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While the ecological significance of hyporheic exchange and fine particle transport in rivers is well established, these processes are generally considered irrelevant to riverbed morphodynamics. We show that coupling between hyporheic exchange, suspended sediment deposition, and sand bedform motion strongly modulates morphodynamics and sorts bed sediments. Hyporheic exchange focuses fine-particle deposition within and below mobile bedforms, which suppresses bed mobility. However, deposited fines are also remobilized by bedform motion, providing a mechanism for segregating coarse and fine particles in the bed. Surprisingly, two distinct end states emerge from the competing interplay of bed stabilization and remobilization: a locked state in which fine particle deposition completely stabilizes the bed, and a dynamic equilibrium in which frequent remobilization sorts the bed and restores mobility. These findings demonstrate the significance of hyporheic exchange to riverbed morphodynamics and clarify how dynamic interactions between coarse and fine particles produce sedimentary patterns commonly found in rivers., (© 2021. The Author(s).)

Ice sintering is a form of metamorphism that drives the microstructural evolution of an aggregate of grains through surface and volume diffusion. This leads to an increase in the grain-to-grain contact area ("neck") and density of the aggregate over time, resulting in the evolution of its strength, porosity, thermal conductivity, and other properties. This process plays an important role in the evolution of icy planetary surfaces, though its rate and nature are not well constrained. In this study, we explore the model of Swinkels and Ashby (1981), and assess the extent to which it can be used to quantify sintering timescales for water ice. We compare predicted neck growth rates to new and historical observations of ice sintering, and find agreement to some studies at the order of magnitude level. First-order estimates of neck growth timescales on planetary surfaces show that ice may undergo significant modification over geologic timescales, even in the outer solar system. Densification occurs over much longer timescales, suggesting some surfaces may develop cohesive, but porous, crusts. Sintering rates are extremely sensitive to temperature and grain size, occurring faster in warmer aggregates of smaller grains. This suggests that the microstructural evolution of ices may vary not only throughout the solar system, but also spatially across the surface and in the near-surface of a given body. Our experimental observations of complex grain growth and mass redistribution in ice aggregates point to components of the model that may benefit from improvement, and areas where additional laboratory studies are needed.

A theoretical debate about whether parasitoids should be time or egg limited now recognizes both as feasible, and interest has turned to determining the circumstances under which each might arise in the field, and their implications for parasitoid behaviour and evolution. Egg loads of parasitoids sampled from the field are predicted to show a negative response to host availability, but empirical support for this relationship is scarce. We measured how a parasitoid's egg load responded to seasonal fluctuations in host population density and recorded the predicted correlation. In early summer, parasitoids were at high risk of time limitation due to low host availability, and in late summer, their offspring were at greater risk of egg limitation due to high host availability. Despite clear seasonal changes in selection pressures on egg load and lifespan, the parasitoid showed no evidence of seasonal variation in its reproductive strategy. We made minor modifications to a previously published model to explore the effects of seasonal variation in host availability on optimal investments in eggs and lifespan and obtained several new results. In particular, under circumstances analogous to some of those observed in our field study, temporal stochasticity in reproductive opportunities can cause investments in eggs to increase, rather than decrease as previously predicted. Our model results helped to explain the parasitoid's lack of a seasonally varying reproductive strategy. Understanding the evolution of parasitoid egg load would benefit from a shift of research emphasis from purely stochastic variation in parasitoid reproductive opportunities to greater consideration of host dynamics., (© 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.)

Although an uncommon entity, familial glomangiomatosis is often a source of significant discomfort to affected patients and impacts quality of life. Patients develop numerous painful vascular lesions, beginning in childhood. Because management strategies for this entity are sparsely reported in the literature, additional study is needed to establish best practice. We report positive results with the use of Nd:YAG laser in treating symptomatic lesions of familial glomuvenous malformation.

Live organisms intercepted from treated commodities during phytosanitary inspections usually arouse suspicions of treatment failure, sub-standard treatment application, or post-treatment infestation. The additional possibility that some treatments could kill slowly, meaning commodities might be inspected before pests have succumbed, is seldom considered for treatments other than irradiation. We used a novel biochemical viability assay to measure delays between methyl bromide fumigation and mortality of dipteran eggs, and evaluated the correspondence between egg viability and egg morphological features. Our experimental conditions simulated shipping of rock melons from Australia to New Zealand by sea and air. No eggs survived fumigation, but they took 3-20 days to die, whereas phytosanitary inspections of rock melons occur within 2-7 days. Delays were not influenced by methyl bromide concentration, but were significantly lengthened by cooler storage temperatures. Methyl bromide's preservative effects delayed degradation of egg morphology, so the biochemical assay detected mortality long before morphological signs of egg death appeared. The results show that commodities subjected to effective methyl bromide treatments are at risk of being inspected before all pests have either died, or started to exhibit morphological signs of death. This could cause commodities to be unnecessarily rejected by quarantine authorities. Better methods than inspection for live pests are needed to assist authorities to gain assurance that treated commodities have been effectively disinfested. These could be developed by exploiting biochemical responses of pests and commodities to treatments.

Death is inevitable, but dying well is not. Despite the role of medical professionals as overseers of dying in contemporary society, there is comparatively little discourse among doctors about the constituents of a good death. In the 15th century, by contrast, the Ars moriendi portrayed normative medieval ideas about good and bad deaths. At a time when dying could be viewed as a performed battle against damnation, the Ars moriendi codified a set of moral precepts that governed the expression of autonomy, relations between the dying and the living and orientation towards God. In these images, dying well is a moral activity that results from active decisions by the dying person to turn from earthly preoccupations to contemplation of, and submission to, the divine. It is likely in contemporary society that there is a range of understandings of the "good death". While attitudes to personal autonomy may differ, reflectiveness and dying at home in the presence of family (expressed in the Ars moriendi), remain part of many modern notions of the good death. We argue that medical institutions continue to construct death as a performed battle against physical debility, even when patients may have different views of their preferred deaths. The dialectic approach of the Ars moriendi may offer a way for contemporary doctors to reflect critically on the potential dissonance between their own approach to death and the variety of culturally valorised "good deaths".

Objective: Supplementary questionnaires provide additional information from subgroups, but may have an attritional effect on response rates. We examined the effects of different instruction methods on response rates to a two-part questionnaire., Methods: The ACT Kindergarten Health Survey comprises a health questionnaire for all school-entry children. A supplementary questionnaire targets children with respiratory symptoms. We cluster-randomised 109 schools in the ACT (4,494 children) to two instruction groups. Group 1 (instruction burden) had instructions to complete the supplementary questionnaire if certain questions in the primary questionnaire were answered. Group 2 (response burden) had instructions to complete both questionnaires irrespective of answers to the primary questionnaire., Results: Instructing all respondents to complete both questionnaires regardless of eligibility resulted in a statistically significantly lower primary questionnaire response rate (82% vs. 87%), but a statistically significantly higher response rate to the supplementary questionnaire (99% vs. 91%). The net effect was a small overall gain (82% vs. 79%) for the response burden group., Conclusion: Increasing the response burden had a minor impact on response rate to the primary questionnaire, but increased the response rate for most items to the supplementary questionnaire., Implications: Large surveys may be broken into primary and supplementary questionnaires, if strategies to maximise response rates are used. Questionnaires may need to be modified to take into account the likely attrition on response to either questionnaire resulting from instruction and response burdens.

Eight South American geographical populations of the parasitoid Microctonus hyperodae Loan were collected in South America (Argentina, Brazil, Chile and Uruguay) and released in New Zealand for biological control of the weevil Listronotus bonariensis (Kuschel), a pest of pasture grasses and cereals. DNA sequencing (16S, COI, 28S, ITS1, beta-tubulin), RAPD, AFLP, microsatellite, SSCP and RFLP analyses were used to seek markers for discriminating between the South American populations. All of the South American populations were more homogeneous than expected. However, variation in microsatellites and 16S gene sequences corroborated morphological, allozyme and other phenotypic evidence of trans-Andes variation between the populations. The Chilean populations were the most genetically variable, while the variation present on the eastern side of the Andes mountains was a subset of that observed in Chile.

Objective: To determine whether psychosocial factors, chronic diseases, and common geriatric problems are associated with poor physical function 3 years after primary total hip replacement (THR)., Methods: We studied a sample of Medicare recipients in Ohio, Pennsylvania, and Colorado (n = 922) who underwent primary THR in 1995 (mean +/- SD age 73.1 +/- 5.6 years, 32% men). Participants completed a questionnaire regarding lifestyle factors, medical history, and quality of life approximately 3 years after the surgery. Physical function was measured using the function subscale of the Western Ontario and McMaster Universities Osteoarthritis Index. We assessed the relationship between functional outcome 3 years postsurgery and 4 predictor domains: pain or complications in the operated hip, other musculoskeletal comorbidity, medical factors (obesity, chronic medical comorbidity, rheumatoid arthritis, and such common geriatric problems as falls, poor balance, or incontinence), and psychosocial factors (mental health, regular alcohol consumption, smoking, provider role, living alone, and education)., Results: Ten percent of subjects had poor functional status. In a logistic regression model controlling for sex and age, the following factors were associated with an increased risk for poor functional status (in order of importance): pain in the back or lower extremity, severe pain in the operated hip, poor mental health, more than 1 common geriatric problem, obesity, and less than college education., Conclusion: Pain in the operated hip was strongly associated with poor functional status 3 years after THR. However, other factors associated with poor functional status were not related to the hip. Our results suggest that a comprehensive assessment of functional status in elderly THR patients should include assessment of common geriatric problems, mental health status, and weight.

Field enclosure and laboratory cage experiments designed to measure the impact of the parasitoid Microctonus hyperodae Loan on the Argentine stem weevil, Listronotus bonariensis (Kuschel) have shown that under high parasitoid pressure, there is significant weevil mortality without obvious parasitism. Parasitoid-exposed, but unparasitized portions of caged populations died at rates significantly higher than both the parasitized weevils from the same population and the unexposed controls. Unexpectedly, parasitized weevils had the lowest mortality rates (prior to larval parasitoid emergence). It was of ecological significance that this mortality effect was detected under field conditions using several years of empirically-collected population dynamics data. Under both field and laboratory conditions this mortality was found to occur within shorter time intervals than that required for full parasitoid larval development; thus it could not be attributed to the mortality that occurs after the emergence of prepupal parasitoids. The mechanism for this mortality remains undetermined, although it could possibly be linked to pseudoparasitism.

The thelytokous parasitoid, Microctonus hyperodae Loan, was collected from eight South American locations and introduced to New Zealand in 1991 for biological control of Argentine stem weevil, Listronotus bonariensis (Kuschel) (Coleoptera: Curculionidae). Parasitoids from each population were released in equal numbers at each New Zealand site to give them the same opportunities to establish. Population markers have been sought to identify the South American geographic populations that have become most successful in New Zealand. These would assist in determining the importance of concepts such as climate matching and host-parasitoid coevolution to the establishment of natural enemies in new regions for biological control. Vertical polyacrylamide electrophoresis was used to survey 16 enzymes and ten calcium binding proteins, and this paper reports variation at three putative loci. Malate dehydrogenase, a dihydrolipoamide dehydrogenase isozyme and a calcium binding protein exhibited clear genetic variation, each with two alleles. All M. hyperodae isofemale lines from east of the Andes mountains shared one genotype, all but one from west of the Andes shared another, while a population from within the Andes contained both genotypes. This variation was highly congruent with previously described morphometric variation. At two loci, the maintenance of heterozygotes, and the absence of homozygotes, within isofemale lines suggested M. hyperodae thelytoky is apomictic.

Background: The mortality and complication rates of many surgical procedures are inversely related to hospital procedure volume. The objective of this study was to determine whether the volumes of primary and revision total hip replacements performed at hospitals and by surgeons are associated with rates of mortality and complications., Methods: We analyzed claims data of Medicare recipients who underwent elective primary total hip replacement (58,521 procedures) or revision total hip replacement (12,956 procedures) between July 1995 and June 1996. We assessed the relationship between surgeon and hospital procedure volume and mortality, dislocation, deep infection, and pulmonary embolus in the first ninety days postoperatively. Analyses were adjusted for age, gender, arthritis diagnosis, comorbid conditions, and income. Analyses of hospital volume were adjusted for surgeon volume, and analyses of surgeon volume were adjusted for hospital volume., Results: Twelve percent of all primary total hip replacements and 49% of all revisions were performed in centers in which ten or fewer of these procedures were carried out in the Medicare population annually. In addition, 52% of the primary total hip replacements and 77% of the revisions were performed by surgeons who carried out ten or fewer of these procedures annually. Patients treated with primary total hip replacement in hospitals in which more than 100 of the procedures were performed per year had a lower risk of death than those treated with primary replacement in hospitals in which ten or fewer procedures were performed per year (mortality rate, 0.7% compared with 1.3%; adjusted odds ratio, 0.58; 95% confidence interval, 0.38, 0.89). Patients treated with primary total hip replacement by surgeons who performed more than fifty of those procedures in Medicare beneficiaries per year had a lower risk of dislocation than those who were treated by surgeons who performed five or fewer of the procedures per year (dislocation rate, 1.5% compared with 4.2%; adjusted odds ratio, 0.49; 95% confidence interval, 0.34, 0.69). Patients who had revision total hip replacement done by surgeons who performed more than ten such procedures per year had a lower rate of mortality than patients who were treated by surgeons who performed three or fewer of the procedures per year (mortality rate, 1.5% compared with 3.1%; adjusted odds ratio, 0.65; 95% confidence interval, 0.44, 0.96)., Conclusions: Patients treated at hospitals and by surgeons with higher annual caseloads of primary and revision total hip replacement had lower rates of mortality and of selected complications. These analyses of Medicare claims are limited by a lack of key clinical information such as operative details and preoperative functional status.

Background: To determine the age-specific prevalence of Lyme disease and whether preventive behaviors on Nantucket Island correlate with Lyme disease, we surveyed island residents., Methods: A survey with questions on Lyme disease symptoms, history, and preventive behaviors was mailed to all residents. Respondents were stratified by likelihood of having had Lyme disease. A subsample was selected for examination, and then classified according to the Lyme disease national surveillance case definition., Results: The overall lifetime prevalence of Lyme disease for Nantucket residents was 15% (CI, 10%-19.8%): 19% among females, and 11% among males. The prevalence was highest among age groups 0-16 and 30-49 years. Overall, 86% of the population practiced at least one behavior. The most frequently reported preventive behavior was checking oneself for ticks (80%), followed by wearing protective clothing (53%), avoiding tick areas (34%), and using tick repellent (11%). Younger individuals practiced fewer preventive behaviors than older individuals (p=0.001). Although males reported greater tick exposure than females, females uniformly practiced preventive behaviors more frequently (p=0.001). The practice of preventive behaviors was not associated with a history of Lyme disease, but finding more than 5 ticks per year on oneself was (p=0.001)., Conclusion: Lyme disease is highly prevalent on Nantucket Island. Young people are particularly at risk and health education should emphasize preventive behaviors less frequently practiced: using tick repellent, avoiding tick areas, and wearing protective clothing.

Background: Vaccination against Lyme disease appears to be safe and effective; however, the cost per quality-adjusted life-year (QALY) gained with vaccination is unknown., Methods: We developed a decision-analytic model to evaluate the cost-effectiveness of vaccination compared with no vaccination in individuals living in endemic areas of Lyme disease. Our analysis encompassed a 10-year time horizon including a 2-year vaccination schedule with an additional year of vaccine effectiveness. The costs and probabilities of vaccination risk, compliance and efficacy, and Lyme disease clinical sequelae and treatment were estimated from the literature. Health-related quality-of-life weights of the various clinical sequelae of Lyme disease infection were obtained from a sample of 105 residents from Nantucket Island, Massachusetts., Results: Vaccinating 10 000 residents living in endemic areas with a probability of Lyme disease per season of 0.01 averted 202 cases of Lyme disease during a 10-year period. The additional cost per QALY gained compared with no vaccination was $62 300. Vaccination cost $12 600/QALY gained for endemic areas with an attack rate of 2.5% per season, and $145 200/QALY gained for an attack rate of 0.5%. Vaccinating individuals over an accelerated 2-month vaccination schedule improved the cost-effectiveness to $53 700/QALY gained. If a yearly booster shot is required for persisting efficacy, the marginal cost-effectiveness ratio increases to $72 700/QALY. The cost-effectiveness of vaccination was most sensitive to the Lyme disease treatment efficacy and assumptions about the persistence of vaccination effect., Conclusion: Vaccination against Lyme disease appears only to be economically attractive for individuals who have a seasonal probability of Borrelia burgdorferi infection of greater than 1%.

Previous studies suggest that concurrent Lyme disease and babesiosis produce a more sever illness than either disease alone. The majority of babesiosis infections, however, are subclinical. Our objective was to characterize on the basis of a total-population survey of Nantucket Island, Massachusetts, whether coexposure to Lyme disease and babesiosis causes more severe illness or poorer long-term outcomes than Lyme disease alone. In this retrospective cohort study, residents indicating a history of Lyme disease were compared with randomly selected population controls on a standardized medical history, blinded physical examination, and serological studies for Borrelia burgdorferi and Babesia microti. Serological evidence of exposure to babesiosis was not associated with increased severity of acute Lyme disease. The groups did not differ with regard to the prevalence of constitutional, musculoskeletal, or neurological symptoms a mean of 6 years after acute Lyme disease. Prior Lyme disease and serological exposure to B. microti are not associated with poorer long-term outcomes or more persistent symptoms Lyme disease alone.

During late 1999/early 2000, the solid state imaging experiment on the Galileo spacecraft returned more than 100 high-resolution (5 to 500 meters per pixel) images of volcanically active Io. We observed an active lava lake, an active curtain of lava, active lava flows, calderas, mountains, plateaus, and plains. Several of the sulfur dioxide-rich plumes are erupting from distal flows, rather than from the source of silicate lava (caldera or fissure, often with red pyroclastic deposits). Most of the active flows in equatorial regions are being emplaced slowly beneath insulated crust, but rapidly emplaced channelized flows are also found at all latitudes. There is no evidence for high-viscosity lava, but some bright flows may consist of sulfur rather than mafic silicates. The mountains, plateaus, and calderas are strongly influenced by tectonics and gravitational collapse. Sapping channels and scarps suggest that many portions of the upper approximately 1 kilometer are rich in volatiles.

To develop a standardized, practical, self-administered questionnaire to monitor pediatric patients with burns and to evaluate the effectiveness of comprehensive pediatric burn management treatments, a group of experts generated a set of items to measure relevant burn outcomes. Children between the ages of 5 and 18 years were assessed in a cross-sectional study. Both parent and adolescent responses were obtained from children 11 to 18 years old. The internal reliability of final scales ranged from 0.82 to 0.93 among parents and from 0.75 to 0.92 among adolescents. Mean differences between parent and adolescent were small; the greatest difference occurred in the appearance subscale. Parental scales showed evidence of validity and potential for sensitivity to change. In an effort to support the construct validity of the new scales, they were compared with the Child Health Questionnaire and related to each other in clinically sensible ways. These burn outcomes scales reliably and validly assess function in patients with burns, and the scales have been developed in such a way that they are likely to be sensitive to change over time.

Background: Previous follow-up studies of patients with Lyme disease suggest that disseminated infection may be associated with long-term neurologic and musculoskeletal morbidity., Objective: To determine clinical and functional outcomes in persons who were treated for Lyme disease in the late 1980s., Design: Population-based, retrospective cohort study., Setting: Nantucket Island, Massachusetts., Participants: 186 persons who had a history of Lyme disease (case-patients) and 167 persons who did not (controls)., Measurements: Standardized medical history, physical examination, functional status measure (Medical Outcomes Study 36-item Short Form Health Survey [SF-36]), mood state assessment (Profile of Mood States), neurocognitive tests, and serologic examination., Results: The prevalence of Lyme disease among adults on Nantucket Island was estimated to be 14.3% (95% CI, 9.3% to 19.1%). In multivariate analyses, persons with previous Lyme disease (mean time from infection to study evaluation, 6.0 years) had more joint pain (odds ratio for having joint pain in any joint, 2.1 [CI, 1.2 to 3.5]; P = 0.007), more symptoms of memory impairment (odds ratio for having any memory problem, 1.9 [CI, 1.1 to 3.5]; P = 0.003), and poorer functional status due to pain (odds ratio for 1 point on the SF-36 scale, 1.02 [CI, 1.01 to 1.03]; P < 0.001) than persons without previous Lyme disease. However, on physical examination, case-patients and controls did not differ in musculoskeletal abnormalities, neurologic abnormalities, or neurocognitive performance. Persons with previous Lyme disease who had persistent symptoms after receiving treatment (n = 67) were more likely than those who had completely recovered to have had fever, headache, photosensitivity, or neck stiffness during their acute illness (87% compared with 13%; odds ratio, 2.4 [CI, 1.0 to 5.5]; P = 0.045); however, the performance of the two groups on neurocognitive tests did not significantly differ., Conclusions: Because persons with previous Lyme disease exhibited no sequelae on physical examination and neurocognitive tests a mean of 6.0 years after infection, musculoskeletal and neurocognitive outcomes seem to be favorable. However, long-term impairment of functional status can occur.

Goal: To explore the influence of social, psychological, and health factors on self-report of function., Subjects: A convenience sample of 289 community-dwelling elderly aged 65-97 years., Methods: We compared a measure of function based on observed performance, the Physical Capacity Evaluation (PCE) with a self-reported measure of functional limitations (HAQ), in a cross-sectional study. Stepwise multiple regression identified variables predicting self-reported disability, controlling for observed function., Results: Controlling for PCE, self-reports of greater disability (HAQ) were predicted by current joint pain or stiffness, use of prescription medications, urban dwelling, depression, female gender, lack of memory problems, arthritis and lack of exercise. A final model included recent decline in function, dissatisfaction with function, gender, joint pain or stiffness, and observed function, explaining 85% of the variance in self-reported disability. The hypothesis that aging is associated with declining expectations of functional ability was not supported. However, recent health problems affected participants' reporting of limitations, consistent with a recalibration-type response shift. Perceived decline in function over the past six months, a fall within the last month, illness in the last week and pain or stiffness on the day of the exam all raised self-reports of disability. As suggested by adaptation level theory, subjects with recent problems might have an inflated perception of limitations due to shifts in their internal standards. When administered first, the observed performance test improved correlations between observed and self-reported function, primarily among those who did not report a recent decline in function. This suggests that this group may have benefited more from salient information about their abilities provided by performing the PCE before self-report., Conclusion: Our data confirm the importance of social, psychological, and health influences in self-report of disability, and are consistent with the hypothesis that people may recalibrate their self assessments based on recent health problems.

Objective: To study the outcome of Lyme disease (LD) in children identified in a total population survey of an endemic island., Methods: We conducted a population-based retrospective cohort study off the coast of Massachusetts. Twenty-five children who met the Centers for Disease Control case definition for prior LD were compared with 26 children without LD from the same community. All children with LD received antibiotics during the acute phase of their disease. All 51 children were invited for a clinical evaluation, including 12-lead electrocardiogram (EKG), and measurement of antibodies to Borrelia burgdorferi by antibody-capture ELISA and Western blot., Results: At a mean of 3.2 years from the initial manifestation of LD, children with prior LD did not have a higher prevalence of musculoskeletal or neurological symptoms, examination abnormalities, abnormal EKG, or behavioral difficulties, compared to children with no history of LD., Conclusion: Children who receive appropriate antimicrobial therapy for LD appear to have no demonstrable longterm morbidity.

Background: Cardiac involvement is common in acute Lyme disease, and case reports suggest that cardiac abnormalities might also occur years after the primary infection., Objective: To determine the prevalence of cardiac abnormalities in persons with previously treated Lyme disease., Design: Population-based, retrospective cohort study with controls., Setting: Nantucket Island, Massachusetts., Participants: From among 3703 adult respondents to a total-population (n = 6046) mail survey, 336 (176 case-patients and 160 controls) were randomly selected for clinical evaluation., Measurements: Current cardiac symptoms and major or minor abnormal electrocardiographic features, including heart rate; rhythm; axis; PR, QRS, and QT intervals; QRS structure; atrioventricular blocks; and ST-segment and T-wave changes., Results: Persons with Lyme disease (case-patients, n = 176) (mean duration from disease onset to study evaluation, 5.2 years) and persons without evidence of previous Lyme disease (controls, n = 160) did not differ significantly in their patterns of current cardiac symptoms and electrocardiographic findings, including heart rate (P > 0.2), PR interval (P = 0.15), QRS interval (P > 0.2), QT interval (P > 0.2), axis (P > 0.2), presence of arrhythmias (P > 0.2), first-degree heart block (P = 0.12), bundle-branch block (P > 0.2), and ST-segment abnormalities (P > 0.2). In multivariate analyses that adjusted for age, sex, and previous heart disease, a history of previously treated Lyme disease was not associated with either major (odds ratio, 0.78; P > 0.2) or minor (odds ratio, 1.09; P > 0.2) electrocardiographic abnormalities., Conclusion: Persons with a history of previously treated Lyme disease do not have a higher prevalence of cardiac abnormalities than persons without a history of Lyme disease.

Background: Tick bite control is an important initiative to prevent Lyme disease and other tickborne infections. While several studies have demonstrated that knowledge and awareness of Lyme disease in endemic areas are good, none has evaluated the relative importance of knowledge with other attitudinal and health belief variables to determine motivators of preventive behavior., Methods: We conducted a cross-sectional analysis of 304 commuter ferry passengers departing Martha's Vineyard Island, Massachusetts, in August 1992, to ascertain the prevalence of tick-avoidance behaviors among individuals from an endemic area of Lyme disease and to identify the knowledge, behavioral, and demographic variables that best determine precautionary behavior., Results: Overall, survey respondents (n = 304) had very good knowledge of Lyme disease (73% items correct on a knowledge test), but only 59% of respondents reported limiting time in tick areas, 58% usually wore protective clothing, 40% wore tick repellent, and 66% usually performed tick checks. By stepwise linear regression analysis, determinants of tick-avoidance behaviors included perceiving the behavior's benefits as outweighing its inconvenience (P < .0001), having confidence in recognizing Lyme disease symptoms (P < .0004), believing that Lyme disease is a serious illness (P < .0009), and believing that the avoidance behavior is effective in reducing the risk of Lyme disease (P < .01). Younger respondents (P < .05) performed fewer avoidance behaviors. Visitors (P < .0001) performed fewer tick checks than residents. Having confidence that one could find a tick on oneself with a tick check also predicted performance (P < .008). Increased general knowledge about Lyme disease did not predict any protective behaviors., Conclusions: Precautionary behaviors were underperformed in an at-risk population despite good knowledge of Lyme disease symptoms and transmission. Instead, performance was related to confidence in finding a tick on oneself and a perception that a precaution's benefit outweighed its inconvenience and would adequately reduce risk for Lyme disease. These data have implications for Lyme disease prevention programs, which typically focus on enhancing general knowledge as a means toward disease reduction.

The comparison between the size and shape (form) of two structures or the analysis of one object under differing conditions is important in restorative dentistry. Despite rapid advances in digitizing technologies, form comparison is still mainly limited to scalar measurements. The objective of this study was to test the potential use of a newly developed tensorial morphometric difference technique, the macroelement method, in a model restrative system where the processing and materials properties are known duplication of a denture anchor in stone via polysulfide, addition silicone, and polyether impression materials. Nine machined landmarks were utilized to construct a nine-sided element for macroelement analysis. Macroelement results compared well with the known impression materials properties of polymerization shrinkage and incomplete recovery in terms of: (1) larger die diameter, (2) smaller die (vertically), (3) horizontal direction of maximum expansion, and (4) vertical direction of maximum contraction. Also, macroelement results along boundary lines were equal to the traditional form difference measure of change in length/length of those lines. The macroelement method provided results which are superior to those of traditional methods in that both (1) the magnitude and direction of difference at any point on the structure could be determined, and (2) the graphical representation of the results provides an intuitive appreciation of how and where the forms differ Therefore, since macroelement results: (1) compare well with known materials properties and traditional measures, and (2) have the above-stated advantages, tensorial techniques such as the macroelement method, used in conjunction with new digitizing technologies, can be used better to describe the kinematics of form difference. With the description of the kinematics provided by the technique, the dynamic cause of the form difference can be ascertained with the investigators knowledge of materials. The investigators can then suggest changes to be made in materials and/or techniques that would enable the desired size and shape to be obtained.

The Société Internationale de Chirurgie Orthopédique et de Traumatologie (SICOT), the Task Force on Outcome Studies of The American Academy of Orthopaedic Surgeons, and The Hip Society reached a consensus on the nomenclature to be used for the evaluation of the results of total hip arthroplasty. The Task Force of The American Academy of Orthopaedic Surgeons, to assess the results of total hip arthroplasty from the perspective of the patient, subsequently developed a questionnaire that incorporated this nomenclature. The validity and reliability data regarding this questionnaire are reported in this study. Twenty-five patients participated in the reliability test. The non-response rate was five (0.5 per cent) of 941 possible responses. Test-retest reliability was determined by calculating the Spearman correlation coefficients for each question. The coefficients ranged from 0.41 to 1.0 over a mean test-retest interval of sixteen days. Most items had Spearman coefficients that were greater than 0.50, indicating good or excellent reliability. Validity was assessed, for the fifty-four patients who participated, by calculating the Spearman correlation coefficients for the items regarding pain in the affected hip, limitation of usual activities, capacity for walking without support, and the Sickness Impact Profile. The coefficients ranged from 0.11 (pain and limitation of activity) to 0.56 (Sickness Impact Profile and limitation of activity). These coefficients reflected modest associations, as anticipated, indicating that pain, function, and health status are related yet distinct concepts.(ABSTRACT TRUNCATED AT 250 WORDS)

Few studies have examined the consequences of the high prevalence of diabetes in Aboriginal communities. We aimed to determine the rates and causes of mortality in all Aboriginal central Australians with diagnosed diabetes, identified by a previous study (n =374). Cohort members were followed from 1 January 1984, or the date of diagnosis (to 31 December 1986), to 31 December 1991 or death. Death certificates, medical notes and autopsy reports were examined for cause of death. There were 130 deaths in 2280.7 person-years of follow-up. Standardised mortality ratios for Aboriginal people with diabetes, compared to the Northern Territory Aboriginal population, were 209 (95 per cent confidence interval (CI) 158 to 273) for men and 169 (CI 129 to 218) for women. The difference in ratios for men and women was not statistically significant when adjusted for age (P = 0.2). The eight-year survival rates for men and women diagnosed between 1984 and 1986 were 55.8 per cent (CI 32.6 to 73.7) for men and 80.3 per cent (CI 64.8 to 89.5) for women. Renal disease was the direct cause of death in 22.3 per cent. Infection accounted for 20.8 per cent of deaths and ischaemic heart disease for 13.8 per cent. Forty-four per cent of death certificates made no mention of diabetes. Diabetes confers an additional risk of death on a population whose mortality is already markedly worse than that of other Australians. Unlike Western diabetic populations, infections and renal disease were more common causes of death than macrovascular disease. Diabetes amplifies the effect of the community prevalence of infection and renal disease.

The Physical Capacity Evaluation, a performance measure of functional capabilities comprised of 13 tasks simulating those used in activities of daily living, was tested on 289 community-dwelling elderly people and compared against a widely used self-report measure of function, the Health Assessment Questionnaire. Factor analysis identified one dominant component in each instrument. Internal consistency reliability (Cronbach's alpha) was .90 for both instruments. Global disability (Health Assessment Questionnaire) and function (Physical Capacity Evaluation) scores were correlated -.74. One-week retest reliabilities on 58 subjects were .94 for the Physical Capacity Evaluation and .95 for the Health Assessment Questionnaire. The Physical Capacity Evaluation is a valid and reliable measure of physical performance for use with elderly people.

Objective: To ascertain the prevalence of and risk factors for long-term sequelae from acute Lyme disease., Design: Population-based, retrospective cohort study., Setting: A coastal region endemic for Lyme disease., Participants: Patients with a history of Lyme disease who were previously treated with antibiotics were compared with randomly selected controls., Measurements: A standardized physical examination, health status measure (Short Form 36), psychometric test battery, and serologic analysis., Results: Compared with the control group (n = 43), the Lyme group (n = 38; mean duration from disease onset to study evaluation, 6.2 years) had more arthralgias (61% compared with 16%; P < 0.0001); distal paresthesias (16% compared with 2%; P = 0.03); concentration difficulties (16% compared with 2%; P = 0.03); and fatigue (26% compared with 9%; P = 0.04), and they had poorer global health status scores (P = 0.04). The Lyme group also had more abnormal joints (P = 0.02) and more verbal memory deficits (P = 0.01) than did the control group. Overall, 13 patients (34%; 95% CI, 19% to 49%) had long-term sequelae from Lyme disease (arthritis or recurrent arthralgias [n = 6], neurocognitive impairment [n = 4], and neuropathy or myelopathy [n = 3]). Compared with controls, patients who had long-term sequelae had higher IgG antibody titers to the spirochete (P = 0.03) and received treatment later (34.5 months compared with 2.7 months; P < 0.0001)., Conclusions: Persons with a history of Lyme disease have more musculoskeletal impairment and a higher prevalence of verbal memory impairment when compared with those without a history of Lyme disease. Our findings suggest that disseminated Lyme disease may be associated with long-term morbidity.

Diabetes is a major public health problem for Aboriginal Australians. We wished to determine the extent and pattern of health service utilisation by Aboriginal people with diabetes in central Australia. Medical records of all Aboriginal people known to have diabetes (n = 374), identified by a previous study, were examined for attendance to health services in central Australia. All had non-insulin-dependent diabetes. Between January 1984 and December 1986, Aboriginal adults with diabetes were admitted to hospital on 694 occasions, accounting for 10.8% of adult Aboriginal admissions. The crude admission rates were 0.78 and 0.84 per diabetes-year for men and women, respectively. The age-adjusted relative risks for admission, compared with Aboriginal non-diabetic patients, were 2.93 (95% C.I., 2.62-3.26) for men and 2.46 (95% C.I., 2.28-2.66) for women. If admission for conditions associated with diabetes are excluded, the admission rates were similar for the two groups. Infection was the most common reason for attendance to a health service, representing 41.7% and 39.8% of male and female admissions, and 21.8% and 26.3% of male and female outpatient attendances. Aboriginal patients with diagnosed diabetes suffer high morbidity and contribute disproportionately to health system costs.

Short measures of health status are used increasingly in health services research, yet their sensitivities to clinical change have not been compared with longer, established instruments. In this study, 5 health status measures were administered preoperatively and 3 months postoperatively to 54 patients undergoing total hip arthroplasty. These instruments included the Sickness Impact Profile (SIP)--an established, long measure--and 4 short forms: the SF-36, Functional Status Questionnaire, shortened Arthritis Impact Measurement Scales, and Modified Health Assessment Questionnaire. Scores for physical, psychological, and global dimensions were constructed by aggregating subscales. Sensitivity to change, or responsiveness, was expressed with the standardized response mean (SRM), calculated as the mean change in score divided by the standard deviation of the change in score. The sampling distribution of the SRM was estimated with a jackknife procedure. Preoperative scores were moderately to highly correlated across instruments. The physical and global dimension SRMs of the brief health status measures ranged from 0.85 to 1.27 and were as large as or larger than the corresponding SIP SRMs. The SIP had the highest SRM on the psychological dimension. None of the instruments was significantly more sensitive than the others at the critical value (P = 0.005) adjusted for multiple comparisons. The brief health status measures were equally or more responsive than the SIP after total hip arthroplasty in the physical and global dimensions. Much larger samples are required to demonstrate statistically significant differences in SRMs among instruments.

Objective: To determine hospital-based morbidity and mortality from bacterial infections among Aboriginal people with diabetes in central Australia., Design: Examination of medical records on diabetic inpatients between January 1984 and December 1986., Setting: Alice Springs Hospital in central Australia, covering an Aboriginal population of about 12,500 people., Patients: Subjects admitted with a bacterial infection (n = 165) were selected from the database of all Aboriginal people known to have diabetes in the region (n = 374; all had non-insulin dependent diabetes)., Main Outcome Measures: Number of admissions, type and site of infections, causative organisms, duration of hospital stay and cause of death., Results: The 281 admissions for infections accounted for 4.6% of adult Aboriginal admissions to hospital. Thirteen patients died. Eleven patients required amputation of a digit or limb. In 1986, 13/200 patients admitted with diabetes had bacteraemia compared with 14/1885 patients who did not have diabetes. One patient had Fournier's gangrene, one had malignant otitis externa, one community acquired Acinetobacter pneumonia, one pneumonia with Succinivibrio spp. found in blood cultures, and one meningitis and transverse myelopathy with Streptococcus milleri found in blood cultures., Conclusions: The frequency, type and severity of infections in the relatively young patients result in high personal costs to the community and financial costs to the health care system. Standard preventive measures must be implemented to control severe bacterial infections among subjects with diabetes in this socially and economically marginalised population group.

The prevalence of diagnosed diabetes in Aboriginal people living in central Australia (population, 9983) was determined by collating data from the hospital, rural and urban health services, nursing homes and death registers. A total of 98 male and 183 female Aboriginal residents with diabetes attended health services in central Australia between January 1984 and December 1986. The point prevalence of diagnosed diabetes at the end of 1986 in the age group 25-34 years was 1.6% in men and 3.1% in women, and in those over 35 years, 8.8% and 14.1%, respectively. The true prevalence of diabetes (diagnosed and undetected) is likely to be at least twice this rate, and constitutes a major public health problem in central Australia. Diabetes and other disorders such as obesity, hypertension and ischaemic heart disease have common antecedents and outcomes. The control of these non-communicable diseases requires integrated and culturally appropriate educational, social and medical strategies.

The intravaginal application of prostaglandin E2 for preinduction cervical ripening has proved to be advantageous in the management of patients with an unfavorable cervix. The purpose of this double-blind randomized investigation was to compare the efficacy and safety of two methods of prostaglandin E2 delivery. Patients who were to have preinduction cervical ripening because of an unfavorable cervix (Bishop score less than or equal to 4) were randomly assigned to be given a single dose of prostaglandin E2 as either 2.5 mg of gel or a 3.0 mg "chip" intravaginally in a placebo-controlled manner. Sixty-nine patients received the active prostaglandin E2, 34 in the gel group and 35 in the "chip" group. The groups were similar in maternal age, race, parity, gestational age, and initial Bishop score. Both forms of prostaglandin E2 were easy to administer and helpful in priming an unfavorable cervix. The need for, duration of, and maximum dose of oxytocin were similar in both groups. Cesarean delivery because of failed induction occurred in 5 of 35 (14.3%) patients receiving a "chip" and 4 of 34 (11.8%) receiving the gel. However, patients receiving a "chip" experienced a 20% (7/35) incidence of hyperstimulation, compared with 2.9% (1/36) in those receiving the gel (p less than 0.05). The only case requiring immediate cesarean delivery because of intractable uterine hyperstimulation received a "chip." We conclude that both methods were effective for cervical ripening, but the lower incidence of uterine hyperstimulation seen with the gel would suggest that it is preferable to the "chip."

The interrelations between cold sensitivity and release of histamine and other mediators in five patients with cold urticaria undergoing cold tolerance treatment were studied. Tolerance to cold was produced in all patients by repeated cold exposure. In four patients tolerance was maintained by once daily exposures. In the fifth patient 4-hourly exposures were necessary. Cold sensitivity was associated with histamine release in venous blood draining urticated skin. No prostaglandin activity was detected, and low concentrations of kinin activity were found in blood draining the normal and exposed skin of healthy subjects as well as in patients with cold urticaria. After induction of tolerance, no histamine release occurred on challenge by cold. Relapse of sensitivity was associated with reappearance of histamine release on challenge. The conclusion that tolerance is due to depletion of histamine stores in skin after repeated cold exposure was supported by diminished wealing in response to injection of a histamine liberator (compound 48/80) in cold-tolerant skin.

A 50-year-old man with recurrent life-threatening sepsis and a cutaneous condition resembling pyoderma gangrenosum, was found to have a defect of neutrophil phagocytic function. Phagocytosis could be enhanced by corticosteroids, both in vitro in a dose-dependent manner, and in vivo, when it was accompanied by rapid clinical improvement. Studies with steroid hormones and immuno-stimulatory drugs are described.

Four African female patients are described, who presented with the features of systemic sclerosis. Overlapping features of lupus erythematosus or dermatomyositis were present in three cases but were not prominent. Direct immunofluorescence of uninvolved skin revealed a particulate (or speckled) epidermal nuclear staining, with specificity for IgG. In view of the reported association between this finding and mixed connective tissue disease, these patients were treated with corticosteroids and marked improvment occurred in all cases. The usefulness of this investigation in making the distinction between systemic sclerosis and mixed connective tissue disease and in indicating a potentially effective form of therapy is discussed.

Thirteen patients with cold urticaria were studied to assess the effect of the systemic drug doxantrazole, which has actions resembling disodium cromoglycate, on cold evoked histamine release. The patients, all of whom developed an immediate local whealing response after cooling of the forearm, demonstrated release of histamine into venous blood draining that forearm. Following doxantrazole treatment, significant suppression of histamine release occurred. In some but not all patients this was accompanied by diminution of urtication in response to cooling. A double-blind study was carried out in 3 subjects, all of whom showed diminished cold-stimulated histamine release after doxantrazole. Two of these showed clinical improvement. Doxantrazole had no effect on erythema due to intradermal histamine, but did suppress the erythematous reaction to intradermal injection of compound 48/80. Our results suggest that doxantrazole or related anti-allergic agents might be useful in the treatment of cold urticaria.

The effects of prostaglandins E1 and F2alpha (PGE1 and PGF2alpha) on the growth of guinea pig epidermis have been studied in vivo. The prostaglandins were injected intradermally into guinea pigs, and tritiated thymidine was injected intraperitoneally prior to sacrifice. The autoradiographic labelling indices (L.I.) were assessed and a significant increase was found 4 h after injection of PGE1 -an effect which lasted for up to 72 h. PGF2alpha injections had no significant effect on the L.I.

Two hundred moles were examined histologically and the degree and type of epidermal change was recorded and correlated with the arrangement, density and type of naevus cells present and with the clinical presentation. Resemblances to the epidermal architecture of seborrhoeic warts were noted in 49% of the moles studied (this type of change was mainly seen in younger patients). In these there was a predominance of epithelioid cells, mainly in the junctional and upper dermal zones. Thirty-five per cent of moles possessed an epidermis with an overall appearance of being stretched, beneath which was a relatively clear zone followed by a uniform distribution of predominantly "lymphocytoid" naevus cells and large numbers of naevus cells of the giant type. These were found mainly in the older age groups. A third group (11%) was characterized by the presence of bulbous epidermal rete ridges and many junctional nests of naevus cells. This group was found mainly in younger age groups and there was often a history of recent change in the mole. It is concluded that the epidermal component of moles might itself be a naevoid disorder or result from the dermal disturbance induced by the mole cells.