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91.
AIMS: To examine whether cocaine abusers differ from non-abusers in their frequency and enjoyability of engaging in various "pleasant events", in order to approximate the density of positive reinforcement experienced in their natural environment. DESIGN: Comparisons of cocaine abusers to normative data and matched controls. SETTING: An outpatient substance abuse treatment center in Burlington, Vermont, USA. PARTICIPANTS: Subjects included 100 individuals enrolled in outpatient treatment for cocaine abuse or dependence and 50 community volunteers without histories of drug abuse or other major psychiatric illness and matched to cocaine-dependent patients on age, sex and SES. MEASUREMENTS: Diagnostic assessments were based upon clinical interviews using the DSM-III-R checklist. The primary focus of this study was the Pleasant Events Schedule (PES), a self-rated behavioral inventory of the frequency and enjoyability of engaging in "pleasant" activities. Cocaine use history, treatment outcome and other relevant variables were also assessed. FINDINGS: Cocaine abusers reliably reported lower frequency of non-social, introverted, passive outdoor and mood-related activities than controls. These differences remained after controlling for demographic and life-style differences between groups, with the exception of mood-related activities. Perceived enjoyability of the activities did not differ across groups. Intravenous cocaine use and prior treatment for cocaine abuse predicted particularly low frequency of pleasant activities. Greater frequency of non-social activities predicted better treatment outcome. CONCLUSIONS: Drug abuse is associated with low density of certain types of non-drug reinforcement. Systematic increases in these activities may improve treatment outcome. 相似文献
92.
Operative management of Haglund's deformity in the nonathlete: a retrospective study 总被引:1,自引:0,他引:1
Haglund's deformity, or "pump bump," is a common cause of posterior heel pain. Management of the condition usually consists of nonoperative therapy. This study presents a retrospective study of 65 cases (53 patients), with symptomatic Haglund's deformity in nonathletes (13 male and 40 female), who presented during a 4-year period (1989-1994). Sixty-five percent (39 heels) of these patients failed to respond to nonoperative therapy for an average of 62 weeks, (range, 4-260 weeks). This group of patients went on to operative treatment. Surgical management consisted of excision of the posterior calcaneal tuberosity through a medial longitudinal incision with debridement, reattachment of the Achilles tendon using bone anchors, and 4 weeks of postoperative immobilization. Thirty-nine patients (74%) were contacted for follow-up. The average follow-up period for these patients was 155 weeks, (range, 92-335 weeks). There were 50% excellent results, 47% good results, 3% fair results (1 patient), and no poor results. The Maryland Foot Score for operated heels was an average of 67/100 preoperative and an average of 92/100 postoperative. On unoperated heels the score was an average of 81/100 at first evaluation and an average of 86/100 at final evaluation. Complications included one recurrence of painful prominence, one wound infection, and one incisional neuroma. The outcome of these cases demonstrated that in those patients who fail nonoperative treatment, surgical treatment of Haglund's deformity produces a predictably good surgical result when performed using the technique described. 相似文献
93.
94.
GJ Argyros JM Roach KM Hurwitz AH Eliasson YY Phillips 《Canadian Metallurgical Quarterly》1996,109(6):1520-1524
A variety of dosing schedules have been reported for the hyperventilation method of broncho-provocation testing. To evaluate the effect of challenge technique on the bronchoconstrictive response, we had 16 subjects perform eucapnic voluntary hyperventilation (EVH) with dry, room temperature gas using four different dosing schedules. The hyperventilation challenge dosages included the following: (1) a target minute ventilation (VE) of 20 x FEV1 for 6 min; (2) a target VE of 15 x FEV1 for 12 min; (3) an interrupted challenge with a target VE of 30 x FEV1 for 2 min repeated 3 times; and (4) a target VE of 30 x FEV1 for 6 min. Challenges 2, 3, and 4 gave identical absolute ventilatory challenges (identical factor FEV1 x minutes) but at different VE dosages or time. Challenges 1 and 4 were of identical length, but different target VE. The mean postchallenge fall in FEV1 was 16.6 +/- 10.9%, 11.0 +/- 8.1%, 19.6 +/- 9.9%, and 26.7 +/- 11.3% for challenges 1, 2, 3, and 4, respectively. The response to an identical EVH challenge (FEV1 x 30 for 6 min) was reproducible when performed on separate days. We conclude that the challenge technique used for hyperventilation testing will have a significant impact on the bronchoconstrictive response and must be taken into account when interpreting study results. Tests may be quantitatively comparable over a narrow range of challenge time and VE. We recommend that a 6-min uninterrupted EVH challenge using dry, room temperature gas at a target VE of 30 x FEV1 be adopted as the "standard" challenge. 相似文献
95.
96.
Caio César Mori Carélo Ives Renê Venturini Pola Ricardo Rodrigues Ciferri Agma Juci Machado Traina Caetano Traina Jr Cristina Dutra de Aguiar Ciferri 《Information Systems》2011
Searching in a dataset for elements that are similar to a given query element is a core problem in applications that manage complex data, and has been aided by metric access methods (MAMs). A growing number of applications require indices that must be built faster and repeatedly, also providing faster response for similarity queries. The increase in the main memory capacity and its lowering costs also motivate using memory-based MAMs. In this paper, we propose the Onion-tree, a new and robust dynamic memory-based MAM that slices the metric space into disjoint subspaces to provide quick indexing of complex data. It introduces three major characteristics: (i) a partitioning method that controls the number of disjoint subspaces generated at each node; (ii) a replacement technique that can change the leaf node pivots in insertion operations; and (iii) range and k-NN extended query algorithms to support the new partitioning method, including a new visit order of the subspaces in k-NN queries. Performance tests with both real-world and synthetic datasets showed that the Onion-tree is very compact. Comparisons of the Onion-tree with the MM-tree and a memory-based version of the Slim-tree showed that the Onion-tree was always faster to build the index. The experiments also showed that the Onion-tree significantly improved range and k-NN query processing performance and was the most efficient MAM, followed by the MM-tree, which in turn outperformed the Slim-tree in almost all the tests. 相似文献
97.
Paulo Anselmo da Mota Silveira Neto Ivan do Carmo Machado John D. McGregorEduardo Santana de Almeida Silvio Romero de Lemos Meira 《Information and Software Technology》2011,53(5):407-423
Context
In software development, Testing is an important mechanism both to identify defects and assure that completed products work as specified. This is a common practice in single-system development, and continues to hold in Software Product Lines (SPL). Even though extensive research has been done in the SPL Testing field, it is necessary to assess the current state of research and practice, in order to provide practitioners with evidence that enable fostering its further development.Objective
This paper focuses on Testing in SPL and has the following goals: investigate state-of-the-art testing practices, synthesize available evidence, and identify gaps between required techniques and existing approaches, available in the literature.Method
A systematic mapping study was conducted with a set of nine research questions, in which 120 studies, dated from 1993 to 2009, were evaluated.Results
Although several aspects regarding testing have been covered by single-system development approaches, many cannot be directly applied in the SPL context due to specific issues. In addition, particular aspects regarding SPL are not covered by the existing SPL approaches, and when the aspects are covered, the literature just gives brief overviews. This scenario indicates that additional investigation, empirical and practical, should be performed.Conclusion
The results can help to understand the needs in SPL Testing, by identifying points that still require additional investigation, since important aspects regarding particular points of software product lines have not been addressed yet. 相似文献98.
Ricardo Enrique Gutiérrez-Carvajal João Maurício Rosário J.A. Tenreiro Machado 《International journal of systems science》2016,47(9):2169-2177
While fractional calculus (FC) is as old as integer calculus, its application has been mainly restricted to mathematics. However, many real systems are better described using FC equations than with integer models. FC is a suitable tool for describing systems characterised by their fractal nature, long-term memory and chaotic behaviour. It is a promising methodology for failure analysis and modelling, since the behaviour of a failing system depends on factors that increase the model’s complexity. This paper explores the proficiency of FC in modelling complex behaviour by tuning only a few parameters. This work proposes a novel two-step strategy for diagnosis, first modelling common failure conditions and, second, by comparing these models with real machine signals and using the difference to feed a computational classifier. Our proposal is validated using an electrical motor coupled with a mechanical gear reducer. 相似文献
99.
Analysis of factors contributing to success in a program of micromanipulation-assisted fertilization
GJ Garrisi AJ Chin PM Dolan HM Nagler M Vasquez-Levin D Navot JW Gordon 《Canadian Metallurgical Quarterly》1993,59(2):366-374
OBJECTIVE: To determine factors important to clinical success in micromanipulation-assisted in vitro fertilization (IVF). DESIGN: Procedures invoked in two separate series of micromanipulation-assisted IVF cycles, one unsuccessful (series I) and the other successful (series II), were compared in an effort to identify changes that led to clinical success. SETTING: University-based IVF clinic. PATIENTS: In both IVF series involving micromanipulation, patients consisted of infertile couples who fit any of five categories of male-factor related infertility. The female patients underwent controlled hyperstimulation for oocyte retrieval and the oocytes were inseminated normally or were subjected either to partial zona dissection or subzonal sperm insertion to assist fertilization. Results in all groups were compared between the two patient series. RESULTS: In the successful series II, a noticeable improvement in fertilization rate and embryo quality was observed compared with series I. A significant increase in the percentage of patients reaching embryo transfer, the pregnancy rate per transfer, and the pregnancy rate per retrieval were noted in series II; a 25% ongoing pregnancy rate per retrieval was observed overall in this successful group, with "ongoing" defined as manifestation of at least a fetal sac on ultrasound with no detectable problems. Patients with a mixed transfer of embryos derived from manipulated and normally inseminated oocytes had a 75% rate of pregnancy per transfer in series II. Differences between the two series could not be attributed to patient selection or biases in selection of oocytes relegated to micromanipulation. However, oocyte handling, micromanipulation, and culture protocols differed significantly between the two series in that temperature and pH of oocytes was better controlled, and micromanipulation time was minimized in series II. CONCLUSION: Success in micromanipulation depends on maintenance of the oocyte in a stable and supportive environment throughout the micromanipulation procedure. It is also important to minimize trauma to the eggs by performing micromanipulation rapidly and with minimal distortion of the egg. Patients with a poor fertilization rate in standard IVF may experience a substantial increase in the likelihood of pregnancy when micromanipulation-assisted fertilization is performed on some eggs. 相似文献
100.
GJ Makari 《Canadian Metallurgical Quarterly》1993,29(1):8-21
In the 1830s the time-honored notion that excess study could lead to madness underwent a significant change in America. Under the influence of Enlightenment pedagogy and phrenology, influential superintendents like Amariah Brigham and Isaac Ray feared that the "unnatural" overstimulation of children in schools would ruin their development. In the second half of the nineteenth century, as belief in environmental determinism waned and assumptions about what is "natural" changed, this psychiatric etiology was debated; then, overthrown. By the turn of the century, education was thought to aid, not harm, the mentally ill. 相似文献