Showing papers by "Dalhousie University published in 1996"

The development and initial validation of the Systemic Lupus International Collaborating Clinics/American College of Rheumatology damage index for systemic lupus erythematosus.

Abstract: Objective. To develop and perform an initial validation of a damage index for systemic lupus erythematosus (SLE). Methods. A list of items considered to reflect damage in SLE was generated through a nominal group process. A consensus as to which items to be included in an index was reached, together with rules for ascertainment. Each center submitted 2 assessments, 5 years apart, on 2 patients with active and 2 with inactive disease, of whom 1 had increased damage and the other had stable disease. Analysis of variance was used to test the factors physician, time, amount of damage, and activity status. Results. Nineteen physicians completed the damage index on 42 case scenarios. The analysis revealed that the damage index could identify changes in damage seen in patients with both active and inactive disease. Patients who had active disease at both time points had a higher increase in damage. There was good agreement among the physicians on the assessment of damage in these patients. Conclusion. This damage index for SLE records damage occurring in patients with SLE regardless of its cause. The index was demonstrated to have content, face, criterion, and discriminant validity.

Gender variations in clinical pain experience.

Abstract: This review is a critical summary of research examining gender variations in clinical pain experience. Gender-comparative pain research was identified through Medline and Psychlit searches and references obtained from bibliographies of pertinent papers and books. Review of this research demonstrates that women are more likely than men to experience a variety of recurrent pains. In addition, many women have moderate or severe pains from menstruation, pregnancy and childbirth. In most studies, women report more severe levels of pain, more frequent pain and pain of longer duration than do men. Women may be at greater risk for pain-related disability than men but women also respond more aggressively to pain through health related activities. Women may be more vulnerable than men to unwarranted psychogenic attributions by health care providers for pain. Underlying biological mechanisms of pain and the contribution of psychological and social factors as they contribute to the meaning of pain for women and men warrant greater attention in pain research.

A full genome search in multiple sclerosis

Abstract: The aetiology of multiple sclerosis (MS) is uncertain. There is strong circumstantial evidence to indicate it is an autoimmune complex trait. Risks for first degree relatives are increased some 20 fold over the general population. Twin studies have shown monozygotic concordance rates of 25-30% compared to 4% for dizygotic twins and siblings. Studies of adoptees and half sibs show that familial risk is determined by genes, but environmental factors strongly influence observed geographic differences. Studies of candidate genes have been largely unrewarding. We report a genome search using 257 microsatellite markers with average spacing of 15.2 cM in 100 sibling pairs (Table 1, data set 1 - DS1). A locus of lambda>3 was excluded from 88% of the genome. Five loci with maximum lod scores (MLS) of >1 were identified on chromosomes 2, 3, 5, 11 and X. Two additional data sets containing 44 (Table 1, DS2) and 78 sib pairs (Table 1, DS3) respectively, were used to further evaluate the HLA region on 6p21 and a locus on chromosome 5 with an MLS of 4.24. Markers within 6p21 gave MLS of 0.65 (non-significant, NS). However, D6S461, just outside the HLA region, showed significant evidence for linkage disequilibrium by the transmission disequilibrium test (TDT), in all three data sets (for DS1 chi2 = 10.8, adjusted P < 0.01)(DS2 and DS3 chi2 = 10.9, P < 0.0005), suggesting a modest susceptibility locus in this region. On chromosome 5p results from all three data sets (222 sib pairs) yielded a multipoint MLS of 1.6. The results support genetic epidemiological evidence that several genes interact epistatically to determine heritable susceptibility.

Comparison of a Trial of Labor with an Elective Second Cesarean Section

Abstract: Background In an attempt to reduce the rate of cesarean section, obstetricians now offer a trial of labor to pregnant women who have had a previous cesarean section. Although a trial of labor is usually successful and is relatively safe, few studies have directly addressed the maternal and perinatal morbidity and mortality associated with this method of delivery. Methods We performed a population-based, longitudinal study of 6138 women in Nova Scotia who had previously undergone cesarean section and had delivered a singleton live infant in the period from 1986 through 1992. Results A total of 3249 women elected a trial of labor, and 2889 women chose to undergo a second cesarean section. There were no maternal deaths. The overall rate of maternal morbidity was 8.1 percent; 1.3 percent had major complications (a need for hysterectomy, uterine rupture, or operative injury) and 6.9 percent had minor complications (puerperal fever, a need for blood transfusion, or abdominal-wound infection). Although the overa...

Alcohol abuse in individuals exposed to trauma: A critical review.

Abstract: In this article, the author critically reviews studies on the relationship between exposure to trauma, posttraumatic stress disorder (PTSD), and alcohol abuse. After establishing that strong relationships exist between exposure to traumatic events and alcohol problems, and particularly between the diagnoses of PTSD and alcoholism, the author discusses various factors, theories, and possible mechanisms to account for these associations. Moreover, she discusses applications of these findings to the assessment and treatment of people exposed to trauma who abuse alcohol. Finally, the author outlines novel methods for testing theoretical hypotheses and makes suggestions for methodological improvements in future research. This article critically reviews the evidence for an important functional relationship between posttraumatic stress disorder (PTSD) and alcoholism. Although several reviewers have shown a significant overlap between certain anxiety disorders and alcohol abuse (e.g., B. J. Cox, Norton, Swinson, & Endler, 1990; Kushner, Sher, & Beitman, 1990; Pihl & Stewart, 1991 ), they did not consider the relationship between PTSD and alcoholism. One review examined the relationship between PTSD and substance abuse (i.e., Keane, Gerardi, Lyons, & Wolfe, 1988 ). However, their focus was very different from this review, assessing abuse of a wide range of chemical substances by only Vietnam veterans exposed to trauma. The purposes of this article are to (a) examine the empirical evidence for the cooccurrence of trauma exposure and alcohol problems and for the comorbidity between PTSD and alcoholism across various traumatic events; (b) critique methodological issues in the literature; (c) review theoretical mechanisms that may account for the relationship of trauma exposure, PTSD, and alcohol abuse; (d) discuss the implications of this research for the assessment and treatment of individuals comorbid for PTSD and alcoholism; and (e) suggest directions for future research. It should be made clear at the outset that this review focuses specifically on alcohol abuse in response to psychological trauma (e.g., sexual assault) as opposed to stressful life events (i.e., negative events that are not necessarily traumatic, such as divorce; Holmes & Rahe, 1967) or physical trauma (e.g., head injury). As these latter two issues are not a focus of this article, the interested reader is referred to reviews on the associations between alcohol abuse and stressful life events (Beckman, 1976; Benson & Wilsnack, 1983; Straussner, 1985 ) and alcohol abuse and physical trauma (Solomon & Malloy, 1992). Although conI thank Richard J. McNally and Robert O. Pihl for their helpful comments on drafts of this article.

An Accurate Parameterization of the Infrared Radiative Properties of Cirrus Clouds for Climate Models

Abstract: An accurate parameterization is presented for the infrared radiative properties of cirrus clouds. For the singlescattering calculations, a composite scheme is developed for randomly oriented hexagonal ice crystals by comparing results from Mie theory, anomalous diffraction theory (ADT), the geometric optics method (GOM), and the finite-difference time domain technique. This scheme employs a linear combination of single-scattering properties from the Mie theory, ADT, and GOM, which is accurate for a wide range of size parameters. Following the approach of Q. Fu, the extinction coefficient, absorption coefficient, and asymmetry factor are parameterized as functions of the cloud ice water content and generalized effective size ( Dge). The present parameterization of the single-scattering properties of cirrus clouds is validated by examining the bulk radiative properties for a wide range of atmospheric conditions. Compared with reference results, the typical relative error in emissivity due to the parameterization is ;2.2%. The accuracy of this parameterization guarantees its reliability in applications to climate models. The present parameterization complements the scheme for the solar radiative properties of cirrus clouds developed by Q. Fu for use in numerical models.

Podiform Chromitites in the Luobusa Ophiolite (Southern Tibet): Implications for Melt-Rock Interaction and Chromite Segregation in the Upper Mantle

Abstract: The Luobusa ophiolite in the Indus—ladling Zjingbo suture of southern Tibet hosts the largest known chromite deposit in China. The podiform chromitites occur in a well-preserved mantle sequence consisting of harzburgite with abundant lenses of dunite. The harzburgites have relatively uniform bulk-rock compositions with mg-numbers [100Mg/(Mg + Fe) ] ranging from 89 to 91 and show flat, unfractionated, chondrite-normaliied platinum group element (PGE) patterns. Their accessory chromite varies widely in cr-number [100Cr/(Cr + Al)] (1866). These rocks are essentially residua left after extraction of mid-ocean ridge basalt (MORB)-type magmas. The podiform chromitites display nodular, massive, disseminated and banded textures and typically have dunite envelopes that grade into the surrounding harzburgite and diopsidic harzburgite with increasing pyroxene contents. They consist of relatively uniform chromite with high cv-numbers (74-82), have strongly fractionated, chondrite-normalized PGE patterns with enrichment in Os, Ir and Ru relative to Rh, Pt and Pt, and are believed to have formed from a boninitic magma produced by a second stage of melting. Dunites contain accessory chromite intermediate in composition between those of harzburgite and chromitite and are believed to be the products of reaction between new boninitic magmas and old MORB-type peridotites. The melt-rock reaction removed pyroxene from the peridotites and precipitated olivine, forming dunite envelopes around the chromitite pods. The melts thus became more boninitic in composition and chromite saturated, leading to precipitation of chromite alone. The interplay of melt—rock interaction, chromite fractionation and magma mixing should lead to many fluctuations in melt composition, producing both massive and disseminated chromitites and phase layering within individual podiform bodies observed in the Luobusa ophiolite.

Error patterns on the Continuous Performance Test in non-medicated and medicated samples of children with and without ADHD : A meta-analytic review

Abstract: We systematically reviewed the patterns of Continuous Performance Test (CPT) errors of omission and commission exhibited by normal children and children with Attention Deficit and Hyperactivity Disorder (ADHD) under no drug, placebo and methylphenidate drug conditions. Findings from 26 studies were submitted to a meta-analytic procedure. In contrast to the contradictory findings of individual reports, our results revealed that children with ADHD made significantly more errors of omission and commission than normal children. As well, in children with ADHD and treated with methylphenidate, statistically significant reductions in the rate of both error types were noted. The effects of methylphenidate on the percentage of hits (i.e. 1 — omissions) were greater in experiments using shorter stimulus duration, smaller number of trials and higher probability of a target. Using Signal Detection Theory (SDT) parameters, we found that children with ADHD were less sensitive to the difference between targets and non-targets than their normal counterparts, while showing a comparable response bias. Similarly, the effects of methylphenidate were restricted to improving the sensitivity, while not affecting response bias, in both normal children and those with ADHD.

Photochemical release of biologically available nitrogen from aquatic dissolved organic matter

Abstract: DISSOLVED organic material in marine and freshwater ecosystems constitutes one of the Earth's largest actively cycled reservoirs for organic matter1. The bacterially mediated turnover of chemically identifiable, low-molecular-mass components of this pool has been studied in detail for nearly three decades, but these compounds constitute less than 20% of the total reservoir2. In contrast, little is known about the fate of the larger, biologically more refractory molecules—including humic substances—which make up the bulk of dissolved organic matter. Here we report results from bacterial bioassays and photochemical studies indicating that exposure to sunlight causes dissolved organic matter to release nitrogen-rich compounds that are biologically available, thus enhancing the bacterial degradation of humic substances. We demonstrate that ammonium is among the nitrogenous compounds released and is produced most efficiently by ultraviolet wavelengths. Photochemical release of ammonium from dissolved organic matter has important implications for nitrogen availability in many aquatic ecosystems, including nitrogen-limited high-latitude environments and coastal oceans, where inputs of terrestrial humic substances are high.

Cooperative hernia study. Pain in the postrepair patient

Abstract: Background The Cooperative Hernia Study assessed postoperative pain in a prospective trial as part of a larger study looking at the recurrence rate and other morbidity of the Bassini, McVay, and Shouldice repairs. Methods Patients were randomized to one of three surgical hernia repairs. Patients were seen in follow-up at 6, 12, and 24 months and were assessed for the presence of pain, numbness, paresthesia, and recurrence. Results Three hundred fifteen patients were seen in follow-up, with 276 seen at the 2-year mark. At 1 year, 62.9% of patients had groin or inguinal pain and 11.9% of patients had moderate to severe pain; 53.6% had pain and 10.6% of patients continued to report moderate to severe pain 2 years postoperatively. The predictors for long-term postoperative pain were as follows: absence of a visible bulge before the operation (p Conclusion Pain or numbness are common late sequelae of traditional external surgical hernia repairs. Strategies need to be developed to reduce the risk of these complications.

Plasma-exchange therapy in chronic inflammatory demyelinating polyneuropathy A double-blind, sham-controlled, cross-over study

Abstract: Eighteen patients with definite, untreated chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) of chronic progressive (nine patients) or relapsing course (nine patients) were randomized prospectively to receive 10 plasma-exchange (PE) or sham plasma-exchange (SPE) treatments over 4 weeks in a double-blind trial. After a wash-out period of 5 weeks or when they returned to baseline scores, patients were crossed over to the alternate treatments. Neurological function was assessed serially using a quantitative neurological disability score (NDS), a functional clinical grade (CG) and grip strength (GS) measurements. Electrophysiological studies were done at the beginning and end of each treatment. A primary 'intention to treat' analysis showed significant improvement with PE in all clinical outcome measures: NDS by 38 points, P < 0.001; CG by 1.6 points, P < 0.001; GS by +13 kg, P < 0.003 and in selected electrophysiological measurements, sigma proximal CMAP, P < 0.01; sigma motor conduction velocities, P < 0.006; sigma distal motor latencies, P < 0.01. Fifteen patients completed the trial and of those, 12 patients (80%) improved substantially with PE; i.e. five out of seven patients with chronic progressive course and seven out of eight patients with relapsing CIDP improved. There were three drop-outs; one patient lost venous access; one patient suffered a stroke and one patient left the trial to receive open treatment elsewhere. The improvement in motor functions correlated with the electrophysiological data, i.e. with improved motor conduction velocities and reversal of conduction block. Eight of 12 PE responders (66%) relapsed within 7-14 days after stopping PE. All improved with subsequent open label PE; all but two patients required long-term immunosuppressive drug therapy for stabilization. The PE non-responders improved with prednisone. We conclude that PE is a very effective adjuvant therapy for CIDP of both chronic progressive and relapsing course; concurrent immunosuppressive drug treatment is required. Exchange treatments should be given two to three times per week until improvement is established; the treatment frequency should then be tapered over several months.

Prevalence and source of pain in pediatric inpatients

Abstract: Our knowledge of the prevalence and sources of pain within hospital is limited. The present study is an epidemiological investigation of pain in a pediatric hospital. All children who were inpatients in a tertiary care hospital (excluding Neonatal ICU and psychiatry patients) and one parent per child were potential subjects. Interviews were conducted on three weekdays. Parent interviews were used for children less than 5 years of age (n = 102); child interviews were used for children age 5 years and older (n = 98). Subjects reported the intensity and source of the worst, usual and current pain during the past 24 h, and help received for pain. Medical and demographic variables and analgesics prescribed and administered were obtained from the medical record. Forty-nine percent of subjects reported clinically significant levels of worst pain. Twenty-one percent of subjects had clinically significant levels of usual pain. Causes of pain were variable and included disease, surgery, and intravenous lines (I.V.). Pain intensity was not significantly related to age, gender, patient type (medical, surgical), or diagnostic category. Children were given significantly less medication than was prescribed, regardless of their reported pain level. Nurses, mothers, and 'no-one' were frequently reported as helping with pain. Medications and nonpharmacological methods were reported as helpful in managing pain. Many children endure unacceptable levels of pain during hospitalization. Pain prevention and management must be more aggressive. Pain assessment should be approached with the same attention as vital signs. Improvements in analgesic prescription and administration practices and non-pharmacological pain control methods are needed.

Alpha-tubulin from early-diverging eukaryotic lineages and the evolution of the tubulin family.

Abstract: The tubulin gene family, which includes alpha-,beta-, and gamma-tubulin subfamilies, is composed of highly conserved proteins which are the principle structural and functional components of eukaryotic microtubules. We are interested in (1) establishing when in eukaryotic evolution the duplications leading to paralogous alpha, beta, and gamma subfamilies occurred and (2) the possible utility of tubulin sequences in reconstructing organismal phylogeny. To broaden the taxonomic representation of alpha-tubulins so that it roughly equals that of beta-tubulins, alpha-tubulin genes from three Microsporidia (Encephalitozoon hellem, Nosema locustae, and Spraguea lophii), two Parabasalia (Monocercomonas sp. and Trichomitus batrachorum), and one Heterolobosean (Acrasis rosea) were sequenced. With these new genes, phylogenetic trees of alpha- and beta-tubulins were constructed and compared. Trees were congruent with each other, but incongruent with other molecular phylogenies. The agreement between alpha- and beta-tubulin trees could arise by the co-adaptation of one molecule to variants of the other as a result of their intimate steric association in microtubules. Thus, these trees may not be providing independent support for the phylogenetic results. However, one of these unexpected results, that microsporidia cluster with fungi, is supported by other circumstantial evidence, and may therefore reflect a real relationship despite the basal position usually assigned to microsporidia. Relationships between the three tubulins were also examined by constructing trees of all three types. These trees were found to be of limited value for determining the position of the root within each subfamily because of the great interfamily distances, but they do confirm the classification of all known genes into three monophyletic subfamilies. Divergent genes from Caenorhabditis elegans and Saccharomyces cerevisiae that have been proposed to represent the novel classes delta- and epsilon-tubulin were found to be specifically related to gamma-tubulins from animals and fungi respectively, and therefore are best seen as rapidly evolving orthologues of gamma-tubulin.

Incidence of Epilepsy in Childhood and Adolescence: A Population‐Based Study in Nova Scotia from 1977 to 1985

Abstract: Data from a regional EEG laboratory allowed us to identify almost all children in Nova Scotia (population 85,000) with one or more unprovoked, afebrile seizures from 1977 through 1985. We then reviewed hospital and pediatric neurology physician charts to limit cases to those with two or more definite afebrile seizures between the ages of 1 month and 16 years. In all, 693 children developed epilepsy: typical childhood absence seizures (AS) (97), either generalized tonic-clonic (GTCs) or partial seizures either secondarily generalized or not (511), and other generalized seizure types, including infantile spasms (IS) as well as myoclonic, akinetic, tonic, and atypical AS (85). The incidence of epilepsy was 118 in 100,000 for children aged less than 1 year, 48 in 100,000 for those aged 1-5 years, 43 in 100,000 for those aged 6-10 years, and 21 in 100,000 for those aged 11-15 years. The incidence for each year of age between 1 and 10 years was remarkably constant (mean 46 in 100,000 +/- 7 SD). Comparison of the incidence rates showed significant differences for those aged less than one year as compared with all others, and for those aged greater than 10 years as compared with those aged 1-10 years. We conclude that the incidence of epilepsy is highest in the first year of life, plateaus in early childhood, and decreases markedly after age 10 years. The overall incidence of epilepsy in childhood is lower than that reported in previous studies.

Parents' management of children's pain following ‘minor’ surgery

Abstract: The aim of the investigation was to evaluate the prevalence, severity, and parents' management of children's pain following short-stay and day surgery. The subjects were 189 parents of children (2-12 years of age) who had undergone short-stay or day surgery. Parents completed a 3-day diary of their child's pain and the methods used to alleviate it. There were clear differences in pain reported according to type of surgery. Some surgery, such as insertion of myringotomy tubes, appeared to cause little pain. Other procedures, including tonsillectomy, circumcision, and strabismus repair, resulted in about one-half the children experiencing clinically significant pain (> or = 30 mm on a 100 mm VAS). Sixty-eight percent of the parents reported they had been instructed to use acetaminophen for pain 'if necessary', 13% had been told to use acetaminophen regularly, and 8% recalled no instructions. Of the parents who rated their child's pain as significant, 13% administered no pain medication and 47% gave 1-3 doses on day 2. On day 3, 17% gave no medication and 45% gave 1-3 doses. Some types of 'minor' surgery result in significant pain postoperatively. Even when parents recognise that their children are in pain, most give inadequate doses of medication to control the pain.

Survival of cholinergic forebrain neurons in developing p75NGFR-deficient mice.

Abstract: The functions of the low-affinity p75 nerve growth factor receptor (p75 NGFR ) in the central nervous system were explored in vivo. In normal mice, approximately 25 percent of the cholinergic basal forebrain neurons did not express TrkA and died between postnatal day 6 and 15. This loss did not occur in p75 NGFR -deficient mice or in normal mice systemically injected with a p75 NGFR -inhibiting peptide. Control, but not p75 NGFR -deficient, mice also had fewer cholinergic striatal interneurons. Apparently, p75 NGFR mediates apoptosis of these developing neurons in the absence of TrkA, and modulation of p75 NGFR can promote neuronal survival. Cholinergic basal forebrain neurons are involved in learning and memory.

Maternal Cigarette Smoking as a Risk Factor for Placental Abruption, Placenta Previa, and Uterine Bleeding in Pregnancy

Abstract: The authors carried out an epidemiologic study to evaluate the role of maternal cigarette smoking as a potential risk factor for placental abruption, placenta previa, and uterine bleeding of unknown etiology in pregnancy. Data for this prospective cohort study were obtained from women seeking prenatal care at any of the two tertiary, seven regional, or 17 community hospitals in the province of Nova Scotia, Canada, between January 1, 1986, and December 31, 1993. A total of 87,184 pregnancies (among 61,667 women) were registered in the database. Women who smoked during pregnancy (33%) were compared with nonsmokers, and all women were followed until the termination of pregnancy. Placental abruption was indicated in 9.9 per 1,000 pregnancies, while placenta previa and uterine bleeding of unknown etiology were indicated in 3.6 and 58.9 per 1,000 pregnancies, respectively. Women who smoked had a twofold increase in the risk of abruption (relative risk = 2.05, 95% confidence interval (CI) 1.75-2.40) in comparison with nonsmokers, while the relative risk for placenta previa was 1.36 (95% CI 1.04-1.79). However, cigarette smoking was not found to be associated with uterine bleeding of unknown etiology (relative risk = 1.01, 95% CI 0.94-1.08). There was no evidence for an increased risk of uteroplacental bleeding disorders with increasing numbers of cigarettes smoked. All analyses were adjusted for potentially confounding factors through logistic regression models based on the method of generalized estimating equations. The study confirms a positive association between cigarette smoking and placental abruption and a weak association with placenta previa but not with other uterine bleeding. The distinct pattern of results for placental abruption, placenta previa, and uterine bleeding of unknown origin suggests that these three uteroplacental bleeding disorders do not have a common etiology in relation to cigarette smoking.

Babysitting, dive synchrony, and indications of alloparental care in sperm whales

Abstract: Young sperm whales (Physeter macrocephalus) serially accompany different members of their social group at the surface while the majority of the group is foraging at depth. The presence of a nearby larger whale is likely to increase the survival prospects of the young animal. In studies off the Galapagos Islands, first-year calves were less likely to be seen at the surface alone than were larger whales, and groups containing calves showed less synchronous diving behaviour – shorter intervals with no larger whales at the surface – than those without calves. This difference in diving synchrony was not solely the result of behaviour by individuals assumed to be the mothers of calves (as they spent a disproportionate amount of time accompanying them). Thus babysitting in sperm whales seems to be a form of alloparental care. Its benefit may have been an important factor in the evolution of sociality in female sperm whales.

Factors Associated with Institutionalization of Older People in Canada: Testing a Multifactorial Definition of Frailty

Abstract: OBJECTIVES: To test a model of frailty by examining factors associated with institutionalization of older people in Canada; to assess whether diagnostic data provided information about risk beyond that provided by data on functional capacity and demographic variables. METHODS: Cross-sectional study of 1258 institutional subjects and 9113 community-dwelling older adults from the Canadian Study of Health and Aging. RESULTS: Multiple logistic regression analysis showed that female gender, being unmarried, absence of a caregiver, presence of cognitive impairment (including all types of dementia), functional impairment, diabetes mellitus, stroke, and Parkinson's disease were independently associated with being in a long-term care facility. CONCLUSION: Frailty appears to be a multidimensional construct, and not simply a synonym for dependence in Activities of Daily Living. Studies of health outcomes in older people should include diagnostic data as well as demographic information and data on functional capacity.

Development and preliminary validation of a postoperative pain measure for parents.

Abstract: Parents are now primarily responsible for the at home assessment and treatment of their children's pain following minor surgery. Although some research has suggested that parents underestimate their children's pain following surgery, no behavioral measure exists to assist parents in pain assessment. The Postoperative Pain Measure for Parents was developed based on cues parents reported using to assess their children's pain (e.g. changes in appetite, activity level). The purpose of the present study was to develop and validate this measure by examining the relation between parent-report of child behaviors and child-rated pain. Subjects were 110 children (56.4% male) aged 7-12 years undergoing day surgery at a tertiary-care children's hospital and their parents. Parents and children completed a pain diary for the 2 days following surgery. Children rated their pain and emotional distress and parents rated the presence or absence of specific behaviors from a checklist. Correlations were conducted between each of the 29 behavioral items and child-rated pain on Day 1; 14 items with correlations less than 0.30 were dropped. The remaining 15 items were subjected to a principal axis factor analysis. A one-factor solution was the best fit for the data. The items were then summed to yield a total score out of 15. Internal consistency reliabilities for the measure and correlations with child-rated pain were high on both days following surgery. Child-rated pain and emotional distress were moderately correlated. The Postoperative Pain Measure for Parents was also positively correlated with child-rated emotional distress on both days following surgery. As child-rated pain decreased from Day 1 to Day 2, so did scores on the behavioral measure. The Postoperative Pain Measure for Parents was successful in discriminating between children who had undergone no/low pain surgeries and children who had undergone moderate to high pain surgeries. There were no significant differences in scores on the behavioral measure for child age or sex. Using a cut-off score of six out of 15, the measure showed excellent sensitivity (> 80%) and specificity (> 80%) in selecting children who reported clinically significant levels of pain. This study provides preliminary evidence for the use of the Postoperative Pain Measure for Parents as a valid assessment tool with children between the ages of 7-12 years following day surgery. It is internally consistent and strongly related to child-rated pain. Future research should explore the use of this measure with a younger sample and children with developmental delays.

Mechanical model for subduction-collision tectonics of Alpine-type compressional orogens

Abstract: Alpine-type orogens are characterized by three distinct convergent tectonic phases: subduction with deformation that has primarily single vergence, a transition from subduction to collision, and continental collision with double vergence. Although the Cenozoic history of the European Alps has additional complexities, a mechanical explanation for these three phases would provide the necessary crustal-scale framework in which to develop an understanding of the smaller-scale processes. We present results from a simple numerical model, which explain the mechanics of these three phases as a consequence of the changing buoyancy of the lithosphere subducted beneath the orogen. The development and exhumation of a subduction complex, suture zone, and basement nappe stack (Piemont suture, Penninic Nappes); the presence of a crustal-scale back fold and thrust (Insubric Line); and uplift of basement on the pro- (European) side of the orogen (external basement massifs) may be explained as a simple consequence of changing dynamics during the transition from subduction to collision.