levels of excitatory and inhibitory neurotransmitters and exerts direct effects on neuronal membranes in vitro. Valproate's observed effect may ultimately result from a combination of actions at different loci. Our understanding of valproate's mechanism in migraine is made more difficult by the broad range of its biochemical effects and the complex nature of migraine pathophysiology. Valproate increases brain GABA levels and, in doing so, may suppress migraine-related events in the cortex, perivascular parasympathetics or trigeminal nucleus caudalis. It lowers aspartate levels and NMDA receptor activity which may suppress aura related cortical processes, or may modulate nociceptive transmission within TNC. The significance of valproate-induced changes in serotonin, dopamine, glycine, taurine and enkephalin levels is not known. There is experimental evidence that it suppresses neurogenic inflammation and directly attenuates nociceptive neurotransmission. Direct action on pain transmission is unlikely to be the only relevant action since the number as well as severity of attacks is decreased Valproate's observed effect may ultimately result from a combination of actions at different loci.
Incremental Absenteeism Due to Headaches in Migraine: Results from the Mig-Access French National Cohort
Authors: Michel P , Dartigues JF , Duru G , Moreau J , Salamon R , Henry P 
Published: March 2003

Objective To assess the costs of headache-related absenteeism of community-dwelling migraineurs, and to compare the amount of absenteeism between migraineurs aged 18 and older and age, sex, and occupation-matched nonheadache-prone subjects. Design Follow-up over a 3-month period. Samples 385 migraineurs and 313 nonheadache subjects representative of the setting. Methods Every day, the participants recorded the presence of headache, if any, and the work situation (unemployment, holiday, weekend, medical reason, nonmedical reason). Sickness-related absenteeism was the number of workdays missed or interrupted for medical reasons. Headache-related absenteeism was the sickness-related absenteeism during workdays with headaches. The annual headache-related absenteeism costs in France were extrapolated from these data in accordance with the mean income per occupational category. The incremental absenteeism and related costs were the difference between the two samples. Results Of working migraineurs, 20% had at least one period of absenteeism. During the 3 months, they missed or interrupted on average 1.4 days for medical reasons, 0.25 of which for headaches. Sickness-related absenteeism was statistically higher in migraineurs than in nonheadache-prone subjects. This difference was due to a higher absenteeism for comorbidity reasons, not for headache reasons, representing 20% of all sickness-related absenteeism. Migraineurs avoided sick leave for headache reasons. As an incremental total, 1.68 days or approximately 0.7% of the annual number of working days are lost on average per individual with migraine. The annual incremental headache-related absenteeism cost was 5.22 billions, i.e. 1,551 FF (US$240) per migraineur.
Treatment of Severe, Disabling Migraine Attacks in an Over-The-Counter Population of Migraine Sufferers: Results From Three Randomized, Placebo-Controlled Studies of the Combination of Acetaminophen, Aspirin, and Caffeine
Authors: Goldstein J , Hoffman HD , Armellino JJ , Battikha JP , Hamelsky SW , Couch J , Blumenthal H , Lipton RB 
Published: March 2003

Objective: To examine the benefits of acetaminophen, aspirin, and caffeine (AAC) in the treatment of severe, disabling migraine attacks, in a population of migraine sufferers for whom over-the-counter (OTC) medications are appropriate. Background: Subjects ( n = 1220) who met the International Headache Society criteria for migraine with or without aura were included in three independent clinical studies. Designl Methods: Post-hoc analysis of 172 subjects who met the criteria for severe, disabling migraine reported a history of migraine attacks characterized by at least severe pain and severe disability, and treated attacks with severe pain and at least severe disability. Subjects who usually vomited with 20% or more of their migraine attacks, and those with incapacitating disability (subjects who required bed rest for more than 50% of their attacks) were not eligible for enrollment. Results: From 1 h and continuing through 6 h postdose, the proportion of responders was significantly greater ( p≤0.01) for AAC than placebo. The pain intensity difference from baseline was significantly greater ( p≤0.05) for AAC than placebo from 0.5 h through 6 h. The proportion of subjects reporting improvement in functional disability, photophobia, and phonophobia was significantly greater for AAC than placebo from 2 h through 6 h postdose. Conclusions: The nonprescription combination of AAC was well tolerated and effective.
A Pharmacokinetic Interaction Study Between Butorphanol and Sumatriptan Nasal Sprays in Healthy Subjects: Importance of the Timing of Butorphanol Administration
Authors: Vachharajani NN , Shyu W-C , Nichola PS , Boulton DW 
Published: March 2003

Sumatriptan and butorphanol nasal sprays are commonly used agents for the management of migraine headaches. Under certain circumstances, these two agents may be administered closely in time. However, the possibility of a pharmacokinetic interaction and the safety of this regime have not been examined. In this crossover design study, 24 healthy subjects received the following four treatments, each separated by at least 7 days: 1 mg butorphanol (Stadol NS7®); 20 mg sumatriptan (Imitrex® Nasal Spray); or both formulations together with butorphanol administered either 1 or 30 min after sumatriptan. Serial plasma samples were collected for 24 h post-dose and analysed for butorphanol and/or sumatriptan by HPLC-MS/MS. Butorphanol plasma concentrations were reduced when it was administered 1 min (mean 28.6% decrease in AUC0-∞) , but not 30 min, after sumatriptan. The pharmacokinetics of sumatriptan were not substantially altered by butorphanol. The combination of nasally administered sumatriptan and butorphanol appeared safe. However, if butorphanol nasal spray is administered < 30 min after sumatriptan nasal spray, the analgesic effect of butorphanol may be diminished due to reduced nasal absorption resulting from probable transient vasoconstriction of nasal blood vessels by sumatriptan.
Women and the Mental Deficiency Act of 1913: citizenship, sexuality and regulation
Authors: Walmsley Jan 
Published: March 2003

SummaryThe present paper examines how women were targeted for sexual regulation and treated as ‘mental defectives’ under early‐twentieth‐century legislation, depriving them of citizenship. It also looks at factors which determined whether they continued to be detained in institutions or were ‘released’ into the community.
Future aspirations of students with severe learning disabilities and of their parents on leaving special schooling
Authors: Smyth Marisa , McConkey Roy 
Published: March 2003

SummaryThe majority of school‐leavers over 2 years from two special schools in Belfast were individually interviewed (n = 34) as were their parents (n = 37). The almost unanimous wish of the young people to have a job was not matched by the parents, although nearly half of the parents did express the wish that they would have at least part‐time work. The majority of young people and the parents envisaged living with the family albeit for different reasons. However, there was a strong emphasis on fostering the young person's independence and living with friends. Consequently, only a minority of families mentioned their son or daughter moving into traditional residential care settings. It is argued that it is not just the availability of services that need to increase in order to meet the aspirations of the young people and their parents; major changes are also needed in their form and function.
Application of boron isotopes to the understanding of fluid–rock interactions in a hydrothermally stimulated oil reservoir in the Alberta Basin, Canada
Authors: Williams L. B. , Wieser M. E. , Fennell J. , Hutcheon I. , Hervig R. L. 
Published: March 2003

AbstractBoron isotope ratios of reservoir minerals and fluids can be a useful geothermometer and monitor of fluid–rock interactions. In Cold Lake oil sands of northern Alberta, there is a large variation in δ11B of the produced waters generated during steam injection and recovery of oil and water. The higher temperature waters (∼ 200 °C) have isotopically light δ11B values (+ 3‰ to + 14‰) and high B contents (∼150 p.p.m.). It is inferred that the range of δ11B values of the hydrothermal fluids results from reaction with the reservoir rock, and is a function of the temperature of the fluid–rock interaction. The distinct B geochemistry of the produced waters can be used to show that there is no detectable mixing of the oil recovery waters with the regional formation waters or shallow groundwater aquifers containing potable water.Examination of B isotope ratios of reservoir minerals, before and after steam injection, allows the evaluation of sources of B in the reservoir. The only significant phase containing B is pumice. It shows generally positive δ11B values before steam injection and negative values after steam, with δ11B as low as − 28‰. Other possibly reactive phases include clay minerals and organic matter, but their abundance is not great enough to impact on the isotopic composition of the produced waters.This information makes it possible to evaluate the boron isotope fractionation equation derived from experimental data (Williams LB (2000) Boron isotope geochemistry during burial diagenesis. PhD Dissertation. The University of Calgary, Alberta, Canada; Williams LB, Hervig RL, Holloway JR, Hutcheon I (2001a) Boron isotope geochemistry during diagenesis: Part 1. Experimental determination of fractionation during illitization of smectite. Geochimica et Cosmochimica Acta, in press). The results show that the fractionation curve predicts the difference between δ11B of the pumice and hydrothermal fluids in the Cold Lake reservoir. This not only indicates that the reservoir fluids have approached boron isotope equilibrium with the reservoir rock, but also shows that B isotopes provide a useful geothermometer for hydrothermally stimulated oil reservoirs.
Quantifying secondary migration efficiencies
Authors: Sylta Ø. 
Published: March 2003

AbstractExploration success relies on properly risking the hydrocarbon system relevant for each prospect. Accurate risking of secondary migration efficiencies has been difficult due to lack of simple procedures that relate rock properties such as permeability and entry pressures to migration velocities, oil stringer heights and saturations. In order to achieve improved estimates of charge probabilities, equations for the secondary migration process are formulated based upon the Darcy flow and buoyancy conditions. An analytical solution of the formulated equations is shown, making it possible to construct charts for efficiently assessing the column height of secondary migration hydrocarbon stringers. The average oil (hydrocarbon) saturation of the migrating stringer can be computed, making it easy to compute the permeability related, secondary migration losses. Inputs to the chart are hydrocarbon flow‐rates and flow‐path width, hydrocarbon viscosity and density, carrier bed dip, permeability and entry pressures. Outputs are stringer heights, hydrocarbon saturation, relative permeability, migration velocities and migration losses. A procedure for including the new equations into existing basin scale fluid flow simulators is outlined and a Java applet for calculating the properties is described. The Java applet is useful for sensitivity studies, and can also be used to test results from basin simulators with the new migration efficiency equations. The analytical solution suggests that many published methods for calculating hydrocarbon migration in fluid flow simulators will over‐estimate hydrocarbon saturations and therefore losses. Calculated migration velocities will also be too low.